Management of frontal sinus trauma: a retrospective study of surgical interventions and complications.

BACKGROUND: Frontal sinus injuries are relatively rare among facial bone traumas. Without proper treatment, they can lead to fatal intracranial complications, including meningitis or brain abscesses, as well as aesthetic and functional sequelae. The management of frontal sinus injuries remains controversial, with various treatment methods and outcomes being reported. This article describes the clinical characteristics, surgical methods, and outcomes among 17 patients who underwent surgery for frontal sinus injury and related complications. CASE PRESENTATION: We retrospectively included 17 patients who underwent surgery for frontal sinus injury and its related complications at the Kangwon National University Hospital between July 2010 and September 2021. Among them, six underwent simple open reduction and fixation of the anterior wall, eight underwent sinus obliteration, and three underwent cranialization. Two patients who underwent sinus obliteration died due to infection-related complications. The patient who underwent cranialization reported experiencing chronic headache and expressed dissatisfaction regarding the esthetic outcomes of the forehead. Except for these three patients, the other patients achieved satisfactory esthetic and functional recovery. CONCLUSION: Active surgical management of frontal sinus injuries is often required owing to the various complications caused by these injuries; however, several factors, including the fracture type, clinical presentation, related craniomaxillofacial injury, and medical history, should be considered while formulating the treatment plan. Surgical treatment through the opening of the frontal sinus should be actively considered in patients with severely damaged posterior wall fractures and those at risk of developing infection.

Retrobulbar hematoma following the repair of an orbital wall fracture: a case series.

BACKGROUND: Retrobulbar hematoma is a rare complication after the repair of an orbital wall fracture, but the caution is required because the condition can cause blindness. CASE PRESENTATION: In this article, 3 cases of retrobulbar hematoma after the surgical repair of an orbital wall fracture are reported. In the first patient, the permanent loss of vision was involved, while in the second patient, the author was able to prevent loss of vision by performing immediate decompression after definite diagnosis and consulting with an ophthalmologist. In the third patient, there was no surgical treatment involved; he recovered on his own without major sequelae. CONCLUSIONS: Retrobulbar hematoma is a very serious condition that can result in blindness. Thus, when it is recognized, every effort should be made to preserve the patient's vision and prevent blindness.

Submental Intubation in Patients with Complex Maxillofacial Injuries.

Airway management in patients with complex maxillofacial injuries is a challenge to anesthesiologists. Submental intubation is a useful technique that is less invasive than tracheostomy in securing the airways where orotracheal and nasotracheal intubation cannot be performed. This procedure avoids the use of tracheostomy and bypasses its associated morbidities. A flexible and kink-resistant reinforced endotracheal tube with detachable universal connector is commonly used for submental intubation. Herein, we report cases involving submental intubation using a reinforced endotracheal tube with a non-detachable universal connector in patients with complex maxillofacial injuries.

Light-emitting diodes at 830 and 850 nm inhibit melanin synthesis in vitro.

Treatment of hyperpigmentation remains a challenge. Because of the positive effects of low-energy Nd:YAG lasers on the treatment of melasma, it is suggested that laser-like light-emitting diodes (LEDs) can potentially ameliorate hyperpigmentation. We evaluated the effect of seven different LED wavelengths on melanogenesis. LED irradiation at 830 nm (dose-dependent, from 1 to 20 J/cm2) and 850 nm (1 J/cm2) significantly reduced melanin production and tyrosinase expression, not only in a normal human melanocyte monoculture both with and without forskolin stimulation but also in a three-dimensional multiple cell type culture. It reduced melanin content via inactivation of the apoptosis signal-regulating kinase and extracellular signal-regulated kinase 1/2 pathways. The level of phosphorylated cyclic AMP response element-binding protein was also decreased by LED irradiation. Moreover, LED irradiation reduced melanogenesis through decreased expression of tyrosinase family genes (tyrosinase-related protein-1 and 2, and microphthalmia-associated transcription factor). These results indicate that LEDs could potentially be used to treat melanin-overproducing skin conditions.

The cyclic pentapeptide d-Arg3FC131, a CXCR4 antagonist, induces apoptosis of somatotrope tumor and inhibits tumor growth in nude mice.

The interaction between the chemokine stromal cell-derived factor 1 and its receptor CXCR4 plays an important role in GH production and cell proliferation in normal and tumorous pituitary somatotrope cells. Therefore, the chemokine receptor CXCR4 could be an attractive target for antitumor drugs in patients with acromegaly. A synthetic antagonist of CXCR4, cyclic pentapeptide d-Arg3FC131 (c[Gly1-d-Tyr2-d-Arg3-Arg4-Nal5]) significantly inhibited GH production and proliferation of GH3 somatotrope tumor cells in vitro. It also induced apoptosis of GH3 cells through activation of the caspase-3 pathway. Systemic administration of d-Arg3FC131 inhibited the growth of GH3 cell xenografts in immunodeficient nude mice by inducing apoptosis and suppressing the proliferation of tumor cells. These results indicate that d-Arg3FC131 might have potential for the treatment of pituitary tumors producing excess GH in patients with acromegaly.

Effect of {beta}4 integrin knockdown by RNA interference in anaplastic thyroid carcinoma.

BACKGROUND: Integrin α6ß4 is a known tumor antigen; however, its function in different subtypes of thyroid cancer is not known. This study reports that α6ß4 expression is selectively up-regulated in anaplastic thyroid cancer (ATC) cells, the most malignant subtype of human thyroid cancer. MATERIALS AND METHODS: To assess the contribution of α6ß4 in ATC progression, cell proliferation, motility and soft agar assay were performed in vitro and a xenograft tumor growth assay was performed in vivo. RESULTS: Knockdown of ß4 integrin subunit expression by shRNA in ATC cells reduced the proliferation, migration, and anchorage-independent growth of ATC cells in vitro and xenograft tumor growth in vivo. CONCLUSION: These data suggest that integrin α6ß4 contributes to the development of aggressive forms of thyroid cancer with poor prognostic potential, such as ATC, and thus may be a novel therapeutic target for the treatment for this subtype of thyroid cancer.

Functional expression of CXCR4 in somatotrophs: CXCL12 activates GH gene, GH production and secretion, and cellular proliferation.

The interaction of chemokine (C-X-C motif) ligand 12 (CXCL12) and its receptor CXCR4 may play an important role in the regulation of anterior pituitary function. In this study, we investigated the expression of CXCL12 and CXCR4 and their role in normal rat pituitary and GH-producing GH3 tumor cell line. RT-PCR analysis and immunohistochemistry revealed that CXCR4 was expressed in normal rat anterior pituitary and GH3 tumor cells. Double immunofluorescent staining showed the complete colocalization of CXCR4 with GH in rat pituitary, indicating that CXCR4 is specifically expressed in rat somatotrophs. Using rat primary pituitary cell cultures and GH releasing hormone receptor expressing stable GH3 cells (GH3-GHRHR), we evaluated the function of CXCL12 compared with GHRH. CXCL12 stimulated GH gene activation in both primary rat anterior pituitary cells and GH3-GHRHR cells. CXCL12 also stimulated GH secretion from primary rat pituitary cells in a dose-dependant manner. BrdU incorporation was increased in response to CXCL12 addition in GH3 cell culture, indicating CXCL12-induced cell proliferation. CXCL12-dependent phosphorylation of ERK1/2 was also confirmed by western blot analysis, supporting the evidence that MAPK is an intracellular mediator of CXCL12/CXCR4 interaction in GH3 cell proliferation. In conclusion, these results indicate that CXCL12/CXCR4 interaction plays an important role in GH production, secretion, and the proliferation of somatotrophs.

Splice variants of the forkhead box protein AFX exhibit dominant negative activity and inhibit AFXalpha-mediated tumor cell apoptosis.

BACKGROUND: Loss-of-function in the apoptosis-inducing genes is known to facilitate tumorigenesis. AFX (FOXO4), a member of forkhead transcription factors functions as a tumor suppressor and has 2 isoforms, AFXalpha (505 a.a.) and AFXzeta (450 a.a.). In human cancer cells, we identified an N-terminally deleted form of AFXalpha (alpha198-505), translated from a downstream start and 2 short N-terminal AFX proteins (90, and 101 a.a.) produced by aberrant splicing. METHODS AND FINDINGS: We investigated the expression and role of these AFX variants. Cell transduction study revealed that short N-terminal AFX proteins were not stable. Though alpha(198-505) protein expression was detected in the cytoplasm and nucleus, alpha(198-505) expressing cells did not show a nucleocytoplasmic shuttling mediated by PI3 kinase signaling. Whereas, we observed this shuttling in cells expressing either AFXalpha or AFXzeta protein. AFXzeta and alpha(198-505) lost the ability to transactivate BCL6 or suppress cyclin D2 gene expression. These variants did not induce cancer cell death whereas AFXalpha resulted in apoptosis. We found that AFXzeta and alpha(198-505) suppress the AFXalpha stimulation of BCL6 promoter in a dose dependent manner, indicating dominant negative activity. These variants also inhibited AFXalpha induction of apoptosis. CONCLUSIONS: Loss of function by aberrant splicing and the dominant negative activity of AFX variants may provide a mechanism for enhanced survival of neoplastic cells.

Identification of novel allele on the locus 47z (DXYS5) in the Korean population.

Two homogenous sequences of 47z (DXYS5) are located on the X (DXYS5X) and Y (DXYS5Y) chromosomes, and these are known to be useful polymorphic markers for tracing male-specific gene flow such as the migration routes of human populations. Using the 47z/StuI PCR-RFLP system, we found a novel allele which showed two bands, in contrast to the previous two allele types, one band (Y1) and three bands (Y2). This means that copies of PCR products derived from both the DXYS5X and DXYS5Y loci were clearly cut by the StuI enzyme, implying that the DXYS5X locus of the X chromosome is polymorphic. Allelic frequencies examined in 267 male Korean individuals showed that 95.8% had Y1, 3.4% Y2, and 0.8% had the novel allele. Our findings should contribute to a better understanding of genetic polymorphism on X and Y chromosomes, the molecular evolution mechanism of sex chromosomes, and how the migration route of Koreans is related to those of other East Asian populations.