Olmesartan is an angiotensin II receptor blocker with an inhibitory effect on angiotensin-converting enzyme.

Angiotensin II receptor blockers (ARBs) are widely used for the treatment of hypertension. It is believed that treatment with an ARB increases the level of plasma angiotensin II (Ang II) because of a lack of negative feedback on renin activity. However, Ichikawa (Hypertens Res 2001; 24: 641-646) reported that long-term treatment of hypertensive patients with olmesartan resulted in a reduction in plasma Ang II level, though the mechanism was not determined. It has been reported that angiotensin 1-7 (Ang-(1-7)) potentiates the effect of bradykinin and acts as an angiotensin-converting enzyme (ACE) inhibitor. It is known that ACE2, which was discovered as a novel ACE-related carboxypeptidase in 2000, hydrolyzes Ang I to Ang-(1-9) and also Ang II to Ang-(1-7). It has recently been reported that olmesartan increases plasma Ang-(1-7) through an increase in ACE2 expression in rats with myocardial infarction. We hypothesized that over-expression of ACE2 may be related to a reduction in Ang II level and the cardioprotective effect of olmesartan. Administration of 0.5 mg/kg/day of olmesartan for 4 weeks to 12-week-old stroke-prone spontaneously hypertensive rats (SHRSP) significantly reduced blood pressure and left ventricular weight compared to those in SHRSP given a vehicle. Co-administration of olmesartan and (D-Ala7)-Ang-(1-7), a selective Ang-(1-7) antagonist, partially inhibited the effect of olmesartan on blood pressure and left ventricular weight. Interestingly, co-administration of (D-Ala7)-Ang-(1-7) with olmesartan significantly increased the plasma Ang II level (453.2+/-113.8 pg/ml) compared to olmesartan alone (144.9+/-27.0 pg/ml, p<0.05). Moreover, olmesartan significantly increased the cardiac ACE2 expression level compared to that in Wistar Kyoto rats and SHRSP treated with a vehicle. Olmesartan significantly improved cardiovascular remodeling and cardiac nitrite/ nitrate content, but co-administration of olmesartan and (D-Ala7)-Ang-(1-7) partially reversed this anti-remodeling effect and the increase in nitrite/nitrate. These findings suggest that olmesartan may exhibit an ACE inhibitory action in addition to an Ang II receptor blocking action, prevent an increase in Ang II level, and protect cardiovascular remodeling through an increase in cardiac nitric oxide production and endogenous Ang-(1-7) via over-expression of ACE2.     

Endoscopic anterior cruciate ligament reconstruction using a computer-assisted fluoroscopic navigation system

Background During anterior cruciate ligament (ACL) reconstruction, placement of the reconstructed ligament affects the clinical results. To accomplish accurate and reproducible placement of the tibial bone tunnel, we employed a fluoroscopic navigation system for endoscopic ACL reconstruction. In this study, preciseness of the tibial tunnel placement was evaluated, and the advantages and disadvantages of this navigation system for endoscopic ACL reconstruction are discussed. Methods Altogether, 16 knees of 16 patients who had undergone ACL reconstruction using this system (navi group) were evaluated regarding the positioning of the tibial tunnel against Blumensaat's line using X-p and the route of the graft by magnetic resonance imaging (MRI). Another 16 knees of 16 patients who underwent endoscopic ACL reconstruction without the navigation system were the controls (control group). Results At the 1-year follow-up, maximally extended lateral knee X-p revealed that the anterior edge of the tibial tunnel and Blumensaat's line were almost aligned and that roof impingement was avoided; the T2-weighted MR images showed that the graft was placed close to and parallel to the intercondylar roof in all the knees of the navi group. The ratio of the distance between Blumensaat's line and the anterior edge of the tibial tunnel at the level of the tibial plateau to the anteroposterior width in fully extended true lateral radiographs was 2.7% ± 3.4% in the navi group and 8.4% ± 7.4% in the control group. Conclusions The computer-assisted fluoroscopic navigation system improves accuracy and decreases dispersion of the tibial tunnel placement against Blumensaat's line in single-bundle ACL reconstruction. This innovative device renders the reconstruction procedure more reliable, eliminating the problem of skeletal variation among patients. However, the function of this navigation system for femoral tunnel placement is insufficient at present. Further refinement of the system is necessary, and the method of application requires improvement.     

IMPROVED BALLOON‐TIPPED TRANS‐ANAL ILEUS TUBE

Background: For management of bowel obstruction due to colorectal cancer, endoscopic trans‐anal decompression technique has been first reported by Lelcuk et al. in 1986 using balloon dilatation technique. Since then, various types of trans‐anal decompression tubes have been clinically used for patients suffering from left side obstructing colorectal cancer as an emergent decompressing device. At present, two types of trans‐anal ileus tube (trans‐anal decompression tube) have been available for clinical use, but they have two main problems that are late colon perforations caused by the tip of the tube and tube obstruction by stool. Methods: Analysis on three late colon perforations experienced with the use of conventional devices drew possible improvements to make a trans‐anal ileus tube less harmful. To overcome the pitfalls inherent to conventional tubes, the author has developed an improved trans‐anal ileus tube with a balloon installed at the very end of the tube (‘balloon‐tipped type’) made of silicone, measuring 1200 or 1700 mm in total length and 22 Fr in outer diameter. It has been used for 12 cases with obstructing colorectal cancer etc. and its outcomes were compared with those obtained by the use of conventional trans‐anal ileus tube. Results: No late perforations have been encountered, but tube obstruction did occur in one of 12 cases. Conclusion: The new trans‐anal ileus tube with a balloon installed at the tip of ileus tube is considered to be safer and especially effective in preventing late colon perforation and tube obstruction.     

A case of pulmonary artery bypass surgery for a patient with isolated Takayasu pulmonary arteritis and a review of the literature.

A 45-year-old female was presented with progressive dyspnea and bilateral leg edema. Pulmonary angiography revealed total occlusion of the right pulmonary artery and significant stenosis of the left pulmonary artery. The inferior lobar artery as well as the segmental arteries were well patent. No pathology was detected elsewhere at the aorta and its branches. The diagnosis of chronic pulmonary arterial occlusion by isolated Takayasu arteritis was made because of the characteristic pattern of angiographic findings and the presence of unusual shunt formation from the coronary artery to the peripheral portion of the pulmonary artery, as well as a characteristic presentation of HLA typing in blood analysis, which strongly suggested the diagnosis of Takayasu arteritis. To restore the pulmonary blood flow, we employed reconstructive surgery by means of bypass procedure, using PTFE graft. Postoperatively there was marked improvement in cardiopulmonary function and the quality of life of the patient. The graft was proved to be patent at long-term follow-up study. An extremely rare case of chronic occlusive pulmonary arteritis, which was surgically treated by means of bypass procedure, is reported herein, and a brief review of previous reports on this subject was attempted.     

Pancreatic metastasis of malignant melanoma diagnosed by EUS-guided fine needle aspiration (EUS-FNA)]

Pancreatic metastasis of malignant melanoma is rarely diagnosed while the patient is alive. We report a case of metastatic melanoma of the pancreas in a 35-year-old woman presenting with a solid mass of the pancreas. Her past medical history included a radical hysterectomy 2 years previously for malignant melanoma of the vagina. Twelve months later, lung metastasis was also resected. EUS-guided fine needle aspiration (EUS-FNA) identified that the pancreatic tumor was histologically and immunohistochemically identical to the surgical specimen of her lung neoplasm. Imaging studies including US, CT, and MRI have limited value to distinguish the tumors from primary ductal adenocarcinoma. EUS-FNA can provide tissue diagnosis from pancreatic masses, specifically when other modalities have failed.     

A female case with Down syndrome and non-neurogenic neurogenic bladder

Although the prevalence of a learned voiding dysfunction and non-neurogenic neurogenic bladder (NNB), which is one type of dysfunctional elimination syndrome, is considered to be relatively rare, the association of NNB with Down syndrome (DS) has been elucidated in male patients. We herein describe the occurrence of NNB in an adult female with DS. The diagnosis was confirmed after completely ruling out any neurological or anatomical anomalies that could be related to a lower urinary tract dysfunction. She had renal dysfunction and multiple obstructive uropathies for which clean intermittent catheterization was successfully introduced.     

New hepatic vein reconstruction in left liver graft.

The incidence of hepatic venous stenosis is higher in partial liver transplantation. New methods for hepatic venous reconstruction in left liver transplantation, which secure wide anastomosis, were devised and are reported here. In the graft, the right side of the middle hepatic vein or the left side of the left hepatic vein was cut longitudinally and a rectangular-shaped vein patch was attached for venoplasty. In the recipient, after the left and middle hepatic veins were joined, the right side of the middle hepatic vein was cut toward the closed right hepatic vein, making a horizontal cavotomy for anastomosis. Of 92 patients who underwent conventional hepatic vein reconstruction, 3 were complicated by hepatic venous stenosis (median follow-up 43 months). By contrast, there were no hepatic vein complications in the 20 patients who underwent the new technique (7 months). The current method appears to be technically feasible for outflow reconstruction in left liver graft transplantation.     

Effects of dominant and nondominant eyes in binocular rivalry.

PURPOSE: To investigate the relation between sighting and sensory eye dominance and attempt to quantitatively examine eye dominance using a balance technique based on binocular rivalry. METHODS: The durations of exclusive visibility of the dominant and nondominant eye target in binocular rivalry were measured in 14 subjects. The dominant eye was determined by using the hole-in-card test (sighting dominance). In study 1, contrast of the target in one eye was fixed at 100% and contrast of the target in the other eye was varied from 100% to 80% to 60% to 40% to 20%, when using rectangular gratings of 1, 2, and 4 cycles per degree (cpd) at 2 degrees, 4 degrees , and 8 degrees in size. In study 2, contrast of the target in the nondominant eye was fixed at 100% and contrast of the target in the dominant eye was varied from 100% to 80% to 60% to 40% to 20%, when using a rectangular grating of 2 cpd at 4 degrees in size. RESULTS: In study 1, the total duration of exclusive visibilities of the dominant eye target; that is, the target seen by the eye that had sighting dominance was longer compared with that of the nondominant eye target. When using rectangular gratings of 4 cpd, mean total duration of exclusive visibility of the dominant eye target was statistically longer than that of the nondominant eye target (p < 0.05). In study 2, reversals (in which duration of exclusive visibility of the nondominant eye becomes longer than the dominant eye when the contrast of the dominant eye target is decreased) were observed for all contrasts except for 100%. CONCLUSIONS: The dominant sighting eye identified by the hole-in-card test coincided with the dominant eye as determined by binocular rivalry. The contrast at which reversal occurs indicates the balance point of dominance and seems to be a useful quantitative indicator of eye dominance to clinical applications.     

Modifying Effects of Various Chemicals on Preneoplastic and Neoplastic Lesion Development in a Wide-spectrum Organ Carcinogenesis Model Using F344 Rats

Modifying potentials of various chemicals on tumor development were investigated in a wide-spectrum organ carcinogenesis model using male F344/DuCrj rats. The animals were treated with N-nitroso-diethylamine (100 mg/kg body weight, ip, single injection at the commencement of the study), N-methyl-N-nitrosourea (20 mg/kg body weight, ip, 4 times during weeks 1 and 2) and N-bis(2-hydroxypropyl)nitrosamine (0.1% in drinking water, during weeks 3 and 4) for multi-organ initiation and then were given one of 14 test chemicals including 6 hepatocarcinogens, 7 non-hepatocarcinogens and 1 non-carcinogen, or basal diet for 16 weeks. All rats were killed at the end of week 20, and the major organs were carefully examined for preneoplastic and neoplastic lesions. Immunohistochemical demonstration of glutathione S -transferase-positivc foci was also used for quantitative assessment of liver preneoplastic lesion development. Modifying effects were shown for 11 out of 14 test agents in the liver, forestomach, glandular stomach, lung, urinary bladder or thyroid, 7 of them targeting more than two organs. This was the first demonstration to our knowledge that cloflbrate possesses enhancing potential for urinary bladder carcinogenesis and an inhibiting effect on thyroid carcinogenesis. Caprolactam showed no effect in any organ, in agreement with its established inactivity. The results indicated that the system could be reliably applied as a medium-term multiple organ bioassay for assessment of the modification potential of test agents in unknown target sites.