Ultrasound-guided selective supraclavicular nerve block for postoperative pain control in children receiving Hickman catheter or chemoport insertion: A randomized controlled trial.

BACKGROUND: Optimal pain management after insertion of a central venous catheter in children remains unclear. AIM: This study aimed to evaluate the effects of a selective supraclavicular nerve block on postoperative analgesia in pediatric patients undergoing hickman catheter or chemoport insertion. METHODS: Fifty patients aged 3-18 years scheduled for elective Hickman or chemoport insertion were randomized into two groups of 25 each: one group received an ultrasound-guided selective supraclavicular nerve block with 0.1 mL/kg of 0.5% ropivacaine (SSCNB group), and the other group did not receive a nerve block (control group). The primary outcome was the postoperative Wong-Baker Faces Pain Rating Scale score measured between 10 and 30 min after surgery. Secondary outcomes included pain scores at 1, 3, and 24 h after the surgery, block-related complications, length of stay in the postanesthesia care unit, postoperative analgesic consumption, and time to first analgesic use 24 h after surgery. RESULTS: The worst pain score within 30 min in the recovery room was significantly lower in the SSCNB group compared to the control group (6 [5-7] vs. 3 [2-4]; median difference, -3; 95% CI, -4 to -1; p < .001). Pain scores at 1, 3, and 24 h after surgery were also significantly lower in the SSCNB group. The need for both opioid and non-opioid analgesics in the postoperative period was significantly lower in the SSCNB group (36.0% vs. 0%; p = .002 and 44.0% vs. 16.0%; mean difference, -28%; 95% CI, -56 to 0.19; p = .033, respectively), while other secondary outcomes were not significantly different between the two groups. CONCLUSIONS: Ultrasound-guided SSCNB is an effective method for managing postoperative pain in children undergoing Hickman catheter or chemoport insertion, reducing the need for analgesics within 24 h after surgery.

Determining optimal positive end-expiratory pressure and tidal volume in children by intratidal compliance: a prospective observational study.

BACKGROUND: Limited data exist regarding optimal intraoperative ventilation strategies for the paediatric population. This study aimed to determine the optimal combination of PEEP and tidal volume (VT) based on intratidal compliance profiles in healthy young children undergoing general anaesthesia. METHODS: During anaesthesia, infants (1 month-1 yr), toddlers (1-3 yr), and children (3-6 yr) were assigned serially to four ventilator settings: PEEP 8 cm H2O/VT 8 ml kg-1 (PEEP8/VT8), PEEP 10 cm H2O/VT 5 ml kg-1 (PEEP10/VT5), PEEP 10 cm H2O/VT 8 ml kg-1 (PEEP10/VT8), and PEEP 12 cm H2O/VT 5 ml kg-1 (PEEP12/VT5). The primary outcome was intratidal compliance profile, classified at each ventilator setting as horizontal (indicative of optimal alveolar ventilatory conditions), increasing, decreasing, or combinations of increasing/decreasing/horizontal compliance. Secondary outcomes were peak inspiratory, plateau, and driving pressures. RESULTS: Intratidal compliance was measured in 15 infants, 13 toddlers, and 15 children (15/43 [35%] females). A horizontal compliance profile was most frequently observed with PEEP10/VT5 (60.5%), compared with PEEP10/VT8, PEEP8/VT8, and PEEP12/VT5 (23.3-34.9%; P<0.001). Decreasing compliance profiles were most frequent when VT increased to 8 ml kg-1, PEEP increased to 12 cm H2O, or both. Plateau airway pressures were lower at PEEP8/VT8 (16.9 cm H2O [2.2]) and PEEP10/VT5 (16.7 cm H2O [1.7]), compared with PEEP10/VT8 (19.5 cm H2O [2.1]) and PEEP12/VT5 (19.0 cm H2O [2.0]; P<0.001). Driving pressure was lowest with PEEP10/VT5 (4.6 cm H2O), compared with other combinations (7.0 cm H2O [2.0]-9.5 cm H2O [2.1]; P<0.001). CONCLUSIONS: VT 5 ml kg-1 combined with 10 cm H2O PEEP may reduce atelectasis and overdistension, and minimise driving pressure in the majority of mechanically ventilated children <6 yr. The effect of these PEEP and VT settings on postoperative pulmonary complications in children undergoing surgery requires further study. CLINICAL TRIAL REGISTRATION: NCT04633720.

Ultrasound-guided esophageal compression during mask ventilation in small children: a prospective observational study.

BACKGROUND: The use of cricoid compression to prevent insufflation remains controversial, and its use in children is limited. This study aimed to examine the effect of real-time ultrasound-guided esophageal compression on the prevention of gastric insufflation. METHOD: This prospective observational study was conducted with fifty children aged < 2 years undergoing general anesthesia. Patients were excluded if they were at an increased risk for gastric regurgitation or pulmonary aspiration. Following anesthetic induction under spontaneous breathing, ultrasound-guided esophageal compression was performed during pressure-controlled face-mask ventilation using a gradual increase in peak inspiratory pressure from 10 to 24 cm H2O to determine the pressure at which gastric insufflation occurred. The primary outcome was the incidence of gastric insufflation during anesthetic induction with variable peak inspiratory pressure after real-time ultrasound-guided esophageal compression was applied. RESULTS: Data from a total of 42 patients were analyzed. Gastric insufflation was observed in 2 (4.7%) patients. All patients except one had their esophagus on the left side of the trachea. Applying ultrasound-guided esophageal compression did not affect the percentage of glottic opening scores (P = 0.220). CONCLUSIONS: The use of real-time ultrasound-guided esophageal compression pressure can aid preventing gastric insufflation during face-mask ventilation in children less than 2 years old. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT04645043.

Central venous catheter-related thrombosis in pediatric surgical patients: A prospective observational study.

BACKGROUND: Perioperative central venous catheters are required but may be associated with various complications. AIMS: The purpose of our study was to assess the incidence and perioperative risk factors for catheter-related internal jugular vein thrombosis in pediatric surgical patients. METHODS: This prospective observational study included children under 6 years of age who were scheduled to undergo central venous catheterization of the right internal jugular vein under general anesthesia. A central venous catheter was inserted under real-time ultrasound guidance. An investigator examined for thrombosis using ultrasonography at predetermined time points. The primary aim was the incidence of catheter-related thrombosis from insertion until the 5th day postoperatively or the removal of the central venous catheter. The secondary aim was the determination of the risk factors for thrombosis. RESULTS: Eighty patients completed the study. Internal jugular vein thrombi were found in 31 patients (38.8%, 95% CI 28.0-49.4). On multiple logistic regression analyses, the number of insertion attempts was the only influencing factor for catheter-related thrombosis (p < .001). More than two insertion attempts increased the risk of thrombosis (odds ratio 5.6; 95% CI 1.7 - 18.7, p = .004). Anesthesia time (p = .017; mean difference 166.4 min; 95% CI 55.7-277.1), intraoperative red blood cell transfusion (p = .001; median difference 21.1 ml kg-1 ; 95% CI 6.6-34.4), and intensive care unit stay (p = .001; median difference 100.0 h; 95% CI 48-311) differed between patients with transient thrombosis and those with thrombosis lasting for more than 3 days. CONCLUSION: Internal jugular vein thrombosis was frequently detected by ultrasound following central venous catheterization in pediatric surgical patients. Multiple insertion attempts may be associated with the incidence of thrombosis. The clinical relevance of thrombi detected via ultrasound surveillance has not been determined.

Performance time of anesthesiology trainees for cricothyroid membrane identification and characteristics of cricothyroid membrane in pediatric patients using ultrasonography.

BACKGROUND: Identifying the cricothyroid membrane is an essential technical skill for front-of-neck access procedures. AIMS: This study evaluated the usefulness of cricothyroid membrane identification in pediatric patients using ultrasonography by anesthesiology trainees without experience in airway ultrasound and collected anatomical data on the cricothyroid membrane and its surrounding airway structures in children. METHODS: This prospective observational study included children aged <18 years scheduled to undergo general anesthesia and anesthesiology trainees who identified the cricothyroid membrane in five sequential anesthetized patients using ultrasonography. A pediatric anesthesiologist confirmed the accuracy of the identified cricothyroid membrane and recorded the performance time. The primary aims were the cricothyroid membrane identification success rate and performance time. The secondary aims were the characterization of the cricothyroid membrane and its surrounding structures. RESULTS: Overall, 150 pediatric patients and 30 anesthesiology trainees were analyzed. The cricothyroid membrane identification success rate using ultrasonography was 100% in all the attempts using a transverse approach. The mean (standard deviation) performance time was 27.2 (18.6) s and 31.0 (23.8) s using the transverse and longitudinal approaches, respectively. The performance time decreased by 3.1 (p = .003, 95% confidence interval [CI] = -5.1--1.0) and 5.2 (p = .007, 95% CI = -8.9--1.4) seconds per increase in number of attempts with the transverse and longitudinal approaches, respectively. The cricothyroid membrane length was mostly correlated with the patients' height (r = .75, p < .001), and the blood vessels surrounding the cricothyroid membrane were observed in 95.9% of the patients. CONCLUSIONS: Anesthesiology trainees without experience in airway ultrasound successfully identified the cricothyroid membrane in pediatric patients using ultrasonography after a brief training period. Further research is required as the identification of a structure does not predict the success of the actual procedure, particularly if done in an emergency situation.

Prediction of fluid responsiveness following liver compression in pediatric patients with single ventricle physiology.

INTRODUCTION: The role of liver compression in predicting fluid responsiveness in children with a single ventricle has never been evaluated. The purpose of this study was to assess whether blood pressure changes during liver compression predict fluid responsiveness in children with single ventricle physiology. METHODS: This prospective, interventional study included children aged 3 months to 5 years who underwent surgery for bidirectional cavopulmonary shunt or extracardiac Fontan operation. Before fluid loading, the right upper abdomen was compressed at 30 mmHg for 10 s, and changes in the blood pressure waves were recorded before administering 10 ml kg-1 of crystalloid solution. Systolic arterial pressure, diastolic arterial pressure, central venous pressure, pleth variability index, respiratory variation in aortic blood flow peak velocity, and stroke volume were measured before and after fluid loading. A volume responder was defined as a patient with >15% increase in stroke volume index. RESULTS: Thirty patients underwent bidirectional cavopulmonary shunt (15 responders and 15 non-responders), and 32 underwent Fontan surgery (17 responders and 15 non-responders). In children with bidirectional cavopulmonary shunt, Δsystolic arterial pressure > 8 mmHg (sensitivity 76.9% and specificity 93.3%), Δdiastolic arterial pressure > 7 mmHg (sensitivity 69.2% and specificity 93.3%), and Δmean arterial pressure > 7 mmHg (sensitivity 69.2% and specificity 100%) during liver compression predicted fluid responsiveness. The areas under the receiver operating characteristic curves of Δsystolic arterial pressure, Δdiastolic arterial pressure, and Δmean arterial pressure were 0.928, 0.859, and 0.874 (all p < .001). In children who underwent Fontan surgery, only Δsystolic arterial pressure > 16 mmHg was predictive of fluid responsiveness (sensitivity of 41.2% and specificity of 100%), with the areas under the receiver operating characteristic curves curve of 0.786 (p < .001). Pleth variability index and respiratory variation in aortic blood flow peak velocity had no predictive value for fluid responsiveness after both types of surgeries. DISCUSSION: In BCPS patients, liver compression increases the inferior vena cava flow which directly leads to an increase in preload. On the other hand, blood flow from the liver drains directly into the pulmonary arteries in Fontan circulation. Because of this characteristics for preload determination, the clinical application of liver compression to monitor hemodynamic changes might be more useful in patients with bidirectional cavopulmonary shunt than those with Fontan circulation. CONCLUSION: Increase in blood pressure induced by liver compression is predictive of fluid responsiveness in children with single ventricle physiology.

Straight-tip guidewire versus J-tip guidewire for central venous catheterisation in neonates and small infants: A randomised controlled trial.

BACKGROUND: Central venous catheterisation in neonates and infants is challenging because of the small size of the vessels. The curve of the J-tip guidewire causes difficulty when inserting because of the larger radius and the tilted angle of the J-tip. OBJECTIVE: We hypothesised that a straight-tip guidewire can facilitate guidewire insertion and improve the first-attempt success rate of central venous catheterisation. DESIGN: A randomised controlled study. SETTING: This study was performed between September 2018 and July 2021 in tertiary care children's hospital. PATIENTS: We enrolled infants weighing less than 5 kg undergoing general anaesthesia. INTERVENTIONS: Patients were randomly allocated to the straight-tip or J-tip groups. Ultrasonography-guided catheterisation was performed using the assigned guidewire. MAIN OUTCOME MEASURES: The primary outcome was the first-attempt success rate of central venous catheterisation. The secondary outcomes included the number of guidewire insertion attempts, the time required for successful guidewire insertion, and total time for central venous catheter placement. RESULTS: Eighty-eight patients were studied. The straight-tip group showed a higher first attempt success rate than the J-tip group (86.3 vs. 61.3%, P  = 0.007, odds ratio 4.0, 95% confidence interval (CI), 1.4 to 11.4]. Guidewire insertion attempts were higher in the J-tip group than in the straight group ( P  = 0.002, odds ratio 9.6, 95% CI, 7.9 to 92.9). Although the guidewire insertion time was longer in the J-tip group ( P  = 0.003, median difference 23.0 s, 95% CI, 7.0 to 48.0), the total catheterisation time was similar owing to the additional guidewire change process in the straight-tip group ( P  = 0.676). CONCLUSION: In neonates or infants weighing less than 5 kg, central venous catheterisation using a flexible straight-tip guidewire can improve the first-attempt success rate compared with a J-tip guidewire. TRIAL REGISTRATION: ClinicalTrials.gov, identifier: NCT03530618.

Validation of the Masimo O3™ regional oximetry device in pediatric patients undergoing cardiac surgery.

We assessed the accuracy of Masimo O3™ regional cerebral oxygen saturation (rSO2) readings by comparing them with reference values and evaluated the relationship between rSO2 and somatic tissue oxygen saturation (StO2) in children undergoing cardiac surgery. After anesthesia induction, pediatric sensors were applied to the forehead and foot sole, and rSO2 and StO2 values were monitored continuously. Before cardiopulmonary bypass (CPB), FIO2 was set to 0.2, 0.5, and 0.8 serially every 15 min. After CPB, FIO2 was reversed. The reference values (SavO2) were calculated by combining arterial (SaO2) and central venous oxygen saturation (SvO2) readings from the arterial and central lines, respectively (0.7 [Formula: see text] SvO2 + 0.3 [Formula: see text] SaO2). In total, 265 pairs of rSO2/StO2 and SavO2 from 49 patients were analyzed. The bias, standard deviation (SD), standard error (SE), and root mean squared error (RMSE) of rSO2 were 2.6%, 4.5%, 0.3%, and 4.3%, respectively. The limits of agreement ranged from -6.3% to 11.6%. Trend accuracy analysis yielded a relative mean error of -1.4%, with an SD of 4.3%, SE of 0.2%, and RMSE of 3.9%. According to multiple linear regression analysis, the application of CPB, FIO2, Hb level, and tip location of the central venous catheter influenced the bias (all P < 0.05). Furthermore, the correlation between rSO2 and StO2 was weak (r = 0.254). rSO2 readings by the Masimo O3™ device and pediatric sensor had good absolute and trending accuracies with respect to the calculated reference values in children undergoing cardiac surgery. rSO2 and StO2 cannot be used interchangeably.Clinical trial registration http://clinicaltrials.gov (number: NCT04208906).

Driving Pressure during Thoracic Surgery: A Randomized Clinical Trial.

WHAT WE ALREADY KNOW ABOUT THIS TOPIC: Driving pressure (plateau minus end-expiratory airway pressure) is a target in patients with acute respiratory distress syndrome, and is proposed as a target during general anesthesia for patients with normal lungs. It has not been reported for thoracic anesthesia where isolated, inflated lungs may be especially at risk. WHAT THIS ARTICLE TELLS US THAT IS NEW: In a double-blinded, randomized trial (292 patients), minimized driving pressure compared with standard protective ventilation was associated with less postoperative pneumonia or acute respiratory distress syndrome. BACKGROUND: Recently, several retrospective studies have suggested that pulmonary complication is related with driving pressure more than any other ventilatory parameter. Thus, the authors compared driving pressure-guided ventilation with conventional protective ventilation in thoracic surgery, where lung protection is of the utmost importance. The authors hypothesized that driving pressure-guided ventilation decreases postoperative pulmonary complications more than conventional protective ventilation. METHODS: In this double-blind, randomized, controlled study, 292 patients scheduled for elective thoracic surgery were included in the analysis. The protective ventilation group (n = 147) received conventional protective ventilation during one-lung ventilation: tidal volume 6 ml/kg of ideal body weight, positive end-expiratory pressure (PEEP) 5 cm H2O, and recruitment maneuver. The driving pressure group (n = 145) received the same tidal volume and recruitment, but with individualized PEEP which produces the lowest driving pressure (plateau pressure-PEEP) during one-lung ventilation. The primary outcome was postoperative pulmonary complications based on the Melbourne Group Scale (at least 4) until postoperative day 3. RESULTS: Melbourne Group Scale of at least 4 occurred in 8 of 145 patients (5.5%) in the driving pressure group, as compared with 18 of 147 (12.2%) in the protective ventilation group (P = 0.047, odds ratio 0.42; 95% CI, 0.18 to 0.99). The number of patients who developed pneumonia or acute respiratory distress syndrome was less in the driving pressure group than in the protective ventilation group (10/145 [6.9%] vs. 22/147 [15.0%], P = 0.028, odds ratio 0.42; 95% CI, 0.19 to 0.92). CONCLUSIONS: Application of driving pressure-guided ventilation during one-lung ventilation was associated with a lower incidence of postoperative pulmonary complications compared with conventional protective ventilation in thoracic surgery.

The angle range of leg abduction with external hip rotation which can minimize femoral artery and vein overlap in pediatric patients.

BACKGROUND: Since the femoral artery frequently overlaps the femoral vein, femoral central venous catheterization carries the risk of arterial puncture in pediatric patients. AIMS: We evaluated the angle range of leg abduction with external hip rotation to minimize the overlap between the femoral artery and vein in pediatric patients undergoing general anesthesia. METHODS: Eighty-two pediatric patients who underwent elective surgery with general anesthesia were enrolled in this study. Using ultrasonography, patients were divided into groups N (patients with non-overlap) and O (patients with continuing overlap) based on the presence of non-overlap range between the femoral artery and vein. The range minimizing the overlap was defined as the range without overlap in group N and as the range presenting the overlap that was less-than-half of the radius of the femoral vein in group O. By increasing the angle of leg abduction with external hip rotation, the starting and ending angles minimizing the overlap were found using ultrasonographic images. RESULTS: The angle range of leg abduction with external hip rotation minimizing the overlap between the femoral artery and vein was defined as the range from the maximum 99% confidence interval of starting angles to the minimum 99% confidence interval of ending angles, which was between 45° and 65° in group N and between 48° and 58° in group O, respectively. CONCLUSION: Positioning patients in a range of 48° and 58° leg abduction with external hip rotation can minimize the overlap between the femoral artery and vein. However, the clinical usefulness of this positioning for femoral venous catheterization remains to be seen.

Impact of Cardiac Rehabilitation Health Insurance Coverage on Cardiac Rehabilitation Use in Korea Using an Interrupted Time Series.

BACKGROUND: Since 2017, the cardiac rehabilitation (CR) program in Korea has been included in the coverage provided by the National Health Insurance to alleviate financial burden. Our study aimed to identify changes in the CR program use according to the implementation of CR coverage. METHODS AND RESULTS: We obtained data from the electronic medical records of a tertiary hospital in Seoul, Korea from January 2014 to February 2020. Data from 2988 patients with acute coronary syndrome who underwent percutaneous coronary intervention were included. To examine the CR use trend among patients undergoing percutaneous coronary intervention, the electronic medical records data of the patients were aggregated quarterly, resulting in a maximum of 24 repeated measures for each patient. Segmented regression is often used to estimate the effects of interventions in an interrupted time series. Policy implementation led to a prompt increase in the probability of CR use (odds ratio [OR], 3.99 [95% CI, 2.89-5.51]). After the implementation of CR coverage, no significant change in CR use (OR, 0.97 [95% CI, 0.92-1.01]) was observed. After percutaneous coronary intervention, more patients opted for CR, especially those receiving education compared with exercise (education: OR, 87.44 [95% CI, 36.79-207.83] versus exercise: OR, 1.99 [95% CI, 1.43-2.76]). CONCLUSIONS: The implementation of CR coverage resulted in a rapid increase in the probability of CR use. Use of the educational program was higher than that of the exercise program. Given the persistently low use of CR, it is imperative to stimulate its adoption by increasing its availability.

Impact of cardiac rehabilitation on cardiovascular event in Korea.

This study aimed to evaluate the effects of cardiac rehabilitation (CR) on major adverse cardiac events (MACE) among patients who underwent PCI procedure. We used data from the electronic medical records (EMR) of a tertiary hospital in Seoul, Korea, from January 2014 to February 2020. Data from 2988 patients who had experienced their first acute coronary syndrome (ACS) and had undergone percutaneous coronary intervention (PCI) were included during the study period. we classified patients into CR participants and non-participants based on their participation in the cardiac rehabilitation (CR) program within 30 days after discharge. And the outcome was the incidence of myocardial infarction (MI) and stroke within 1 year after discharge. The association between participation in CR and risk of developing MACE was evaluated using the Cox proportional hazards model. Patients who achieved CR after undergoing PCI were at a lower risk of developing MI (HR 0.68, CI 0.53-0.86). There was no significant association between participation in CR and the incidence of stroke. Among patients who had more than three stenotic vessels, the risk of developing MI within 1 year of discharge was reduced in CR users compared to non-users (3 or more stenosis vessels: HR 0.55, CI 0.35-0.86). Among patients who used two and more stents during PCI procedures, the risk of developing MI within 1 year of discharge was reduced in CR users compared to non-users (2 and more stents: HR 0.54, CI 0.35-0.85). Among people diagnosed with ACS and receiving PCI, patients who participated in CR within one month of discharge reduced risk of developing MI. Our study reinforced the current evidence on the effect of CR among patients receiving PCI and presented the expansion and enhancement of the CR program.

The effect of dexmedetomidine on neuroprotection in pediatric cardiac surgery patients: study protocol for a prospective randomized controlled trial.

BACKGROUND: Infants undergoing cardiac surgery under cardiopulmonary bypass are vulnerable to postoperative neurodevelopmental delays. Dexmedetomidine has been shown to have protective effects on the heart, kidneys, and brain in animals and adults undergoing cardiac surgery with cardiopulmonary bypass. We hypothesized that dexmedetomidine would have a neuroprotective effect on infants undergoing cardiopulmonary bypass and planned a prospective randomized controlled trial with postoperative neurodevelopment measurements. METHODS: This is a single-center, prospective, double-blinded, randomized controlled trial with 1:1 allocation. A cohort of 160 infants undergoing cardiac surgery with cardiopulmonary bypass will be enrolled. After induction, dexmedetomidine will be infused with a loading dose of 1 µg/kg and a maintenance dose of 0.5 µg/kg/h or the same amount of normal saline will be administered. Upon initiation of cardiopulmonary bypass, an additional dose of dexmedetomidine (0.01 µg/cardiopulmonary priming volume) will be mixed with the cardiopulmonary bypass circuit. The primary outcome will be the proportion of infants who score lower than 85 in any of the cognitive, language, or motor Bayley scales of infant development-III tests 1 year after the surgery. Other feasible outcome measures will include differences in plasma glial fibrillary acidic protein, troponin I, interleukin-6, urinary neutrophil gelatinase-associated lipocalin, and perioperative major adverse events. The results of the Bayley scales of infant development-III test from the study group and the control group will be compared using a chi-squared test under intention-to-treat analysis. A generalized estimating equation will be used to analyze repeated measurements over time. DISCUSSION: This study will enable us to assess whether the use of dexmedetomidine can alter the early neurodevelopmental outcome in infants undergoing cardiac surgery with cardiopulmonary bypass and also estimate effects of dexmedetomidine on other organs. TRIAL REGISTRATION: ClinicalTrials.gov NCT04484922. Registered on 24 July 2020.

A 4 bp deletion mutation in DLX3 enhances osteoblastic differentiation and bone formation in vitro.

A 4 base-pair deletion mutation in the Distal-less 3 (DLX3) gene is etiologic for Tricho-Dento-Osseous syndrome (TDO). A cardinal feature of TDO is an increased thickness and density of bone. We tested the effects of the DLX3 gene mutation responsible for TDO on the osteoblastic differentiation of preosteoblastic MC3T3E1 cells and multipontent mesenchymal C2C12 cells. Differential expression analysis of C2C12 cells transfected with wild type DLX3 or mutant DLX3 was performed and desmin gene expression, an early myoblastic differentiation marker in mesenchymal cells, was evaluated by RT-PCR, western blot analysis, and desmin promoter transcriptional activity. Transfection of wild type DLX3 into MC3T3E1 and C2C12 cells increased alkaline phosphatase-2 activity, mineral deposition, and promoter activities of the osteocalcin and type 1 collagen genes compared to empty vector transfected cells. Transfection of mutant DLX3 into these cells further enhanced alkaline phosphatase activity, mineral deposition, and osteocalcin promoter activities, but did not further enhance type 1 collagen promoter activity. Transfection of mutant DLX3 into C2C12 cells markedly down regulated desmin gene expression, and protein expression of desmin and MyoD, while increasing protein expression of osterix and Runx2. These results demonstrate that the DLX3 deletion mutation associated with TDO enhances mesenchymal cell differentiation to an osteoblastic lineage rather than a myoblastic lineage by changing the fate of mesenchymal cells. This DLX3 mutation also accelerates the differentiation of osteoprogenitor cells to osteoblasts at later stages of osteogenesis.

Antisense inhibition of transglutaminase 2 affects development of mouse embryo submandibular gland in organ culture.

Tissue transglutaminase (TGase 2) has been implicated in numerous cellular functions, i.e., apoptosis, differentiation, extracellular matrix protein cross-linking and organogenesis. Earlier report of the strong transient expression of TGase 2 localized at the anchoring sites of muscle bundles of human embryo and recent findings of a similar transient expression of the TGase 2 in the salivary myoepithelial cells of mouse embryo indicated a definitive role of TGase 2 in the cytodifferentiation of myoepithelial cells. To understand functional role(s) of TGase 2 in the organogenesis of salivary gland, antisense inhibition of TGase 2 expression was performed in the organ culture of mouse embryo submandibular gland. The antisense of TGase 2 transfection tested using oral keratinocyte cell line, KB cells, elicited significant inhibition of cellular transglutaminase expression. The same antisense treatment of submandibular glands in organ culture also resulted in the suppression of cellular TGase 2 expression as indicated by weak immunoreaction against anti-TGase 2 in the myoepithelial cells of submandibular glands in contrast to strong reaction in those of the normal and sense-treated glands. Antisense to TGase 2 treatment induced retarded growth of salivary epithelium in 1 week and severe aberrant growth of salivary ducts and acini in 2 weeks and also expression of apoptotic inducer, Bax specifically localized in the myoepithelial cells, suggesting apoptotic state of myoepithelial cells. These data suggest that the antisense inhibition of TGase 2 expression affects the cytodifferentiation of ductal cells and myoepithelial cells, and resulted in severe retardation of tubuloalveolar structure formation of salivary gland.

Transglutaminase 2 expression in the salivary myoepithelial cells of mouse embryo.

Earlier a strong transient expression of transglutaminase 2 (TGase 2) localized at the anchoring sites of muscle bundles in human embryo was observed. In this study, we report a similar transient expression of the TGase 2 in the salivary myoepithelial cells of mouse embryo by immunohistochemistry, RNA in situ hybridisation, and RT-PCR. From 35 submandibular glands of mouse embryos and postnatal mice, a consistent expression of TGase 2 in the myoepithelial cells via a stage-specific manner was identified by mono-clonal antibody to TGase 2 immunostaining. A similar expression pattern of TGase 2 in the myoepithelial cells was also observed by RNA in situ hybridisation analysis. The expression of TGase 2 in the salivary epithelium and mesenchyme during the prenatal 14.5-15.5 days was found minimally diffusely spread and became intensely focalised in the myoepithelial cells of salivary acini and ducts during the prenatal 16.5-18.5 days but thereafter gradually decreased until postnatal 7 days and remained weak in postnatal 3 weeks. Such transient rise and fall expressions of TGase 2 were also found with the sequential amount of RT-PCR products during the same period. The alpha-smooth muscle actin (alpha-SMA) as a positive control in the myoepithelial cells of mouse submandibular glands was consistently expressed during the prenatal and postnatal period. These results of transient expression of TGase 2 in the myoepithelial cells coincided with the formation of the dendritic basket structure in the periphery of acini and ducts, suggest a possible catalytic role of transglutaminase in a newly formed cellular matrixes during the cytodifferentiating stage of mouse prenatal and neonatal submandibular glands.

Paradoxical effects of elastase inhibitor guamerin on the tissue repair of two different wound models: sealed cutaneous and exposed tongue wounds.

Innate elastase inhibitors are known to be putatively involved in the regulation of tissue inflammation by inhibiting polymorphonuclear leukocyte (PMN) derived proteinases. The aim of this study was to evaluate affects of leukocyte elastase suppression and PMN infiltration on wound healing in mouse by administering the recombinant elastase inhibitor guamerin (rEIG) in two different wound models; 1) impaired pin-punctured dorsal mucosa of anterior tongue wound, 60 mice, treated with saline containing rEIG that were fed ad libitum and 2) stable linear excisional cutaneous wound, 40 mice, covered with fibrin sealant containing rEIG. The progress of healing was analyzed by histological methods. The tongue wounds treated with rEIG became edematous around the pin-punctured tongue wound, and influx of inflammatory cells and PMN into the underlying stromal tissue were seen rapidly after wounding and peaked between 2-4 days. Whereas the control mice showed almost no wheal formation in the pin-punctured wound, a far lesser levels of PMN infiltration, and almost complete wound closure in 4 days. In the other model, the liner excisional cutaneous wound treated with fibrin sealant containing rEIG showed early wound constriction, lesser degree of inflammatory cells influx, and complete reepithelialization in 4-5 days, whereas the wound of control mice with the fibrin sealant alone showed contrary delayed reepithelialization, greater degree of inflammatory cell infiltration, and consequencial formation of greater granulation tissue at wound site. Taken together, these data suggest paradoxical effects of rEIG on the wound healing where in the wound exposed to infiltrating milieu of microorganisms in the oral cavity, the rEIG aggravates the wound healing by interfering with other innate defensive factors and extended greater flux of PMNs to inflamed wound site, while in the wound enclosed by fibrin, the rEIG accelerated wound healing by inhibiting the inflammation-generated proteases and the acute inflammatory reaction.

The Association between Oxidative Stress and Metabolic Syndrome in Adults.

BACKGROUND: In this Study, we investigated the effects of lifestyle and metabolic syndrome on free oxygen radical levels in men and women in Korea. METHODS: A total of 254 adults were included in this study from February 2011 to June 2012 at a health promotion center. Information of the lifestyles and presence of metabolic syndrome factors was obtained. Biochemical markers were measured and free oxygen radicals test (FORT) was performed on the blood. RESULTS: Of the 254 subjects, 86 (33.9%) had metabolic syndrome, and 187 (73.6%) were men. Between the subjects with and without metabolic syndrome, there was a significant increase in alanine aminotransferase and serum FORT values in the subjects with metabolic syndrome. Multiple linear regression analysis showed that high-sensitivity C-reactive protein (hs-CRP) (P = 0.004), metabolic syndrome (P = 0.037), and female gender (P = 0.030) were independent predictors of serum FORT values. The subjects with high fasting blood sugar level or low high density lipoprotein cholesterol levels showed high serum FORT values. CONCLUSION: High hs-CRP, the presence of metabolic syndrome, and female gender were associated with the high oxidative stress. High oxidative stress was associated with the presence of metabolic syndrome.

Clinical and endoscopic predictors of colorectal adenoma recurrence after colon polypectomy.

BACKGROUND/AIMS: Colonic adenoma is a well-known precancerous lesion of colon cancer. Therefore, the early detection of advanced colonic neoplasm is critical. This study aimed to determine whether findings at baseline colonoscopy are independent predictors of subsequent recurrence of adenoma in Korean patients. MATERIALS AND METHODS: Patients who underwent complete colonoscopy ≥2 times at the Seoul Metropolitan Government-Seoul National University, Boramae Medical Center were included. Follow-up colonoscopy was done more than 1 year after removal. Colonoscopic findings at baseline examinations were compared for patients with and without adenoma recurrence. RESULTS: Of the 167 patients enrolled, 78 had recurrent adenoma at follow-up colonoscopy. Male patients had a higher risk of recurrence than female patients. Patients with ≥ 10 mm adenoma at baseline colonoscopy were more likely to have recurrent adenomas than those with < 10 mm adenoma. Patients with ≥4 adenoma at baseline colonoscopy had also an increased risk for recurrent adenomas. Multivariable analysis showed that ≥10 mm sized (Odds ratio 2.76, 95% confidence interval 1.07-7.11, p=0.035) and ≥4 adenomas (Odds ratio 2.58, 95% confidence interval 1.02-6.54, p=0.045) at baseline colonoscopy were independent predictors of adenoma recurrence at subsequent colonoscopy. CONCLUSION: The presence of adenoma ≥10 mm or ≥4 adenomas at baseline colonoscopy were significant predictors of recurrent adenoma.

Assessment of lifestyle effects on the levels of free oxygen radicals in the korean population.

BACKGROUND: As many studies revealed that oxidative stress due to the imbalance of reactive oxygen species (ROS) and antioxidant capacity is related with pathologic processes such as cardiovascular diseases, diabetes, as well as aging and obesity, the relationship between lifestyle and oxidative stress has recently gained much medical attention. However, little information exists on the effects of lifestyle on ROS in Korea. In this study, we investigated the effects of lifestyle on free oxygen radical levels in men and women in Korea. METHODS: A total of 138 adults participated in this study from September 2007 to June 2010 at a health promotion center and department of family medicine. Information on the lifestyle of each participant was obtained by questionnaire. Biochemical markers and a free oxygen radical test (FORT) were also measured. RESULTS: The average age was 47.28 ± 10.85 years and 79.7% were male. High sensitivity C-reactive protein (hs-CRP; r = 0.418, P = 0.012), triglycerides (r = -0.243, P = 0.008), hemoglobin (r = -0.445, P < 0.001), total protein (r = 0.210, P = 0.036), creatinine (r = -0.294, P = 0.001), fruit intake per day (P = 0.047), and smoking (P = 0.003) were related to the FORT levels in univariate analysis. Multiple linear regression analysis showed that hs-CRP (P = 0.039) was an independent predictor of serum FORT values. This statistical model can explain 78% of the variance in FORT values. CONCLUSION: This result suggests that hs-CRP showed a statistically significant positive association with FORT values. Further studies on the relationship between lifestyle and antioxidant capacity as well as ROS seem to be warranted to evaluate the overall effect of oxidative stress.