GRANULOMA PIOGÊNICO EM LÁBIO SUPERIOR: RELATO DE CASO

This article is based at the diagnosis of pyogenic granuloma, which is characterized as a benign simple hyperplastic tumor and has an inflammatory reactive component that increases in size as a connective tissue reaction, forming a repair tissue as a protective mechanism. Clinically, pyogenic granuloma is seen as a red or purplish lesion (similar to the adjacent mucosa), too vascular, with a sessile or pedunculated base, with slow growth, reaching a size that rarely exceeds 2,5 cm, the surface of which can be rough or smooth. It occurs more frequently in adulthood, with a predominance in females (mainly during pregnancy), between the second and seventh life's decades. This aim of this paper is to report a case of pyogenic granuloma on the upper lip of a patient at the FAESA's Dental Clinic.

INTERSTITIAL RENAL NECROSIS SYNDROM OF CALVES

Interstitial renal necrosis syndrom (IRNS) was diagnosed in calves sloughtered in Mosul sloughter house. Gross and microscopical picture of 33 affected animals were described. The lesions were identified according topathomorpholgy of tissue reaction. Two patterns of tissue rections were observed. The lesions of the first pattern showed grossly an oval, greyish white translucent nodules on the surface of kidney. Microscopically, cells like lymphocytes and few plasma cells were aggregated in the interstitial tissue. The lesions of the second pattern comprised grossly a milliary yellowish-white nodules on the surface of the kidney and on cut sectionforming extention in the depth of the renal cortex. Microscopically, the infiltrated cells were mainly neutrophils, macrophages and few lymphocytes, the possible causes of this syndrom was discussed.

The Safety of Micro-Implants for the Brain

Technological advancements in electronics and micromachining now allow the development of discrete wireless brain implantable micro-devices. Applications of such devices include stimulation or sensing and could enable direct placement near regions of interest within the brain without the need for electrode leads or separate battery compartments that are at increased risk of breakage and infection. Clinical use of leadless brain implants is accompanied by novel risks, such as migration of the implant. Additionally, the encapsulation material of the implants plays an important role in mitigating unwanted tissue reactions. These risks have the potential to cause harm or reduce the service of life of the implant. In the present study, we have assessed post-implantation tissue reaction and migration of borosilicate glass-encapsulated micro-implants within the cortex of the brain. Twenty borosilicate glass-encapsulated devices (2 × 3.5 × 20 mm) were implanted into the parenchyma of 10 sheep for 6 months. Radiographs were taken directly post-surgery and at 3 and 6 months. Subsequently, sheep were euthanized, and GFAP and IBA-1 histological analysis was performed. The migration of the implants was tracked by reference to two stainless steel screws placed in the skull. We found no significant difference in fluoroscopy intensity of GFAP and a small difference in IBA-1 between implanted tissue and control. There was no glial scar formation found at the site of the implant’s track wall. Furthermore, we observed movement of up to 4.6 mm in a subset of implants in the first 3 months of implantation and no movement in any implant during the 3–6-month period of implantation. Subsequent histological analysis revealed no evidence of a migration track or tissue damage. We conclude that the implantation of this discrete micro-implant within the brain does not present additional risk due to migration.

Biomimetic Ceramic Composite: Characterization, Cell Response, and In Vivo Biocompatibility

The present study aimed to synthesize biphasic calcium phosphate ceramics (CaPs) composed of β-tricalcium phosphate (β-TCP) and hydroxyapatite (HAp) from the propagated Scleractinian coral and dicalcium phosphate anhydrous using a solid-state reaction followed by heat treatment at a temperature of 1100 °C for 1 h to 7 days. The as-prepared coral and coral-derived biphasic CaPs samples were characterized through scanning electron microscopy, X-ray diffractometry, Fourier transform infrared spectroscopy, and Raman spectroscopy. The cell response of the biphasic CaPs was evaluated by in vitro cytotoxicity assessment using mouse fibroblast (L929) cells. The bilateral femoral defect rabbit model was used to assess the early local reaction of the coral-derived biphasic CaPs bone graft on tissue. The results confirmed that the co-existence of β-TCP and HAp was formed at 1100 °C for 1 h. The ratio of HA/β-TCP increased as the heat-treatment time increased. The coral-derived biphasic CaPs comprising 61% HAp and 39% β-TCP (defined as HT-3) were not cytotoxic. Furthermore, no significant differences in local tissue reaction were observed between the HT-3 sample and autogenous bone. Therefore, the synthesized coral-derived biphasic CaPs is a candidate for bone grafting due to its good biocompatibility.

Ultrasound-triggered on Demand Lidocaine Release Relieves Postoperative Pain

BackgroundSafe and noninvasive on-demand relief is a crucial and effective treatment for postoperative pain because it considers variable timing and intensity of anesthetics. Ultrasound modulation is a promising technique for this treatment because it allows convenient timed and noninvasive controlled drug release.MethodsWe created an ultrasound-triggered lidocaine (Lido) release platform using an amino acid hydrogel functioning as three dimensional (3D) scaffold material (Lido-PPIX@ER hydrogel). Optimal preparation conditions and ultrasound-triggered parameters were evaluated. In the postoperative pain SD rat model, the Lido-PPIX@ER hydrogel or free lidocaine was administered by subcutaneous injection immediately after making the paw incision. Mechanical hypersensitivity was assessed using calibrated von Frey filaments after an individualized (highly variable) ultrasound-triggered process. The safety of the treatment was also evaluated.ResultsThe Lido-PPIX@ER hydrogel allows control of the timing, intensity and duration of lidocaine (Lido) to relieve postoperative pain. The hydrogel releases Lido due to the elevated reactive oxygen species (ROS) levels generated by PPIX under ultrasound triggering. The optimal ultrasound parameter (0.3 W/cm2, 30 s) was chosen for in vitro and in vivo studies. The Lido-PPIX@ER hydrogel (with lidocaine, 5.6 mg/mL) under individualized ultrasound triggering (every 2 h in the first 12 h, every 4 h for the next 36 h, and then every 6 h until 72 h postsurgery) released lidocaine and provided effective analgesia for more than 72 h. Additionally, the withdrawal threshold was higher than that in the control group at all time points measured. The hydrogel showed repeatable and adjustable ultrasound-triggered nerve blocks in vivo, the duration of which depended on the extent and intensity of insonation. On histopathology, no systemic effect or tissue reaction was observed in the ultrasound-triggered Lido-PPIX@ER hydrogel-treated group.ConclusionsThe Lido-PPIX@ER hydrogel with individualized (highly variable) ultrasound triggering is a convenient and effective method that offers timed and spatiotemporally controlled Lido release to manage postoperative pain.

Biocompatibility Analyses of HF-Passivated Magnesium Screws for Guided Bone Regeneration (GBR)

Background: Magnesium (Mg) is one of the most promising materials for human use in surgery due to material characteristics such as its elastic modulus as well as its resorbable and regenerative properties. In this study, HF-coated and uncoated novel bioresorbable magnesium fixation screws for maxillofacial and dental surgical applications were investigated in vitro and in vivo to evaluate the biocompatibility of the HF coating. Methods: Mg alloy screws that had either undergone a surface treatment with hydrofluoric-acid (HF) or left untreated were investigated. In vitro investigation included XTT, BrdU and LDH in accordance with the DIN ISO 10993-5/-12. In vivo, the screws were implanted into the tibia of rabbits. After 3 and 6 weeks, degradation, local tissue reactions and bony integration were analyzed histopathologically and histomorphometrically. Additionally, SEM/EDX analysis and synchrotron phase-contrast microtomography (µCT) measurements were conducted. The in vitro analyses revealed that the Mg screws are cytocompatible, with improved results when the surface had been passivated with HF. In vivo, the HF-treated Mg screws implanted showed a reduction in gas formation, slower biodegradation and a better bony integration in comparison to the untreated Mg screws. Histopathologically, the HF-passivated screws induced a layer of macrophages as part of its biodegradation process, whereas the untreated screws caused a slight fibrous tissue reaction. SEM/EDX analysis showed that both screws formed a similar layer of calcium phosphates on their surfaces and were surrounded by bone. Furthermore, the µCT revealed the presence of a metallic core of the screws, a faster absorbing corrosion front and a slow absorbing region of corroded magnesium. Conclusions: Overall, the HF-passivated Mg fixation screws showed significantly better biocompatibility in vitro and in vivo compared to the untreated screws.

Electrospun Resorbable Drug-eluting Nanofibers Promote Healing of Allograft Tendons

We developed biodegradable drug-eluting nanofibers employing an electrospinning technique, and evaluated their effectiveness on the healing of allograft tendon. Poly-D-L-lactide-glycolide was used as the polymeric material for nanofiber, while doxycycline was selected as the drug for delivery. The in vitro and in vivo drug release profiles were investigated. The biomechanical properties of allograft Achilles tendons repaired using the nanofibers were tested in euthanized rabbits at 2-, 4-, and 6-week time intervals. Histological examination was performed for the evaluation of tissue reaction and tendon healing. The level of postoperative animal activity was also monitored using an animal behavior cage. The experimental results showed that the degradable nanofibers as a vehicle could provide sustained release of doxycycline for over 40 days after surgery with very low systemic drug concentration. Allograft Achilles tendon reconstruction assisted with the drug-loaded nanofibers was associated with better biomechanical properties at 6 weeks post-surgery. In addition, the animals exhibited a better level of activity after surgery. Use of drug-eluting nanofibrous membranes could enhance healing in Achilles tendon reconstruction surgery with allograft.

ALD coated polypropylene hernia meshes for prevention of mesh-related post-surgery complications: An experimental study in animals

In this work, thermal atomic layer deposition (ALD) was used to synthesize vanadium (V)-doped TiO2 thin nanofilm on polypropylene (PP) hernia meshes. Multiple layers of (Al2O3+TiVOx) nano-films were coated on the PP hernia mesh surface to provide a layer with a total thickness of 38 nm to improve its antibacterial properties, thereby, prevent mesh-related post-surgery complications. Highly conformal V-doped TiO2 nanofilm were deposited on PP mesh at a temperature of 85 °C. Rats and rabbits have been used to evaluate the tissue reaction on coated PP hernia meshes and biomechanical testing of the healed tissue. 5 rabbits and 10 rats have been implanted with ALD coated and uncoated (control) PP meshes into the back of rats and abdominal wall of rabbits. Histology of the mesh-adjacent tissues and electron microscopy of the explanted mesh surface were performed to characterize host tissue response to the implanted PP meshes. The effect of V-doped TiO2 coating on a living organism and fibroblast functions and bacterial activities were studied. The present results indicated that ALD coating improves adhesion properties and exhibited enhanced antibacterial activity compared to uncoated PP mesh. It was shown that V-doped TiO2 coatings were highly effective in inhibiting S. aureus and E. coli adhesion and exhibited excellent antibacterial activity. We found that V-doping of TiO2, unlike bare TiO2, allows generated and further procured strong redox reactions which effectively kills bacteria under visible light. We have reported comparative analysis of the use of undoped (bare) TiO2 and V-doped TiO2 as a coating for PP meshes and their action in biological environment and preventing biofilms formation compared with uncoated PP meshes. The PP meshes coated with V-doped TiO2 showed significantly lower shrinkage rates compared with an identical PP mesh without a coating. We have shown that ALD coatings provide non-adhesive and functional (antibacterial) properties.

P040 INFLAMMATORY REACTION TO ALD COATED POLYPROPYLENE MESHES USED FOR HERNIA REPIAR. AN EXPERIMENTAL STUDY IN ANIMALS

Aim The main goal of the present work is to study and ability of Atomic Layer Depostion (ALD) ultra-thin (<100nm) ceramic films on polypropylene (PP) hernia meshes to prevent the mesh-associated infections (post-surgery complications). Material and Methods Three types of ALD nanofilms were examined: Al2O3, TiO2, or TixVyOz. 10 rats and 5 rabbits were used to evaluate the tissue reaction of surface modified PP meshes and for biomechanical (antibacterial, inflammation effect), biocompatibility, and barrier testing of the healed tissue. The ALD coated PP meshes were implanted into rabbits and rats together with uncoated ones. After 10, 20, 30 and 60 days, the hernia meshes with the surrounding soft tissues were removed and fixed for histological and cytological studies. Results The TixVyOz (28nm) film showed enhanced antibacterial activity compare to Al2O3 and TiO2 films. The histology was performed on coated and uncoated PP mesh samples. Conclusions The ALD TixVyOz film helped to avoids formation of rough scar tissue (microscale roughness, which prevents ability biofilm formation) and, reduction of eosinophilic-cell and lymphocytic-cell reactions of the tissues surrounding the mesh, illustrate good integration into the surrounding tissue with minimal inflammatory reaction and minimal adhesions to intra-abdominal structures. The ALD film was highly effective in inhibiting S. aureus and E. coli bacteria adhesion and exhibited excellent biological activity in promoting osteoblastic adhesion. Speculatively, presence of vanadyl (≡V=O:) chemical groups, either on the surface or in the bulk, believe to play a key role in high performance of the TixVyOz compare to TiO2.

IMMUNOPATHOLOGICAL EFFECT OF SENSITIZED TRANSFER FACTOR ON THE ORGANS OF WHITE MICE AGAINST SALMONELLA TYPHI CHALLENGE INFECTION.

In an experimental study to evaluate the immunopathological effect of transfer factor on the reticuloendothelial organs of white mice and their protection against their challenge infection with Salmonella typhi. The results of this study were showed the followings: 1. Transfer factor recipient group: it was showed an early granulomatous lesions in the liver. Reactive hyperplasia in the T cell regions of the spleen and mediastinal lymph node. The early granulomas were persisted during 7th day and slightly regressed on 14th day postinoculation. 2. Infected group with S. typhi: It was showed a multifocal microabscesses consisted of aggregates of neutrophils in the focal area of necrosis, which was evident during 7th day and gradually transform into granulomas on 14th day postinoculation. 3. Transfer factor recipient and challenge infection group: It was showed well developed granulomatous reactions, which indicate an emergence of cellular immunity (delayed type hypersensitivity reaction). These granulomas were more evident on 7th day and slightly regressed on 14th day postinoculation; providing a transfer factor role in tissue reaction and termination of infection.