Clinical Implications of Heart Rate Control in Heart Failure With Atrial Fibrillation: Multi-Center Prospective Observation Registry (CODE-AF Registry)

Background

Atrial fibrillation (AF) is treated by heart rate (HR) control. However, the optimal HR target in AF patients with heart failure (HF) remains unclear. To evaluate the clinical implication of the resting HR in AF patients with HF accompanied by preserved, mid-range, or reduced ejection fraction (HFpEF, HFmrEF, or HFrEF, respectively).

Methods

Echocardiographic data from June 2016 to April 2020 in a prospective, multicenter, observational registry from 11,104 patients were analyzed. The follow-up duration was 2.2 years. The main outcome was composite of death and hospitalization. We categorized patients according to the HF type and resting HR: ≤ 60 bpm, 61–80 bpm, 81–110 bpm, and >110 bpm.

Results

A total of 1,421 patients were enrolled in the study: 582 in the HFpEF group, 506 in the HFmrEF group, and 333 in the HFrEF group. The patients had a mean age of 69 ± 11 years and consisted of 872 (61.4%) men. Primary endpoint rates among HFpEF patients with 60 < HR ≤ 110 bpm were lower than those with HR ≤ 60 bpm (61–80 bpm group: hazard ratio, 0.66; 95% CI, 0.46–0.94; p = 0.021; 81–110 bpm group: hazard ratio, 0.60; 95% CI, 0.40–0.90; p = 0.013). Especially, HFpEF patients with HR 81–110 bpm had a lower incidence of hospitalization caused by HF aggravation than those with other HR strata (HR ≤ 80bpm strata or HR >110 bpm strata). In HFmrEF and HFrEF patients, the survival rates did not differ significantly among patients in the three groups with HR ≤ 110 bpm. Moreover, the event rates increased significantly in HFmrEF patients with HR >110 bpm (hazard ratio, 1.91; 95% CI, 1.16-3.14, p = 0.011).

Conclusion

In patients with AF and HFpEF, the resting HR has U-shaped associations with the overall primary endpoint. A lower or higher resting HR is associated with increased cardiovascular outcomes, especially in patients with HFpEF and AF.

Calciphylaxis in uraemic and nonuraemic settings: clinical risk factors and histopathological findings

BACKGROUND

Calciphylaxis is a life-threatening cutaneous ulcerative/necrotic disease characterized by vascular calcification/occlusion. It occurs most commonly in end-stage kidney disease (ESKD), known as uraemic calciphylaxis (UC) but can also occur in patients with chronic kidney disease (CKD) and normal kidney function (nonuraemic calciphylaxis; NUC). There are few large series of NUC in the literature.

AIM

To compare the clinicopathological features of UC and NUC.

METHODS

We retrospectively compared the clinicopathological features of 35 patients with NUC during the period 2010-2020 with those of 53 patients with UC (control group). Cases were classified as NUC in the absence of all of the following: ESKD, significant CKD (defined as serum creatinine > 3 mg/dL or creatinine clearance < 15 mL/min) and acute kidney injury requiring kidney replacement therapy or kidney transplantation.

RESULTS

NUC represented 40% of the total cases, and there was a higher number of women (P < 0.01) and a higher median body mass index (P = 0.06) compared with the control UC group. Elevated parathyroid hormone was present in 44% of patients with NUC. Most of the tested patients were positive for lupus anticoagulants (56%). NUC biopsies showed a higher rate of extravascular calcium deposits (73% vs. 47%, P = 0.03). Dermal reactive vascular proliferation was the most common dermal change (32%).

CONCLUSIONS

NUC is more common than previously reported and shows a higher predilection for obese postmenopausal women. Undiagnosed hyperparathyroidism shows a possible association with NUC. Lupus anticoagulants were positive in most patients. NUC biopsies are more likely than UC biopsies to display extravascular calcium deposition.

Catheter ablation of atrial fibrillation in Korea: results from the Korean Heart Rhythm Society Ablation Registry for Atrial Fibrillation (KARA)

Background

This study aims to investigate the current status of AF (atrial fibrillation) catheter ablation in Korea.

Methods

The patients who underwent AF catheter ablation from September 2017 to December 2019 were prospectively enrolled from 37 arrhythmia centers. Demographic data, procedural characteristics, the extent of catheter ablation, acute success of the ablation lesion set, rate and independent risk factor for recurrence of AF were analyzed.

Results

A total of 2402 AF patients [paroxysmal AF (PAF) 45.7%, persistent AF (PeAF) 43.1% and redo AF 11.2%] were included. Pulmonary vein isolation (PVI) was performed in 2378 patients (99%) and acute success rate was 97.9%. Additional non-PV ablation (NPVA) were performed in 1648 patients (68.6%). Post-procedural complication rate was 2.2%. One-year AF-free survival rate was 78.6% and the PeAF patients showed poorer survival rate than the ones with other types (PeAF 72.4%, PAF 84.2%, redo AF 80.0%). Additional NPVA did not influence the recurrence of AF in the PAF patients (PVI 17.0% vs. NPVA 14.6%, P value 0.302). However, it showed lower AF recurrence rate in the PeAF patients (PVI 34.9% vs. NPVA 24.4%, P value 0.001). Valvular heart disease, left atrial diameter, PeAF, PVI alone, need of NPVA for terminating AF, and failed ablation were independent predictors of AF recurrence.

Conclusions

Additional NPVA was associated better rhythm outcome in the patients with PeAF, not in the ones with PAF. The independent risk factors for AF recurrence in Korean population were similar to previous studies. Further research is needed to discover optimal AF ablation strategy.

Weaning of Veno-venous Bypass in Liver Transplantation: A Single Center Experience

BACKGROUND

Veno-venous bypass (VVB) has been used in liver transplantation (LT) to minimize hemodynamic instability during caval anastomosis of anhepatic phase. With the introduction of the piggyback (PB) technique, which is a caval-sparing technique, the use of VVB progressively decreased over the world. The aim of this study was to introduce our experience using VVB with the focus on its weaning process.

METHODS

A total of 300 consecutive LT cases from May 1996 to November 2003 were examined. Except for pediatric LT, 242 LT cases were investigated to evaluate the trends in VVB use, surgical technique, the amount of transfusion requirements, and durations of operation and anhepatic phase.

RESULTS

For the early 100 LT cases, VVB was used in 97.5% of recipients, especially in all the recipients of deceased donor LT (DDLT). Then, the frequency of VVB use was decreased, and VVB was not used after the 268th recipient. In DDLT, the PB technique was first introduced in the 58th recipient and became a routine procedure of the DDLT since the 191th recipient. Living donor LT was increased, and the amount of transfusion requirement, duration of operation, and duration of anhepatic phase was reduced over time.

CONCLUSIONS

The increasing experience and sophisticated surgical and anesthetic techniques were important factors responsible for the weaning of VVB. The advancement of the PB technique used in living donor LT might be a main factor of its weaning.

Association of Platelet Count and Platelet Transfusion With Serotonin Level During Living Donor Liver Transplantation: Possible Connection to Graft Regeneration

BACKGROUND

We recently showed that platelet counts and the amount of platelet transfusion during liver transplantation are positively associated with early graft regeneration. It was hypothesized that platelet-derived serotonin mediates liver regeneration.

OBJECTIVES

This study aimed to evaluate the association between intraoperative platelet count, platelet transfusion, and serum serotonin level.

METHODS

Thirty-two recipients undergoing living-donor liver transplantation were enrolled into this prospective observational study. Serum platelet counts and serotonin levels were measured at the following times: anesthetic induction, start of the anhepatic phase, before graft reperfusion, 5 minutes/1 hour/3 hours/5 hours after graft reperfusion, and before/after platelet transfusion. Serotonin was measured by using a liquid chromatography tandem mass spectrometry.

RESULTS

Serotonin level at the anesthetic induction was 24.5 μg/mL (interquartile range, 14.6 to 38.1 μg/mL). During surgery, serial changes in platelet counts and serotonin levels showed a similar trend: they decreased during the anhepatic phase, increased during the first hour after graft reperfusion, and thereafter gradually decreased. Serotonin level was positively correlated with platelet counts (correlation coefficient = 0.620, P < .001). Allogeneic platelet transfusion significantly increased platelet count from 22 (19-31) × 10⁹/L to 53 (50-81) × 10⁹/L (P = .008) and it also increased serum serotonin from 11.04 (6.41-15.34) μg/mL to 34.26 (25.86-41.94) μg/mL (P = .008).

CONCLUSIONS

Our findings indicate that allogeneic platelets could act as effector cells deriving serotonins. Also, our findings support the hypothesis that the association between platelets and post-transplantation graft regeneration is mediated by serotonin. Further studies are warranted regarding the respective role of serotonin and other platelet-derived molecules mediating liver regeneration.

Ondansetron blocks wild-type and p.F503L variant small-conductance Ca2+-activated K+ channels

Apamin-sensitive small-conductance Ca2+-activated K+ (SK) current ( IKAS) is encoded by Ca2+-activated K+ channel subfamily N ( KCNN) genes. IKAS importantly contributes to cardiac repolarization in conditions associated with reduced repolarization reserve. To test the hypothesis that IKAS inhibition contributes to drug-induced long QT syndrome (diLQTS), we screened for KCNN variants among patients with diLQTS, determined the properties of heterologously expressed wild-type (WT) and variant KCNN channels, and determined if the 5-HT3 receptor antagonist ondansetron blocks IKAS. We searched 2,306,335 records in the Indiana Network for Patient Care and found 11 patients with diLQTS who had DNA available in the Indiana Biobank. DNA sequencing discovered a heterozygous KCNN2 variant (p.F503L) in a 52-yr-old woman presenting with corrected QT interval prolongation at baseline (473 ms) and further corrected QT interval lengthening (601 ms) after oral administration of ondansetron. That patient was also heterozygous for the p.S38G and p.P2835S variants of the QT-controlling genes KCNE1 and ankyrin 2, respectively. Patch-clamp experiments revealed that the p.F503L KCNN2 variant heterologously expressed in human embryonic kidney (HEK)-293 cells augmented Ca2+ sensitivity, increasing IKAS density. The fraction of total F503L-KCNN2 protein retained in the membrane was higher than that of WT KCNN2 protein. Ondansetron at nanomolar concentrations inhibited WT and p.F503L SK2 channels expressed in HEK-293 cells as well as native SK channels in ventricular cardiomyocytes. Ondansetron-induced IKAS inhibition was also demonstrated in Langendorff-perfused murine hearts. In conclusion, the heterozygous p.F503L KCNN2 variant increases Ca2+ sensitivity and IKAS density in transfected HEK-293 cells. Ondansetron at therapeutic (i.e., nanomolar) concentrations is a potent IKAS blocker. NEW & NOTEWORTHY We showed that ondansetron, a 5-HT3 receptor antagonist, blocks small-conductance Ca2+-activated K+ (SK) current. Ondansetron may be useful in controlling arrhythmias in which increased SK current is a likely contributor. However, its SK-blocking effects may also facilitate the development of drug-induced long QT syndrome.

Ischemic Preconditioning Produces Comparable Protection Against Hepatic Ischemia/Reperfusion Injury Under Isoflurane and Sevoflurane Anesthesia in Rats

BACKGROUND

Various volatile anesthetics and ischemic preconditioning (IP) have been demonstrated to exert protective effect against ischemia/reperfusion (I/R) injury in liver. We aimed to determine whether application of IP under isoflurane and sevoflurane anesthesia would confer protection against hepatic I/R injury in rats.

METHODS

Thirty-eight rats weighing 270 to 300 grams were randomly divided into 2 groups: isoflurane (1.5%) and sevoflurane (2.5%) anesthesia groups. Each group was subdivided into sham (n = 3), non-IP (n = 8; 45 minutes of hepatic ischemia), and IP (n = 8, IP consisting of 10-minute ischemia plus 15-minute reperfusion before prolonged ischemia) groups. The degree of hepatic injury and expressions of B-cell lymphoma 2 (Bcl-2) and caspase 3 were compared at 2 hours after reperfusion.

RESULTS

Hepatic ischemia induced significant degree of I/R injuries in both isoflurane and sevoflurane non-IP groups. In both anesthetic groups, introduction of IP dramatically attenuated I/R injuries as marked by significantly lower aspartate aminotransferase and aminotransferase levels and better histologic grades compared with corresponding non-IP groups. There were 2.3- and 1.7-fold increases in Bcl-2 mRNA levels in isoflurane and sevoflurane IP groups, respectively, compared with corresponding non-IP groups (both P < .05). Caspase 3 level was significantly high in the isoflurane non-IP group compared with the sham group; however, there were no differences among the sevoflurane groups.

CONCLUSIONS

The degree of hepatic I/R injury was significantly high in both isoflurane and sevoflurane groups in rats. However, application of IP significantly protected against I/R injury in both volatile anesthetic groups to similar degrees, and upregulation of Bcl-2 might be an important mechanism.

Effect of topical loteprednol etabonate with lid hygiene on tear cytokines and meibomian gland dysfunction in prosthetic eye wearers

PurposeTo assess tear cytokine levels and clinical outcomes in meibomian gland dysfunction (MGD) in the blind eye of patients wearing an ocular prosthesis after 2 months of treatment with topical loteprednol etabonate and eyelid scrubs with warm compresses.Patients and methodsThis study included patients with MGD wearing a unilateral ocular prosthesis for more than 1 year. All patients topically received 0.5% loteprednol etabonate and were instructed to scrub their eyelids with warm compresses on the prosthetic eye for 2 months. We evaluated tear cytokine levels using Multiplex Bead Immunoassays, performed biomicroscopic examination of the lid margins and meibomian gland, conducted meibography imaging, and assessed MGD-related ocular symptoms using a questionnaire for the prosthetic eye before and 2 months after treatment.ResultsThirty consecutive patients were included. There were significant reductions in the levels of interleukin (IL)-6, interferon-γ, monocyte chemotactic protein-1, IL-8, tumor necrosis factor-α, and IL-1β (P<0.001 for each cytokine). Moreover, there were improvements in ocular symptoms (P=0.001), lid margin abnormalities (P<0.001), meibomian gland expressibility (P<0.001) and meibography findings (P=0.037).ConclusionTopical loteprednol etabonate in conjunction with eyelid scrubs and warm compresses were effective in treating MGD in prosthetic eye wearers. Furthermore, tear cytokine measurements may serve as an additional approach for evaluating the efficacy of anti-inflammatory treatment for MGD in prosthetic eye wearers.

Arrhythmogenic calmodulin mutations impede activation of small-conductance calcium-activated potassium current

BACKGROUND

Apamin-sensitive small-conductance calcium-activated potassium (SK) channels are gated by intracellular Ca(2+) through a constitutive interaction with calmodulin.

OBJECTIVE

We hypothesize that arrhythmogenic human calmodulin mutations impede activation of SK channels.

METHODS

We studied 5 previously published calmodulin mutations (N54I, N98S, D96V, D130G, and F90L). Plasmids encoding either wild-type or mutant calmodulin were transiently transfected into human embryonic kidney 293 cells that stably express subtype 2 of SK protein channels (SK2 cells). Whole-cell voltage-clamp recording was used to determine apamin-sensitive current densities. We also performed optical mapping studies in normal murine hearts to determine the effects of apamin in hearts with (n=7) or without (n=3) pretreatment with sea anemone toxin.

RESULTS

SK2 cells transfected with wild-type calmodulin exhibited an apamin-sensitive current density of 33.6 pA/pF (31.4-36.5 pA/pF) (median and confidence interval 25th-75th percentile), which was significantly higher than that observed for cells transfected with N54I (17.0 pA/pF [14.0-27.7 pA/pF]; P = .016), F90L (22.6 pA/pF [20.3-24.3 pA/pF]; P = .011), D96V (13.0 pA/pF [10.9-15.8 pA/pF]; P = .003), N98S (13.7 pA/pF [8.8-20.4 pA/pF]; P = .005), and D130G (17.6 pA/pF [13.8-24.6 pA/pF]; P = .003). The decrease in SK2 current densities was not associated with a decrease in membrane protein expression or intracellular distribution of the channel protein. Apamin increased the ventricular action potential duration at 80% repolarization (from 79.6 ms [63.4-93.3 ms] to 121.8 ms [97.9-127.2 ms]; P = .010) in hearts pretreated with anemone toxin but not in control hearts.

CONCLUSION

Human arrhythmogenic calmodulin mutations impede the activation of SK2 channels in human embryonic kidney 293 cells.

Evaluation of "flat-line" thromboelastography after reperfusion during liver transplantation

BACKGROUND

"Flat-line" (no clot formation) thromboelastography (TEG) is frequently observed after graft reperfusion during liver transplantation (LT). We aimed to evaluate the incidence and causes of flat-line TEG after graft reperfusion during LT.

METHODS

With institutional review board approval, data of 208 consecutive recipients who underwent LT from May 2010 to May 2012 were retrospectively reviewed. We performed 3 different types of TEG measurements at 5 minutes after graft reperfusion: native TEG (nTEG), tranexamic acid-added TEG (tTEG), and protamine-added TEG (pTEG). The flat-line TEG was defined as having no trace at all at 60 minutes of TEG. We examined the incidence and causes of flat-line nTEG. We also compared recipients with flat-line nTEG (F group) and clot-forming nTEG (C group).

RESULTS

One hundred eighty-two recipients were included in the final analysis. The incidence of flat-line nTEG was 27% (49/182 cases). Among 49 recipients in the F group, 28 recipients showed clot formation in both tTEG and pTEG, 19 recipients in only tTEG, and 1 recipient in only pTEG; 1 recipient showed no clot formation in any TEGs. Graft from the deceased donor was more frequently observed in the F group than in the C group (P = .039). The F group showed decreased platelet count (P = .001), increased prothrombin time (P = .002), and decreased fibrinogen (P = .009) compared with the C group.

CONCLUSIONS

No clot formation was relatively common after reperfusion during LT, and the main causes were hyperfibrinolysis and heparin effect. Liver graft from deceased donors was associated more frequently with no clot formation after reperfusion during LT.

Small-Conductance Calcium-Activated Potassium Current Is Activated During Hypokalemia and Masks Short-Term Cardiac Memory Induced by Ventricular Pacing

BACKGROUND

Hypokalemia increases the vulnerability to ventricular fibrillation. We hypothesize that the apamin-sensitive small-conductance calcium-activated potassium current (IKAS) is activated during hypokalemia and that IKAS blockade is proarrhythmic.

METHODS AND RESULTS

Optical mapping was performed in 23 Langendorff-perfused rabbit ventricles with atrioventricular block and either right or left ventricular pacing during normokalemia or hypokalemia. Apamin prolonged the action potential duration (APD) measured to 80% repolarization (APD80) by 26 milliseconds (95% confidence interval [CI], 14-37) during normokalemia and by 54 milliseconds (95% CI, 40-68) during hypokalemia (P=0.01) at a 1000-millisecond pacing cycle length. In hypokalemic ventricles, apamin increased the maximal slope of APD restitution, the pacing cycle length threshold of APD alternans, the pacing cycle length for wave-break induction, and the area of spatially discordant APD alternans. Apamin significantly facilitated the induction of sustained ventricular fibrillation (from 3 of 9 hearts to 9 of 9 hearts; P=0.009). Short-term cardiac memory was assessed by the slope of APD80 versus activation time. The slope increased from 0.01 (95% CI, -0.09 to 0.12) at baseline to 0.34 (95% CI, 0.23-0.44) after apamin (P<0.001) during right ventricular pacing and from 0.07 (95% CI, -0.05 to 0.20) to 0.54 (95% CI, 0.06-1.03) after apamin infusion (P=0.045) during left ventricular pacing. Patch-clamp studies confirmed increased IKAS in isolated rabbit ventricular myocytes during hypokalemia (P=0.038).

CONCLUSIONS

Hypokalemia activates IKAS to shorten APD and maintain repolarization reserve at late activation sites during ventricular pacing. IKAS blockade prominently lengthens the APD at late activation sites and facilitates ventricular fibrillation induction.

Risk factors for inadvertent hypothermia during adult living-donor liver transplantation

BACKGROUND

Hypothermia (core temperature <35°C) causes multiple physiologic disturbances, including coagulopathy and cardiac dysfunction. Patients undergoing liver transplantation are at risk of inadvertent hypothermia and might be more vulnerable to its adverse effects. We sought to identify the factors contributing to hypothermia during living-donor liver transplantation (LDLT), which have not yet been studied in depth.

METHODS

Medical records of 134 recipients who underwent adult-to-adult LDLT were reviewed. Core temperature at the following time points were taken: anesthetic induction, skin incision, start and end of the anhepatic phase, and hourly after hepatic reperfusion.

RESULTS

Of 134 recipients, 29 (21.6%) developed hypothermia during surgery. Four independent risk factors for hypothermia were identified: small body weight-to-body surface area ratio, acute hepatic failure, high Model for End-Stage Liver Disease (MELD) score, and low graft-to-recipient weight ratio. The amount of core temperature drop was positively correlated with the number of involved risk factors. Each risk factor had a respective contribution according to the operative phases: body weight-to-body surface area ratio and the MELD score for the preanhepatic phase, acute deterioration of hepatic failure for the anhepatic phase, and graft-to-recipient weight ratio was for the postreperfusion phase.

CONCLUSIONS

Hypothermia was independently associated with the recipient's morphometric characteristics, emergency of end-stage liver disease, MELD score, and graft volume. These factors showed a cumulative effect, and the role of each factor was different according to the operative phase. These results should aid in the development of an optimal thermal strategy during LDLT.

Analysis of predictors for lactate elimination after reperfusion in recipients of living-donor liver transplantation

BACKGROUND

Graft-recipient weight ratio (GRWR) is the only documented predictor that influences the lactate elimination after reperfusion in living-donor liver transplantation (LDLT). This study was performed to investigate the predictors of lactate elimination after reperfusion in recipients of adult LDLT.

METHODS

The medical records of 159 patients who underwent LDLT were analyzed. Lactate level (mmol/L) was measured from just before the initiation of surgery (P0) and 5, 60, and 120 minutes after reperfusion of graft (R0, R1, and R2, respectively). The change of lactate level after reperfusion was defined as difference between lactate level measured at R0 and R2. Patients were divided into accumulation and elimination groups. Donor and recipient factors were compared between the 2 groups.

RESULTS

Lactate accumulation occurred in 80 of 159 recipients (50.3%), and elimination occurred in 79 (49.7%). GRWR and Model for End-Stage Liver Disease (MELD) score were higher in the elimination group. Lactate at R0 was lower in the elimination group.

CONCLUSIONS

Higher GRWR and MELD score and lower lactate level immediate after reperfusion of graft were predictors of lactate elimination after reperfusion during adult LDLT.

Factors associated with consciousness recovery time after liver transplantation in recipients with hepatic encephalopathy

BACKGROUND

Hepatic encephalopathy (HE) occurs as a result of liver failure and is often considered to be a clinical indication for liver transplantation (LT). An assessment of post-transplantation consciousness level in recipients with HE is crucial, because recovery of consciousness implies reestablishment of transplant liver function and lack of perioperative brain damage. The purpose of this study is to evaluate factors associated with consciousness recovery time after LT in recipients with HE.

METHODS

Out of 633 adult recipients who underwent LT, recipients who exhibited HE at the time of LT were analyzed retrospectively. The time between graft reperfusion and postoperative consciousness recovery was determined, and recipients were divided into 2 groups: group E with recovery of consciousness early (≤48 hours), and group L with recovery of consciousness late (>48 hours). Analyzed variables included recipient sex, age, graft type, Model for End-Stage Liver Disease score, HE history/duration/type/grade, and preoperative laboratory values, including blood ammonia concentration.

RESULTS

HE was present at the time of LT in 69 (10.9%) of 633 recipients. Among the 69 recipients, 11 recipients who died or underwent reoperation before consciousness recovery were excluded, and 58 recipients (group E: n = 32; group L: n = 26) were enrolled into analysis. Multivariate analysis showed that HE duration >5 days (odds ratio [OR], 15.58; 95% confidence interval [CI], 1.35-179.56; P = .028) and HE type C (OR, 30.90; 95% CI, 1.67-573.48; P = .021) were the independent factors associated with late recovery from HE after LT.

CONCLUSIONS

We suggest that recipients with long-duration or type C HE should be carefully managed during the post-transplantation period to prevent deterioration of HE.

Acute postoperative pain relief with immediate-release tapentadol: randomized, double-blind, placebo-controlled study conducted in South Korea

OBJECTIVE

To broaden the ethnic groups in which tapentadol IR is evaluated for treating acute postoperative pain to include Asians.

METHODS

In this phase 3, multicenter, double-blind, randomized study, 352 Korean adults with moderate-to-severe pain following hallux valgus surgery received tapentadol IR 50 or 75 mg or placebo orally every 4-6 hours for 72 hours. Patients requesting other (rescue) analgesics during this period were discontinued for lack of efficacy. The primary endpoint, sum of pain intensity difference (SPID) over 48 hours, was evaluated based on the difference between tapentadol IR and placebo in least squares (LS) mean change from baseline using analysis of covariance (ANCOVA). Secondary endpoints included the time to first rescue medication use and the distribution of responder rates.

RESULTS

A treatment effect, favoring tapentadol IR, was observed for SPID48 (p < 0.001 for both doses vs. placebo, ANCOVA). The between-group difference (vs. placebo) in LS means of SPID48 was 76.4 (95% CI: 51.0, 101.7) for tapentadol IR 50 mg and 90.6 (95% CI: 65.1, 116.1) for tapentadol IR 75 mg. Time to first rescue medication use was delayed for tapentadol IR (p < 0.001 for both doses vs. placebo; log-rank test). The distribution of responders at 12, 24, 48, and 72 hours favored tapentadol IR (p ≤ 0.001 for both doses vs. placebo; Cochran-Mantel-Haenszel test). Dizziness, nausea, and vomiting were each reported in ≥ 10% tapentadol-treated patients and at an incidence ≥ 2-fold higher vs. placebo. The study findings may be limited by study drug dosing every 4 to 6 hours and frequent monitoring during treatment, neither of which mimic pain treatment in clinical practice. However, any potential bias based on this systematic monitoring of patients would be mitigated by the randomized, double-blind nature of the study, with all treatment groups similarly affected by such biases, if any.

CONCLUSIONS

Tapentadol IR reduced acute pain intensity, significantly more than placebo, after orthopedic surgery in Korean patients.

CLINICAL TRIAL REGISTRATION

NCT01516008.

Identification of novel mutations in the VPS33B gene involved in arthrogryposis, renal dysfunction, and cholestasis syndrome

Arthrogryposis, renal dysfunction, and cholestasis (ARC) syndrome is an autosomal recessive disorder caused by mutations in the VPS33B and VIPAS39. Here, we report novel mutations identified in four patients with ARC syndrome. We analyzed the entire coding regions of the VPS33B and VIPAS39 genes by direct sequencing. To detect novel splice site mutations, mRNA transcripts were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and sequencing. All four patients had compound heterozygous variants in the VPS33B gene. One patient had a previously reported splice site variant with unknown significance, c.239+5G>A, and a novel nonsense mutation, c.621G>A. The other three patients had the c.403+2T>A mutation, and each of them carried one of the splice site variants, c.239+5G>A or c.499-11G>A. c.239+5G>A and c.499-11G>A created novel splice sites which resulted in abnormal transcripts. No significant VIPAS39 mutation was detected in all patients. In patients suspected with ARC syndrome, mutation analysis of the VPS33B gene should be employed as a primary diagnostic test before performing invasive testing procedures such as organ biopsies. Performing mRNA analysis can be useful in predicting the pathogenic phenotype when the mutation seems to affect a normal splicing mechanism.

The comparisons of hepatitis C virus RNA level between intraoperative blood salvage (cell saver) and systemic hepatitis C virus RNA kinetics during liver transplantation

BACKGROUND

Cell Saver (CS; Haemonemic Corp, Braintree, Mass, United States) is frequently used to decrease transfusion requirements of homologous blood during liver transplantation (OLT). However, the use of CS in hepatitis C virus (HCV)-infected recipients is still debated owing to the potential elevation of HCV RNA level. In this study, we compared HCV RNA levels of CS blood with a series of blood samples obtained from HCV-infected OLT recipients.

METHODS

Twelve HCV-infected patients with >50,000 copies/mL of HCV RNA were enrolled. HCV RNA was measured immediately after induction (I), at the end of anhepatic period (II), at the end of operation (III), and from the first returned blood in CS (CSb). HCV RNA level at each time period was compared.

RESULTS

HCV RNA levels ranged from 77,931 to 9,072,000 copies/mL at I. When compared to I, HCV RNA levels were reduced to 11.1% ± 13.0% and 0.7% ± 1.0% at II and III, respectively. Also, the RNA level reduced to 3.0% ± 2.0% of I after CS processing. The HCV RNA level at I was significantly higher than the levels at II, III, and CSb (P = .012, each), and the level at II was significantly higher than the level at III (P = .012). The HCV RNA level at CSb showed no statistical difference with the levels at II, but it was significantly higher than the level at III (P = .042).

CONCLUSIONS

The use of CS in HCV-infected OLT recipients seems to carry no additional risk with respect to intraoperative HCV RNA kinetics.

The comparison of femoral and radial arterial blood pressures during pediatric liver transplantation

BACKGROUND

Orthotopic liver transplantation (OLT) is frequently associated with dramatic hemodynamic changes; thus, it is critical to accurately monitor blood pressure. Although comparisons between femoral arterial blood pressure (FABP) and radial arterial blood pressure (RABP) have been reported in adult liver recipients, we compared FABP with RABP in pediatric recipients.

METHODS

Thirty-five pediatric liver recipients younger than 13 years of age were included in this prospective, observational study. We measured simultaneous FABP and RABP in the femoral and radial arteries at nine time points during the procedure, including: baseline (after anesthetic induction); 1 hour thereafter; 30 minutes after the beginning of the anhepatic period as well as 0, 1, 3, 5, 15, and 60 minutes after graft reperfusion.

RESULTS

Of the 35 pediatric liver recipients, 2 infants and 1 13-month-old child were excluded from the analysis because of radial arterial catheter malfunction. The remaining 32 patients including 16 infants and 16 children all showed significantly higher systolic and mean FABP than RABP during most stages of pediatric OLT. Overall diastolic FABP measurements were similar to diastolic RABP throughout the study.

CONCLUSIONS

Systolic and mean FABP were significantly higher than RABP during most stages of pediatric OLT. Radial arterial catheter malfunctions were not uncommon during pediatric OLT. Our results indicated that it is useful to cannulate the femoral artery to accurately and reliably measure arterial blood pressure to detect hemodynamic instability during pediatric OLT.

Comparison of mixed venous oxygen saturation after in vitro calibration of pulmonary artery catheter with that of pulmonary arterial blood in patients undergoing living donor liver transplantation

INTRODUCTION

Mixed venous saturation (SvO2) reflects the balance between oxygen delivery and consumption throughout the body. A multifunction pulmonary artery catheter (PAC) can monitor continuous SvO2 after in vitro calibration (CSvO2), obviating the need for in vivo calibration with pulmonary arterial blood. In critically ill patients CSvO2 has shown a good correlation with measured SvO2 of pulmonary arterial blood using co-oximetry (MSvO2). The aim of this study was to compare CSvO2 and MSvO2 in liver transplantation (OLT) recipients.

METHODS

We enrolled 44 OLT recipients for comparison with 24 coronary artery bypass graft (CABG) controls free of end-stage liver disease. After anesthetic induction, the PAC was inserted after in vitro calibration and CSvO2 and MSvO2 simultaneously measured. In OLT recipients, additional measurements of CSvO2 and MSvO2 were performed at anhepatic and postreperfusion phases. Pearson's correlation analysis was used to evaluate the correlation between the 2 measurements. A Bland-Altman analysis was used to determine precision of and bias between the 2 measurements. With ±3% regarded to be interchangeable.

RESULTS

Cardiac output and intrapulmonary shunt in CABG patients were lower than among OLT recipients. OLT recipients, showed a significant correlation between CSvO2 and MSvO2, but the coefficients were different during the three phases of OLT (r = 0.597, 0.753, and 0.756). In addition, bias values between the two measurements were 6.0%, 6.4%, and 2.9% for the preanhepatic, anhepatic, and postreperfusion phases, respectively, with 29.5%, 31.8%, and 50% of them being interchangeable. In contrast CABG patients showed bias in -0.17% with 75% of measurements interchangeable.

CONCLUSION

While in vitro calibration of the PAC can be used in CABG patients, MSvO2 is higher than CSvO2 in OLT recipients. Therefore, in vivo calibration with pulmonary arterial blood is necessary for accurate monitoring of SvO2 in OLT recipients.

Vecuronium requirements according to the operative phase during living donor liver transplantation under desflurane anesthesia

INTRODUCTION

The requirements of nondepolarizing neuromuscular blocking agent during liver transplantation show conflicting results. We sought to evaluate the requirements according to the operative phase and find extrahepatic factors that influence neuromuscular blocking agent requirements.

METHODS

We enrolled 35 patients undergoing living donor liver transplantation. Continuous infusion of vecuronium was adjusted every 15 minutes for consistent neuromuscular blockade aimed at T1/Tc of 0.10 monitored with a neuromuscular transmission module. We compared the mean infusion dose in each phase, and investigated whether it is correlated with preoperative Model for End-Stage Liver Disease (MELD) score, Child-Turcotte-Pugh (CTP) score, graft-recipient weight ratio (GRWR), or time to recovery of first twitch response to train-of-four (TOF) stimulation.

RESULTS

There was a significant difference between vecuronium doses during each phase (P < .001): 0.48 ± 0.16 μg/kg/min, preanhepatic; 0.38 ± 0.14 μg/kg/min, anhepatic and 0.26 ± 0.07 μg/kg/min, neohepatic phase. There was a significant positive correlation between vecuronium infusion dose in the preanhepatic phase and CTP scores (P = .006, correlation coefficient = 0.465). There was also a significant negative correlation between the time to recovery of first twitch response of TOF stimulation and vecuronium infusion dose in the preanhepatic phase (P = .001, correlation coefficient = -0.546). The infusion dose during the preanhepatic phase was not associated with the MELD score, and that of neohapatic phase not with GRWR.

CONCLUSIONS

The vecuronium infusion dose requirement during the anhepatic decreased compared with that in the preanhepatic phase. It further decreased during the neohepatic phase compared with the previous phases. Vecuronium infusion dose reduction is suggested especially during the neohepatic phase for early extubation. The dose during the preanhepatic phase is suggested to be determined considering the CTP score and the time to recovery of the TOF response.

Rotational resonance of nonaxisymmetric magnetic braking in the KSTAR tokamak

One of the important rotational resonances in nonaxisymmetric neoclassical transport has been experimentally validated in the KSTAR tokamak by applying highly nonresonant n=1 magnetic perturbations to rapidly rotating plasmas. These so-called bounce-harmonic resonances are expected to occur in the presence of magnetic braking perturbations when the toroidal rotation is fast enough to resonate with periodic parallel motions of trapped particles. The predicted and observed resonant peak along with the toroidal rotation implies that the toroidal rotation in tokamaks can be controlled naturally in favorable conditions to stability, using nonaxisymmetric magnetic perturbations.

Arthroscopic shoulder surgery under general anesthesia with brachial plexus block: postoperative respiratory dysfunction of combined obstructive and restrictive pathology

OBJECTIVE

Changes in respiratory parameters and pulmonary function tests were evaluated after shoulder arthroscopic surgery with brachial plexus block (BPB). The purpose of this study was to identify the mechanism of respiratory dysfunction after this type of surgery.

METHODS

Patients undergoing arthroscopic rotator cuff repair under general anesthesia (GA) with BPB were enrolled in the arthroscopy group (n = 30) while those undergoing open reduction of a clavicle or humerus fracture under GA were enrolled in the control group (n = 30). Forced vital capacity (FVC) and forced expiratory volume 1 s (FEV(1)) were measured at the outpatient clinic stage (#1) before (#2) and 20 min after BPB (#3) and 1 h after extubation (#4). Respiratory variable measurements along with the cuff leak test were performed 5 min after surgical positioning (T1) and at the start of skin closure (T2). Respiratory discomfort was evaluated after extubation. The upper airway diameters and soft tissue depth of chest wall were also measured by ultrasonography at stages #3 and #4.

RESULTS

Static compliance decreased significantly at T2 in the arthroscopy group (50 ± 11 at T1 vs. 44 ± 9 ml/cm H(2)O at T2, p =0.035) but not in the control group. The incidence of positive cuff leak tests at T2 was significantly higher in the arthroscopy group than in the control group (47% in the arthroscopy group vs. 17% in controls, p =0.010). While FEV(1) and FVC remained stable at stages #1 and #2, FVC and FEV(1) decreased at stages #3 and #4 only in the arthroscopy group (FVC in arthroscopy group, #2: 3.26 ± 0.77 l; #3: 2.55 ± 0.63 l, p =0.015 vs. #2; #4: 2.66 ± 0.41 l, p =0.040 vs. #2). The subglottic diameter decreased at #4 in the arthroscopy group, while no changes occurred in the control group (0.70 ± 0.21 cm vs. 0.85 ± 0.23 cm in the arthroscopy and control groups, respectively, p =0.011). Depth of skin to pleura increased at both intercostal spaces 1-2 and 3-4 in the arthroscopy group. There were three cases of hypoxia (S(p)O(2) < 95%) with room air in the arthroscopy group while none occurred in the controls.

CONCLUSION

Shoulder arthroscopic surgery under GA with BPB induced both restrictive and obstructive pathologies. It is important to maintain a high level of awareness for the potential negative respiratory effects of this surgery especially for subjects with pre-existing cardiopulmonary disease. The measurements in this study would be useful to monitor the risk of respiratory dysfunction in these patients.

The relationship between postoperative intravenous patient-controlled fentanyl analgesic requirements and severity of liver disease

PURPOSE

Decreased inhalational anesthetic requirements during orthotopic liver transplantation (OLT) have been reported according to the severity of the pre-existent disease as well as decreased opioid requirements thereafter. The aim of the present study was to determine the relationship between postoperative opioid requirements and severity of liver disease among OLT patients.

METHODS

We retrospectively reviewed 44 recipients who used intravenous fentanyl-based patient-controlled analgesia (PCA) after OLT from November 2009 to May 2010. The severity of liver disease was assessed using the model for end-stage liver disease (MELD) score. Recipients were divided into a low-MELD group (<20; n=30) and a high-MELD group (≥20; n=14). The amounts of PCA infusion and rescue opioid up to 3 postoperative days (POD) were compared between the 2 groups. The intensity of pain at rest and when coughing was assessed using visual analog scale (VAS) scores.

RESULTS

The cumulative opioid requirements via PCA on POD 1, 2, and 3 were significantly lower in the high-MELD than the low-MELD group. The amounts of rescue opioid were similar between the 2 groups. However, the intensity of pain at both rest and when coughing on POD 1, 2, and 3 were significantly less severe in the high-MELD than the low-MELD group.

CONCLUSIONS

OLT patients with high MELD scores required less postoperative opioids and experienced less pain than those with low scores. Therefore, postoperative pain control after OLT should be carefully titrated according to the severity of the liver disease.

Which score system can best predict recipient outcomes after living donor liver transplantation?

INTRODUCTION

Many scoring systems have been suggested to predict the outcomes of deceased donor liver transplantations. The aims of this study were to compare the Model for End-Stage Liver Disease (MELD) score with respect to other scores among patients who underwent living donor liver transplantation (LDLT) seeking to evaluate the best system to correlate with postoperative outcomes after LDLT.

METHODS

We analyzed retrospectively data from 202 adult patients who underwent LDLT from January 2008 to July 2010. We calculated preoperative MELD, MELD-sodium, MELD to serum sodium ratio (MESO), integrated MELD, United Kingdom MELD, Child-Turcotte-Pugh, Acute Physiology and Chronic Health evaluation II (APACHE II), and Sequential Organ Failure Assessment (SOFA) scores in all patients. We analyzed the correlation of each score with postoperative laboratory results, as well as survival at 1, 3, 6 and 12 months after LDLT.

RESULTS

There was significant positive correlation between all scores and peak total bilirubin during the first 7 days after LDLT. The MELD score showed the greatest correlation with peak total bilirubin (r=0.745). APACHE II and SOFA scores at 6 months and 1 year after LDLT and MESO score at 1 year after LDLT showed acceptable discrimination performance {area under the receiver operating characteristic curves (AUC)>0.7, while other scoring systems showed poor discrimination. However, the AUCs of each score were not significantly different from the MELD score AUC.

CONCLUSION

The MELD score most correlated with total bilirubin after LDLT, while the APACHE II and SOFA scores seemed to correlate with mortality after LDLT.

Predictors of high intraoperative blood loss derived by simple and objective method in adult living donor liver transplantation

We conducted a risk factor analysis for high intraoperative blood loss (IBL) in 555 living donor liver transplantation (LDLT) cases with a simple and objective method of IBL estimation based on the concept of red cell mass (RCM): Lost RCM (mL) = patient's estimated blood volume (mL) × (preoperative hematocrit in % - postoperative hematocrit in %) + (transfused leukocyte-depleted red blood cell in units × 213 × 70%) + (transfused Cell Saver blood in mL × 55%). Analysis of 33 preoperative variables revealed that Model for End-stage Liver Disease (MELD) score, albumin, the presence of ascites, and previous abdominal surgery were correlated with high IBL (lost RCM > 1000 mL) in multivariate logistical regression analysis. In conclusion, we found that MELD score, albumin, the presence of ascites, and previous abdominal surgery were significantly correlated with high IBL during adult LDLT.

Abstract P2-02-05: Combined Ultrasound/MRI for Breast Cancer Screening in Asian Women of Average Cancer Risk

Background and purpose: MRI is not recommended for screening women at average risk because it is associated with substantial numbers of false-positive results and cost. MRI as a screening tool for breast cancer, however, involves a complexity of cancer epidemiology, socio-economic situation, healthcare policy, and awareness and compliance of general population. Breast MRI may be particularly beneficial as a screening tool for Asian women due to their dense breast. In this study we reported the breast MRI screening results in Chinese women in Taiwan. Materials and Methods: In a period of 8 years, 3681 women underwent breast MRI examination in our imaging center. Of them, 95 women were known to have prior histories of cancers and were excluded from this study. The remaining breast MR images from 3,586 asymptomatic healthy women (mean age, 45.3 years) were retrospectively analyzed in this study. All subjects came to our imaging center for screening breast MR studies by self-referral due to high concern of cancer. All subjects were examined at a 1.5T scanner. The imaging interpretation was based on the criteria of ACR BI-RADS lexicon. After the breast MRI examination, complementary US was performed. If suspicious lesions were detected on MRI but showed negative results on US, double check with targeted US were done by the same radiologist immediately. US was also used to guide needle biopsy when in need.

Results: Overall, among 3,586 cases, totally 115 subjects were suspected to have malignant lesions and ultrasound-guided biopsy (N=106) and/or aspiration cytology study (N=122) was performed in all these 115 subjects. 47 were proved to have malignant lesions in pathology (35 invasive cancers — 27 IDC, 7 ILC, and one apocrine carcinoma; and 12 cases of carcinoma in situ). 31 additional cases of pre-cancerous lesions were found. The mean age in cancer group was 49 y/o and 52.2 y/o in CIS group. Subjects at age 41-50 group had the highest incidence of cancer detection, including 6 in situ lesions and 19 invasive cancers. Five cases were found to have breast cancers 1 or 2 years later. The incidence for malignancy in our asymptomatic group was about 1.31% (47/3586) and increased to 2.2% (78/3586) if precancerous lesions were included. The overall sensitivity of combined US/MRI was 94% and specificity was 99%. Conclusions: Breast MRI can be an option for Asian women of average risk, who usually have dense breast, at their own cost. From our results, it was shown that combined ultrasound and MRI can achieve high sensitivity and specificity for women of average risk. The unnecessary biopsy due to the false positive diagnosis of breast MRI can also be reduced remarkably.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P2-02-05.

The safety of simultaneous bilateral versus unilateral total knee arthroplasty: the experience in a Korean hospital

INTRODUCTION

The safety of simultaneous bilateral total knee arthroplasty (SBTKA) remains controversial. This study aimed to compare the postoperative outcomes of SBTKA versus unilateral total knee arthroplasty (UTKA) performed by a single surgeon at a tertiary teaching hospital in Korea.

METHODS

629 female patients with total knee arthroplasty (308 patients for SBTKA and 321 for UTKA) performed under combined spinal epidural anaesthesia (CSE) were selected, and their medical records during admission and follow-up visits for a duration of six months after discharge were reviewed.

RESULTS

Although significantly higher incidences of postoperative confusion and hypoxia during hospitalisation and a longer hospital stay were demonstrated in the SBTKA group, the rates of serious postoperative complications, such as myocardial infarction and deep venous thrombosis, were not different between the groups during the hospital stay and six months afterwards. No death associated with the surgery was encountered in both groups.

CONCLUSION

It was concluded that SBTKA under CSE may be considered to be relatively safe in Korean female patients.

Comparison of femoral arterial blood pressure with radial arterial blood pressure and noninvasive upper arm blood pressure in the reperfusion period during liver transplantation

PURPOSE

The reperfusion period during liver transplantation is hemodynamically unstable. Accurate blood pressure measurements are the mainstay for the efficient management of abrupt cardiovascular changes. We sought to compare femoral arterial blood pressure (FABP) with radial arterial blood pressure (RABP) and noninvasive upper arm blood pressure (NIBP) in the reperfusion period.

METHODS

Thirty-six adult living donor liver recipients were enrolled in this prospective study. Blood pressures in 3 locations were simultaneously recorded from 1 minute before reperfusion to 15 minutes after reperfusion. We evaluated agreements between FABP and RABP and between FABP and NIBP using intraclass correlation coefficients. Also, we investigated the rates of postreperfusion syndrome (PRS) based on the measurements from 3 locations.

RESULTS

After reperfusion, the mean and diastolic RABP agreed more with the corresponding FABP than NIBP. However, systolic NIBP showed high agreement with FABP from 3 to 10 minutes after reperfusion in contrast with the moderate agreement between systolic RABP with FABP, and systolic values of NIBP than RABP were closer to FABP. The rates of PRS based on FABP, RABP, and NIBP measurements were 50.0% (18/36), 80.6% (29/36), and 50.0% (18/36), respectively.

CONCLUSIONS

We believe that NIBP in addition to RABP may be considered to be a reliable alternative when FABP is not available to evaluate hemodynamic instability in the reperfusion period during liver transplantation.

Lipid A-associated proteins from Porphyromonas gingivalis stimulate release of nitric oxide by inducing expression of inducible nitric oxide synthase

BACKGROUND AND OBJECTIVE

The purpose of this study was to examine the effects of lipid A-associated proteins from Porphyromonas gingivalis, a major cause of inflammatory periodontal disease, on the production of nitric oxide and expression of inducible nitric oxide synthase in the murine macrophage cell line, RAW264.7. We also attempted to throw light on the signaling mechanisms involved in P. gingivalis lipid A-associated protein-induced nitric oxide production.

MATERIAL AND METHODS

The lipid A-associated proteins from P. gingivalis 381 were prepared by standard hot phenol-water extraction of endotoxin isolated by the butanol method. Nitric oxide production was assayed by measuring the accumulation of nitrite in culture supernatants. Western blot analysis of inducible nitric oxide synthase and analysis of reverse transcription-polymerase chain reaction products were carried out.

RESULTS

We found that P. gingivalis lipid A-associated proteins can induce inducible nitric oxide synthase expression and stimulate the release of nitric oxide without additional stimuli, and we demonstrated that multiple signaling pathways, such as nuclear factor-kappaB, microtubule polymerization, protein tyrosine kinase, protein kinase C, and mitogen-activated protein kinase cascades, are involved in P. gingivalis lipid A-associated protein-stimulated nitric oxide production. The production of nitric oxide required l-arginine.

CONCLUSION

The present study clearly shows that P. gingivalis lipid A-associated proteins fully induced inducible nitric oxide synthase expression and nitric oxide production in RAW264.7 cells in the absence of other stimuli. The ability of P. gingivalis lipid A-associated proteins to promote the production of nitric oxide may be important in the pathogenesis of inflammatory periodontal disease.

Lipopolysaccharide from Prevotella nigrescens stimulates osteoclastogenesis in cocultures of bone marrow mononuclear cells and primary osteoblasts

BACKGROUND AND OBJECTIVE

Lipopolysaccharide is thought to be a major virulence factor of pathogens associated with periodontal diseases and is believed to stimulate bone resorption in vivo. Although Prevotella nigrescens has been implicated in periodontitis, its role in osteoclastogenesis has not been reported. In this study, we investigated the effects of lipopolysaccharide from P. nigrescens on the formation of osteoclasts and the production of cytokines related to osteoclast differentiation.

MATERIAL AND METHODS

Mouse bone marrow mononuclear cells were cultured in the presence of macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor kappaB ligand (RANKL), with or without lipopolysaccharide. Bone marrow mononuclear cells were also cocultured with calvarial osteoblastic cells in the presence or absence of lipopolysaccharide. Osteoclast formation was determined by tartrate-resistant acid phosphatase cytochemistry. The production of osteoprotegerin (OPG), M-CSF, tumor necrosis factor alpha (TNF-alpha), transforming growth factor-beta (TGF-beta) and prostaglandin E2 (PGE2) was determined by enzyme-linked immunosorbent assay (ELISA).

RESULTS

P. nigrescens lipopolysaccharide inhibited osteoclast differentiation from bone marrow mononuclear cells cultured in the presence of M-CSF and RANKL. However, in the coculture system, P. nigrescens lipopolysaccharide stimulated osteoclastogenesis. Notably, P. nigrescens lipopolysaccharide decreased OPG production but increased TGF-beta secretion. In addition, treatment with P. nigrescens lipopolysaccharide increased PGE2 production during the late stage of the culture period. There was no difference in M-CSF and TNF-alpha production.

CONCLUSION

These results demonstrate that P. nigrescens lipopolysaccharide stimulates osteoclastogenesis in the coculture system by decreasing the production of OPG and increasing the production of TGF-beta and PGE2. Through the mechanisms involving these factors, P. nigrescens lipopolysaccharide may cause alveolar bone resorption in periodontal diseases.

The effects of the exaggerated lithotomy position for radical perineal prostatectomy on respiratory mechanics

The exaggerated lithotomy position is used during radical perineal prostatectomy to increase perineal exposure. The aim of this study was to evaluate the effects of the exaggerated lithotomy position on respiratory mechanics and arterial blood gases. In the exaggerated lithotomy position, dynamic compliance and static compliance were found to be significantly decreased by 27.4% and 34.8%, respectively, whilst peak, plateau, and mean airway pressures increased significantly by 34.0%, 45.8% and 31.7%, respectively. The physiological dead space/tidal volume ratio and total inspiratory work of breathing increased significantly by 11.1% and 33.7%, respectively. Arterial oxygen tension was significantly decreased by 26.9%; however, no significant differences were seen in end-tidal or arterial carbon dioxide tension. These results indicate that the exaggerated lithotomy position under general anaesthesia can cause significant effects on respiratory system mechanics and arterial oxygenation and highlights the need for careful monitoring of patients placed in this position for surgery.

Different patterns of lymphoscintigraphic findings in patients with intestinal lymphangiectasia

Technetium-99m antimony sulfide colloid lymphoscintigraphy conveniently demonstrates intestinal leakage of lymph in patients with intestinal lymphangiectasia. However, we found no intestinal radioactivity in some patients. We evaluated lymphoscintigraphic findings and compared them with clinical data. Technetium-99m antimony colloid lymphoscintigraphy was performed in 12 patients (age, 8.9+/-6.4 years; male:female=8:4) with histologically proven intestinal lymphangiectasia. After subcutaneous injection of 103.6 MBq of technetium-99m antimony colloid into the webs of both feet, sequential abdominal images were obtained up to 24 h post-injection. Four patients underwent technetium-99m methylene diphosphonate bone scintigraphy. Patients were divided into two groups according to the presence or absence of intestinal radioactivity. Five showed intestinal activity (Group 1), but seven did not (Group 2). No Group 1 patient had a history of ascites, while all Group 2 patients had ascites as the initial manifestation. Serum total protein and albumin levels were significantly lower in Group 1 patients than in Group 2 patients. In three Group 1 patients, technetium-99m methylene diphosphonate bone scintigraphy revealed intestinal radioactivity, while in one Group 2 patient this was not found. We observed two types of lymphoscintigraphic pattern in patients with intestinal lymphangiectasia. To clarify the exact pathophysiology, further study is required.

Endovascular aortic graft exclusion of abdominal aortic aneurysm

Endovascular repair of abdominal aortic aneurysms has evolved dramatically within the past few years. This study reports the first successful case in Taiwan area of infrarenal abdominal aortic aneurysm treated with endovascular aortic bifurcational stent-graft. Minimally invasive surgery leading to early recovery, mobilization and shortened hospital day was promising. In addition, there were no local, remote or systemic complications during a 18-month follow-up. Thus, the procedure is an attractive alternative in its potential to reduce morbidity and mortality associated with open surgical repair, especially for patients who are not surgical candidates because of comorbidities. Careful patient selection and more experiences with refined endograft models will elucidate the feasible alternative to conventional surgical repair.

Dissolution of poorly crystalline apatite crystals by osteoclasts determined on artificial thin-film apatite

Poorly crystalline apatite (PCA) crystals introduced into bone tissue should be stable for a definite period before they are dissolved as a result of a host response. In this report, the dissolution of PCA crystals by the action of osteoclasts was studied on artificial thin films. These consisted of PCA crystals having similar crystallographic properties to bone crystals which were developed for assaying the osteoclast activity in vitro. The dissolution of minerals by osteoclasts decreased along with the decreased amount of labile phosphate and hydrogen phosphate domains of apatite crystals, which were caused by the crystal maturation temperature. A profound effect on mineral dissolution by pH in the culture medium was also shown. Low acidity considerably increased mineral dissolution, whereas a slight alkalinity totally blocked mineral dissolution. There was little difference in the mineral dissolution behavior of osteoclasts near the physiologic pH. In addition, it was determined whether mineral dissolution by osteoclasts was dependent on the destruction of the organic matrix. Nocodazole was introduced to inhibit the secretion of hydrolytic enzymes, and acetazolamide was added to inhibit acid production by the osteoclasts. There was no significant change as a result of nocodazole addition on mineral dissolution or by the addition of acetazolamide on degradation of collagen. These results indicate that small changes in the physicochemical properties of apatite crystals can decrease resorption by osteoclasts, which can be highly activated at low pH. These results also suggest that mineral dissolution and organic degradation by osteoclasts are self-regulating.

Sonographic features of breast abscesses with emphasis on "hypoechoic rim" sign

BACKGROUND

There are only limited reports on the ultrasound (US) features of breast abscess. The purpose of this paper is to review the US features of breast abscess with emphasis on "hypoechoic rim" sign which is more commonly seen in chronic abscess.

METHODS

In a period of 10 years, 20,998 patients were referred for breast US examinations. Medical records identified 204 patients in whom breast abscess was diagnosed. All patients were examined using high-resolution real-time US scanners. The initial ultrasound reports and hard copy images were all carefully reviewed. The grading of the echogenicity of the abscess was classified from grade 0 to grade 5. The contours of the lesions were described as smooth, macrolobulated, microlobulated, irregular, zigzag, spiculate or indistinct. The wall thickness was measured to document the presence of "hypoechoic rim" which denoted a wall thickness greater than 2 mm. The associated findings and other acoustic phenomena related to the lesion were recorded.

RESULTS

One hundred and thirty-six patients (136/204) having specific aspiration and/or biopsy/histopathological results were included in the study. All of the 136 patients showed abnormal US findings (100%). Most lesions showed grade 1 or grade 2 echogenicity (117, 86%). The contour of the abscess was usually smooth (42, 31%), macrolobulated (42, 31%), or irregular (22, 16%). A hypoechoic rim was noticed in 18 lesions (13%). Focal skin thickening was chiefly noticed in 91% of superficial abscesses (39/43) and 17% of intramammary abscesses (14/84). Diffuse skin thickening was exclusively evident in the breasts coexisting with mastitis. Hypoechoic interstitial streaks were not a common finding (7%), occurring in acute abscesses. The other findings included surrounding hypoechoic amorphous tissue (26%), posterior wall enhancement (71%), distal enhancement (60%) and lateral shadows (57%).

CONCLUSIONS

US plays an important role in confirmation of the clinical diagnosis of breast abscess and aids significantly in the management of inflammatory breast diseases. Presence of the hypoechoic rim surrounding a fluid space or a central area of low-level echoes (i.e., grade 1 to grade 3) is indicative of a chronic abscess.

Interferon-alpha treatment of chronic hepatitis C in children with hemophilia

BACKGROUND

In children with hemophilia, hepatitis C virus (HCV) is the major cause of chronic liver disease. In this study, long-term efficacy of interferon-alpha was studied to determine the factors that predict a sustained response to interferon therapy in young children with hemophilia who have chronic hepatitis C.

METHODS

Seventeen Korean children with hemophilia and chronic hepatitis C were treated with 3.7 million units/m2 of interferon-alpha2a three times weekly for 6 months. Liver biopsy, pretreatment serum HCV RNA quantitation with competitive reverse transcription assay, and HCV genotyping with reverse hybridization assay were performed.

RESULTS

Hepatitis C virus genotypes 1a, 1b, and 2a were found in three (18%), five (29%), and six (35%) patients, respectively. Interferon-alpha was well tolerated, and the frequency of bleeding did not increase. Of the 17 patients, 7 (41%) had a sustained response for 3 years after the end of therapy. Patients with a sustained response had lower pretreatment serum HCV RNA levels. One (13%) of eight patients with genotype 1 and five (83%) of six with genotype 2 had a sustained response (P < 0.05).

CONCLUSIONS

Interferon-alpha treatment of chronic hepatitis C in children with hemophilia was safe and effective in producing sustained responses. The pretreatment serum HCV RNA level and viral genotype may be predictive factors for sustained response to interferon therapy.

Clinical application of NMP22 and urinary cytology in patients with hematuria or a history of urothelial carcinoma

For evaluation of the clinical application of immunoassay for nuclear matrix protein 22 (NMP22 immunoassay) and urinary cytology for early diagnosis and detection of bladder cancer in patients with hematuria and/or a previous history of bladder cancer, 209 urine samples obtained from 137 patients presenting episodes of hematuria or a history of bladder cancer were assayed for NMP22 levels and/or prepared for cytology examination. Biopsy was performed when any visible tumor was identified during cystoscopy examination. The median NMP22 concentrations measured in samples taken from patients with active bladder cancer, from patients with a history of bladder cancer but no active disease, from patients with hematuria, and from healthy volunteers were 18.95, 5.45, 6.39, and 3.75 U/ml, respectively. The urinary NMP22 level recorded for patients with urothelial carcinoma was significantly higher than that noted for individuals without active disease. The sensitivity of the NMP22 assay and of urinary cytology in diagnosing bladder cancer was 69% and 67%, respectively. In contrast, the specificity of these two diagnostic modalities reached 72% and 93%, respectively. The NMP22 assay is slightly more sensitive but less specific than urinary cytology in detecting bladder cancer. This study indicates that determination of urinary NMP22 levels is a useful and noninvasive tool for the detection of bladder cancer because of its high sensitivity. The urinary NMP22 assay may be used as a first-line routine screening method; however, it cannot replace the use of urinary cytology because of its lower specificity.

Thin film of low-crystalline calcium phosphate apatite formed at low temperature

Surface modification of biomaterials to improve biocompatibility without changing their bulk properties is desired for many clinical applications and has become an emerging technology in biomaterial research and industry. In the present study, a simple method of coating the solid surfaces of metals, organic tissue matrices, glasses, inorganic ceramics as well as organic polymers with a thin film of low-crystalline apatite crystals (LCA) was developed. Acidic solution containing calcium and phosphate ions was neutralized with alkaline solution to form calcium phosphate precipitates at low temperature. Precipitates of solid calcium phosphate particles were, then, removed by filtration. Concentration of free ions in the filtered ion solution which were not involved in the formation of calcium phosphate precipitate was high enough to induce the heterogeneous nucleation on the solid surfaces at low temperature. Thin layers of calcium phosphate crystals were formed on the surfaces of metals, glasses, inorganic ceramics, organic polymers including hydrophobic ones, and biological tissue matrices with this solution. The thin layer of crystals consisted of poorly crystalline calcium phosphate apatite crystals which contain high amount of labile ions like bone crystals and did not dissolve in the physiologic solutions. Various cells attached to this crystal layer and proliferated well.

Aberrant left brachiocephalic vein: CT imaging findings and embryologic correlation

Computed tomography was utilized to evaluate aberrant left brachiocephalic vein (ALBCV), an infrequently discussed congenital vascular anomaly among Chinese people. Associated vascular variation and possible embryonic correlation are discussed. Since 1990, a total of 14 cases of ALBCV have been reported in patients receiving CT scan of chest, and was mainly an incidental diagnosis. One case was confirmed angiographically and two others were confirmed by magnetic resonance imaging. Emphasis was placed on the entry of the azygos vein into the superior vena cava (SVC), the length of the SVC, and the presence of other cardiovascular abnormalities. Of the 14 cases of ALBCV, the level of azygos vein entry was higher than the origin of the SVC in 7 cases: 4 were approximately the same level and 3 were lower. The average length of the SVC was approximately 5. 6 cm shorter than that of the general population, which is approximately 7.0 cm. Three cases had associated vascular anomaly. Most cases of ALBCV had azygos vein drainage level higher than or equal to the origin of the SVC. Right-sided aorta is one of the causes giving rise to the ALBCV during embryonic development. The CT scan remains a definitive diagnostic modality for ALBCV.

Fine needle aspiration cytodiagnosis of liver tumors. Results obtained with Riu's stain

OBJECTIVE

To present our experience with liver fine needle aspiration (FNA) diagnosis based on Riu's stain.

STUDY DESIGN

We reviewed a total of 322 liver fine needle aspirates from 286 patients seen in a seven-year period from April 1990 to April 1997 at Koo Foundation Sun Yat-Sen Cancer Center, Taipei. Surgical and/or clinical follow-up was available for confirmation in 292 aspirates.

RESULTS

The cytologic diagnosis was categorized into four groups: benign in 81 cases, suspicious in 13, malignant in 225, and inadequate specimen in 3 cases. There were 16 false negative and no false positive diagnoses. Two suspicious aspirates were negative. Our results showed a sensitivity of 93.3% and a specificity of 100% for the detection of malignancy. If suspicious cases were considered positive, the specificity decreased to 95.1%, while the sensitivity increased to 93.6%. Among 87 hepatocellular carcinomas (HCCs) in our series, correct FNA diagnosis was made in 84 cases with an accuracy of 96.6%. Out of 135 cases of non-HCCs, 1 was incorrectly diagnosed. The accuracy of identifying a liver malignancy as non-HCC was 99.3%.

CONCLUSION

Cytologic features of HCC are well demonstrated by Riu's stain, with high accuracy in identifying them. Liver FNAs using Riu's stain combined with cell block study and clinicopathologic correlation can achieve very high sensitivity and specificity in the detection of hepatic malignancies.

Triangular fibrocartilage perforations with bilateral negative ulnar variant wrists: a case report

Triangular fibrocartilage (TFC) constitutes the major part in the triangular fibrocartilage complex, which stabilizes the distal radioulnar joint and functions as a cushion for axial compression forces. Tears in the TFC are often encountered with positive ulnar variance and regarded as part of a degenerative process of the ulnocarpal joint. They are occasionally seen as the result of trauma and are less likely to be found in a young population, especially in those who are in the first two decades of life, without causative traumatic injury. We report the case of a 12-year-old boy with bilateral negative ulnar variances with incidental findings of TFC tears in both wrists. This is a rare case, as he had no history of a traumatic event.

Riu's stain and the cytologic diagnosis of thyroid fine-needle aspiration: a single cancer center experience

Riu's stain, a Romanowsky-type stain, has been in use in Taiwan over the past 40 years. In order to determine whether it is useful for the diagnosis of thyroid disease in thyroid fine-needle aspiration, we reviewed 254 of these aspirates obtained between April 1990 and June 1996 from patients seen in Koo Foundation Sun Yat-Sen Cancer Center in Taipei. Surgical follow-up was available for confirmation in 61 aspirations. The cytologic diagnosis was categorized into four groups: benign, 174; suspicious, 30; malignant, 41): and inadequate specimen, 9. There were two false-negative and no false-positive diagnoses. Our results showed a sensitivity of 93.5% and a specificity of 100% for the detection of malignancy. If suspicious cases were considered positive, the specificity decreased to 55%, while the sensitivity increased to 95%. We conclude that Riu's stain is a reliable quick stain in the diagnosis of thyroid malignancy. Compared to Papanicolaou stain, it shortens the time needed for a cytopathologist to reach a diagnosis. Papanicolaou stain can be reserved for confirmation.

Structural aspects of the reversal phase of alveolar bone remodelling

The ultrastructure of the reversal line during alveolar bone remodelling was investigated in the rat. Surface bone remodelling along the periosteum of the mandible was induced by the extraction of opposing maxillary molars. With transmission EM the reversal line was seen to be composed of a superficial electron-dense amorphous layer and a deep filamentous layer at 7 d after extraction. The reversal line exhibited strong alkaline phosphatase activity and contained acid mucopolysaccharide. Scanning EM of the surface of the line, exposed by sonication in distilled water, showed papillary structures, the surface of which appeared granular and exhibited a crystalline appearance. The tips of collagen fibrils of new bone were attached to the top of the papillae in the front area of bone formation. It is suggested that the reversal line is involved in the coupling of bone resorption and formation.

Anatomical observation on draining patterns of saphenous tributaries in Korean adults

This study was done to identify the normal and variants of saphenous tributaries in Korean adults. The pattern of confluence of saphenous tributaries, medial accessory saphenous, lateral accessory saphenous, superficial epigastric, superficial circumflex iliac and superficial external pudendal veins, was carefully examined in 249 lower limbs (right, 129; left, 120) of embalmed Korean cadavers (73 males & 56 females). The medial accessory saphenous vein drained into the great saphenous vein directly (in 82.3%) or by a common trunk (in 17.7%) with the superficial epigastric or superficial external pudendal vein. The lateral accessory saphenous vein entered the great saphenous (in 67.1%) or the femoral vein (in 32.9%) directly or, forming a common trunk with other saphenous tributaries. The superficial epigastric vein joined the great saphenous (in 77.1%) or the femoral vein (in 22.9%) directly or, by a common trunk with other saphenous tributaries. The superficial circumflex iliac vein reached the great saphenous (in 83.1%) or the femoral vein (in 16.9%) directly or, by a common trunk with other saphenous tributaries. The superficial external pudendal vein opened into the great saphenous (in 95.2%) or the femoral vein (in 4.8%) directly or by a common trunk with other saphenous tributaries. In Koreans, the incidence of the normal pattern of saphenous tributaries was 23.7% and in 76.3% any one of variant saphenous tributaries entered the femoral or the great saphenous vein by a common trunk with other saphenous tributaries.

Variations of the ventral rami of the brachial plexus

We studied the variations in the ventral rami of 152 brachial plexuses in 77 Korean adults. Brachial plexus were composed mostly of the fifth, sixth, seventh and eighth cervical nerves and the first thoracic nerve (77.0%). In 21.7% of the cases examined, the fourth, fifth, sixth, seventh and eighth cervical and the first thoracic nerves contributed to the plexus. A plexus composed of the fourth, fifth, sixth, seventh and eighth cervical and the first and second thoracic nerves, and a plexus composed of the fifth, sixth, seventh eighth cervical nerves were also observed. The plexuses were classified into three groups according to cephalic limitation, and the plexus of group 2 in which the whole fifth cervical nerve enters the plexus, were observed the most frequent. The average diameter of the sixth and the seventh cervical ventral rami of the plexus was greatest and that of the fifth cervical was smallest. The largest nerve entering the plexus was the sixth or the seventh cervical nerve in about 79% of cases. The dorsal scapular nerve originated from the fifth cervical ventral ramus in 110 cases (75.8%). The long thoracic nerve was formed by joining of roots from the fifth, sixth, and seventh cervical nerves in 76.0% of cases. Also, a branch to the phrenic nerve, the suprascapular nerve, a nerve to the pectoralis major muscle and a nerve to the subscapular muscle arising from the ventral rami of the plexus were observed.

Cloning of alpha 1(IV) and alpha 2(IV) collagen cDNAs from rabbit corneal endothelial cell RNA

To understand the role of type IV collagen in embryogenesis, regeneration, and tissue repair of the cornea at the molecular level, the authors isolated clones coding for rabbit alpha 1(IV) and alpha 2(IV) chains from a cDNA library constructed with rabbit corneal endothelial cell RNA. The isolated alpha 2(IV) cDNA clones encode a part of a 5' untranslated region, the signal peptide, the 7S domain, part of the triple-helical domain, and the entire carboxyl-terminal nontriple-helical (NC1) domain. By cross hybridization, using one of the alpha 2(IV) cDNA inserts, a cDNA clone encoding the alpha 1(IV) chain was isolated from a lambda gt10 library primed with oligo(dT). The clone covered a short portion of the triple-helical domain, the entire NC1 domain, and a short 3' untranslated region. The nucleotide-sequence analysis of these clones provides, for the first time to the authors' knowledge, the primary structure of the carboxyl-terminal portion of both rabbit alpha 1(IV) and alpha 2(IV) collagen chains. Between the alpha 1(IV)NC1 and the alpha 2(IV)NC1, 61% and 66% sequence similarities were observed at the amino acid and nucleotide levels, respectively. The locations of all the 12 cysteinyl residues were conserved in the two NC1 sequences.

Immunohistochemical localization of keratin in the taste buds of rat vallate papillae

Keratin detected with anti-human whole keratin serum, raised in rabbits by injection of the isolated human whole keratin, was used as a histologic marker to study the origin of the cells in taste buds. Rat vallate papillae, including surrounding tissue, were processed for indirect immunofluorescent staining of ketatin. In the taste buds, most basal cells and some of the elongated cells were immunoreactive with anti-keratin serum, showing that most taste-bud cells, if not all, originate from cells of epithelial origin.