Piceatannol, a natural hydroxylated analog of resveratrol, promotes nitric oxide release through phosphorylation of endothelial nitric oxide synthase in human endothelial cells

OBJECTIVE

Endothelial dysfunction associated with many cardiovascular diseases is largely due to reduced nitric oxide (NO) derived from endothelial NO synthase (eNOS). Piceatannol (trans-3,4,3',5'-tetrahydroxystilbene; Pic) is reported to have cardiovascular therapeutic effects. However, the cellular and molecular mechanisms underlying the cardioprotective effects of Pic are still unclear. Here, we investigated whether Pic could influence endothelial NO release in human umbilical vein endothelial cells (HUVECs).

MATERIALS AND METHODS

In HUVECs exposed to Pic, NO production and phosphorylation of eNOS and protein kinase B (Akt) were determined by using a commercially available NO assay kit and Western blot analysis, respectively.

RESULTS

Pic stimulated dose- and time-dependent NO production via eNOS phosphorylation. Pic also stimulated dose-dependent phosphorylation of Akt. Interestingly, NO production and eNOS phosphorylation in response to Pic were significantly abolished by the phosphoinositide 3-kinase (PI3K)/Akt inhibitor LY294002.

CONCLUSIONS

Pic is capable of inducing eNOS phosphorylation and the subsequent NO release, presumably, by activating PI3K/Akt pathway. The potential efficacy of Pic, a natural hydroxylated analog and a metabolite of resveratrol, may aid in the prevention of cardiovascular diseases characterized by endothelial dysfunction.

Long-term efficacy of biofeedback therapy in patients with dyssynergic defecation: results of a median 44 months follow-up

BACKGROUND

The beneficial effect of biofeedback therapy (BFT) over a period of more than 2 years has not been studied in a large group of patients. The aim of this study was to evaluate the long-term efficacy of BFT for dyssynergic defecation (DD).

METHODS

We evaluated the results for 347 consecutive constipated patients with DD who underwent BFT for a median of five sessions between 2004 and 2009. Initial responses were assessed immediately after the completion of BFT. A responder was defined as a subject with at least a three-point improvement from before to after BFT on an 11-point global bowel satisfaction (GBS) scale, or a two-point improvement if the baseline GBS was more than six points. The probability of remaining a responder was estimated by non-parametric maximum likelihood estimation.

KEY RESULTS

The initial response rate to BFT was 72.3% (n = 251), Parkinson's disease and higher baseline GBS scores were associated with initial non-response. The long-term efficacy of BFT was analyzed in 103 patients who were followed up for more than 6 months; the initial effects of BFT were maintained in 85 of the patients (82.5%) during a median of 44 months of follow-up (IQR = 12-68). The probability of remaining a responder was 60% at 2 years, and 58% at 5 years.

CONCLUSIONS & INFERENCES

The efficacy of BFT is maintained for more than 2 years after BFT in a considerable proportion of constipated patients with DD. BFT is effective and durable treatment for managing DD.

Timing of reversal with respect to three nerve stimulator end-points from cisatracurium-induced neuromuscular block

After elective ear surgery with cisatracurium neuromuscular blockade, 48 adults were randomly assigned to receive neostigmine: (a) at appearance of the fourth twitch of a 'train-of-four'; (b) at loss of fade to train-of-four; or (c) at loss of fade to double-burst stimulation, all monitored using a TOF-Watch SX® on one arm. For each of these conditions, the recovery from train-of-four (TOF) ratio was measured in parallel objectively using a TOF-Watch SX placed on the contralateral arm. The median (IQR [range]) time from administration of reversal to a train-of-four ratio ≥ 0.9 was 11 (9-15.5 [2-28]) min, 8 (4-13.5 [1-25]) min and 7 (4-10 [2-15]) min in the three groups, respectively. This recovery time was significantly shorter when reversal was given at loss of fade to double-burst stimulation (c), than when given at the appearance of the fourth twitch (a), p = 0.046. However, the total time to extubation may be unaffected as it takes longer for fade to be lost after double-burst stimulation than for four twitches subjectively to appear.

A case of panniculitis caused by Mycobacterium massiliense mimicking erythema induratum

Among nontuberculosis mycobacteria (NTM), rapidly growing mycobacteria (RGM) are the most common causative agents of soft tissue infection. Mycobacterium massiliense, a new species of NTM, was isolated in 2004. Due to the lower virulence of RGM, M. massiliense infection is rare in the general population. Here, we report a case of multiple infective panniculitis, due to M. massiliense, mimicking erythema induratum in a patient with Cushing syndrome. The organism was identified using traditional mycobacterial culturing and staining methods as well as molecular approaches, including erythromycin ribosome transferase gene polymerase chain reaction. The patient was treated with clarithromycin for 9 months, based on antibiotic susceptibility testing.

Berberine induces apoptosis via ROS generation in PANC-1 and MIA-PaCa2 pancreatic cell lines

Pancreatic cancer is the fourth leading cause of cancer death. Gemcitabine is widely used as a chemotherapeutic agent for the treatment of pancreatic cancer, but the prognosis is still poor. Berberine, an isoquinoline alkaloid extracted from a variety of natural herbs, possesses a variety of pharmacological properties including anticancer effects. In this study, we investigated the anticancer effects of berberine and compared its use with that of gemcitabine in the pancreatic cancer cell lines PANC-1 and MIA-PaCa2. Berberine inhibited cell growth in a dose-dependent manner by inducing cell cycle arrest and apoptosis. After berberine treatment, the G1 phase of PANC-1 cells increased by 10% compared to control cells, and the G1 phase of MIA-PaCa2 cells was increased by 2%. Whereas gemcitabine exerts antiproliferation effects through S-phase arrest, our results showed that berberine inhibited proliferation by inducing G1-phase arrest. Berberine-induced apoptosis of PANC-1 and MIA-PaCa2 cells increased by 7 and 2% compared to control cells, respectively. Notably, berberine had a greater apoptotic effect in PANC-1 cells than gemcitabine. Upon treatment of PANC-1 and MIA-PaCa2 with berberine at a half-maximal inhibitory concentration (IC₅₀), apoptosis was induced by a mechanism that involved the production of reactive oxygen species (ROS) rather than caspase 3/7 activation. Our findings showed that berberine had anti-cancer effects and may be an effective drug for pancreatic cancer chemotherapy.

Lumbar hernia in South Korea: different from that in foreign literature?

PURPOSE

This study aimed to analyze the clinical features of lumbar hernia reported in South Korea and compare these features with those reported in foreign literature.

METHODS

From January 1968 through December 2013, 13 cases reported in South Korea were included in the study. The variables compared were age, sex, main symptoms at hospital visit, etiology, location, herniated contents, lateralization, defect size, diagnostic methods, surgical methods, surgical opinions, and recurrence.

RESULTS

In the South Korean cases, women outnumbered men (3.3:1) and no significant differences were found in the herniated side (left:right, 1.1:1). In contrast, in the foreign cases, men outnumbered women (3:1) and left-sided hernia was dominant (2:1). Moreover, in most of the foreign cases, patients were aged 50-70 years, whereas in the South Korean cases, none of the patients were in their 50 s. However, no substantial differences were found in etiology, anatomical locations, symptoms, and herniated contents.

CONCLUSION

This research revealed that few clinical features of lumbar hernias in South Korea differ from those reported in foreign literature. Thirteen cases were analyzed in the present study, and results obtained from such a small sample size cannot be generalized with certainty. Therefore, more cases should be collected for a definitive analysis. Despite this limitation, this study is important because it is the first attempt to collect and analyze the clinical features of lumbar hernia in South Korea. This study will serve as a basis for future studies investigating the clinical features of lumbar hernia cases in South Korea.

Development of multiplex PCR assay for simultaneous detection of Salmonella genus, Salmonella subspecies I, Salm. Enteritidis, Salm. Heidelberg and Salm. Typhimurium

AIMS

The aim of this research was to develop multiplex PCR assay that could simultaneously detect Salmonella genus, Salmonella subsp. I, Salm. Enteritidis, Heidelberg and Typhimurium because these Salmonella serovars are the most common isolates associated with poultry products.

METHODS AND RESULTS

Five primers were utilized to establish multiplex PCR and applied to Salmonella isolates from chickens and farm environments. These isolates were identified as Salmonella subsp. I and 16 of 66 isolates were classified as Salm. Enteritidis, while Heidelberg or Typhimurium was not detected. We also spiked three Salmonella strains on chicken breast meat to evaluate the specificity and sensitivity of multiplex PCR as well as qPCR to optimize quantification of Salmonella in these samples. The optimized multiplex PCR and qPCR could detect approx. 2·2 CFU of Salmonella per gram after 18 h enrichment.

CONCLUSIONS

The multiplex PCR and qPCR would provide rapid and consistent results. Also, these techniques would be useful for the detection and quantification of Salmonella in contaminated poultry, foods and environmental samples.

SIGNIFICANCE AND IMPACT OF THE STUDY

The strategy for the rapid detection of Salmonella serovars in poultry is needed to further reduce the incidence of salmonellosis in humans. The optimized multiplex PCR will be useful to detect prevalent Salmonella serovars in poultry products.

Body fluid cellular analysis using the Sysmex XN-2000 automatic hematology analyzer: focusing on malignant samples

INTRODUCTION

The majority of previous studies on body fluid (BF) mode of automatic hematology analyzer used nonmalignant BF samples. Here, we evaluated the BF mode on the recently launched Sysmex XN for counting blood cells, especially for malignant samples.

METHODS

A total of 405 BF specimens including 125 malignant samples were analyzed using both the automated method and manual microscopy.

RESULTS

In non-cerebrospinal fluids (CSF) samples, there was an agreement between two methods for WBC, RBC, polymorphonuclear, and mononuclear cell counts (R(2)  = 0.96, 0.94, 0.88, and 0.88, respectively). CSF samples showed slightly poorer correlations than other fluids. Exclusion of malignant samples significantly improved correlations in non-CSF samples, but not in CSF samples. High fluorescence-BF (HF-BF) cells were identified significantly more frequently in malignant samples compared to benign samples (17.8 and 4.15/100 WBC, respectively; P < 0.001). Receiver operating characteristic curve analysis demonstrated an HF-BF cell AUC of 0.791 using a cutoff value of 6.9/100 WBC for detecting malignant samples.

CONCLUSION

The BF mode on the Sysmex XN could be an alternative method for the manual counts in the BF analysis with a few drawbacks. However, if a concentration of HF-BF cells is greater than the given threshold, microscopic examination should be subsequently performed.

Influence of Cavity Preparation, Light-curing Units, and Composite Filling on Intrapulpal Temperature Increase in an In Vitro Tooth Model

This study examined the effect of both the tooth substance and restorative filling materials on the increase in pulp chamber temperature when using light-curing units with different power densities.

The tip of a temperature sensor was positioned on the pulpal dentinal wall of the buccal side of a maxillary premolar. Metal tubes were inserted in the palatal and buccal root of the tooth, one for water inflow and the other for water outflow. Polyethylene tubes were connected from the metal tubes to a pump to control the flow rate. For the unprepared tooth group (group 1), the tooth was light-cured from the buccal side using two light-curing units (three curing modes): the VIP Junior (QTH, BISCO, Schaumburg, IL, USA) and the Bluephase LED light-curing units (two modes: LEDlow and LEDhigh; Ivoclar Vivadent, Schaan, Liechtenstein). The power densities of each light-curing unit for the LEDlow, QTH, and LEDhigh modes were 785 mW/cm2, 891 mW/cm2, and 1447 mW/cm2, respectively. All light-curing units were activated for 60 seconds. For the prepared tooth group (group 2), a Class V cavity, 4.0 mm in width by 4.0 mm in height by 1.8 mm in depth in size, was prepared on the buccal surface of the same tooth for the temperature measurement. The light-curing and temperature measurements were performed using the same methods used in group 1.

The cavity prepared in group 2 was filled with a resin composite (Tetric N Ceram A3 shade, Ivoclar Vivadent) (group 3) or a flowable composite (Tetric N Flow with A3 shade, Ivoclar Vivadent) (group 4). The light-curing and temperature measurements were performed for these groups using the same methods used for the other groups.

The highest intrapulpal temperature (TMAX) was measured, and a comparison was conducted between the groups using two-way analysis of variance with a post hoc Tukey test at the 95% confidence level.

The TMAX values were as follows: 38.4°C (group 1), 39.0°C (group 2), 39.8°C (group 3), and 40.3°C (group 4) for the LEDlow mode. For the QTH mode, the TMAX values were 40.1°C (group 1), 40.4°C (group 2), 40.9°C (group 3), and 41.4°C (group 4). For the LEDhigh mode, the TMAX values were 43.3°C (group 1), 44.5°C (group 2), 44.7°C (group 3), and 45.3°C (group 4). The statistical analysis revealed the following: the TMAX values were arranged by mode in the following manner: LEDlow &lt; QTH &lt; LEDhigh (p&lt;0.05) and group 1 &lt; group 2 ≤ group 3 ≤ group 4 (p&lt;0.05).

Bioinformatic investigation of the cost management strategies of five oral microbes

Some amino acids are more energetically costly to synthesize de novo, therefore many microbes have evolved to regulate the metabolic expenditure of the cell and reduce the energy burden of extracellular unrecyclable proteins. Several oral bacterial species take up amino acids and peptides obtained from proteolysis of host proteins and hence do not rely only on de novo synthesis. The aim of this study was to investigate if five oral bacterial species implement cost management strategies to reduce the energy burden of extracellular unrecyclable proteins. Since the relative de novo amino acid synthesis costs are proportional to the masses of the amino acids, the energy costs of producing proteins were assessed by calculating the mean amino acid mass for each protein. For Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, Prevotella intermedia and Streptococcus sanguinis, the outer membrane/extracellular proteins are made up of a much larger percentage of lower average mass amino acids whereas cytoplasmic proteins are made up of a larger proportion of higher average mass amino acid residues. These results are consistent with the five oral bacterial species employing energy-saving mechanisms in the production of extracellular unrecyclable proteins. Interestingly, the P. gingivalis and S. sanguinis genomes exhibited significantly lower predicted mean amino acid masses compared with those of the genomes of the other three species, suggesting that this may provide them with an energy advantage with respect to protein biosynthetic cost.

Technical tips and issues of biliary stenting, focusing on malignant hilar obstruction

In patients with inoperable hilar cholangiocarcinoma (HCCA), palliative endoscopic or percutaneous drainage provides benefits in terms of symptomatic improvement and quality of life. Endoscopic biliary stent placement is considered the gold standard, with metal stents preferred over plastic stents in patients with more than three months of life expectancy. However, the endoscopic management of advanced hilar obstruction is often more challenging and complex than distal malignant biliary obstructions. Recently, the Asia-Pacific working group on hepatobiliary cancers produced consensus recommendations on the use of endoscopic vs. percutaneous drainage and unilateral vs. bilateral drainage in the management of HCCA. However, these guidelines must be weighed against context-specific information, such as the volume of liver drainage required, life expectancy of the patient, and the available expertise. In this literature review, we describe the issues commonly encountered during endoscopic biliary stenting for malignant hilar obstruction and provide technical guidance to improve success rates and patient outcomes.

Measurement of the Internal Adaptation of Resin Composites Using Micro-CT and Its Correlation With Polymerization Shrinkage

In the present study, the internal adaptation of dentin-composite interfaces with various resin composite materials under conditions of thermomechanical loading was analyzed nondestructively using micro–computed tomography (micro-CT), and these results were compared with analyses of microgaps after sectioning. Additionally, the correlation of internal adaptation with polymerization shrinkage strain and stress was evaluated.

Four nonflowable resins, Gradia Direct (GD), Filtek P90 (P9), Filtek Z350 (Z3), and Charisma (CH), and two flowable resins, SDR (SD) and Tetric N-Flow (TF) were used. First, the polymerization shrinkage strain and stress were measured. Then, Class I cavities were prepared in 48 premolars. They were divided randomly into six groups, and the cavities were filled with composites using XP bond. To evaluate the internal adaptation, tooth specimens were immersed in a 25% silver nitrate solution, and micro-CT analysis was performed before and after thermomechanical loading. The silver nitrate penetration (%SP) was measured. After buccolingual sectioning and rhodamine penetration of the specimen, the rhodamine penetration (%RP) was measured using a stereo-microscope. One-way analysis of variance was then used to compare the polymerization shrinkage strain, stress, %SP, and %RP among the groups at a 95% confidence level. A paired t-test was used to compare the %SP before and after thermomechanical loading. Pearson correlation analysis was used to compare the correlation between polymerization shrinkage strain/stress and %SP or %RP to a 95% confidence level.

Evaluation of the polymerization shrinkage strain demonstrated that P9 &lt; Z3 ≤ GD &lt; CH ≤ SD &lt; TF (p&lt;0.05); similarly, evaluation of the polymerization shrinkage stress showed that P9 ≤ GD ≤ Z3 ≤ CH ≤ SD &lt; TF (p&lt;0.05). The %SP showed that P9 ≤ GD ≤ Z3 &lt; CH ≤ SD &lt; TF (p&lt;0.05) before loading and that P9 ≤ GD ≤ Z3 ≤ CH ≤ SD &lt; TF (p&lt;0.05) after loading. There was a significant difference between the before-loading and after-loading measurements in all groups (p&lt;0.05). Additionally, there was a positive correlation between the %SP and the %RP (r=0.810, p&lt;0.001).

Conclusively, the polymerization shrinkage stress and strain were found to be closely related to the internal adaptation of the resin composite restorations. The newly proposed model for the evaluation of internal adaptation using micro-CT and silver nitrate may provide a new measurement for evaluating the internal adaptation of restorations in a nondestructive way.

Abstract P2-06-05: Association of promoter methylation status of the FHIT gene and Fhit expression with HER2/neu status in breast cancer

Purpose: Aberrant DNA methylation has been recognized to contribute to breast carcinogenesis, and promoter hypermethylation of many tumor suppressor genes has been correlated with decreased gene expression. The fragile histidine triad (FHIT) gene is a putative tumor suppressor gene in breast and other cancers, and loss of Fhit expression has been observed in breast cancers. The aim of this study was to evaluate the association between methylation of the FHIT gene and its expression in breast cancer, and to investigate whether methylation and expression of the FHIT gene would correlate with clinicopathological characteristics in relation to human epidermal growth factor receptor 2 (HER2) status.

Methods: Pyrosequencing of bisulfite treated DNA was performed to study the methylation status of the FHIT gene in 60 breast cancer samples from Korean women obtained at Daegu Catholic University Hospital. We examined the expression of FHIT using tissue microarrays by immunohistochemical staining. Association between the methylation status of the FHIT gene and its expression was analyzed, and the relationship between the FHIT expression and the clinicopathological characteristics of the patients was evaluated.

Results: FHIT methylation was detected in 96.7% and positive expression rate of Fhit was 87.3% of the patients. The mean methylation level of the FHIT gene was associated with intratumoral inflammation. Methylation level of the FHIT gene had no significant differences according to molecular subtypes. Loss of Fhit expression was associated with large tumor size, basal-like subtype and positive expression of EGFR. In HER2-negative breast cancers, loss of Fhit expression was significantly associated with tumor size, estrogen receptor status and Ki-67 proliferation index. There was no significant correlation between methylation of the FHIT gene and its expression in this study.

Conslusion: Our study revealed that loss of Fhit expression in breast cancer is associated with poor prognostic features, although there is no significance association between the FHIT gene methylation and Fhit expression. We found that in HER2-negatvie breast cancers, loss of Fhit expression was associated with poor prognostic features. These results support the possibility of potential complementation between HER2 and the Fhit pathway. The clinical significance of our findings needs to be further evaluated in larger cohorts with longer follow-up.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-06-05.

Safety of transorally-inserted anvil for esophagojejunostomy in laparoscopic total gastrectomy

BACKGROUND

To assess the safety of transorally-inserted anvil (TOA) for use during esophagojejunostomy (EJ) reconstruction during laparoscopic total gastrectomy (LTG).

METHODS

Between March 2009 and December 2011, 39 consecutive open total gastrectomies (OTGs) and 36 LTGs using TOA for gastric cancer were comparatively evaluated. We investigated postoperative complications, using the Clavien-Dindo classification. To evaluate the effect of a learning period in using TOA for LTG, we also investigated shifts in the patterns of complications and changes in total operation time over the course of the study.

RESULTS

The patient characteristics at baseline were not different between both groups, except for the extent of lymphadenectomy (P < 0.001) and depth of tumor invasion (P = 0.003). Multivariate analysis revealed that TOA usage elevated the occurrence of infectious complications significantly (OR = 3.32, P = 0.042), but was not associated with EJ-related complications. TOA usage did not need a learning period for the length of time required to complete the operation, or the likelihood of developing an EJ-related or infectious complication.

CONCLUSIONS

TOA use for EJ during LTG is relatively simple and easy enough not to require a learning period for surgeons. This procedure did not elevated the occurrence of EJ-related complications compared to circular stapling in open surgery, but it does require special prevention efforts to avoid infectious complications.

False negative results in axillary lymph nodes by ultrasonography and ultrasonography-guided fine-needle aspiration in patients with invasive ductal carcinoma

PURPOSE

For preoperative evaluation of ALN status using various methods, axillary US and subsequent US-FNA targeting the LNs suspicious for metastasis are the most widely used methods. The purpose of our study was to assess the rate of false-negative results at preoperative ultrasonography (US) and ultrasonography guided fine needle aspiration (US-FNA) of axillary lymph nodes (ALNs) in breast cancer patients and the number of false-negative lymph nodes, and to evaluate factors related to ALN false negative results in US and/or US-FNA in patients diagnosed with invasive ductal carcinoma.

MATERIALS AND METHODS

Among 317 patients who underwent surgery for invasive ductal carcinoma during 2009 in Severance hospital, 237 patients had no reported ALN metastasis on preoperative US-FNA and US. We retrospectively reviewed the subsequent surgical pathology and clinicopathologic findings and assessed the rate of false-negative results from US and US-FNA of ALN and the number of false-negative lymph node. We performed univariate analysis and multivariate logistic regression analysis to evaluate the relationships between variable clinicopathologic factors (T-stage, position of ALN, hormone receptors, histologic grade, lymphovascular invasion (LVI) and performance of FNA) and cytologic results (false-negative result; FNALN and true negative result; TNALN) from US and/or US-FNA of ALN.

RESULTS

The rate of false-negative results was 42.4 % (59/139) in both US and US-FNA of ALN but among them, 57.6 % (34/59) showed only one metastatic ALN. Breast cancer with FNALN on US and US-FNA was significantly related to positive estrogen receptor (p = 0.003), positive progesterone receptor (p = 0.001), and the presence of LVI (p = 0.004) in univariate analysis. In multivariate analysis, high T stages (≥ T2, odds ratio (OR) 4.007, p = 0.004) and LVI (OR 7.951, p = 0.001) showed significant correlation with FNALN on US and US-FNA.

CONCLUSION

More than half of patients with FNALN showed only one metastatic ALN. LVI and high T-stages were the most important factors attributed to FNALN on US and US-FNA in patients with invasive ductal carcinoma.

Influence of a modified propofol equilibration rate constant (k(e0)) on the effect-site concentration at loss and recovery of consciousness with the Marsh model

This study compared the predicted effect-site concentration of propofol at loss and recovery of consciousness when using target-controlled infusion devices with the same pharmacokinetic model (Marsh) but a different plasma effect-site equilibration rate constant (ke0 ), the Diprifusor(TM) (ke0 0.26 min(-1) ) and Base Primea™ (ke0 1.21 min(-1) ). We studied 60 female patients undergoing minor gynaecological surgery under general anaesthesia. Although the total dose of propofol and time until loss of consciousness were comparable, the effect-site concentration at loss of consciousness was significantly lower with the Diprifusor than with the Base Primea (1.2 (0.3) μg.ml(-1) vs 4.5 (0.9) μg.ml(-1) , respectively, p < 0.001). The effect-site concentration at recovery of consciousness was significantly higher with the Diprifusor than with the Base Primea (1.8 (0.4) μg.ml(-1) vs 1.5 (0.2) μg.ml(-1) , respectively, p = 0.01). In conclusion, the effect-site concentration of propofol differs depending on the ke0 , despite the use of the same pharmacokinetic model. Therefore, the ke0 should be considered when predicting loss and recovery of consciousness based on the effect-site concentration of propofol.

Primary and revision efficacy of cross-wired metallic stents for endoscopic bilateral stent-in-stent placement in malignant hilar biliary strictures

BACKGROUND AND STUDY AIMS

Endoscopic bilateral drainage for inoperable malignant hilar biliary strictures (HBS) using metal stents is considered to be technically difficult. Furthermore, endoscopic revision of bilateral stenting after occlusion can be challenging. This study was performed to evaluate the long-term efficacy of endoscopic bilateral stent-in-stent placement of cross-wired metallic stents in high-grade malignant HBS and planned endoscopic bilateral revision.

PATIENTS AND METHODS

A total of 84 patients with inoperable high-grade malignant HBS were enrolled from three academic tertiary referral centers. Two cross-wired metal stents were inserted using a bilateral stent-in-stent placement method. Bilateral endoscopic revision was also performed during follow-up using either identical metal stents or plastic stents. The main outcome measurements were technical and functional success, complications, stent patency, and endoscopic revision efficacy.

RESULTS

The technical and clinical success rates of endoscopic bilateral stent-in-stent placement of cross-wired metallic stents were 95.2% (80/84) and 92.9% (78/84), respectively. Median patency (range) and survival were 238 days (10-429) and 256 days (10-1130), respectively. Obstruction of primary bilateral stents occurred in 30.8% (24/78) of patients with functionally successful stent placement. The technical and clinical success rates of planned bilateral endoscopic revision for occluded stents were 83.3% (20/24) and 79.2% (19/24), respectively. For revision, bilateral metallic stents were placed in 11 patients (55.0%); the remaining patients received plastic stents.

CONCLUSIONS

Palliative endoscopic bilateral stent-in-stent placement of cross-wired metallic stents was effective in patients with inoperable HBS. Revision endoscopic bilateral stenting may be feasible and successful in cases where the primary deployed metal stents are occluded.

Femur-mounted navigation system for the arthroscopic treatment of femoroacetabular impingement

Femoroacetabular impingement stems from an abnormal shape of the acetabulum and proximal femur. It is treated by resection of damaged soft tissue and by the shaping of bone to resemble normal features. The arthroscopic treatment of femoroacetabular impingement has many advantages, including minimal incisions, rapid recovery, and less pain. However, in some cases, revision is needed owing to the insufficient resection of damaged bone from a misreading of the surgical site. The limited view of arthroscopy is the major reason for the complications. In this research, a navigation method for the arthroscopic treatment of femoroacetabular impingement is developed. The proposed navigation system consists of femur attachable measurement device and user interface. The bone mounted measurement devices measure points on head-neck junction for registration and position of surgical instrument. User interface shows the three-dimensional model of patient's femur and surgical instrument position that is tracked by measurement device. Surgeon can know the three-dimensional anatomical structure of hip joint and surgical instrument position on surgical site using navigation system. Surface registration was used to obtain relation between patient's coordinate at the surgical site and coordinate of three-dimensional model of femur. In this research, we evaluated the proposed navigation system using plastic model bone. It is expected that the surgical tool tracking position accuracy will be less than 1 mm.

Interrupting gel layer between Double cuffs prevents fluid leakage past tracheal tube cuffs

BACKGROUND

Current tracheal tubes (TTs) cannot guarantee a perfect seal against pulmonary aspiration of upper airway secretions. The purpose of this study was to investigate whether a gel layer between the tracheal tube with double cuffs (Double cuffs) prevents fluid leakage past TT cuffs.

METHODS

In vitro fluid leakage tests were performed using the Double cuff with or without a gel layer between the two cuffs and four commercially available TTs (Euromedical Standard TT, Mallinckrodt Hi-Lo™, Microcuff, and Mallinckrodt TaperGuard™) when placed in artificial tracheas with three-different internal diameters (ID; 16, 20, and 22 mm). Blue-dyed water (5 ml) was placed above the cuff, and the extent of fluid leakage was observed for 48 h. Each test was repeated five times with new tubes at six different intracuff pressures (15, 20, 25, 30, 40, and 50 cm H2O).

RESULTS

In all of the conventional TTs and the Double cuff without a gel layer, fluid leakage was observed even at clinically acceptable intracuff pressures (25-30 cm H2O). However, in the Double cuff with a gel layer, no fluid leakage was observed for 48 h at all intracuff pressures in three-different sized artificial tracheas. At an intracuff pressure of 20 cm H2O in a 20 mm ID trachea, the average volume of injected gel was 2.0 ml. After removal of the TT, the mean volume of the remaining gel in the trachea was 0.10 ml.

CONCLUSIONS

A prototype TT with gel-layered Double cuffs completely blocked fluid leakage past the cuffs for 48 h in a bench-top model. Clinical studies are required to determine whether this TT reduces the risk of ventilator-associated pneumonia.

Physiologic load-bearing characteristics of autografts, allografts, and polymer-based scaffolds in a critical sized segmental defect of long bone: an experimental study

Background

To address the challenge of treating critical sized intercalary defects, we hypothesized that under physiologic cyclic loading, autografts, allografts, and scaffolds loaded with and without human mesenchymal stem cells (hMSCs) would have different biomechanical characteristics.

Methods

Using a rat femoral defect model, 46 rats were assigned to four groups, ie, autograft (n = 12), allograft (n = 10), scaffold (n = 13), and scaffold with hMSCs (n = 11). The scaffold groups used a 5 mm segment of scaffold composed of 80% poly-ε-caprolactone and 20% hydroxyapatite. Rats were sacrificed 4 months postoperatively, and the repairs were assessed radiographically and biomechanically.

Results

Autograft and allograft groups exhibited the most bridging callus, while the scaffold/hMSCs group had more callus than the scaffold repairs. Although signs of radiographic healing did not accurately reflect restoration of mechanical properties, addition of hMSCs on the scaffold enhanced bone formation. The scaffold alone group had significantly lower elastic and viscous stiffness and higher phase angles than other repairs and the contralateral controls. Addition of hMSCs increased the elastic and viscous stiffness of the repair, while decreasing the phase angle.

Conclusion

Further comparative analysis is needed to optimize clinical use of scaffolds and hMSCs for critical sized defect repairs. However, our results suggest that addition of hMSCs to scaffolds enhances mechanical simulation of native host bone.

Nonsteroidal anti-inflammatory drugs (NSAID) sparing effects of glucosamine hydrochloride through N-glycosylation inhibition; strategy to rescue stomach from NSAID damage

Gastrointestinal or cardiovascular complications limit nonsteroidal anti-inflammatory drugs (NSAID) prescription. Glucosamine hydrochloride (GS-HCl) alternatively chosen, but debates still exist in its clinical efficiency. COX-2 instability through inhibiting COX-2 N-glycosylation of GS-HCl raised the possibility of NSAID sparing effect. Study was done to determine whether combination treatment of glucosamine and NSAID contributes to gastric safety through NSAID sparing effect. IEC-6 cells were stimulated with TNF-α and compared the expressions of inflammatory mediators after indomethacin alone or combination of indomethacin and GS-HCl by Western blotting and RT-PCR. C57BL/6 mice injected with type II collagen to induce arthritis were treated with indomethacin alone or combination of reduced dose of indomethacin and GS-HCl after 3 weeks. TNF-α increased the expression of COX-2, iNOS and inflammatory cytokines, but GS-HCl significantly attenuated TNF-α-induced COX-2 expression. Decreased COX-2 after GS-HCl was caused by N-glycosylation inhibition as much as tunicamycin. Combination of reduced dose of indomethacin and GS-HCl significantly reduced the expressions of ICAM-1, VCAM-1, IL-8, IL-1β, MMP-2, MMP-7, MMP-9, and MMP-11 mRNA as well as NF-κB activation better than high dose indomethacin alone. These NSAID sparing effect of GS-HCl was further proven in collagen-induced arthritis model. Combination of GS-HCl and 2.5 mg/kg indomethacin showed significant protection from gastric damages as well as efficacious anti-arthritic effect. Taken together, COX-2 N-glycosylation inhibition by GS-HCl led to indomethacin sparing effects, based on which combination of GS-HCl and reduced dose of NSAID can provide the strategy to secure stomach from NSAID-induced gastric damage as well as excellent anti-arthritic effects.