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The finding that inadequate social support and discomfort in occupational climate is a better predictor of depressive symptoms than organizational injustice in Korea, indicates that the newly developed KOSS has cultural relevance for assessing occupational stress in Korea. Future studies need to understand factors such as "emotional labor" within certain industries where increased risk for depression is observed.

Cosmetic facial filler-related ophthalmic artery occlusion is rare but is a devastating complication, while the exact pathophysiology is still elusive. Cerebral angiography provides more detailed information on blood flow of ophthalmic artery as well as surrounding orbital area which cannot be covered by fundus fluorescein angiography. This study aimed to evaluate cerebral angiographic features of cosmetic facial filler-related ophthalmic artery occlusion patients. We retrospectively reviewed cerebral angiography of 7 patients (4 hyaluronic acid [HA] and 3 autologous fat-injected cases) showing ophthalmic artery and its branches occlusion after cosmetic facial filler injections, and underwent intra-arterial thrombolysis. On selective ophthalmic artery angiograms, all fat-injected patients showed a large filling defect on the proximal ophthalmic artery, whereas the HA-injected patients showed occlusion of the distal branches of the ophthalmic artery. Three HA-injected patients revealed diminished distal runoff of the internal maxillary and facial arteries, which clinically corresponded with skin necrosis. However, all fat-injected patients and one HA-injected patient who were immediately treated with subcutaneous hyaluronidase injection showed preserved distal runoff of the internal maxillary and facial arteries and mild skin problems. The size difference between injected materials seems to be associated with different angiographic findings. Autologous fat is more prone to obstruct proximal part of ophthalmic artery, whereas HA obstructs distal branches. In addition, hydrophilic and volume-expansion property of HA might exacerbate blood flow on injected area, which is also related to skin necrosis. Intra-arterial thrombolysis has a limited role in reconstituting blood flow or regaining vision in cosmetic facial filler-associated ophthalmic artery occlusions.

The promoter of the human thymidine kinase gene contains cis-regulatory elements responsible for its cell-cycle-regulated expression. We report here that a 70-bp region between -133 and -64 is sufficient to confer cell cycle regulation on a heterologous promoter. The 20-bp region between -64 and -83, which contains an inverted CCAAT motif, is important for transcriptional stimulation of this functional unit. The sequence of this CCAAT motif is nearly identical to the consensus sequence for the transcriptional factor CP1. We also examined the specificity and binding activities of cellular factors interacting with the 70-bp fragment.We showed that the cellular factors binding to the 70-bp region are similar during the Gl, S, and G2 phases, suggesting that the cell cycle regulatory activity observed must involve processes other than factor binding to the DNA.The thymidine kinase (TK) gene encodes a cytosolic enzyme of the pyrimidine salvage pathway. This enzyme catalyzes the phosphorylation of thymidine to form thymidine 5'-monophosphate. Its activity is maximal during the onset of DNA synthesis in the mammalian cell cycle (18). In growth-arrested quiescent cells and terminally differentiated postreplicative cells, the TK activity is diminished and the TK gene is transcriptionally repressed (11,29).To understand the mechanism whereby the TK gene is temporally regulated during the cell cycle, the levels of control of the TK gene have been investigated. It has been established that the TK gene is regulated at both the transcriptional and the posttranscriptional levels. With the onset of DNA synthesis, there is a severalfold increase in the rate of transcription of the TK gene (6,32). At the same time, there is a change in the nuclear posttranscriptional processing of TK heterogeneous nuclear RNA (12). The steady-state levels of TK mRNA also increase sharply as the cells enter the S phase (24). Thus, several mechanisms might contribute to the 10-to 20-fold increase in the TK mRNA levels during the DNA synthetic phase of the cell cycle.The direct observation that the TK gene is transcriptionally activated at the border of the G1 and S phases suggests that sequences contained within the promoter of the TK gene might direct the increase in its transcription rate during the cell cycle. To establish the existence of such a sequence, we and others fused the TK promoter sequence to reporter genes such as the neomycin resistance gene (neo) and the chloramphenicol acetyltransferase (CAT) gene and monitored their expression during the cell cycle (17, 33). In both reporter gene systems, cell cycle regulation was observed. These results provide the first evidence that the TK promoter sequence is capable of directing cell cycle regulation of heterologous genes. Deletion analysis revealed that the region important for cell cycle regulation is between -441 and -64 bp from the transcriptional start site. We also demonstrated that this 378-bp TK promoter fragment has * Corresponding author. enhancing activity and can confer cell cy...

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Recent evidence on the transcriptional regulation of the human thymidine kinase (TK) gene raises the possibility that cell-cycle regulatory sequences may be localized within its promoter. A hybrid gene that combines the TK 5' flanking sequence and the coding region of the bacterial neomycin-resistance gene (neo) has been constructed. Upon transfection into a hamster fibroblast cell line K12, the hybrid gene exhibits cell-cycle-dependent expression. Deletion analysis reveals that the region important for cell-cycle regulation is within -441 to -63 nucleotides from the transcriptional initiation site. This region ( -441 to -63) also confers cell-cycle regulation to the herpes simplex virus thymidine kinase (HSVtk) promoter, which is not expressed in a cell-cycle manner. We conclude that the -441 to -63 sequence within the human TK promoter is important for cell-cycle-dependent expression.One approach to understand the control of cell growth on a molecular level is to identify genes whose expression is modulated during the cell cycle and to study the underlying mechanisms of this regulation. The eukaryotic cell cycle has four distinct phases, G1, S, G2, and M (1). There is evidence revealing that several well-studied S-phase-specific genes, such as those encoding the replication-dependent histones, dihydrofolate reductase, and thymidylate synthase, are regulated at multiple control levels (2-4). Recently, it has been shown by DNA-mediated gene transfer that sequences flanking the replication-dependent histone genes can confer transcriptional (5-7) or posttranscriptional control (8) on the heterologous fusion genes, resulting in cell-cycle regulation of their mRNA levels in vivo.Another well-studied cell-cycle-regulated system is the thymidine kinase (TK) gene, which encodes a cytosol enzyme of the pyrimidine salvage pathway catalyzing the phosphorylation of thymidine to form thymidine 5' monophosphate. It has been documented that the activity of the cytosol TK is cell-cycle regulated and the increase in enzyme activity correlates with increases in DNA synthesis (9 (16,17). The implication is that at least part of the determinants of this regulation are contained within the TK mRNA sequence. With the direct demonstration that the half-life of TK mRNA decreases as S phase cells enter quiescence (18), posttranscriptional regulation of the TK transcripts clearly plays an important role in the cell-cycleregulated expression of the TK gene. The less well-understood level of control for the TK gene is at the step of transcriptional regulation. While it has been demonstrated that TK activity is sensitive to actinomycin D (9), the extreme low levels of the TK transcripts and its transient increase of transcriptional activity occurring only at a narrow period at the G1 and S border makes it difficult to directly measure its transcriptional rate. Thus, earlier attempts failed to detect an increase in TK transcriptional activity (19). Highly sensitive techniques have been used to demonstrate that TK gene expression is ...

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