Buccal mucosal ulcer healing effect of rhEGF/Eudispert hv hydrogel

We have studied the effect of rhEGF on the buccal mucosal ulcer healing. rhEGF was rapidly degraded upon incubation with the hamster buccal mucosal homogenates; The degradation of rhEGF was significantly inhibited by sodium lauryl sulfate (SLS). Eudispert hv hydrogel and Polycarbophil 974P hydrogel were prepared for rhEGF delivery and their mucoadhesiveness was measured by the Instron method. The mucoadhesive force of Eudispert hv was significantly greater than that of Polycarbophil 974P. Moreover, rhEGF in Eudispert hv hydrogel remained stable for about 2 months. To evaluate the ulcer healing effect of rhEGF, the buccal mucosal ulcer was induced in golden hamsters using acetic acid. At 24 h after administration of rhEGF/Eudispert hv hydrogel, the ulcerous area was decreased compared with rhEGF solution and, as a result, the curative ratio was 36.8 +/- 5.68%. By the addition of SLS (0.5%) to Eudispert hv hydrogel, the curative ratio increased 1.5 times. The mechanism of the action was probably due to a combination of protection of the drug against proteases present in mucosa and prolongation of the release of rhEGF from the formulation at the site of action.     

Formaldehyde-induced gene expression in F344 rat nasal respiratory epithelium

Formaldehyde (FA), an occupational and environmental toxicant used extensively in the manufacturing of many household and personal use products, is known to induce squamous cell carcinomas in the nasal turbinates of rats and mice and squamous metaplasia in monkey noses. Tissue responses to FA include a dose dependent epithelial degeneration, respiratory cell hypertrophy, and squamous metaplasia. The primary target for FA-induced toxicity in both rodents and monkeys is the respiratory nasal epithelium. FA increases nasal epithelial cell proliferation and DNA-protein crosslinks (DPX) that are associated with subsequent nasal cancer development. To address the acute effects of FA exposure that might contribute to known pathological changes, cDNA gene expression analysis was used. Two groups of male F344 rats received either 40 ul of distilled water or FA (400 mM) instilled into each nostril. Twenty-four hours following treatment, nasal epithelium was recovered from which total RNA was used to generate cDNA probes. Significance analysis of microarrays (SAM) hybridization data using Clontech Rat Atlas 1.2 arrays revealed that 24 of the 1185 genes queried were significantly up-regulated and 22 genes were significantly downregulated. Results for ten of the differentially expressed genes were confirmed by quantitative real time RT PCR. The identified genes with FA-induced change in expression belong to the functional gene categories xenobiotic metabolism, cell cycle, apoptosis, and DNA repair. These data suggest that multiple pathways are dysregulated by FA exposure, including those involved in DNA synthesis/repair and regulation of cell proliferation. Differential gene expression profiles may provide clues that could be used to define mechanisms involved in FA-induced nasal cancer.     

Acute cholecystitis at T2-weighted and manganese-enhanced T1-weighted MR cholangiography: preliminary study

Twelve patients with symptoms of acute cholecystitis underwent heavily T2-weighted and mangafodipir trisodium-enhanced T1-weighted magnetic resonance (MR) cholangiography and cholescintigraphy before they underwent cholecystectomy. On T2-weighted MR cholangiographic images, morphologic evidence of outflow obstruction of the gallbladder was definitive in seven patients, equivocal in one, and absent in four. In all 12 patients, biliary dynamics depicted at manganese-enhanced T1-weighted MR cholangiography agreed completely with those depicted at hepatobiliary scintigraphy. T2-weighted MR cholangiography combined with manganese-enhanced T1-weighted MR cholangiography provides not only morphologic information but also functional information about the biliary system.     

Inflammatory pseudotumor of the carotid artery: radiologic findings

The radiologic appearance of inflammatory pseudotumor in the two cases presented was a fusiform mass surrounding the carotid bifurcation. The masses showed an avascular mass with focal narrowing of the carotid bifurcation on carotid arteriography, a homogeneous hypoechoic mass on ultrasound, less enhancement on contrast-enhanced computed tomography, and relatively intense enhancement on magnetic resonance imaging.     

Transcaval Transjugular Intrahepatic Portosystemic Shunt: Preliminary Clinical Results

Objective

To determine the feasibility of transcaval transjugular intrahepatic portosystemic shunt (TIPS) creation in patients with unusual anatomy between the hepatic veins and portal bifurcation, and inaccessible or inadequate hepatic veins.

Materials and Methods

Transcaval TIPS, performed in six patients, was indicated by active variceal bleeding (n=2), recurrent variceal bleeding (n=2), intractable ascites (n=1), and as a bridge to liver transplantation (n=1). The main reasons for transcaval rather than classic TIPS were the presence of an unusually acute angle between the hepatic veins and the level of the portal bifurcation (n=3), hepatic venous occlusion (n=2), and inadequate small hepatic veins (n=1).

Results

Technical and functional success was achieved in all patients. The entry site into liver parenchyma from the inferior vena cava was within 2 cm of the atriocaval junction. Procedure-related complications included the death of one patient due to hemoperitoneum despite the absence of contrast media spillage at tractography, and another suffered reversible hepatic encephalopathy.

Conclusion

In patients with unusual anatomy between the hepatic veins and portal bifurcation, and inaccessible or inadequate hepatic veins, transcaval TIPS creation is feasible.     

Balloon-Occluded Retrograde Transvenous Obliteration for Gastric Variceal Bleeding: Its Feasibility Compared with Transjugular Intrahepatic Portosystemic Shunt

Objective

To assess the feasibility of balloon-occluded retrograde transvenous obliteration (BRTO) in active gastric variceal bleeding, and to compare the findings with those of transjugular intrahepatic portosystemic shunt (TIPS).

Materials and Methods

Twenty-one patients with active gastric variceal bleeding due to liver cirrhosis were referred for radiological intervention. In 15 patients, contrast-enhanced CT scans demonstrated gastrorenal shunt, and the remaining six (Group 1) underwent TIPS. Seven of the 15 with gastrorenal shunt (Group 2) were also treated with TIPS, and the other eight (Group 3) underwent BRTO. All patients were followed up for 6 to 21 (mean, 14.4) months. For statistical inter-group comparison of immediate hemostasis, rebleeding and encephalopathy, Fisher''s exact test was used. Changes in the Child-Pugh score before and after each procedure in each group were statistically analyzed by means of Wilcoxon''s signed rank test.

Results

One patient in Group 1 died of sepsis, acute respiratory distress syndrome, and persistent bleeding three days after TIPS, while the remaining 20 survived the procedure with immediate hemostasis. Hepatic encephalopathy developed in four patients (one in Group 1, three in Group 2, and none in Group 3); one, in Group 2, died while in an hepatic coma 19 months after TIPS. Rebleeding occurred in one patient, also in Group 2. Except for transient fever in two Group-3 patients, no procedure-related complication occurred. In terms of immediate hemostasis, rebleeding and encephalopathy, there were no statistically significant differences between the groups (p > 0.05). In Group 3, the Child-Pugh score showed a significant decrease after the procedure (p = 0.02).

Conclusion

BRTO can effectively control active gastric variceal bleeding, and because of immediate hemostasis, the absence of rebleeding, and improved liver function, is a good alternative to TIPS in patients in whom such bleeding, accompanied by gastrorenal shunt, occurs.     

Vascular responses in normal canine carotid arteries: comparison between various self-expanding stents of the same unconstrained size

RATIONALE AND OBJECTIVES: To compare long-term vascular responses upon the insertion of various self-expandable stents, all the same unconstrained size, in canine carotid artery models. MATERIALS AND METHODS: Twenty-two stents (5 SMARTs, 5 Wallstents, 6 Niti-Ss, 6 Niti-Ds) of the same unconstrained size (6 mm in diameter, 20 mm in length) were endovascularly placed in canine common carotid arteries. The luminal changes were measured on three occasions, on prestenting, immediate poststenting, and angiograms taken before specimens were killed. After en-bloc harvest of the stented carotid arteries at 6 months, the intraluminal surface was evaluated by gross observation and scanning electron microscopy (SEM). Neointimal thickness was measured at several points both over the wire and between the wires. RESULTS: Niti-D was excluded from analysis because of high rate of poststenting occlusion. SMART stent showed the greatest expansibility with average initial luminal gain ( < 0.05) of 21.2% (Niti-S: 16.5%, Wallstent: 12.9%). At 6 months follow-up, the dilated arterial lumen had returned almost to the prestenting caliber without any significant differences among the stent types ( > 0.05). The thickness of neointimal coverage was more prominent with SMART stent (354 microm over the wire and 258 microm between the wires) than Niti-S (228 microm and 83 microm) or Wallstent (187 microm and 78 microm). CONCLUSION: Stent types with its higher initial luminal gain appeared to be associated with thicker neointimal formation at 6 months. The acute expanding force of a self-expanding stent may be the key to the cause of neointimal hyperplasia. Regardless of the inserted stent type, the variations in neointimal response were offset by luminal gains of varying degree, thus preserving the arterial patency almost to the prestenting size.