Comparison of postoperative nausea and vomiting between Remimazolam and Propofol in Patients undergoing oral and maxillofacial surgery: a prospective Randomized Controlled Trial.

BACKGROUND: Remimazolam is a recently approved, ultra-short-acting benzodiazepine. However, few studies have investigated remimazolam in relation to postoperative nausea and vomiting (PONV). This study aimed to compare the effects of remimazolam and propofol on PONV in patients undergoing oral and maxillofacial surgery. METHODS: Patients (n = 206) aged 19-65 years who were scheduled for oral and maxillofacial surgery were randomized into two groups, the remimazolam (R) and propofol group (P). In the R group (n = 94), remimazolam was used to induce anesthesia at 12 mg/kg/h and to maintain anesthesia at 1-2 mg/kg/h. In the P group (n = 95), anesthesia was induced and maintained with propofol (target effect-site concentration: 3-5 µg/ml). In both groups, remifentanil was administered at a target effect-site concentration of 2.5-4 ng/ml. The primary outcome was the overall incidence of PONV during the first 24 h after surgery. Secondary outcomes included the severity of nausea, use of rescue antiemetics, severity of postoperative pain, use of rescue analgesia, and quality of recovery. RESULTS: The incidence of PONV during the first 24 h after surgery was 11.7% and 10.5% in the R group and P group, respectively, and there was no significant difference in the severity of nausea (P > 0.05). Ten patients in the R group and ten patients in the P group required rescue antiemetics during the first 24 h after surgery (P = 0.98). No inter-group differences were observed in terms of postoperative pain score, use of rescue analgesia, and quality of recovery (P > 0.05). CONCLUSIONS: In this study, remimazolam did not increase the incidence and severity of PONV compared with propofol. TRIAL REGISTRATION: KCT0006965, Clinical Research Information Service (CRIS), Republic of Korea. Registration date: 26/01/2022.

Remifentanil reduced the effects of hydrogen peroxide-induced oxidative stress in human keratinocytes via autophagy.

PURPOSE: Excess reactive oxygen species are detrimental to wound repair. Remifentanil decreases reactive oxygen species generation and inflammatory response; however, its effects on oxidative cell injury are not completely understood. Therefore, we investigated the effects of remifentanil on human keratinocytes under hydrogen peroxide-induced oxidative stress and the correlation of these effects with autophagy. MATERIALS AND METHODS: Human keratinocytes (HaCaT cell line) were randomly assigned to four groups: control, hydrogen peroxide, remifentanil pretreatment + hydrogen peroxide, and 3-methyladenine + remifentanil pretreatment + hydrogen peroxide. The MTT assay was performed to analyze cell viability. Apoptotic cell death was measured by Hoechst staining. A scratch assay was used to measure cell migration. The role of autophagy was ascertained by autophagosome staining and western blot analysis of autophagy-related proteins. RESULTS: Compared with the control group, the hydrogen peroxide group showed decreased cell viability, which was improved by remifentanil pretreatment. Hydrogen peroxide-induced apoptotic cell death and delayed cell migration were also improved by remifentanil pretreatment. Western blot analysis showed that the expression of autophagy-related proteins significantly increased in the remifentanil pretreatment + hydrogen peroxide group compared with that in the hydrogen peroxide group. CONCLUSIONS: This study demonstrated that remifentanil pretreatment ameliorates hydrogen peroxide-induced oxidative injury in human keratinocytes. In addition, our results show that the antioxidative effect of remifentanil against hydrogen peroxide-induced oxidative injury was mediated by autophagy.

Effects of Remifentanil Preconditioning on Osteoblasts under Hypoxia-Reoxygenation Condition.

BACKGROUND: Ischemia-reperfusion of bone occurs in a variety of clinical conditions, such as orthopedic arthroplasty, plastic gnathoplasty, spinal surgery, and amputation. Usually, cellular models of hypoxia-reoxygenation reflect in vivo models of ischemia-reperfusion. With respect to hypoxia-reoxygenation conditions, the effects of remifentanil on osteogenesis have received little attention. Therefore, we investigated the effects of remifentanil on the proliferation and differentiation of osteoblasts during hypoxic-reoxygenation. METHODS: After remifentanil (0.1, 1 ng/mL) preconditioning for 2 hours, human osteoblasts were cultured under 1% oxygen tension for 24 hours. Thereafter, the cells were reoxygenated for 12 hours at 37 °C. The naloxone groups were treated with naloxone for 30 minutes before remifentanil treatment. We measured cell viability via MTT assay. Osteoblast maturation was determined by assay of bone nodular mineralization. Quantitative PCR and western blot methods were used to determine BMP-2, osteocalcin, Akt, type I collagen, osterix, TGF-ß1, HIF-1α, and RUNX2 expression levels. RESULTS: Osteoblast viability and bone nodular mineralization by osteoblasts is recovered by remifentanil preconditioning from hypoxia-reoxygenation insult. During hypoxic-reoxygenation condition, remifentanil preconditioning induced the expression of BMP-2, osteocalcin, Akt, type I collagen, osterix, TGF-ß1, HIF-1α, and RUNX2 in osteoblasts. CONCLUSIONS: Under hypoxia-reoxygenation conditions, remifentanil preconditioning enhanced the cell viability and maturation of osteoblasts, and stimulated the expression of proteins associated with osteoblast proliferation and differentiation of the osteoblast. Our results suggest that remifentanil may help in the treatment of bone stress injuries.

Transient ipsilateral mydriasis during correction of left blowout fracture.

Mydriasis, either bilateral or unilateral, seldom occurs during reconstruction of periorbital fracture. Anisocoria, a unilateral mydriasis, requires more urgent assessment than bilateral mydriasis does. Pharmacologic agents, local anesthetic infiltration, as well as direct or indirect oculomotor nerve damage are possible causes of unilateral mydriasis. Few cases have been reported about intraoperative temporary ipsilateral mydriasis during correction of blowout fracture. We have experienced an unusual case of anisocoria and report the case with literature reviews.

Low-level laser therapy induces the expressions of BMP-2, osteocalcin, and TGF-ß1 in hypoxic-cultured human osteoblasts.

The aim of this study was to examine the effect of low-level laser therapy (LLLT) on the cell viability and the expression of hypoxia-inducible factor-1s (HIF-1s), bone morphogenic protein-2 (BMP-2), osteocalcin, type I collagen, transforming growth factor-ß1 (TGF-ß1), and Akt in hypoxic-cultured human osteoblasts. Human fetal osteoblast cells (cell line 1.19) were cultured under 1 % oxygen tension for 72 h. Cell cultures were divided into two groups. At the experimental side, low-level laser (808 nm, GaAlAs diode) was applied at 0, 24, and 48 h. After irradiation, each cell culture was incubated 24 h more under hypoxia. Total energy was 1.2, 2.4, and 3.6 J/cm(2), respectively. Non-irradiated cultures served as controls. Comparisons between the two groups were analyzed by t test; a p value <0.05 was considered statistically significant. Hypoxia resulted in a decrease in the expression of type I collagen, osteocalcin, and TGF-ß1 (p < 0.001, p < 0.001, and p < 0.01, respectively). Cell viability and BMP-2 expression were not decreased by hypoxic condition. On the other hand, LLLT on hypoxic-cultured osteoblast promoted the expression of BMP-2, osteocalcin, and TGF-ß1 (p < 0.05, p < 0.01, and p < 0.001, respectively). Cell proliferation was also increased time-dependently. However, hypoxia decreased in type I collagen expression (p < 0.001), and LLLT did not affect type I collagen expression in hypoxic-cultured osteoblasts. Furthermore, LLLT inhibited HIF-1 and Akt expression in hypoxic conditioned osteoblasts. We concluded that LLLT induces the expression of BMP-2, osteocalcin, and TGF- ß1 in 1 % hypoxic-cultured human osteoblasts.

Effect of nitrous oxide inhalation on pain after propofol and rocuronium injection.

PURPOSE: This prospective, double-blind, placebo-controlled study was designed to determine the efficacy of nitrous oxide (N(2)O) in alleviating the pain that followed sequential injection of propofol and rocuronium. METHODS: A total of 205 adult patients (age, 18-68 years) received one of the following combinations: NaCl and 100 % O(2) (group C); 0.5 mg/kg lidocaine and 100 % O(2) (group L); NaCl and a mixture of 67 % N(2)O/O(2) (group N); or 0.5 mg/kg lidocaine and a mixture of 67 % N(2)O/O(2) (group LN). Vein occlusion was released after 1 min, and 5 ml propofol was injected over 10 s. Pain was evaluated on a visually enlarged, laminated, numeric rating (0-10) scale. The remainder of the induction dose of propofol (with a 3-ml bolus of normal saline and 0.6 mg/kg rocuronium) was then injected. The response to the rocuronium injection was assessed with a four-point scale (0-3). RESULTS: The incidence and severity of pain from the propofol injection in groups L, N, and LN were significantly lower than those in group C (P < 0.001). Frequency and intensity of the withdrawal response were significantly less in groups N and LN than in groups C and L (no response, P < 0.001; severe response, P < 0.001). CONCLUSIONS: Pretreatment with inhaled N(2)O can reduce the pain associated with propofol and rocuronium injection. Moreover, N(2)O (with or without lidocaine) is more effective than lidocaine alone in reducing rocuronium-related withdrawal reactions associated with sequential injection of propofol and rocuronium.

Ketamine-propofol (ketofol) in procedural sedation: a narrative review.

Sedation methods for dental treatment are increasingly explored. Recently, ketofol, which is a combination of ketamine and propofol, has been increasingly used because the advantages and disadvantages of propofol and ketamine complement each other and increase their effectiveness. In this review, we discuss the pharmacology of ketamine and propofol, use of ketofol in various clinical situations, and differences in efficacy between ketofol and other sedatives.

Lidocaine intensifies the anti-osteogenic effect on inflammation-induced human dental pulp stem cells via mitogen-activated protein kinase inhibition.

Background/purpose: Human dental pulp stem cells (hDPSCs) are an emerging source of mesenchymal stem cells (MSCs) for bone tissue regeneration and engineering. In bone regeneration using transplanted MSCs, the extracellular environment or co-injected drugs can affect their success or failure. In this study, we investigated the effects and signaling mechanisms of lidocaine on osteogenic differentiation of hDPSCs after inducing inflammatory conditions with lipopolysaccharide (LPS) and tumor necrosis factor-alpha (TNF-α). Materials and methods: To investigate the effect of lidocaine on the osteogenic differentiation of LPS/TNF-α-treated hDPSCs, alkaline phosphatase (ALP) and Alizarin red S (ARS) staining were conducted. The expression of osteogenesis-related genes was assessed using quantitative real-time polymerase chain reaction and western blotting. The expression of mitogen-activated protein kinases was analyzed to evaluate the effect of lidocaine on osteogenic differentiation of LPS/TNF-α-treated hDPSCs. Results: Various concentrations of lidocaine (0.05, 0.2, and 1 mM) further decreased ALP and ARS staining of LPS/TNF-α-treated hDPSCs. Similarly, the mRNA and protein expression of osteogenesis-related genes was suppressed via lidocaine treatment in LPS/TNF-α-treated hDPSCs. Lidocaine treatment downregulated the protein expression of p-ERK and p-JNK in LPS/TNF-α-treated hDPSCs. Conclusion: Lidocaine intensified the inhibition of osteogenic differentiation on inflammation-induced hDPSCs by inhibiting the ERK and JNK signaling pathways. This in vitro study suggested that lidocaine may have an inhibitory effect on bone regeneration.

Lidocaine inhibits osteogenic differentiation of human dental pulp stem cells in vitro.

OBJECTIVE: Lidocaine is an amide local anaesthetic commonly used for pain control, however, few studies have investigated the effect of lidocaine on the osteogenic differentiation of human dental pulp stem cells (HDPSCs). The present study aimed to determine the effect of lidocaine on HDPSC viability and osteogenic differentiation. METHODS: HDPSCs were incubated with 0, 0.05, 0.2, 0.5, and 1 mM lidocaine for 24, 48 and 72 h, after which, MTT assays were performed. HDPSCs cultured with the above lidocaine concentrations and osteogenic differentiation medium for 7 and 14 days were stained for alkaline phosphatase (ALP). Protein and mRNA levels of relevant osteogenic factors (bone morphogenetic protein-2 [BMP-2] and runt-related transcription factor 2 [RUNX2]) were examined using western blotting and real-time reverse-transcription polymerase chain reaction, respectively. RESULTS: Lidocaine did not affect the viability of HDPSCs, however, lidocaine reduced ALP activity in HDPSCs. Levels of ALP, BMP-2, and RUNX2 mRNA were reduced with lidocaine, and levels of BMP-2 and RUNX2 proteins were decreased, versus controls. CONCLUSIONS: Lidocaine inhibits osteogenic differentiation markers in HDPSCs in vitro, even at low concentrations, without cytotoxicity. This study suggests that lidocaine may inhibit osteogenic differentiation in HDPSC-mediated regenerative medicine, including pulp regeneration and repair.

Hypothermic cardiopulmonary bypass for minimally invasive mitral valve plasty in adult moyamoya disease.

A 43-year-old man underwent minimally invasive mitral valve plasty of a flail mitral valve. Four years previously, he had been diagnosed with moyamoya disease (MMD) by cerebral magnetic resonance imaging/angiography findings. In MMD, risk factors for cerebral stroke include changes in arterial carbon dioxide partial pressure, blood pressure, and body temperature. And during cardiopulmonary bypass (CPB), these hemodynamic changes can be challenging. However, hypothermia during CPB can decrease cerebral oxygen consumption and have a cerebral protective effect. We performed a minimally invasive mitral valve plasty, using hypothermic CPB, in a patient with MMD, without any neurological deficits.

Availability of a 5% lidocaine patch used prophylactically for venipuncture- or injection-related pain in children.

PURPOSE: Venipuncture- or injection-related pain is still major problem during anesthetic induction in children. This study was designed to determine the availability of a 5% lidocaine patch used prophylactically for venipuncture- or injection-related pain during the induction of anesthesia. METHODS: In a randomized, double-blind study, 72 pediatric patients were allocated to one of two groups: pretreatment with a 5% lidocaine patch (Lidoderm(®), Endo Pharmaceuticals, Chadds Ford, PA, USA) (group A) or pretreatment with a placebo patch (group B). Pain severity was evaluated on the Faces, Legs, Activity, Cry, and Consolability Scale (FLACC) during venipuncture, and a 4-point scale during the injection of rocuronium. RESULTS: The FLACC score during venipuncture was significantly lower for group A than group B (p < 0.001). There was no significant difference in the grades of the 4-point scale observed during the injection of rocuronium between groups A and B. No significant adverse effect was noted for the groups. CONCLUSION: Although pretreatment with a 5% lidocaine patch was found to be a safe, effective, and simple method of preventing venipuncture pain in children, this method did not reduce drug injection pain during the induction of anesthesia.

Propofol protects against lipopolysaccharide-induced inflammatory response in human amnion-derived WISH cells.

Background: Nonobstetric surgery is sometimes required during pregnancy, and neck abscess or facial bone fracture surgery cannot be postponed in pregnant women. However, dental surgery can be stressful and can cause inflammation, and the inflammatory response is a well-known major cause of preterm labor. Propofol is an intravenous anesthetic commonly used for general anesthesia and sedation. Studies investigating the effect of propofol on human amnion are rare. The current study investigated the effects of propofol on lipopolysaccharide (LPS)-induced inflammatory responses in human amnion-derived WISH cells. Methods: WISH cells were exposed to LPS for 24 h and co-treated with various concentrations of propofol (0.01-1 µg/ml). Cell viability was measured using the MTT assay. Nitric oxide (NO) production was analyzed using a microassay based on the Griess reaction. The protein expression of cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE 2), p38, and phospho-p38 was analyzed using western blotting. Results: Propofol did not affect the viability and NO production of WISH cells. Co-treatment with LPS and propofol reduced COX-2 and PGE2 protein expression and inhibited p38 phosphorylation in WISH cells. Conclusion: Propofol does not affect the viability of WISH cells and inhibits LPS-induced expression of inflammatory factors. The inhibitory effect of propofol on inflammatory factor expression is likely mediated by the inhibition of p38 activation.

Dexmedetomidine and LPS co-treatment attenuates inflammatory response on WISH cells via inhibition of p38/NF-κB signaling pathway.

Background: Inflammatory dental diseases that occur during pregnancy can cause preterm labor and/or intrauterine growth restriction. Therefore, proactive treatment of dental diseases is necessary during pregnancy. Dexmedetomidine (DEX) is a widely used sedative in the dental field, but research on the effect of DEX on pregnancy is currently insufficient. In this study, we investigated the effects of co-treatment with DEX and lipopolysaccharide (LPS) on inflammatory responses in human amnion-derived WISH cells. Methods: Human amnion-derived WISH cells were treated with 0.001, 0.01, 0.1, and 1 µg/mL DEX with 1 µg/mL LPS for 24 h. Cytotoxicity of WISH cells was evaluated by 3-(4,5-dimethylthiazol)-2,5-diphenyltetrazolium bromide (MTT) assay. The protein expression of cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2), p38, and nuclear factor kappa B (NF-κB) was examined by western blot analysis. The mRNA expression of pro-inflammatory cytokines such as interleukin (IL)-1ß and tumor necrosis factor (TNF)-α was analyzed by real-time quantitative polymerase chain reaction. Results: Co-treatment with DEX and LPS showed no cytotoxicity in the WISH cells. The mRNA expression of IL-1ß and TNF-α decreased after co-treatment with DEX and LPS. DEX and LPS co-treatment decreased the protein expression of COX-2, PGE2, phospho-p38, and phospho-NF-κB in WISH cells. Conclusion: Co-treatment with DEX and LPS suppressed the expression of COX-2 and PGE2, as well as pro-inflammatory cytokines such as IL-1ß and TNF-α in WISH cells. In addition, the anti-inflammatory effect of DEX and LPS co-treatment was mediated by the inhibition of p38/NF-κB activation.

Propofol attenuates odontogenic/osteogenic differentiation of human dental pulp stem cells in vitro.

Background/purpose: Various studies have used stem cells in the field of bone tissue engineering to repair bone defects. Dental pulp stem cells (DPSCs) have multipotent properties and can be acquired in a noninvasive manner; therefore, they are frequently used in experiments in regenerative medicine. The objective of this study was to investigate the odontogenic/osteogenic differentiation of human DPSCs (hDPSCs) using propofol, a widely used intravenous anesthetic agent. Materials and methods: Alkaline phosphatase (ALP) staining was used to investigate the effects of various concentrations of propofol (5, 20, 50 and 100 µM) on the osteogenic differentiation of hDPSCs. Real-time qPCR and Western blot analysis were used to detect the effect of propofol on the expression of odontogenic/osteogenic genes, such as DMP1, RUNX2, OCN, and BMP2. Odontogenic/osteogenic differentiation of hDPSCs was estimated at days 7 and 14. Results: ALP staining of hDPSCs was significantly decreased by propofol treatment. The mRNA expression of DMP1, RUNX2, OCN, and BMP2 decreased after propofol treatment for 14 days. The protein expression of DMP1 and BMP2 was decreased by propofol at days 7 and 14, and that of RUNX2 was decreased by propofol at day 14 only. Conclusion: Propofol attenuated odontogenic/osteogenic differentiation of hDPSCs in vitro. This result suggests that propofol, which is widely used for dental sedation, may inhibit the odontogenic/osteogenic differentiation of hDPSCs.

Anti-inflammatory effect of remifentanil in lipopolysaccharide-stimulated amniotic epithelial cells.

BACKGROUND: Sometimes general anesthesia is required for dental surgery in pregnant women. Facial bone fractures or neck abscess should be treated immediately. Dental surgery, however, creates a stressful situation that can cause inflammation. Inflammatory responses are a well-known major cause of preterm labor and preterm birth. Here we demonstrate the effects of remifentanil on the factors related to preterm labor and its mechanism of action on amniotic-derived epithelial cells (WISH cells). METHODS: WISH cells were exposed to lipopolysaccharide (LPS) for 24 h and co-treated with various concentrations of remifentanil. MTT assays were performed to measure cell viability. To explain the effects of remifentanil on the factors related to inflammation in WISH cells, activation of nuclear factor kappa B (NF-κB) and p38 and the expression of interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, cyclooxygenase (COX)2, and prostaglandin E (PGE)2 were quantified using western blotting and RT-PCR, respectively. RESULTS: Remifentanil did not affect WISH cell viability. In western blot analysis, co-treatment with remifentanil resulted in decreased phosphorylation of NF-κB, and expression of COX2 and PGE2 in LPS-induced inflammation, but the results were statistically significant only at low concentrations. Reduction of IL-1ß and TNF-α expression was also observed with RT-PCR. CONCLUSION: Co-treatment with remifentanil does not affect the viability of WISH cells, but reduces the expression of the factors related to inflammation, which can induce uterine contraction and preterm labor. These findings provide evidence that remifentanil may inhibit uterine contraction and preterm labor in clinical settings.

Effects of remifentanil preconditioning on factors related to uterine contraction in WISH cells.

BACKGROUND: Preterm labor and miscarriage may occur in stressful situations, such as a surgical operation or infection during pregnancy. Pharyngeal and buccal abscess and facial bone fractures are inevitable dental surgeries in pregnant patients. Remifentanil is an opioid analgesic that is commonly used for general anesthesia and sedation. Nonetheless, no study has investigated the effects of remifentanil on amniotic epithelial cells. This study evaluated the effects of remifentanil on the factors related to uterine contraction and its mechanism of action on amniotic epithelial cells. METHODS: Amniotic epithelial cells were preconditioned at various concentrations of remifentanil for 1 h, followed by 24-h lipopolysaccharide (LPS) exposure. MTT assays were performed to assess the cell viability in each group. The effects of remifentanil on factors related to uterine contractions in amniotic epithelial cells were assessed using a nitric oxide (NO) assay, western blot examinations of the expression of nuclear factor-kappa B (NF-κB), cyclooxygenase 2 (COX2), and prostaglandin E2 (PGE2), and RT-PCR examinations of the expression of the proinflammatory cytokines interleukin (IL)-1ß and tumor necrosis factor-alpha (TNF-α). RESULTS: Remifentanil did not affect viability and nitric oxide production of amniotic epithelial cells. Western blot analysis revealed that remifentanil preconditioning resulted in decreased expressions of NF-κB and PGE2 in the cells in LPS-induced inflammation, and a tendency of decreased COX2 expression. The results were statistically significant only at high concentration. RT-PCR revealed reduced expressions of IL-1ß and TNF-α. CONCLUSIONS: Preconditioning with remifentanil does not affect the viability of amniotic epithelial cells but reduces the expression of factors related to uterine contractions in situations where cell inflammation is induced by LPS, which is an important inducer of preterm labor. These findings provide evidence that remifentanil may inhibit preterm labor in clinical settings.

Medical adhesive related skin injury after dental surgery.

An 87-year-old woman was referred for the extraction of residual teeth and removal of tori prior to prosthetic treatment. After surgery under general anesthesia, the surgical tape was removed to detach the bispectral index sensor and the hair cover. After the surgical tape was removed, skin injury occurred on the left side of her face. After epidermis repositioning and ointment application, a dressing was placed over the injury. Her wound was found to have healed completely on follow-up examination. Medical adhesive related skin injury (MARSI) is a complication that can occur after surgery and subjects at the extremes of age with fragile skin are at a higher risk for such injuries. Careful assessment of the risk factors associated with MARSI is an absolute necessity.

Propofol promotes osteoclastic bone resorption by increasing DC-STAMP expression.

BACKGROUND: Propofol is an intravenous anesthetic which has antioxidant effects due to its similarity in molecular structure to α-tocopherol. It has been reported that α-tocopherol increases osteoclast fusion and bone resorption. Here, we investigated the effects of propofol on signaling pathways of osteoclastogenic gene expression, as well as osteoclastogenesis and bone resorption using bone marrow-derived macrophages (BMMs). METHODS: BMMs were cultured with macrophage colony-stimulating factor (M-CSF) alone or M-CSF plus receptor activator of nuclear factor kappa B ligand (RANKL) in the presence of propofol (0-50 µM) for 4 days. Mature osteoclasts were stained for tartrate-resistant acid phosphatase (TRAP) and the numbers of TRAP-positive multinucleated osteoclasts were counted. To examine the resorption activities of osteoclasts, a bone resorption assay was performed. To identify the mechanism of action of propofol on the formation of multinucleated osteoclasts, we focused on dendritic cell-specific transmembrane protein (DC-STAMP), a protein essential for pre-osteoclastic cell fusion. RESULTS: Propofol increased the formation of TRAP-positive multinucleated osteoclasts. In addition, the bone resorption assay revealed that propofol increased the bone resorption area on dentin discs. The mRNA expression of DC-STAMP was upregulated most strongly in the presence of both RANKL and propofol. However, SB203580, a p38 inhibitor, significantly suppressed the propofol/RANKL-induced increase in mRNA expression of DC-STAMP. CONCLUSION: We have demonstrated that propofol enhances osteoclast differentiation and maturation, and subsequently increases bone resorption. Additionally, we identified the regulatory pathway underlying osteoclast cell-cell fusion, which was enhanced by propofol through p38-mediated DC-STAMP expression.

Effect of remifentanil on pre-osteoclast cell differentiation in vitro.

BACKGROUND: The structure and function of bone tissue is maintained through a constant remodeling process, which is maintained by the balance between osteoblasts and osteoclasts. The failure of bone remodeling can lead to pathological conditions of bone structure and function. Remifentanil is currently used as a narcotic analgesic agent in general anesthesia and sedation. However, the effect of remifentanil on osteoclasts has not been studied. Therefore, we investigated the effect of remifentanil on pre-osteoclast (pre-OCs) differentiation and the mechanism of osteoclast differentiation in the absence of specific stimulus. METHODS: Pre-OCs were obtained by culturing bone marrow-derived macrophages (BMMs) in osteoclastogenic medium for 2 days and then treated with various concentration of remifentanil. The mRNA expression of NFATc1 and c-fos was examined by using real-time PCR. We also examined the effect of remifentanil on the osteoclast-specific genes TRAP, cathepsin K, calcitonin receptor, and DC-STAMP. Finally, we examined the influence of remifentanil on the migration of pre-OCs by using the Boyden chamber assay. RESULTS: Remifentanil increased pre-OC differentiation and osteoclast size, but did not affect the mRNA expression of NFATc1 and c-fos or significantly affect the expression of TRAP, cathepsin K, calcitonin receptor, and DC-STAMP. However, remifentanil increased the migration of pre-OCs. CONCLUSIONS: This study suggested that remifentanil promotes the differentiation of pre-OCs and induces maturation, such as increasing osteoclast size. In addition, the increase in osteoclast size was mediated by the enhancement of pre-OC migration and cell fusion.

The effect of tulobuterol patches on the respiratory system after endotracheal intubation.

BACKGROUND: Endotracheal intubation during anesthesia induction may increase airway resistance (Raw) and decrease dynamic lung compliance (Cdyn). We hypothesized that prophylactic treatment with a transdermal ß2-agonist tulobuterol patch (TP) would help to reduce the risk of bronchospasm after placement of the endotracheal tube. METHODS: Eighty-two American Society of Anesthesiologists (ASA) category I or II adult patients showing obstructive patterns were divided randomly into a control and a TP group (n = 41 each). The night before surgery, a 2-mg TP was applied to patients in the TP group. Standard monitors were recorded, and target controlled infusion (TCI) with propofol and remifentanil was used for anesthesia induction and maintenance. Simultaneously, end-tidal carbon dioxide, Raw, and Cdyn were determined at 5, 10, and 15 min intervals after endotracheal intubation. RESULTS: There was no significant difference in demographic data between the two groups. The TP group was associated with a lower Raw and a higher Cdyn, as compared to the control group. Raw was significantly lower at 10 min (P < 0.05) and 15 min (P < 0.01), and Cdyn was significantly higher at 5 min (P < 0.05) and 15 min (P < 0.01) in the TP group. A trend towards a lower Raw was observed showing a statistically significant difference 5 min after endotracheal intubation (P < 0.01) in each group. CONCLUSIONS: Prophylactic treatment with TP showed a bronchodilatory effect through suppressing an increase in Raw and a decrease in Cdyn after anesthesia induction without severe adverse effects.