Foreign Body-type Reaction Research Articles

Use of F18 bioglass putty for induced membrane technique in segmental bone defect of the radius in rabbits.

To evaluate the inductive capacity of F18 bioglass putty on the induced membrane technique in a segmental bone defect of the rabbit's radius. Ten female Norfolk at 24 months of age were used. The animals were randomly separated based on postoperative time points: five rabbits at 21 and four at 42 days. A 1-cm segmental bone defect was created in both radii. The bone defects were filled with an F18 bioglass putty. Immediate postoperative radiographic examination revealed the biomaterial occupying the segmental bone defect as a well-defined radiopaque structure with a density close to bone tissue. At 21 and 42 days after surgery, a reduction in radiopacity and volume of the biomaterial was observed, with particle dispersion in the bone defect region. Histologically, the induced membrane was verified in all animals, predominantly composed of fibrocollagenous tissue. In addition, chondroid and osteoid matrices undergoing regeneration, a densely vascularized tissue, and a foreign body type reaction composed of macrophages and multinucleated giant cells were seen. the F18 bioglass putty caused a foreign body-type inflammatory response with the development of an induced membrane without expansion capacity to perform the second stage of the Masquelet technique.

DP20 Necrobiotic santhogranuloma of the scalp with nonprogressive thrombocytopenia: a case report

Abstract We present the case of an 84-year-old woman referred with a 6-month history of a lesion on her occipital scalp. Examination revealed a creamy-white, nonscaly nodule measuring 15 × 15 mm with surface telangiectasia. Her past medical history included basal cell carcinoma, stage 3 kidney disease, cardiovascular disease and osteoporosis. A diagnosis of necrobiotic xanthogranuloma (NXG) was confirmed on incisional biopsy, and the patient went on to have full excision. Given the association with haematological malignancies, and following discussion with our local haematologist, investigations included full blood count, bone profile, immunoglobulins, serum and urinary protein electrophoresis and serum free light chains. This revealed a low platelet count of 108 × 109 cells L–1 (reference interval 150–450) but no other significant abnormalities. Our local haematologist considered a bone marrow biopsy, but after discussion with the patient, this was declined. Necrobiotic xanthogranuloma is a rare non-Langerhans histiocytosis. It classically presents as a yellow, red or purplish papule or nodule in the periorbital region, so this case had an unusual site. The mean age of onset is in the sixth decade of life, with an equal sex distribution. Pathogenesis is unknown. Necrobiotic xanthogranuloma is associated with haematological malignancies, particularly paraproteinaemia and lymphoproliferative disease. Differential diagnoses include xanthelasma, chronic lupus erythematosus, sarcoidosis and necrobiosis lipoidica. Where lesions become infiltrative and plaque-like, mycosis fungoides and psoriasis can also be considered. Given the relatively rare nature of NXG, there is no consensus for optimal treatment. In localized skin lesions such as in our patient, surgical excision is often undertaken. Other reported treatments are directed at the associated paraproteinaemia and include chlorambucil and small-dose corticosteroids, cyclophosphamide, melphalan, azathioprine, thalidomide, interferon-α and intravenous immunoglobulin. Classical features on histology include palisading xanthogranulomas with foci of necrobiosis in the mid-dermis and diffuse granulomatous panniculitis with foreign body-type reaction and Touton giant cells. Our histology slides showed a relatively atrophic epidermis with a dense dermal and subcutaneous infiltrate consisting of lymphocytes, foamy macrophages, plasma cells and Touton-type multinucleate giant cells with areas of necrobiosis. There were also reactive lymphoid follicles with germinal centres. Given the association with internal malignancy, it is important to diagnose these lesions correctly. To date, our patient has not developed any haematological malignancy, although is at increased risk in the future and has been counselled and monitored accordingly. It remains unclear whether the presence of thrombocytopenia alongside NXG is a coincidental finding or marker for future lymphoproliferative disease, as there are no other published case reports of such an association.

Tissue response, macrophage phenotype, and intrinsic calcification induced by cardiovascular biomaterials: Can clinical regenerative potential be predicted in a rat subcutaneous implant model?

The host immune response to an implanted biomaterial, particularly the phenotype of infiltrating macrophages, is a key determinant of biocompatibility and downstream remodeling outcome. The present study used a subcutaneous rat model to compare the tissue response, including macrophage phenotype, remodeling potential, and calcification propensity of a biologic scaffold composed of glutaraldehyde-fixed bovine pericardium (GF-BP), the standard of care for heart valve replacement, with those of an electrospun polycarbonate-based supramolecular polymer scaffold (ePC-UPy), urinary bladder extracellular matrix (UBM-ECM), and a polypropylene mesh (PP). The ePC-UPy and UBM-ECM materials induced infiltration of mononuclear cells throughout the thickness of the scaffold within 2 days and neovascularization at 14 days. GF-BP and PP elicited a balance of pro-inflammatory (M1-like) and anti-inflammatory (M2-like) macrophages, while UBM-ECM and ePC-UPy supported a dominant M2-like macrophage phenotype at all timepoints. Relative to GF-BP, ePC-UPy was markedly less susceptible to calcification for the 180 day duration of the study. UBM-ECM induced an archetypical constructive remodeling response dominated by M2-like macrophages and the PP caused a typical foreign body reaction dominated by M1-like macrophages. The results of this study highlight the divergent macrophage and host remodeling response to biomaterials with distinct physical and chemical properties and suggest that the rat subcutaneous implantation model can be used to predict in vivo biocompatibility and regenerative potential for clinical application of cardiovascular biomaterials.

Root cause determination of intraperitoneal catheter obstructions: Insulin amyloid aggregates vs foreign body reaction

Continuous intraperitoneal insulin infusion, from an implanted insulin pump connected to a catheter that delivers insulin directly to the peritoneal cavity has many clinical advantages for patients with Type 1 diabetes. However, the ongoing incidence of catheter obstructions remains a barrier to the widespread use of this therapy. To date, the root cause of these obstructions remains unknown. Here, a two-year clinical investigation was conducted, along with the development of an animal model to enable a mechanistic investigation into this issue. This novel animal model was able to mimic the catheter obstructions that occur in patients and, fortuitously, at an accelerated rate. This model allowed for independent assessment of each potential cause associated with catheter obstructions to help identify the root cause. Both macroscopic and microscopic analysis were conducted with regards to the onset and progression of catheter obstructions, along with monitoring of insulin delivery. Interestingly, although insulin aggregation occurs in insulin pumps and insulin aggregates were found in some catheter obstructions, insulin is unlikely to be the root cause, since obstructions also occurred in the control groups where only diluent (no insulin) was administered to the animals. Inflammatory cells, different phenotypes of fibroblasts, as well as collagen were observed in all obstructed catheters explanted from the patients and the animals. The presence of these cells and collagen is indicative of a typical foreign body reaction. In addition, the dynamic change in the fibroblasts with respect to morphology, phenotype, and spatial distribution suggests that tissue irritation-mediated epithelial to mesenchymal transition plays a role in catheter obstructions.

Collision Tumor in the Lower Eyelid: Basal Cell Carcinoma Adjacent to Trichoepithelioma.

The coexistence of 2 neoplasms in a single cutaneous specimen is unusual. We describe a lower eyelid lesion in which the biopsy revealed a trichoepithelioma (TE) and an adjacent basal cell carcinoma (BCC). A 57-year-old female patient reported a 5-year history of lower eyelid pruritus and had been treated for blepharitis elsewhere. She was referred for eyelid evaluation due to the presence of a plaque, loss of eyelashes, and areas of inflammation in the right lower eyelid. She underwent tumor excision, and the eyelid was reconstructed using an orbicularis muscle advancement flap combined with a free tarsoconjunctival graft and a skin graft. Preoperative photographs show an extensive lesion, with madarosis in the right lower eyelid (Fig. A and B). Biopsy specimen from the right lower eyelid revealed 2 different tumor types: a TE and an adjacent BCC (Fig. C and D). A focus of TE is seen (left) juxtaposed with a focus of BCC (right). The area containing the TE was composed of basaloid cell nests and horn cysts, embedded within an organized stroma. Areas of cicatricial fibrosis and foreign body-type reaction were also observed. These histopathology features were consistent with that of a desmoplastic TE (DTE). The adjacent BCC area showed proliferation of atypical basaloid cells with peripheral palisading. Cytoplasm was basophilic and relatively scant, nuclei were large and mildly irregular, and contained grumous chromatin and mitotic figures. Trichoepithelioma is a benign tumor of follicular origin with 3 distinctive variants: multiple familial, solitary, and DTE. DTE is a rare benign adnexal tumor, derived from basal cells in the outer root sheath of the hair follicle, histologically characterized by narrow strands of basaloid tumor cells, keratinous cysts, and a desmoplastic stroma. TEs and BCCs both present with nests of basaloid cells. Histologic features that favor TE include the following: architectural symmetry, horn cysts, and associated giant cell reaction (rare in BCC), papillary mesenchymal bodies, no high-grade atypia, no or very low mitotic activity, monomorphic nuclei, no tumor necrosis, no peripheral clefting. The presence of peripheral palisading of basaloid cells, clefting between the epithelial and stromal components, necrosis, and high mitotic activity are associated with BCC. When histologic examination does not permit to differentiate a TE from a BCC, immunohistochemical stains, such as BCL2, CD10, CD34, AR, may be useful. Transformation of TE to BCC is rare and usually occurs in the setting of multiple TEs. A possible way to investigate transformation would be to compare the DNA of both tumors to find a common mutation. In our patient, it is more likely that this is a collision tumor (coexistence of 2 different tumors in the same lesion). Concomitant presence of a TE and a BCC is rare, and, to the best of our knowledge, this is the only case showing a DTE adjacent to a BCC, involving the eyelid. This case highlights that benign and malignant pathology can coexist within the same lesion. Special attention should be addressed to collision tumors since, in these cases, a small incisional biopsy might not be sufficient for accurate diagnosis.Fig.: Basal cell carcinoma adjacent to trichoepithelioma. A and B, A 57-year-old female patient presented an extensive lesion, with madarosis in the right lower eyelid. C and D, Hematoxylin and eosin stain of the biopsy specimen (100× and 200×) revealed 2 different tumor types: a focus of trichoepithelioma is seen (left) juxtaposed with a focus of basal cell carcinoma (right).

Foreign Body Reaction to a Glass Splinter – A Case Report

We present a case of foreign body reaction to a glass splinter. This case depicts in the attached figures the typical foreign body reaction surrounding a non-organic foreign body. Meticulous dissection of the foreign body and the reactive tissue surrounding it are key to a swift and uneventful recovery.

Histological analysis of ACL reconstruction failures due to synthetic-ACL (LARS) ruptures.

Introduction:Anterior Cruciate Ligament (ACL) reconstruction is an established surgical procedure. Synthetic ligaments represent an option for ACL reconstruction. Their popularity declined for the raising concerns due to re-ruptures, knee synovitis and early arthritis related to I and II generation artificial ligaments. The introduction of a III generation synthetic ligament (Ligament Advanced Reinforcement System-LARS) permitted renewed interest in the adoption of this kind of graft. Main purpose of our study was to describe the histological findings on samples obtained from a consecutive series of ACL revision surgeries due to LARS ACL reconstruction failures. Secondary aim was to determine the reason for LARS rupture.Methods:In a period between 2016 and 2018 eleven patients underwent ACL revision surgery due to LARS ACL reconstruction failure. At the time of the arthroscopic procedure, samples of synovial membrane and remnants of the torn LARS were sent to the Pathological-Anatomy Institute of our Hospital for a histological analysis.Results:Histological analysis of the synovial tissues confirmed the arthroscopic evidence of synovitis mainly characterized by chronic inflammation with predominance of multinucleated giant cells. The adoption of polarized light microscopy revealed the presence of brightly bi-refractive material (LARS wear particles) in the synovial tissue; at higher magnification wear debris were detected inside the cytoplasma of multi nucleated cells. The histological analysis of the removed LARS revealed a surrounding typical foreign body reaction with poor signs of fibrovascular ingrowth of the synthetic ligament.Conclusions:Our findings could not clearly advocate a unique mechanism of LARS-ACL reconstruction failure: biologic issues (poor tissue ingrowth) and mechanical issues (fibers properties and tunnel position) probably concur in a multi factorial manner. ACL reconstruction using artificial ligaments can not be considered a simple surgery. Artificial augments require some expertise and could therefore achieve better results if used by skilled sport surgeons other than trainees or low volume surgeons. The Authors believe that ACL reconstruction with synthetic devices still have restricted indications for selected patients (e.g. elderly patients who require a fast recovery, professional athlete, autologous tendons not available and/or refusing donor tendons). Our study arises additional suspicion on the unresponsiveness of synthetic fibers and claim some concern in the implantation of synthetic devices. (www.actabiomedica.it)

FOREIGN-BODY REACTION IN THE UPPER LIP: CASE REPORT

Foreign-body reaction is an inflammatory process caused by the presence of immunologically inert exogenous materials in the organism. A 47-year-old female patient, who was hairdresser, presented with an exophytic lesion in the upper lip, whose coloration was similar to that of the mucosa, which evolved over the course of 20 years. The patient reported no history of systemic diseases, submission to aesthetic procedures, or history of facial trauma. Thus, the clinical diagnosis was fibrous hyperplasia. After excisional biopsy, the histopathologic analysis revealed the presence of vacuoles and cells with clear cytoplasm compatible with macrophages in connective tissue. The immunohistochemical reaction for CD68 demonstrated strong diffuse immunoexpression in a large number of cells, confirming the presence of macrophages. The final diagnosis was foreign body type reaction. The patient is still under follow-up, and after 6 months there were no signs of recurrence. Foreign-body reaction is an inflammatory process caused by the presence of immunologically inert exogenous materials in the organism. A 47-year-old female patient, who was hairdresser, presented with an exophytic lesion in the upper lip, whose coloration was similar to that of the mucosa, which evolved over the course of 20 years. The patient reported no history of systemic diseases, submission to aesthetic procedures, or history of facial trauma. Thus, the clinical diagnosis was fibrous hyperplasia. After excisional biopsy, the histopathologic analysis revealed the presence of vacuoles and cells with clear cytoplasm compatible with macrophages in connective tissue. The immunohistochemical reaction for CD68 demonstrated strong diffuse immunoexpression in a large number of cells, confirming the presence of macrophages. The final diagnosis was foreign body type reaction. The patient is still under follow-up, and after 6 months there were no signs of recurrence.

Targeting Cx26 Expression by Sustained Release of Cx26 Antisense from Scaffolds Reduces Inflammation and Improves Wound Healing

AbstractThe gap junction protein connexin 26 (Cx26) is expressed at high levels in naturally hyperthickened epidermal layers as well as pathological hyperkeratotic disease states, such as warts, psoriatic plaques, and chronic wound edges. The overexpression of Cx26 is also linked with inflammation, breakdown of the skin barrier function, and perturbed wound healing. Here, a collagen scaffold implanted into a rat excisional skin wound is used. This induces a foreign body type reaction characterized by epidermal thickening with elevated levels of Cx43 and Cx26, increased inflammation, and perturbed healing. This is reminiscent of a chronic skin wound. If the same scaffolds are coated with an antisense molecule specifically targeting Cx26 that has a slow sustained release, this prevents the abnormal upregulation of Cx26 protein at the wound edge. Knocking down Cx26 protein levels below those seen in normal wound healing has no adverse effects on the healing process but instead reduces the epidermal thickening and also the inflammatory response, while at the same time promotes the healing response. Treatment with Cx43/26 antisense may promote healing of chronic wounds. The Cx26 antisense may also be helpful in treating other skin conditions where Cx26 is overexpressed.

Silicone-Induced Granuloma of Breast Implant Capsule (SIGBIC): Histopathology and Radiological Correlation.

Currently, attention has been given to complications related to breast implants, especially due to the presence of anaplastic large cell lymphoma (ALCL) related to silicone implants. Many manuscripts attempt to associate silicone presence with clinical complaints reported by patients, while others try to demonstrate the mechanisms of silicone bleeding by permeability loss of breast implant surfaces. There also are reports of foreign body type reactions from implant fibrous capsule to silicone corpuscles. However, there seems to be no study that correlates the clinical, radiological, and histological correlations of these lesions. The objective of this review is to correlate radiological findings of silicone-induced granuloma of breast implant capsule (SIGBIC) from breast MRI (BMRI) scans and complementary findings of ultrasound (US) and positron emission tomography (PET) scan, and its histology originated from surgical breast implant capsulectomy. To make this correlation possible, we divided SIGBIC into three radiological findings: (1) intracapsular SIGBIC, (2) SIGBIC with extracapsular extension, and (3) mixed SIGBIC associated with seroma. Our experience demonstrates histological-radiological correlation in SIGBIC diagnosis. Knowledge of these findings may demonstrate its real importance in terms of public health and patient management. We believe that SIGBIC is currently underdiagnosed by lack of training, guidance, and management in our clinical practice.

Antibacterial and Biocompatible Cross-Linked Waterborne Polyurethanes Containing Gemini Quaternary Ammonium Salts.

A cross-linked waterborne polyurethane (CPTMGPU) with long-term stability was developed from poly(ethylene glycol) (PEG), polyoxytetramethylene glycol (PTMG), isophorone diisocyanate (IPDI), l-lysine, and its derivative diamine consisting of gemini quaternary ammonium salt (GQAS), using ethylene glycol diglycidyl ether (EGDE) as a cross-linker. Weight loss test, X-ray photoelectron spectroscopy (XPS) measurements, and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) were performed to prove the surface structure and stability of these CPTMGPU films. Furthermore, the GQAS-bearing CPTMGPUs show repeatable contact-active antibacterial efficacy against both Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli) bacteria and do not show any inhibition effect against fibroblasts in vitro. After subcutaneous implantation in rats, the CPTMGPU films manifest good biocompatibility in vivo, despite the presence of a typical foreign body reaction toward surrounding tissues and mild systematic inflammation reaction that could be eliminated after a short implantation period, as demonstrated by histology and immunohistochemistry combined with interleukin (IL)-1β, IL-4, IL-6, IL-10, and TNF-α analysis though enzyme-linked immunosorbent assay (ELISA) and real-time quantitative polymerase chain reaction (qRT-PCR). Therefore, these cross-linked waterborne polyurethanes hold great promise for antibacterial applications in vivo.

Progressive Pulmonary Hypertension and Lung Nodules Related to Intravenous Promethazine and Heparin Incompatibility.

SESSION TITLE: Miscellaneous SESSION TYPE: Global Case Report Poster PRESENTED ON: Tuesday, October 31, 2017 at 01:30 PM - 02:30 PM INTRODUCTION: This case describes a patient who had progressive embolic pulmonary hypertension and nodular lung disease related to intravenous heparin and promethazine drug incompatibility. CASE PRESENTATION: A 46-year-old woman with chronic relapsing pancreatitis under the supervision of a pain management specialist used self-administered promethazine injections through an implanted mediport at home. She presented to the hospital with abdominal pain, slowly progressive dyspnea on exertion, and a dry cough. Lab work demonstrated elevated liver function tests and CRP. Her chest x-ray showed borderline cardiomegaly and increased interstitial markings with reticular nodular opacities. CT angiography of the chest was negative for PE, but did confirm widespread poorly marginated small nodular densities as well as mild adenopathy. Bronchoscopy with BAL and wash was non-diagnostic. Her echo demonstrated an RVSP of 64 and a right heart catheter later confirmed moderate pulmonary HTN. Further lab workup for pulmonary HTN was negative. Pulmonary function testing showed restrictive disease with a reactive component. She required oxygen with exertion at discharge and was seen in close outpatient follow up for additional workup. Ten weeks later she was readmitted for symptom management of her severe abdominal pain. She denied any shortness of air or cough at that point in time. Repeat CT of the abdomen prompted chest imaging that demonstrated progressive widespread milliary nodular pattern of both lungs with progressive adenopathy. Echo demonstrated slight worsening of pulmonary hypertension. VATS was completed for surgical lung biopsy and pathology demonstrated an exuberant foreign body type reaction to polarizable amorphous foreign material associated with acute inflammation as well as focal microabscess formation. Cultures and stains for infectious organisms were negative. She denied illicit drug use and careful review of her outpatient medications revealed an in-line incompatibility of her IV heparin flushes and promethazine injections. MicroMedex IV compatibility listed the incompatibility as causing an increase in measured haze or turbidity, particulates and/or color change.1 Additional history was obtained and due to lack of readily available normal saline flushes, she had been using prefilled heparin syringes to flush her mediport after injecting promethazine. She was started on high dose prednisone that was slowly tapered over several months with normalization of her pulmonary hypertension on follow up echo. Follow up CT imaging demonstrated resolution of her adenopathy and improvement but incomplete resolution of her nodular airspace disease. DISCUSSION: The patient had been self-administering IV promethazine for nausea via an implanted port often several times per day. Her insurance company had only authorized a small allotment of prefilled saline syringes per month, but had provided a much larger allotment of prefilled heparin syringes for her to use for line maintenance. Due to this discrepancy, she would often use the more readily available heparin syringes as opposed to saline to flush her line after a promethazine dose. Incompatibility between IV promethazine and heparin led to precipitate formation that then embolized in the pulmonary circulation causing progressive pulmonary hypertension as well as diffuse micronodular airspace disease noted on CT. A progressive inflammatory reaction likely potentiated the progressive nodule growth. Treating the patient with steroids was successful in halting the inflammation and partial reversal of the disease process. Proper education about line maintenance and use of saline flushes prevented ongoing embolization. CONCLUSIONS: This case demonstrated the in-line incompatibility of IV promethazine and heparin had significant embolic effects on the pulmonary circulation. Obtaining a thorough history regarding utilization of home medications ultimately led to the diagnosis. Detailed attention as well as appropriate education and monitoring should be given to patients who self-administer IV medications via mediports. Reference #1: Truven Health Analytics MicroMedex IV compatability checker DISCLOSURE: The following authors have nothing to disclose: David Hasselbacher, Rebecca Parrish, Emma Coronel No Product/Research Disclosure Information

Repair of Bone Defects with Chitosan-Collagen Biomembrane and Scaffold Containing Calcium Aluminate Cement.

Innovative biomaterials can provide a promising new direction for the treatment of bone defects, stimulating a proper repair process, with no damage to adjacent tissues. The purpose of this in vivo study was to evaluate the biocompatibility and the osteoinductive capacity of chitosan-collagen biomembrane and scaffold containing calcium aluminate cement. Eighteen New Zealand white rabbits (Oryctolagus cuniculus) were distributed according to the experimental times of analysis (7, 15 and 30 days). Four bone defects were created in the rabbits calvaria, which were individually filled with the biomembrane, scaffold, blood clot (negative control) and autologous bone (positive control). Histopathological analysis was performed using optical microscope at 32´, 64´, 125´ and 320´ magnifications. Cell response to inflammation and new bone tissue formation was quantified using a score system. The biomembrane group presented greater inflammatory response at 15 days, with significant difference to autologous bone group (p<0.05). There was no statistically significant difference for foreign body type reaction among groups (p>0.05). Concerning new bone formation, linear closure of the defect area was observed more evidently in the group with autologous bone. The scaffold group presented similar results compared with the autologous bone group at 30 days (p>0.05). Both tested biomaterials presented similar biocompatibility compared with the control groups. In addition, the biomembrane and scaffold presented similar osteoinductive capacity, stimulating bone repair process in the course of the experimental time intervals.

Ectopic bone formation by gel-derived bioactive glass-poly-L-lactide-co-glycolide composites in a rabbit muscle model

In this study we aimed to assess the in vivo osteoinductive properties of two composite scaffolds made of PLGA (poly-L-lactide-co-glycolide) and two types of gel-derived bioactive glasses, namely a high silica S2 bioactive glass (S2-PLGA composites) or high lime A2 bioactive glass (A2-PLGA composites). To achieve that, the potential of the composites to induce ectopic bone formation in a rabbit muscle has been examined along with the control PLGA scaffold. Cylinder-like scaffolds of 7 × 3 mm (width × height) were implanted into pouches created in the latissimus dorsi muscle of 18 New Zealand rabbits. The tissue sections were obtained at 6, 12 or 24 weeks post-surgery (six rabbits per each time point) and stained with hematoxylin-eosin. The process of wound healing, the formation of collagen-rich connective tissue and its transition to cartilage were examined by Sirius red and Alcian blue histological stainings. We also performed immunohistochemical verification of the presence of osteoblast- and osteoclast- like cells in the vicinity of the scaffolds. A typical foreign body reaction and wound healing process was observed for all implanted scaffolds. Osteoblast- and osteoclast-like cells were observed in the vicinity of the scaffolds as determined by the immunohistochemical staining for Osteocalcin, BMP-2 and Cathepsin K. Compared to plain PLGA scaffolds, numerous osteoblast-like cells were observed 12 weeks post implantation near the composites and the scaffolds gradually degraded as bone formation proceeded.S2-PLGA and A2-PLGA composites display osteoinductive properties in vivo. Furthermore, they are more effective at inducing ectopic bone formation in a rabbit muscle compared to plain PLGA. Thus these SBG-PLGA composite scaffolds have potential for clinical applications in dental and/or orthopedic-bone tissue engineering.

In vivo toxicological assessment of electrochemically engineered anodic alumina nanotubes: a study of biodistribution, subcutaneous implantation and intravenous injection

Electrochemically engineered anodic alumina nanotubes (AANTs) have recently shown good in vitro biocompatibility. However, in vivo toxicological and pathological studies are required to clarify the bio-safety of this novel nanomaterial. Herein, we present a pioneering pilot toxicity study on AANTs in immune-competent murine models (Balb/c mice, 8 weeks). AANTs were administered by intravenous (IV) injection and subcutaneous (SC) implantation routes considering the future toxicological implications associated with this nanomaterial for potential biomedical applications. AANTs, 736 nm long and 90 nm in outer diameter, were chosen as a nanomaterial model. We demonstrate that IV injected AANTs do not have any effect on the mortality or body weight of these animal models within 28 days at three different doses (20, 50, 100 mg kg-1). The biodistribution of AANTs characterized by fluorescence imaging and inductively coupled plasma revealed the accumulation of AANTs in the liver and spleen after IV injection. When AANTs were injected intravenously, the highest dose of 100 mg kg-1 caused moderate hepatotoxicity, identified by histopathological analysis. The implantation of AANTs subcutaneously and directly under the skin leads to an inflammatory response, which is a typical foreign body reaction. Taken together, this work provides new insights into the toxicity patterns of new nanomaterials such as AANTs and establishes a rationale for the design of functional AANTs for future biomedical applications.

Local biological effects of adipose stromal vascular fraction delivery systems after subcutaneous implantation in a murine model

The aim of this study was to test alginate beads and silk fibroin non-woven mats as stromal vascular fraction delivery systems to support cell implantation for tissue repair and regeneration, through trophic and immunomodulant paracrine signaling. Furthermore, in vivo scaffold biocompatibility was histologically analyzed in a murine model at different time endpoints, with particular focus on construct-induced vascularization and neoangiogenesis. The fibroin mat induced a typical foreign body reaction, recruiting macrophages and giant cells and concurrently promoted neovascularization of the implanted construct. Conversely, alginate beads triggered a more circumscribed, chronic inflammatory reaction, which decreased over time. The combined in vivo implantation of alginate beads and fibroin mat with stromal vascular fraction promoted vascularization and integration of scaffolds into the surrounding subcutaneous environment. The new blood vessel ingrowth should, hopefully, support engineered cell viability and functionality, as well as the transport of soluble bioactive molecules. Due to their neovascularization properties, stromal vascular fraction administration, using alginate or fibroin scaffolds, is a new, promising, cost-effective tissue engineering approach.

Teppanyaki/Hibachi Pneumonitis: An Exotic Cause of Exogenous Lipoid Pneumonia.

Exogenous lipoid pneumonia (ELP) is a rare type of inflammatory lung disease caused by aspiration and/or inhalation of fatty substances and characterized by a chronic foreign body-type reaction to intra-alveolar lipid deposits. The usual clinical presentation occurs with insidious onset of nonspecific respiratory symptoms and radiographic findings that can mimic other pulmonary diseases. Diagnosis of ELP is often missed or delayed as it requires a high index of suspicion and familiarity with the constellation of appropriate history and radiologic and pathologic features. We herein report a case of occupational exposure to tabletop “Teppanyaki” entertainment cooking as a cause of ELP, confirmed by surgical lung biopsies in a 63-year-old Asian woman who worked as a Hibachi-Teppanyaki chef for 25 years.

Histological analysis of autologous fascia graft implantation into the rabbit voice muscle

The ideal approach for the treatment of glottal insufficiency remains a challenge for laryngologists. AimThis experimental study assessed the histological changes and fibrosis caused by autologous fascia lata grafts into the rabbit voice muscle. Study DesignA clinical and experimental study. MethodsA 0.2 × 0.2 cm fragment of autologous fascia lata was grafted into the right voice muscle of 14 adult rabbits. Animals were euthanized 30 or 60 days post-procedure and histology of the excised vocal folds was carried out. ResultsNo extensive edema, necrosis or foreign body-type reaction was observed at any time. No significant inflammatory reaction or fibrosis was seen at 30 or 60 days. ConclusionThe presence of fascia lata in the rabbit voice muscle had no significant influence on inflammation, and does not increase fibrosis. Rabbit voice muscle shows good tolerance to fascia lata grafting.

Clinical use of a three-dimensional tissue marker to target postlumpectomy radiation.

53 Background: A three dimensional bioabsorbable coiled tissue marker has been developed to facilitate targeting for radiation therapy post lumpectomy. Proposed advantages are a) clarified targeting of closest margins to the excised tumor, b) providing a three dimensional structure that allows fibrosis to add volume to contribute to cosmesis, c) aiding in re-excision localization. Our experience has demonstrated the array of clinical findings after placement, the imaging findings over time, and pathologic findings for early and late removal. Methods: Consecutive lumpectomy patients who were candidates for targeted radiation therapy were implanted with the 3-D bioabsorbable marker from May 2014 to June 2015. After informed consent, each of 36 patients were followed to gather clinical, imaging and pathologic findings. Standard breast cancer management decisions were made (NCCN). Patients requiring re-excision were examined for pathologic findings related to the device. Routine imaging with mammography and ultrasound were obtained at 6 and 12 months post lumpectomy. Results: The use of the spiral tissue marker with the fixed array of six titanium clips provided a predictable target for radiation treatments. As the tissue marker was sewn to the closest tumor bed, inadvertent dissection planes caused by oncoplastic techniques could be avoided. Clinically the lumpectomy site was firm/dense in 94% of patients at 3 months (n = 36), but in only 60% at one year (n = 21). Two patients who underwent re-excision for positive margins were guided by the 3-dimensional device. Two patients had removal at one month and at 12 months for reasons unrelated to the tissue marker. Histologic examination demonstrated typical foreign body reaction and organization (fig 1b). Mammography at one year demonstrated marker clips coalescing as the bioabsorbable device dissolves with maintenance of the volume of the cavity in 50% of patients(fig 1c). Cosmetic outcome has been good to excellent measured at 6 and 12 months. Conclusions: Clinical, radiologic and pathologic findings during use of a novel bioabsorbable 3-dimensional tissue marker were presented. A national registry to further define these attributes will soon be started.

In vivo compatibility of graphene oxide with differing oxidation states.

Graphene oxide (GO) is suggested to have great potential as a component of biomedical devices. Although this nanomaterial has been demonstrated to be cytocompatible in vitro, its compatibility in vivo in tissue sites relevant for biomedical device application is yet to be fully understood. Here, we evaluate the compatibility of GO with two different oxidation levels following implantation in subcutaneous and intraperitoneal tissue sites, which are of broad relevance for application to medical devices. We demonstrate GO to be moderately compatible in vivo in both tissue sites, with the inflammatory reaction in response to implantation consistent with a typical foreign body reaction. A reduction in the degree of GO oxidation results in faster immune cell infiltration, uptake, and clearance following both subcutaneous and peritoneal implantation. Future work toward surface modification or coating strategies could be useful to reduce the inflammatory response and improve compatibility of GO as a component of medical devices.