• The Journal of the Korean dental association
• /
• v.57 no.10
• /
• pp.613-622
• /
• 2019

The vitamin K antagonist (VKA), cumadin, or warfarin, is the only antithrombotic drug that can be orally administered and has excellent effective for decades. However, it is cumbersome to periodically inspect the prothrombin time (PT) order to maintain adequate concentrations that do not cause bleeding, takes a few days to indicate therapeutic effects, gets affected by several factors such as food and drugs etc, and narrow in the therapeutic range. Although recently in development, the non-vitamin K antagonist anticoagulants(NOACs) exhibit a rapid onset of action and have relatively short half- lives compared to Coumadin. Because of these pharmacokinetic properties, it is possible to modify an individual's anticoagulation status quite rapidly, minimizing the period where the anticoagulation activity is therapeutically suboptimal. And the short half -lives of these drug allow for the relatively rapid reduction of their anticoagulation effects. There are currently no published clinical trials specifically assessing the bleeding risks associated with dental procedures for patients taking the NOACs. It is not necessary to interrupt NOAC medication for dental procedures that are likely to cause bleeding, but which have a low risk of bleeding complications. Because the bleeding risk for these procedures is considered to be low, the balance of effects is in favour of continuing the NOAC treatment without modification, to avoid increasing the risk of a thromboembolic event. The patients should be advised to miss(apixaban or dabigatran) or delay(rivaroxaban) a dose of their NOAC prior to dental procedures that are likely to cause bleeding and which have a higher risk of bleeding complications. Because the risk of bleeding complications for these procedures is considered to be higher, the balance effects is in favour of missing or delaying the pretreatment NOAC dose. The interruption is only for a short time to minimize the effect on thromboembolic risk.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.19 no.4
• /
• pp.1022-1026
• /
• 2005

To clarify the toxic effect on cultured neonatal mouse cerebral neurons damaged by ischemia, we examined the cytotoxicity induced by ischemia and the protective effect of antioxidant and AMPA/kainate receptor antagonist against ischemia-induced cytotoxicity on cultured cerebral neurons. For this study, mice were administrated with 20ug/kg cyclothiazide or 50U/kg vitamin E via intraperitoneal injection for 2 hours before ischemic induction. After cell culture for 7 days, cell viability, amount of neurofilament and protein kinase C activity were examined. Ischemia decreased significantly cell viability, amount of neurofilament and the increase of protein kinase C activity in these cultures. In the protective effect, vitamin I showed remarkably the increase of cell viability and amount of neurofilament, and the decrease of protein kinase C activity but, cyclothiazide did not showed any protective effect on ischemia-induced cytotoxicity. From these results, it is suggested that vitamin I is effective in blocking the neurotoxicity induced by ischemia, but cyclothiazide as a AMPA/kainate receptor antagonist is not.

• International Journal of Oral Biology
• /
• v.41 no.4
• /
• pp.191-197
• /
• 2016

The present study was to evaluate effects of vitamin E on intravenous administration of lidocaine-induced antinociception. Experiments were carried out using male Sprague-Dawley rats. Orofacial formalin-induced nociceptive behavioral responses were used as the orofacial animal pain model. Subcutaneous injection of formalin produced significant nociceptive scratching behavior. Intraperitoneal injection of 5 and 10 mg/kg of lidocaine attenuated formalin-induced nociceptive behavior in the 2nd phase, compared to the vehicle-treated group. Intraperitoneal injection of 1 g/kg of vitamin E also attenuated the formalin-induced nociceptive behavior in the 2nd phase, compared to the vehicle-treated group. However, low dose of vitamin E (0.5 g/kg) did not affect the nociceptive behavioral responses produced by subcutaneous injection of formalin. The present study also investigated effects of intraperitoneal injection of both vitamin E and lidocaine on orofacial formalin-induced behavioral responses. Vehicle treatment affected neither formalin-induced behavioral responses nor lidocaine-induced antinociceptive effects. However, intraperitoneal injection of 0.5 g/kg of vitamin E enhanced the lidocaine-induced antinociceptive effects in the 2nd phase compared to the vehicle-treated group. Intraperitoneal injection of naloxone, an opioid receptor antagonist, did not affect antinociception produced by intraperitoneal injections of both vitamin E and lidocaine. These results suggest that treatment with vitamin E enhances the systemic treatment with lidocaine-induced antinociception and reduces side effects when systemically treated with lidocaine. Therefore, the combined treatment with vitamin E and lidocaine is a potential therapeutic for chronic orofacial pain.

• Journal of The Korean Society of Clinical Toxicology
• /
• v.9 no.2
• /
• pp.113-116
• /
• 2011

Superwarfarin, such as brodifacoum, is a highly lethal vitamin K antagonist used as a rodenticide. Brodifacoum has a particularly long half-life in the body, which ranges to several months, and therefore requires prolonged treatment with antidotal vitamin K. We experienced a case whereby an 18-year-old male was presented to the hospital with a severe bleeding disorder. It was discovered that he had ingested brodifacoum rodenticide with intent to commit suicide. Despite continual treatment with vitamin K, the bleeding disorder persisted for several months before he recovered. We report this case with literature review.

• Biomolecules & Therapeutics
• /
• v.6 no.3
• /
• pp.276-282
• /
• 1998

Retinoids regulate a wide variety of biological processes such as cellular proliferation and differentiation in many cell types. They have also shown to stimulate replication of several viruses including human cytomegalovirus (CMV). Retinoid signalling pathway involves two distinct subfamilies of nuclear receptors, retinoic acid receptors (RARs) and retinoid X receptors (RXRs) that bind to specific retinoic acid response elements (RAREs) in the promoter regions of retinoid-target genes. Here, we characterized RAREs in the regulatory regions of the CMV and of the hepatitis B vi.us (HBV). The viral RAREs, i.e., CMV-RARE and HBV-RARE, are composed of two consensus RARE half-sites (A/GGGTCA) arranged as a direct repeat separated by 5-bp and 1-bp, respectively. The RAREs were activated by both RAR/RXR heterodimers and RXR homodimers in transient transfection experiments. We also found that COUP-TF$\alpha$ (chicken ovalbumin upstream promoter-transcription factor u) and COUP-TF$\beta$ repressed the retinoid response of the viral elements. Further we demonstrated that previously known retinoid antagonist, SRI 1330, repressed retinoid-induced transactivation of the CMV-RARE. These results implicate Vitamin A, it's nuclear receptors and COUP-TFs as important regulators of the CMV and HBV pathogenesis and the SRl1330 as potential negative modulator of such retinoid-dependent processes.

• Biomolecules & Therapeutics
• /
• v.25 no.5
• /
• pp.461-470
• /
• 2017

Anticoagulant drugs, like vitamin K antagonists and heparin, have been the mainstay for the treatment and prevention of venous thromboembolic disease for many years. Although effective if appropriately used, traditional anticoagulants have several limitations such as unpredictable pharmacologic and pharmacokinetic responses and various adverse effects including serious bleeding complications. New oral anticoagulants have recently emerged as an alternative because of their rapid onset/offset of action, predictable linear dose-response relationships and fewer drug interactions. However, they are still associated with problems such as bleeding, lack of reversal agents and standard laboratory monitoring. In an attempt to overcome these drawbacks, key steps of the hemostatic pathway are investigated as targets for anticoagulation. Here we reviewed the traditional and new anticoagulants with respect to their targets in the coagulation cascade, along with their therapeutic advantages and disadvantages. In addition, investigational anticoagulant drugs currently in the development stages were introduced.

• The Journal of the Korean dental association
• /
• v.57 no.10
• /
• pp.623-628
• /
• 2019

Warfarin is an anticoagulant involved in the production of vitamin K dependent blood clotting factors. Dentists should be familiar with the appropriate assessment methods and considerations for the treatment of patients taking warfarin. Dental surgery with the moderate risk of bleeding can be performed without stopping the drug through preoperative examination of the INR(international normalized ratio) value and evaluation. When performing a surgery with a high risk of bleeding, it is necessary to evaluate whether the drug can be discontinued, what the duration is, and the risk of discontinuation. Hemostasis can be obtained by local methods in most cases of postoperative bleeding in patients taking appropriately adjusted doses of warfarin.

• Proceedings of the PSK Conference
• /
• 2002.10a
• /
• pp.278.1-278.1
• /
• 2002

In the previous study, we reported that NQ12, a vitamin K antagonist. showed a potent antithrombotic and antiplatelet activities. In order to elucidate the antiplatelet activity of NQ12. we investigated the effect of NQ12 on arachidonic acid cascade parameters such as cPLA2. cyclooxygenase (COX), and the downstream production such as TxA2, PGD2 and 12-HETE. N012 inhibited COX activity in a concentration-dependent manner in U937 cells. (omitted)

• Journal of Chest Surgery
• /
• v.56 no.2
• /
• pp.90-98
• /
• 2023

Background: Atrial fibrillation (AF) is the most common type of cardiac arrhythmia. Totally thoracoscopic ablation (TTA) is a surgical treatment showing a high success rate as a hybrid procedure with radiofrequency catheter ablation to control AF. This study compared the early complications of warfarin and non-vitamin K antagonist oral anticoagulants (NOACs) in patients who underwent TTA. Methods: This single-center retrospective cohort study enrolled patients who underwent planned TTA for AF from February 2012 to October 2020. All patients received postoperative anticoagulation, either with warfarin or a NOAC (apixaban, rivaroxaban, dabigatran, or edoxaban). Propensity score matching was performed for both groups. Early complications were assessed at 12 weeks after TTA and were divided into efficacy and safety outcomes. Both efficacy and safety outcomes were compared in the propensity score-matched groups. Results: Early complications involving efficacy outcomes, such as stroke and transient ischemic attack, were seen in 5 patients in the warfarin group and none in the NOAC group. Although the 2 groups differed in the incidence of efficacy outcomes, it was not statistically significant. In safety outcomes, 11 patients in the warfarin group and 24 patients in the NOAC group had complications, but likewise, the between-group difference was not statistically significant. Conclusion: Among patients who underwent TTA, those who received NOACs had a lower incidence of thromboembolic complications than those who received warfarin; however, both groups showed a similar bleeding complication rate. Using a NOAC after TTA does not reduce efficacy and safety when compared to warfarin.

• Tuberculosis and Respiratory Diseases
• /
• v.75 no.3
• /
• pp.89-94
• /
• 2013

Pulmonary embolism (PE), which can originate as a consequence of deep vein thrombosis (DVT), is the most frequent and potentially fatal venous thromboembolic event. Despite the fact that the incidence of venous thromboembolism (VTE) in Asians is lower than that in the Western populations, a recent epidemiologic study demonstrates an increasing incidence of VTE in the Korean population. Anticoagulants, including low molecular weight heparin (LMWH) and vitamin K antagonist (VKAs), have been the main treatments for PE, however, recently new oral anticoagulants (NOACs) were introduced. We will review how well patients with PE can be managed with the existing anticoagulants and NOACs along with the time span of treatment, which still pose some challenges for clinicians.