Changes in the leukocyte distribution and surface expression of adhesion molecules induced by hypothalamic stimulation in the cat

Emotions and the neuroendocrine system are known to affect leukocyte distribution. However, there have so far been few reports on the relationship between hypothalamically induced emotional behavior and the endocrine-immune response. We previously reported changes in the leukocyte distribution and adhesion molecules induced by anteromedial hypothalamus stimulation (AH stimulation), which elicits restlessness behaviors in the cat. In this study, we examined ventromedial hypothalamus stimulation (VMH stimulation), which elicits threat behaviors. In addition, the endocrine responses after VMH stimulation were evaluated. VMH stimulation as well as AH stimulation induced elevations of plasma cortisol and epinephrine levels and granulocytosis and lymphopenia. In contrast, VMH stimulation induced only an elevation of plasma norepinephrine and elicited an opposite pattern of CD62L expression on the leukocyte subpopulations. The different endocrine-immunological reactions between VMH stimulation and AH stimulation were thus associated with different types of behavioral responses.     

Detection of hypervascular hepatocellular carcinoma by dynamic magnetic resonance imaging with double-echo chemical shift in-phase and opposed-phase gradient echo technique: comparison with dynamic helical computed tomography imaging with double arterial phase

PURPOSE: The technique of double-echo chemical shift gradient echo magnetic resonance imaging (MRI) with the fast low-angle shot (double-echo FLASH) sequence provides in-phase and opposed-phase images in a single breath hold. The purpose of this study was to evaluate the efficacy of dynamic MRI with double-echo FLASH imaging for the detection of hypervascular hepatocellular carcinoma by comparing it with dynamic helical computed tomography (CT) imaging with double arterial phase. MATERIALS AND METHODS: Twenty-nine patients with 67 hypervascular hepatocellular carcinoma nodules who underwent both dynamic MRI with double-echo FLASH imaging (repetition time/echo time/flip angle: 160/3.6, 7.0/80 degrees ) and dynamic helical CT imaging with double arterial phase were enrolled in the study. For dynamic MRI, precontrast, arterial, portal venous, and equilibrium phase images were obtained before and approximately 19, 60, and 120 seconds, respectively, after intravenous injection of 0.1 mmol/kg of gadopentetate dimeglumine at a rate of 2 ml/s. For dynamic CT imaging, quadraphase images, including early arterial, late arterial, portal venous, and equilibrium phases, were obtained serially approximately 20, 30, 70, and 180 seconds, respectively, after intravenous administration of 2 ml/kg of 300 mgI/ml of nonionic contrast medium at a rate of 5 ml/s. Three masked observers independently interpreted images obtained with each technique in random order, separately and without patient identifiers. Sensitivity and positive predictive values as well as the area below the alternative-free response receiver operating characteristic curve (Az) for each imaging technique were calculated and compared statistically. RESULTS: Mean sensitivity and positive predictive values of MRI for hypervascular hepatocellular carcinoma were 48% and 94%, respectively, and those of CT imaging were 47% and 91%, respectively. In 11 (38%) of the 29 patients, at least one observer judged dynamic MRI to be superior, whereas in 5 patients (17%), dynamic CT was judged to be superior. There was no significant difference in the sensitivity and positive predictive values between these techniques (p > 0.05). There was no significant difference either in mean Az values between CT (0.55) and MRI (0.57) (p = 0.61). CONCLUSION: Dynamic MRI with double-echo FLASH imaging can detect hypervascular hepatocellular carcinoma as well as dynamic helical CT imaging with double arterial phase.     

High dose rate endovascular brachytherapy in aorto-iliac lesion for the prevention of restenosis

This study examined the applicability of endovascular brachytherapy to larger del arteries such as the abdominal aorta and iliac artery. Endovascular brachytherapy using an Ir-192 HDR source was administered 11 times to nine patients who had undergone percutaneous transluminal angioplasty (PTA) between 1995 and 1999. The follow-up lasted 13 to 55 months after treatment (median, 24 months). Eight of the 11 lesions have been controlled so far. Although one case developed thrombus inside the stent five months later, recanalization was achieved by means of retreatment. One patient who underwent low-dose irradiation (6 Gy) without stent implantation showed restenosis five months after treatment. We used a centering catheter that did not block the blood stream for exact centering of the radiation source in larger vessels such as the abdominal aorta. Although endovascular brachytherapy is a promising and safe procedure, careful follow-up is needed to detect untoward reactions such as thrombosis.     

New Hepatocellular Carcinoma Cell Line SUHC-1 Established from a Patient with Hepatitis C Virus RNA in Serum

A new human hepatocellular carcinoma cell (HCC) line, designated SUHC-1, was derived from a Japanese patient with hepatocellular carcinoma having antibody to hepatitis C virus (HCV) and HCV-RNA in his serum, and established in tissue culture. This cell line exhibited typical epithelial cell morphology in culture as observed by phase-contrast and electron microscopy. The SUHC-1 cells produced albumin and α₂-macroglobulin. Chromosomal analysis showed several rearrangements at short and long arms of chromosome 1, 17 and 20 (1p–, 1q–, i(1q), i(17q) and 20q +) with a modal number of 91. HCV-RNA was not detected in the supernatant of SUHC-1 cells by nested polymerase chain reaction assay or in the SUHC-1 cells by the in situ hybridization method. We concluded that complete HCV does not exist in the SUHC-1 cell line. The SUHC-1 cell line is the first line of HCC to have been derived from a patient with persistent HCV infection, and may provide a suitable model for studies of hepatocarcinogenesis related to HCV.     

Angiotensin blockade inhibits osteopontin expression in non-infarcted myocardium after myocardial infarction

Osteopontin has been reported to have an important role in cardiac fibrosis. However, little is known about the effects of angiotensin-converting enzyme inhibitor (ACEI) and angiotensin type 1 receptor blockers (ARB) on osteopontin expression in infarcted myocardium. The purpose of this study was to elucidate the effects of an ACEI (perindpril) and an ARB (candesartan cilexitil) on cardiac function as assessed by Doppler echocardiography and cardiac osteopontin expression associated with cardiac remodeling in myocardial infarcted rats. ACEI or ARB was administered after myocardial infarction (MI). At 4 weeks after MI, cardiac function, and mRNAs in non-infarcted myocardium were analyzed. ACEI and ARB equally prevented left ventricular dilatation, reduction of ejection fraction, and the increase in E/A wave velocity ratio and the rate of E wave deceleration by MI. ACEI and ARB significantly suppressed increased mRNA expression of atrial natriuretic peptide, brain natriuretic peptide, osteopontin, and collagen I and III in the non-infarcted ventricle at 4 weeks. Immunohistochemically stained osteopontin was increased in interstitial fibrosis of non-infarcted myocardium. Both ACEI and ARB significantly prevented cardiac fibrosis and osteopontin expression. In conclusion, angiotensin blockade inhibits osteopontin expression in non-infarcted myocardium and prevents cardiac remodeling after MI.     

Preparing oral dosage form of ketamine in the hospital for simplicity and patient compliance--preparations using agar

Ketamine has been widely used in the operation as intravenous and intramuscular injections, since ketamine has dissociative anesthetic properties. When it is given in sub-anesthetic dose, ketamine is known to have an analgesic effect. The analgesic effect is observed for patients with neuropathic pain when administrated not only by injection but also orally. In Japan, since ketamine is not commercially available except injection forms, patients have to take it as solution of injections for the oral medication. Since the solution of injections has extremely bitter taste, patients intensely desire the development of preparations without the bitterness. In the present study, we prepared oral gel dosage forms of ketamine using agar. It is simple to prepare this dosage form, and most pharmacists can prepare it easily in many hospitals. This gel dosage form met content uniformity requirements and the shape of that was maintained intact during the dissolution test (for 10 hours). The release rate was reduced by additions of additives such as sugar and a flavor in the gel. The reason for the reduction in release could be the suppression of ketamine diffusion depended on the micro-viscosity of solution in the gel. The ketamine contents and the release profile of the gel preparations were unchanged at the room temperature for 12-week storage. The gel preparations in this study would be useful for the oral medication of ketamine, since it is easy for patients to carry them when they go out and the intensely bitter taste could be improved by the addition of a flavor.     

Cobalt chloride induces neurite outgrowth in rat pheochromocytoma PC-12 cells through regulation of endothelin-2/vasoactive intestinal contractor

We investigated whether endothelin-2/vasoactive intestinal contractor (ET-2/VIC) gene expression, upregulated by hypoxia in cancer cells, was associated with differentiation in neuronal cells. RT-PCR analysis, morphological observations, and immunostaining revealed that CoCl2, a hypoxic mimetic agent, at 200 microM increased expression of the ET-2/VIC gene, decreased expression of the ET-1 gene, and induced neurite outgrowth in PC-12 rat pheochromocytoma cells. These effects induced by 200 microM CoCl2 were completely inhibited by the antioxidant N-acetyl cysteine at 20 mM. In addition, CoCl2 increased the level of intracellular reactive oxygen species (ROS) at an early stage. Furthermore, interleukin (IL)-6 gene expression was upregulated upon the differentiation induced by CoCl2. These results suggest that expression of ET-2/VIC and ET-1 mediated by ROS may be associated with neuronal differentiation through the regulation of IL-6. When the cells were treated with 500 microM CoCl2 for 24 hr, however, ET-2/VIC gene expression disappeared, IL-6 gene expression was downregulated, and necrosis was subsequently induced in the PC-12 cells.     

T staging of gastric cancer: role of multi-detector row CT

PURPOSE: To evaluate retrospectively the accuracy of multi-detector row computed tomography (CT) in the assessment of serosal invasion in patients with gastric cancer. MATERIALS AND METHODS: The Ethics Committee does not require approval or informed consent for retrospective studies. Forty-one consecutive patients (24 men, 17 women; mean age, 68 years) with gastric cancer were included in this study. All patients were given 600 mL of tap water to drink and were positioned prone or supine on the scanning table. The detector row configuration included four detector rows, a section thickness of 1.25 mm, a pitch of 6, and a reconstruction interval of 0.63 mm. Transverse and multiplanar reconstruction images were simultaneously evaluated by two independent observers to assess the depth of tumor invasion in the gastric wall (ie, T stage). T staging at multi-detector row CT was compared with T staging at histologic evaluation (reference standard), which was performed by means of surgical or histologic examination of the resected specimen. We also calculated the sensitivity, specificity, and accuracy of multi-detector row CT for each observer in the assessment of serosal invasion. RESULTS: Analysis of interobserver agreement showed substantial or almost perfect agreement (nonweighted kappa value of 0.78 and weighted kappa value of 0.85). Correct assessment of gastric wall invasion was 80% and 85% for observers 1 and 2, respectively. The sensitivity, specificity, and accuracy of multi-detector row CT in the assessment of serosal invasion were 90%, 95%, and 93%, respectively, for observer 1 and 80%, 97%, and 93%, respectively, for observer 2. Overstaging occurred in six patients, and understaging occurred in five patients. All understaged tumors were scirrhous subtype gastric cancer. CONCLUSION: Multi-detector row CT scanning of patients with gastric cancer gave 93% accuracy in the assessment of serosal invasion in patients with gastric cancer.     

Prospective respiratory-triggered multidetector row CT (MDCT) for abdominal examinations: initial experience with a prototype

PURPOSE: To develop a prototype for prospective respiratory-triggered multidetector row computed tomography (MDCT) for abdominal examinations and to assess its feasibility. MATERIALS AND METHODS: The prototype consisted of the following components: an MDCT unit, personal computer (PC), and a respiratory motion detector in the form of a wearable belt with sensors to measure differences in pressure caused by breathing excursions. The registered signals were processed by the PC. The abdominal MDCT images of 10 healthy volunteers were obtained with an incremental axial technique in the expiration phase during normal breathing. Multiplanar reformations (MPR) were then performed. On the basis of the precision of these reconstructions, two radiologists then assessed the accuracy and applicability of the system. RESULTS: Coronal and sagittal MPR images from these prospective respiratory-gated examinations were found to be accurate. In particular, the continuity of borders and surfaces of scanned organs proved the exactness of the previously acquired respiration-correlated axial source images. CONCLUSION: This prototype is feasible to perform prospective respiratory-triggered abdominal MDCT examinations during normal respiration without breathhold. This system may be useful for patients with reduced compliance in holding their breath.     

MR appearances of radiofrequency thermal ablation region: histopathologic correlation with dog liver models and an autopsy case

RATIONALE AND OBJECTIVES: The purpose of this study was to evaluate the utility of magnetic resonance (MR) imaging for indicating the extent of true tissue necrosis of the liver after radiofrequency (RF) ablation in comparison with histopathologic findings in dog models and an autopsy case. MATERIALS AND METHODS: RF ablation of the liver parenchyma was performed on three dogs under general anesthesia. MR appearances of the RF-ablated regions on T1-weighted fast-low angle shot (FLASH; repetition time/echo time [TR/TE]/flip angle: 120/3.8/70),T2-weighted turbo spin echo (3000/80/echo train = 25) and contrast-enhanced T1-weighted images were compared with histopathologic findings. An autopsy case with hepatocellular carcinoma was also enrolled in this study. RESULTS: All ablated regions showed three zones on T1-weighted FLASH images: a central zone with low intensity, a broad hyperintense middle zone, and a surrounding hypointense band. The central and middle zones corresponded to the degrees of coagulation necrosis observed during histopathologic examination, whereas no viable cells were seen in these zones during the microscopic examination using nicotinamide adenine dinucleotide diaphorase stain. The surrounding hypointense band corresponded to sinusoidal congestion in the acute phase and to fibrotic change in the subacute phase. CONCLUSION: MR imaging using the FLASH sequence can accurately determine the extent of the necrotic area after RF ablation.