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Injectable polymers (IPs) exhibiting in situ hydrogel formation have attracted attention as vascular embolization and postoperative adhesion prevention materials. While utilizing hydrogels for such purposes, it is essential to ensure that they have appropriate and controllable tissue adhesion property, as it is crucial for them to not detach from their deposited location in the blood vessel or abdominal cavity. Additionally, it is important to maintain gel state in vivo for the desired period at such locations, where large amounts of body fluid exist. We had previously reported on a biodegradable IP system exhibiting temperature-responsive gelation and subsequent covalent cross-link formation. We had utilized triblock copolymers of aliphatic polyester and poly(ethylene glycol) (tri-PCGs) and its derivative containing acrylate group at the termini (tri-PCG-Acryl), exhibiting a longer and more controllable duration time of the gel state. In this study, the introduction of aldehyde groups by the addition of aldehyde-modified Pluronic (PL-CHO) was performed for conferring controllable and appropriate tissue adhesive properties on these IP systems. The IP systems containing PL-CHO, which were not covalently incorporated into the hydrogel network, exhibited tissue adhesive properties through Schiff base formation. The adhesion strength could be controlled by the amount of PL-CHO added. The IP system showed good vascular embolization performance and pressure resistance in the blood vessels. The IP hydrogel remained at the administration site in the abdominal space for 2 days and displayed effective adhesion prevention performance. STATEMENT OF SIGNIFICANCE: Injectable polymers (IPs), which exhibit in situ hydrogel formation, are expected to be utilized as vascular embolization and postoperative adhesion prevention materials. The tissue adhesion properties of hydrogels are important for such applications. We succeeded in conferring tissue adhesion properties onto a previously reported IP system by mixing it with Pluronic modified with aldehyde groups (PL-CHO). The aldehyde groups allowed for the formation of Schiff bases at the tissue surfaces. The tissue adhesion property could be conveniently controlled by altering the amount of PL-CHO. We revealed that the in vitro embolization properties of IPs in blood vessels could be substantially improved by mixing with PL-CHO. The IP system containing PL-CHO also exhibited good in vivo performance for postoperative adhesion prevention.

AIM: Prostaglandins (PGs) and leukotrienes (LTs) are major factors involved in the defense of the gastric mucosa against ulcer formation. However, little is still known about the gastromucosa-protecting action of proton pump inhibitors (PPIs) and histamine H2 receptor antagonists (H2 blockers) in patients with gastric ulcer. We therefore examined the effectiveness of a PPI in protecting the gastric mucosa.METHODS: We compared the PGE2 and LTB4 levels and the expression levels of cyclooxygenase (COX)-1 and COX-2 mRNA in the gastric mucosa in gastric ulcer patients between the group treated for 8 weeks with a PPI, rabeprazole (PPI group; n=5), and the group treated for 8 weeks with an H2 blocker, ranitidine (H2 blocker group; n=6), as well as in nonulcer subjects (control group; n=5).RESULTS: The mucosal levels of PGE2 and COX-2 mRNA expression were significantly lower in the ulcer patients than those in the nonulcer patients, whereas the LTB4 level was significantly higher in the ulcer patients than that in the nonulcer patients, and it was also significantly lower in the ulcerated mucosa than that in the nonulcerated mucosa. The PPI group had a significantly increased PGE2 and decreased LTB4 levels in comparison to the H2 blocker group during the ulcer-healing stage. The COX-1 mRNA expression showed no difference among the PPI and H2 blocker groups or between before and after the treatment. However, the COX-2 mRNA expression increased in the PPI group more than that in the H2 blocker group during the ulcer-healing stage.CONCLUSION: These findings demonstrated the significant gastric-mucosa-protecting effect of PPI by increasing the PGE2 production and reducing the LTB4 production. J. Med. Invest. 54: 83-90, February, 2007

A 42-year-old male with visceral obesity and a fatty liver presented with hepatopathy accompanied by jaundice and was diagnosed to have early syphilis based on the results of standard serologic tests and clinical findings. Both the subjective and objective findings including hepatopathy were rapidly alleviated by anti-syphilitic therapy. Severe hepatopathy accompanied by jaundice used to be considered a rare complication. However, due to contemporary unhealthy lifestyle patterns characterized by hypernutrition and a lack of exercise the occurrence of fatty liver is now dramatically increasing. Our findings suggest that the occurrence of fatty liver can exacerbate the damage to the hepatic parenchyma due to a Treponema pallidum infection.

A 71-year-old male was admitted for abdominal fullness. The condition rapidly deteriorated in a short period (3 weeks), and the patient died. Autopsy revealed a protruding lesion measuring about 3 cm with erosion measuring 5 mm in diameter immediately below the esophago-gastric conjugation site, suggesting primary cardial undifferentiated adenocarcinoma. In the primary focus, changes on the mucosal surface were almost normal However, below the mucosa, infiltration of cancer cells was observed in an approximately 3 cm area along the gastric wall. Simultaneously, the site of infiltration was markedly increased in deep areas. Extraserous infiltration was observed. The morphology was special, and resembled an octopus pot, a trap used to catch octopuses in Japan, with a narrow top and a broad base. In our patient, metastatic lesions were detected in multiple organs, including the stomach.

Neoplastic natural killer (NK) cells overexpress Fas ligand (FasL), which may cause damage of Fas-bearing tissues. We report a patient with NK cell leukaemia who developed liver injury after pharyngitis. The NK leukaemic cells expressed functional FasL. In addition to soluble FasL, serum levels of interleukin-6 and interferon-γ were increased dramatically when liver injury was aggravated. Moreover, hepatocytes expressed Fas and apoptotic hepatocytes were detected in the portal areas. These findings are consistent with the notion that inflammatory cytokines enhance the sensitivity to FasL and trigger apoptosis of hepatocytes in NK cell malignancies.

A 33-year-old man with a 4-year history of Crohn's disease presented with marked ascites and an abdominal tumor. Two M-protein peaks, immunoglobulin (Ig) G-κ and IgA-κ, were detected in the serum. Neoplastic lymphoplasmacytic cells were infiltrated in the bone marrow and ascites. Histological examination of the abdominal tumor showed marked proliferation of lymphoplasmacytic cells that were positive for either IgG or IgA. Moreover, DNA sequences of the expressed IgG and IgA genes were different in the complementarity-determining region 3. These results suggest that chronic inflammation in Crohn's disease contributes to the simultaneous development of biclonal lymphoplasmacytic immunocytoma of the small intestine.(Internal Medicine 38: 500-503, 1999)

Hepatic portal venous gas (HPVG) was detected by CT in a 64-year-old woman who suddenly complained of lower abdominal pain. However, the abdominal symptoms disappeared rapidly, and lower gastrointestinal endoscopy indicated only terminal ileitis. Conservative treatment alone was performed, and HPVG completely disappeared approximately 18 hours later. The use of CT proved to be useful for following the course of HPVG.

Intestinal Behcet's disease in a 38-year-old woman was diagnosed because of the history of recurrent oral aphthous ulcers, erythema nodosum-like eruptions, genital ulcer, and endoscopic findings of esophageal and ileocolonic punched-out ulcers with colonic longitudinal ulcers. Esophageal lesions and colonic longitudinal ulcers are rarely seen in intestinal Behcet's disease. The ulcers of esophagus and ileocolon healed with 3 wk of treatment with prednisolone and mesalazine without any adverse effect. Mesalazine may decrease the total dose of prednisolone required to treat the disease.

A 51-year-old Japanese male with chief complaints of slightly high fever and epigastralgia was hospitalized at our facility. The inflammatory response was enhanced, and liver dysfunction was observed. Abdominal ultrasonography demonstrated a hyperechoic lesion occupying the left portal vein, and abdominal plain CT indicated a low density of the lesion with a clear boundary, measuring about 3 cm × 2 cm, between the porta hepatis and segment IV of the liver. Contrast CT showed no enhancement in the arterial and portal phases, but a reduction in the density inside the tumor in the equilibration phase was noted. MRI showed hypointensity by T1-weighted imaging and hyperintensity by T2-weighted imaging. Angiography demonstrated an obstruction of the left portal vein and superior mesenteric vein, and endoscopic retrograde cholangiography revealed a constriction in the left intrahepatic bile duct. Since the possibility of intrahepatic cholangiocarcinoma could not be excluded, extended left hepatectomy combined with caudate lobectomy was performed. The tumor, measuring 31 mm × 21 mm × 20 mm, was pathohistologically diagnosed as an extrahepatic portal obstruction. Extrahepatic portal obstruction is an important disease that is sometimes difficult to rule out oncologic origin. J. Med. Invest. 52: 203-207, August, 2005

Inhalation of organic solvents has long been known to damage various nervous systems, including cerebellum, brainstem, and pyramidal tract. However, little is known about the damage of the dopaminergic system. We report two patients with occupational long-term solvent exposure who developed postural instability without other features of parkinsonism. The concentration of HVA in CSF was decreased and the retropulsion was dramatically improved after the administration of levodopa. These findings indicate that the nigrostriatal dopaminergic neurons were disturbed by chronic solvent exposure, resulting in the loss of postural reflexes.