Cerebral venous thrombosis without thrombocytopenia after a single dose of COVID-19 (Ad26.COV2.S) vaccine injection: a case report

Neurological Sciences - The coronavirus pandemic became the hard challenge for the modern global health system. To date, vaccination is the best strategy against Sars-Cov-2-related illness. About 3...     

Reconstruction after skin cancer excision through a dermal induction template: our experience

Dermal substitutes offer alternative approaches for wounds of all thicknesses where sufficient donation sites are not available for self‐grafts. Several dermal substitutes are described in literature. This study included 20 patients treated with a dermal induction template after the removal of malignant skin cancers situated in various parts of the body. The participants were especially aged patients with multiple skin cancers, and complex clinical conditions, often affected by pathologies such as cardiopathy, diabetes mellitus, and hypercholesterolaemia, and receiving pharmacological multi‐therapies, particularly antiplatelets and anticoagulants. In many of these patients, the general complex clinical picture provided significant contraindication for complex reconstructive surgery because of the high risk involved. All patients achieved complete healing about 8 weeks after the first surgery. By using a dermal induction template, it was possible to cover substantial loss of substances without the need of autologous tissue, with smoother and less apparent scar, minor occurrence of hypertrophic and retracted scars, better flexibility of healed skin and therefore a better result from an aesthetic point of view.     

Nano-topography: Quicksand for cell cycle progression?

The 3-D spatial and mechanical features of nano-topography can create alternative environments, which influence cellular response. In this paper, murine fibroblast cells were grown on surfaces characterized by protruding nanotubes. Cells cultured on such nano-structured surface exhibit stronger cellular adhesion compared to control groups, but despite the fact that stronger adhesion is generally believed to promote cell cycle progression, the time cells spend in G1 phase is doubled. This apparent contradiction is solved by confocal microscopy analysis, which shows that the nano-topography inhibits actin stress fiber formation. In turn, this impairs RhoA activation, which is required to suppress the inhibition of cell cycle progression imposed by p21/p27. This finding suggests that the generation of stress fibers, required to impose the homeostatic intracellular tension, rather than cell adhesion/spreading is the limiting factor for cell cycle progression. Indeed, nano-topography could represent a unique tool to inhibit proliferation in adherent well-spread cells.     

Peri-implant bone regeneration with calcium sulfate: a light and transmission electron microscopy case report

BACKGROUND: Calcium sulfate is a simple, biocompatible material with a very long, safe clinical history in several different fields of medicine. It is a rapidly resorbing material that leaves behind calcium phosphate lattice, which promotes bone regeneration. OBJECTIVE: The aim of this study was a histological and ultrastructural evaluation of the tissues in a peri-implant site regenerated with calcium sulfate. MATERIALS AND METHODS: The specimens were processed for observation under light and transmission electron microscopes. RESULTS: In light microscopy, trabecular bone was present. No remnants of calcium sulfate were present. Transmission electron microscopy showed, in the areas of the interface with the implant surface, features of mature bone with many osteocytes. An amorphous layer and/or osteoid seam separated this mature bone from the metal surface. CONCLUSION: The results confirm the high biocompatibility and rapid resorption of calcium sulfate.     

Microvessel density in sinus augmentation procedures using anorganic bovine bone and autologous bone: 3 months results

PURPOSE: This study was an immunohistochemical evaluation of microvessel density (MVD) in sinus augmentation procedures with autologous bone and anorganic bone (Bio-Oss). MATERIALS AND METHODS: Twenty-four patients (14 men and 10 women - mean age of 48 years with a range from 34 to 53 years) participated in this study. All the patients presented a maxillary partial unilateral edentulism involving the premolar/molar areas, with a residual alveolar ridge height of about 4 to 5 mm. Twelve patients received sinus augmentation procedures with 100% autologous bone; 100% Bio-Oss was used in the other 12 patients. Endosseous implants were inserted after a mean period of 3 months. As control, the portions of preexisting subantral bone were used. The mean value of the MVD in control bone was 23.4 +/- 1.3. The mean value of the MVD in the sinuses augmented with autologous bone was 29.0 +/- 2.4. The mean value of the MVD in the sinuses augmented with Bio-Oss was 23.8 +/- 2.2. RESULTS: The statistical analysis showed that the differences of the MVD between control bone and sinuses augmented with Bio-Oss were not statistically significant (P = 0.52), while the difference of the MVD between sinuses augmented with autologous bone and those augmented with Bio-Oss was statistically significant (P = 0.0008). CONCLUSIONS: Autologous bone may act not only as a passive filling material in bone defects but may also release osteogenic growth factors; and particles of autologous bone seem to contain vital osteoprogenitor cells.     

Maspin expression in oral squamous cell carcinoma

Maspin (mammary serine protease inhibitor) is a member of the serpin superfamily of protease inhibitors and it has a role as a tumor suppressor. Maspin has been reported to be important in processes relevant to tumor growth and metastasis such as cell invasion, angiogenesis, and apoptosis. A high expression of maspin was correlated with better rates of survival and absence of nodal metastases in head and neck squamous cell carcinoma. In contrast, some studies have shown that maspin overexpression is correlated with a poor prognosis in pancreatic and ovarian cancers and in lung adenocarcinoma. The aim of this study was an immunohistochemical evaluation of the maspin expression in oral squamous cell carcinoma and thus 89 patients were evaluated. Maspin expression in oral squamous cell carcinoma was significantly associated with the tumor differentiation grade (chi test: P = 0.0318) and the lymph node status (chi test: P < 0.005), but not with the tumor stage (chi test: P = 0.666). Metastatic involvement of lymph nodes was observed more frequently in maspin-negative cases than in tumors with more than 5% of positive cells (P = 0.0024). The present results confirm that maspin expression predicts a better prognosis in oral squamous cell carcinoma and that maspin probably plays a role in tumor progression.     

Germany’s next shutdown—Possible scenarios and outcomes

With the rapid increase of reported COVID‐19 cases, German policymakers announced a 4‐week “shutdown light” starting on November 2, 2020. Applying mathematical models, possible scenarios for the evolution of the outbreak in Germany are simulated. The results indicate that independent of the effectiveness of the current restrictive measures they might not be sufficient to mitigate the outbreak. Repeated shutdown periods or permanently applied measures over the winter could be successful alternatives.     

Peri-implant bone tissues around retrieved human implants after time periods longer than 5 years: a retrospective histologic and histomorphometric evaluation of 8 cases

Only rarely, it is possible to find in the literature histological reports of human retrieved implants, especially after several years of functional loading. These implants can help us in understanding the reactions of peri-implant bone. The aim of this study was to perform a histologic and histomorphometric analysis of the peri-implant tissues behavior and of the bone–titanium interface in titanium dental implants retrieved from patients after time periods longer than 5 years. The archives of the Implant Retrieval Center of the Dental School of the University of Chieti-Pescara, Italy were searched for human dental implants, retrieved after a loading period of more than 5 years. A total of 8 implants were found: 3 of these had been retrieved after 5 years, 1 after 6 years, one after 10 years, 1 after 14 years, 1 after 18 years, 1 after 22 years. Only the bone to implant contact in the three best threads was evaluated. Compact, mature, lamellar bone, with few and small marrow spaces, was present around the implants. Osteons with Haversian canals were present inside some threads, in close proximity to the interface, at both cortical and trabecular regions. Other osteons had a direction perpendicular to the direction of the long axis of the implants. Numerous reversal lines were present. At higher magnification, no gaps or fibrous, connective tissues were present at the interface. The BIC of the three best threads for all implants varied from 94 to 100 %.In conclusion, within the limitations of the present report histology showed that implants with different surfaces all presented the potential to maintain osseointegration over a long period, with a continuous remodeling at the interface, as indicated by the presence of reversal lines.