Fixation of a modified covered esophageal stent: its clinical usefulness for preventing stent migration

BACKGROUND AND STUDY AIMS: Membrane-covered self-expandable metal stents are effective in preventing tumor ingrowth and stent obstruction in patients with inoperable esophageal cancer, but migration of stents continues to be a major problem. We therefore constructed a modified covered self-expandable esophageal metal stent capable of being fixed using a silk thread. The stent was studied prospectively to define its palliative characteristics and whether it is effective in preventing migration. PATIENTS AND METHODS: Modified covered self-expandable metal stents were placed in 17 patients with malignant gastric cardiac cancer involving the esophagogastric junction, 41 patients with esophageal cancer, and three patients with tracheoesophageal fistulas. Clinical and radiographic follow-up examinations were carried out at regular intervals. RESULTS: Placement of the stent was successful in all patients, with good symptomatic relief and no serious stent-related complications such as esophageal perforation or hemorrhage. Acute stent placement problems, such as incomplete expansion or acute angulation of the stent, were noted in four patients. However, during a mean follow-up period of 7.5 months (range 1 to 17 months), there was no stent migration. CONCLUSIONS: Modified covered self-expandable esophageal metal stents of this type would be very effective in preventing stent migration, especially in patients with malignant gastric cardiac cancer extending to the lower esophagus, those with short-segment esophageal cancer, and those with tracheoesophageal fistulas.     

Sugar‐Derived Poly(β‐thioester)s as a Biomedical Scaffold

The monomer isosorbide diacrylate (iSDA) and commercially available dithiols allowed access to a range of biosourced, degradable polymers. Altering the dithiol identity significantly affected the glass transition T_gs of the polymer products; however, polymers did not exhibit T_gs above room temperature. Incorporating the comonomer N,N′‐methylene bisacrylamide provided mechanical reinforcement through hydrogen bonding, resulting in soft, pliable materials. Differential scannin calorimetry (DSC) and variable‐temperature fourier‐transform infrared (FTIR) spectroscopy indicated that increases in mechanical integrity resulted from hydrogen bonding. Dynamic mechanical analysis (DMA) revealed materials that exhibited suitable moduli and service windows at body temperature. Biological evaluation demonstrated favorable cytotoxicity and cell attachment, rendering these materials potential candidates as novel scaffold materials for tissue growth.     

Chronic Daily Headache and Medication Overuse Headache in First-Visit Headache Patients in Korea: A Multicenter Clinic-Based Study

MethodsEleven neurologists enrolled first-visit patients with complaints of headaches into outpatient clinics for further assessment. Headache disorders were classified according to the International Classification of Headache Disorder (third edition beta version) by each investigator.ResultsPrimary CDH was present in 248 (15.2%) of the 1,627 included patients, comprising CM (143, 8.8%), chronic tension-type headache (CTTH) (98, 6%), and definite new daily persistent headache (NDPH) (7, 0.4%). MOH was associated with headache in 81 patients (5%). The association with MOH was stronger among CM patients (34.5%) than patients with CTTH (13.3%) or NDPH (14.3%) (p=0.001). The frequency of CDH did not differ between secondary and tertiary referral hospitals.ConclusionsThe frequencies of CDH and MOH diagnoses were 15.2% and 5%, respectively in first-visit headache patients presented at secondary or tertiary referral hospitals in Korea. CM was the most common subtype of CDH and was most frequently associated with MOH.     

Brief Episodes of Newly Developed Intraoperative Atrial Fibrillation Predicts Worse Outcomes in Adult Liver Transplantation

Background

Although patients undergoing liver transplantation (LT) are frequently exposed to predisposing factors of atrial fibrillation (AF) such as autonomic imbalance, surgical stress, and elevated catecholamine levels, the occurrence of intraoperative AF (IOAF) has not been fully examined in LT candidates.

Effects of corticopuncture (CP) and low-level laser therapy (LLLT) on the rate of tooth movement and root resorption in rats using micro-CT evaluation

The aim of this study was to compare the rate of tooth displacement, quantity of root resorption, and alveolar bone changes in five groups: corticopuncture (CP), low-level laser therapy (LLLT), CP combined with LLLT (CP?+?LLLT), control (C), and negative control (NC). A total of 60 half-maxilla from 30 male Wistar rats (10 weeks old) were divided randomly into five groups: three (CP, LLLT, and CP?+?LLLT) test groups with different stimulation for accelerated-tooth-movement (ATM), one control (C) group, and one negative control (NC) group with no tooth movement. Nickel-titanium coil springs with 50 g of force were tied from the upper left and right first molars to micro-implants placed behind the maxillary incisors. For the CP and CP?+?LLLT groups, two perforations in the palate and one mesially to the molars were performed. For the LLLT and CP?+?LLLT groups, GaAlAs diode laser was applied every other day for 14 days (810 nm, 100 mW, 15 s). The tooth displacements were measured directly from the rat’s mouth and indirectly from microcomputer (micro-CT) tomographic images. Bone responses at the tension and compression sites and root resorption were analyzed from micro-CT images. The resulting alveolar bone responses were evaluated by measuring bone mineral density (BMD), bone volume fraction (BV/TV), and trabecular thickness (TbTh). Root resorption crater volumes were measured on both compression and tension sides of mesial and distal buccal roots. The tooth displacement in the CP?+?LLLT group was the greatest when measured clinically, followed by the CP, LLLT, and control groups (C and NC), respectively (p?<0.05). The tooth movements measured from micro-CT images showed statistically higher displacement in the CP and CP?+?LLLT groups compared to the LLLT and control groups. The BMD, BV/TV, and TbTh values were lower at the compression side and higher at the tension side for all three test groups compared to the control group. The root resorption crater volume of the distal buccal root was higher in the control group, followed by CP, LLLT, and CP?+?LLLT, mostly at the compression site. Combining corticopuncture and low-level laser therapy (CP?+?LLLT) produced more tooth displacement and less root resorption at the compression side. The combined technique also promoted higher alveolar bone formation at the tension side.     

Kinetics of intravenous melphalan.

We have studied the disposition and elimination of melphalan after intravenous administration in 9 patients with cancer. High-pressure liquid chromatography and 14C-melphalan were used to assay drug concentration in plasma and urine. Composite plasma t1/2alpha was 7.7 +/- 3.3 and t1/2beta was 108 +/- 20.8 min for 8 of the patients. The mean 24-hr urinary excretion of melphalan was 13.0 +/- 5.4% of the administered dose. In 2 patients, 80% to 100% of the measured 14C counts in plasma and urine samples at each study interval, up to 24 hr after drug administration, could be accounted for by the sum of parent compound, monohydroxy and dihydroxy products, and methanol nonextractable radioactivity (i.e., protein-bound activity). These data and evidence of rapid disappearance from plasma at 37 degrees in vitro suggest that spontaneous degradation, and not enzymatic metabolism, is the major determinant of the t1/2 of melphalan in vivo.