Lipoblastoma Arising in the Head and Neck: A Clinicopathologic Analysis of 20 Cases.

BACKGROUND: Lipoblastomas (LPBs) are benign adipocytic neoplasms believed to recapitulate the development of embryonal fat. METHODS: We investigated the clinicopathologic and immunohistochemical features of 20 lipoblastomas arising in the head and neck in 18 patients. RESULTS: Patients included 6 males and 12 females (1:2 ratio) with age at diagnosis ranging from 4 months to 28 years. Tumors occurred more commonly in the neck (12, 66.7%) and less commonly in the forehead, scalp, and tongue (2, 11.1%). Tumor size ranged from 1.4 to 6.0 cm (median 5.0 cm). Two patients, a 4-month-old female and 3-year-old male, had local recurrence of neck tumors at 4 months and 3 years after excision, respectively. Microscopically, tumors had a lobulated growth pattern and consisted of adipocytes at varying stages of differentiation. In addition to the classical histologic features, lipoma-like and myxoid variants constituted 45% of cases. Metaplastic elements, including brown fat and cartilage, were identified in two cases. CONCLUSIONS: LPBs arising in the head and neck region are not uncommon and occurred at a rate of 9% in our cohort. They should be kept in the differential diagnosis when a fatty tumor is encountered in an older child or occurring at an unusual location.

Clinical Characteristics and Outcomes of Vaccinated VS Non-Vaccinated Critically Ill COVID-19 Patients: Retrospective Observation Study.

Objective: We aim to identify the clinical characteristics and outcome of vaccine breakthrough infection in critically ill COVID-19 patients and to compare the clinical course of disease between vaccinated and non-vaccinated patients. Methods: A retrospective review of all adult patients aged ≥18 years admitted to the ICU in King Fahd Hospital of the University in Saudi Arabia with positive COVID-19 RT-PCR test between the period of January 1st to August 31st, 2021, were included. The recruited patients were grouped in to "vaccinated and non-vaccinated group" based on their immunization status. The demographic data, co-morbidities, modality of oxygen support, ICU length of stay (ICU LOS) and mortality were collected and analyzed. Results: A total of 167 patients were included. Seventy-two patients (43%) were vaccinated. Cardiovascular diseases were higher among the vaccinated group (33.3% vs 12.6%, p value <0.001). Requirements of Non-invasive ventilation was significantly lower in vaccinated group compared to non-vaccinated group (73.6% vs 91.6%, p value <0.011). The rates of intubation were similar between both groups. The total intubation days was longer in non-vaccinated patients compared to vaccinated patients and the median duration of intubation was 8 days vs 2 days, respectively (p value 0.027). In subgroup analysis, the P/F ratio was significantly higher in patients who received two doses of vaccine compared to single dose (p value <0.002). Conclusion: In critically ill COVID-19 patients, the vaccinated group has significantly less need for Non-invasive ventilation, fewer intubation days and less hypoxia compared to non-vaccinated patients. We recommend more policies and public education nationwide and worldwide to encourage vaccination and raise awareness of the general population.

Expansion of the sagittal suture induces proliferation of skeletal stem cells and sustains endogenous calvarial bone regeneration.

In newborn humans, and up to approximately 2 y of age, calvarial bone defects can naturally regenerate. This remarkable regeneration potential is also found in newborn mice and is absent in adult mice. Since previous studies showed that the mouse calvarial sutures are reservoirs of calvarial skeletal stem cells (cSSCs), which are the cells responsible for calvarial bone regeneration, here we hypothesized that the regenerative potential of the newborn mouse calvaria is due to a significant amount of cSSCs present in the newborn expanding sutures. Thus, we tested whether such regenerative potential can be reverse engineered in adult mice by artificially inducing an increase of the cSSCs resident within the adult calvarial sutures. First, we analyzed the cellular composition of the calvarial sutures in newborn and in older mice, up to 14-mo-old mice, showing that the sutures of the younger mice are enriched in cSSCs. Then, we demonstrated that a controlled mechanical expansion of the functionally closed sagittal sutures of adult mice induces a significant increase of the cSSCs. Finally, we showed that if a calvarial critical size bone defect is created simultaneously to the mechanical expansion of the sagittal suture, it fully regenerates without the need for additional therapeutic aids. Using a genetic blockade system, we further demonstrate that this endogenous regeneration is mediated by the canonical Wnt signaling. This study shows that controlled mechanical forces can harness the cSSCs and induce calvarial bone regeneration. Similar harnessing strategies may be used to develop novel and more effective bone regeneration autotherapies.

Impact of Educational Program on Critical Care Nurses' Knowledge of ICU Delirium: A Quasi-Experimental Study.

Background: Cat Intensive care unit (ICU) delirium is a significant complication that increases the mortality, morbidity, and length of stay for critically ill patient. Objective: The aim of this study was to assess the critical care nurse's knowledge of ICU delirium and the effectiveness of an educational program about the recognition and assessment of ICU delirium on critical care nurse's knowledge. Methods: A quasi-experimental single group pre-test-post-test design was conducted using delirium knowledge assessment questionnaires. Results: The median post test score of overall nurses' knowledge was 76.2 (range 19.1-95.2) compared to the median pre-test score of 38.1 (range 14.3 - 61.9) indicating a significant change in nurses' knowledge after conducting the educational program (p<0.001). Conclusion: Critical care nurses' knowledge of ICU delirium was low before the intervention and increased significantly after delivering an educational program.

A Bronchogenic Cyst Masquerading as a Tongue Mass.

Bronchogenic cysts are foregut-derived developmental anomalies found along the developmental pathway of the foregut. The putative theory of pathogenesis is abnormal budding or branching of epithelial cells during the development of tracheobronchial tree. Over 99 % of cases occur in the mediastinum and lung while the head and neck area is affected in less than 1 % of cases with only rare cases reported in the oral cavity. This is a report of a case of a bronchogenic cyst arising in a 6-year-old male. The lesion presented as a painless swelling of the left underside of the tongue. Microscopically, the cyst was lined by pseudostratified columnar epithelium exhibiting many ciliated and mucous cells. A focus of cartilage and discontinuous bundles of smooth muscle were present adjacent to the lining. Where there was cyst rupture, there was granulation tissue associated with many foamy macrophages and acute and chronic inflammation. Four other cases, three in the tongue and one in the lower lip vestibule with cutaneous extension, all in the midline, have been reported in a 1 day-old male, 4 year-old male, 6 year-old female and 3 year-old male. There was no recurrence after excision and this is in keeping with the behavior in previous reports. Other developmental cysts including foregut cysts may be focally lined with respiratory epithelium but the presence of cartilage is the sine qua non for the diagnosis of a bronchogenic cyst.

Calcifying synovial sarcoma of the tongue with SS18 rearrangement: a rare variant in a rare location.

Synovial sarcoma is a soft tissue malignancy harboring t(X;18) resulting in fusion of two genes SS8 (at 18q11) and SSX (1, 2 or 4 at Xp11) forming the gene fusion product SS18-SSX. It affects adults in their 3rd-4th decades, most frequently in the para-articular regions of the extremities. Less than 10% of the cases occur within the head and neck region and of these, 60% occur in the neck and only 10% occur in the oral cavity. We report a synovial sarcoma of the tongue in a 14-year-old female patient with unusual histology. The patient presented with a mass occupying most of the tongue with extension into the floor of mouth and the lingual gingiva of the anterior mandibular teeth. The tumor was composed of a highly cellular proliferation of spindle cells in a herringbone pattern with many small vessels but without glandular structures, and with extensive calcifications throughout the tumor. Tumor cells were positive for epithelial membrane antigen and transducin-like enhancer of split-1, and fluorescence in situ hybridization studies identified SS18 gene rearrangement. The patient was managed with two debulking procedures followed by chemoradiation and is currently alive with disease.

An Antimicrobial Dental Light Curable Bioadhesive Hydrogel for Treatment of Peri-Implant Diseases.

Dental implants constitute the standard of care to replace the missing teeth, which has led to an increase in the number of patients affected by peri-implant diseases (PIDs). Here, we report the development of an antimicrobial bioadhesive, GelAMP, for the treatment of PIDs. The hydrogel is based on a visible light-activated naturally-derived polymer (gelatin) and an antimicrobial peptide (AMP). The optimized formulation of GelAMP could be rapidly crosslinked using commercial dental curing systems. When compared to commercial adhesives, the bioadhesives exhibited significantly higher adhesive strength to physiological tissues and titanium. Moreover, the bioadhesive showed high cytocompatibility and could efficiently promote cell proliferation and migration in vitro. GelAMP also showed remarkable antimicrobial activity against Porphyromonas gingivalis. Furthermore, it could support the growth of autologous bone after sealing calvarial bone defects in mice. Overall, GelAMP could be used as a platform for the development of more effective therapeutics against PIDs.

Prx1 Expressing Cells Are Required for Periodontal Regeneration of the Mouse Incisor.

Previous studies have shown that post-natal skeletal stem cells expressing Paired-related homeobox 1 (PRX1 or PRRX1) are present in the periosteum of long bones where they contribute to post-natal bone development and regeneration. Our group also identified post-natal PRX1 expressing cells (pnPRX1+ cells) in mouse calvarial synarthroses (sutures) and showed that these cells are required for calvarial bone regeneration. Since calvarial synarthroses are similar to dentoalveolar gomphosis (periodontium) and since there is no information available on the presence or function of pnPRX1+ cells in the periodontium, the present study aimed at identifying and characterizing pnPRX1+ cells within the mouse periodontium and assess their contribution to periodontal development and regeneration. Here we demonstrated that pnPRX1+ cells are present within the periodontal ligament (PDL) of the mouse molars and of the continuously regenerating mouse incisor. By means of diphtheria toxin (DTA)-mediated conditional ablation of pnPRX1+ cells, we show that pnPRX1+ cells contribute to post-natal periodontal development of the molars and the incisor, as ablation of pnPRX1+ cells in 3-days old mice resulted in a significant enlargement of the PDL space after 18 days. The contribution of pnPRX1+ cells to periodontal regeneration was assessed by developing a novel non-critical size periodontal defect model. Outcomes showed that DTA-mediated post-natal ablation of pnPRX1+ cells results in lack of regeneration in periodontal non-critical size defects in the regeneration competent mouse incisors. Importantly, gene expression analysis of these cells shows a profile typical of quiescent cells, while gene expression analysis of human samples of periodontal stem cells (PDLSC) confirmed that Prx1 is highly expressed in human periodontium. In conclusion, pnPRX1+ cells are present within the continuously regenerating PDL of the mouse incisor, and at such location they contribute to post-natal periodontal development and regeneration. Since this study further reports the presence of PRX1 expressing cells within human periodontal ligament, we suggest that studying the mouse periodontal pnPRX1+ cells may provide significant information for the development of novel and more effective periodontal regenerative therapies in humans.

Postnatal Calvarial Skeletal Stem Cells Expressing PRX1 Reside Exclusively in the Calvarial Sutures and Are Required for Bone Regeneration.

Post-natal skeletal stem cells expressing PRX1 (pnPRX1+) have been identified in the calvaria and in the axial skeleton. Here we characterize the location and functional capacity of the calvarial pnPRX1+ cells. We found that pnPRX1+ reside exclusively in the calvarial suture niche and decrease in number with age. They are distinct from preosteoblasts and osteoblasts of the sutures, respond to WNT signaling in vitro and in vivo by differentiating into osteoblasts, and, upon heterotopic transplantation, are able to regenerate bone. Diphtheria toxin A (DTA)-mediated lineage ablation of pnPRX1+ cells and suturectomy perturb regeneration of calvarial bone defects and confirm that pnPRX1+ cells of the sutures are required for bone regeneration. Orthotopic transplantation of sutures with traceable pnPRX1+ cells into wild-type animals shows that pnPRX1+ cells of the suture contribute to calvarial bone defect regeneration. DTA-mediated lineage ablation of pnPRX1+ does not, however, interfere with calvarial development.