Synthesis of 18F-FDG with FDG MicroLab system: basic studies for clinical application

We synthesized 18F-FDG by using an automated synthetic apparatus "FDG MicroLab" (GE Medical Systems) which produces 18F-FDG by a solid phase 18F-fluorination. Its quality and reproducibility were evaluated in order to assess feasibility of the apparatus for routine clinical production of 18F-FDG. For 5 consecutive 18F-FDG synthesis, target irradiation was carried out at 15 microA for 60 min. 18F-FDG was obtained in 50 min after EOB with an end-of-synthesis yield of 9.34 +/- 1.06 GBq. Radiochemical yield and radiochemical purity were 47 +/- 3% (decay corrected) and 98.0 +/- 0.5%, respectively. Other several quality control parameters tested conformed with "Standards of Compounds Labeled with Positron Nuclides" (RADIOISOTOPES, 44, 1995). Thus, the automated synthetic apparatus "FDG MicroLab" has proven to stably produce 18F-FDG with high yield and high purity. The apparatus is feasible for routine clinical production of 18F-FDG.     

Hepatic arterial infusion chemotherapy using percutaneous catheter placement with an implantable port: assessment of factors affecting patency of the hepatic artery

OBJECTIVE: To assess the factors affecting patency of the hepatic artery during hepatic arterial infusion chemotherapy (HAIC) with an implantable port system inserted percutaneously. PATIENTS AND METHODS: Ninety patients with malignant hepatic tumours were given HAIC using percutaneous catheter placement. An end-hole catheter was inserted into the hepatic artery (conventional method) in 41 patients. An end-closed and side-hole catheter was used in 49 patients, in which the catheter tip was fixed in the gastroduodenal artery and the side hole was placed in the common hepatic artery (fixed catheter-tip method). The patency of the hepatic artery was evaluated with computed tomography (CT) arteriography using the implantable port system and angiography. Then, the factors affecting hepatic arterial patency were analysed. RESULTS: Hepatic arterial occlusion was observed in 15 patients (17%). The overall patency of the hepatic artery was 86.9%, 78.4% and 51.5% at 6 months, 1 year and 2 years, respectively. The patency rate of the hepatic artery was significantly higher in patients with catheter placement using fixed catheter-tip method than those using conventional method (P = 0.01), and in patients without transcatheter arterial chemoembolization (TACE) prior to catheter placement than those with prior TACE (P = 0.01). When the variables affecting patency of the hepatic artery were studied together by multivariate analyses, the important factors were the method of catheter placement and the presence or absence of prior TACE. CONCLUSION: We consider that it is important for long-term patency of the hepatic artery during HAIC to use fixed catheter-tip method for percutaneous catheter placement instead of conventional method, and to select patients without prior TACE.     

An ultraviolet absorbing pigment causes a narrow-band violet receptor and a single-peaked green receptor in the eye of the butterfly Papilio

The distal photoreceptors in the tiered retina of Papilio exhibit different spectral sensitivities. There are at least two types of short-wavelength sensitive receptors: an ultraviolet receptor with a normal spectral shape and a violet receptor with a very narrow spectral bandwidth. Furthermore, a blue receptor, a double-peaked green receptor and a single-peaked green receptor exist. The violet receptor and single-peaked green receptor are only found in ommatidia that fluoresce under ultraviolet illumination. About 28% of the ommatidia in the ventral half of the retina exhibit the UV-induced fluorescence. The fluorescence originates from an ultraviolet-absorbing pigment, located in the most distal 70 microns of the ommatidium, that acts as an absorption filter, both for a UV visual pigment, causing the narrow spectral sensitivity of the violet receptor, and for a green visual pigment, causing a single-peaked green receptor.     

In vitro antiplatelet profile of FR171113, a novel non-peptide thrombin receptor antagonist

We have examined the potency of several adenosine receptor antagonists at adenosine A₁ and A_2A receptors using quantitative autoradiography and have compared the results with those of previous studies using the same radioligands in membrane preparations. The agonists [³H]cyclohexyladenosine and [³H]2-[p-(2-carbonylethyl)-phenylethylamino]-5′-N-ethylcarboxamido adenosine ([³H]CGS 21680) were used as radioligands for the two receptors. The results show that 1,3-dipropyl-8-cyclopentyl xanthine (DPCPX) is almost 1000-fold and 8-chloro-4-cyclohexyl-amino-1-(trifluoromethyl)[1,2,4]triazolo[4,3-a] quinoxaline (CP-68,247) about 300-fold more potent at adenosine A₁ receptors in cortex and striatum than at striatal adenosine A_2A receptors. Conversely, 5-amino-7-(2-phenylethyl)-2-(2-furyl)-pyrazolo-[4,3-e]-1,2,4-triazolo [1,5-c]pyrimidine (SCH 58261) is approximately 1000-fold and 4-(2-[7-amino-2-(2-furyl) [1,2,4]-triazolo[2,3-a][1,3,5]triazin-5-yl amino]ethyl)phenol (ZM 241,385) about 400-fold more potent at adenosine A_2A than at A₁ receptors. Caffeine and its metabolites did not show any selectivity. Other studied antagonists were non-selective or showed a modest (20- to 40-fold) adenosine A_2A receptor selectivity. Thus, only a few of the antagonists show such high selectivity that it is not offset by differences in drug distribution and levels of receptor subtype expression.     

Potential applicability of clinical hyperthermia using a Thermotron-RF8 as assessed from thermal distribution in an agar phantom containing hydroxyapatite

We have already reported the antitumour effect of hydroxyapatite (HAP) containing anticancer drugs. In this study, we found an increased temperature effect around HAP particle(s) in an agar phantom in comparison with other areas when a Thermotron-RF8 (RF generator) was used for heating. Furthermore, it was revealed that the quantity of doxorubicin hydrochloride (DOX) released from HAP containing the drug (DOX-HAP complex) was increased by raising the temperature. These results indicated that the antitumor effect of the DOX-HAP complex + hyperthermia system was greater than that of either the DOX-HAP complex or hyperthermia system alone.     

Increased levels of urinary interleukin-6 in Kawasaki disease

Kawasaki disease (KD) often presents with abnormal urinary findings, such as aseptic pyuria, mild proteinuria and microscopic haematuria. In this study, we measured urinary interleukin-6 (IL-6) by a sensitive sandwich ELISA assay using mouse monoclonal antibodies against recombinant IL-6 to elucidate the role of IL-6 in the pathogenesis of renal lesions in KD. Serum IL-6 levels were increased in acute KD as well as in febrile controls. Importantly, urinary IL-6 levels were consistently elevated in patients with acute KD, but much lower in febrile controls. Urinary IL-6 levels returned steadily to normal during the convalescent phase. In addition to IL-6, urinary levels ofN-acetyl--d-glucosaminidase (NAG) and ₂-microglobulin (₂-mg) were also elevated during the acute phase of this disease. Eosinophils and macrophages were identifiable in urinary sediments from these patients. The increased levels of urinary IL-6 in combination with increased NAG and ₂-mg seemed to suggest the presence of certain renal parenchymal lesions with cellular infiltration during the acute phase of the disease. IL-6 may serve as clinically useful parameter for the detection and monitoring of the renal involvement in KD.     

Restoration of hearing with an auditory brainstem implant in a patient with neurofibromatosis type 2--case report

A 25-year-old male with neurofibromatosis type 2 had hearing restored with an auditory brainstem implant (ABI) after removal of an acoustic schwannoma. The ABI allows the patient to discern many different environment sounds and is a significant adjunct to lip-reading, enabling conversation with people who have clear pronunciation without the necessity for writing.     

An experimental study of the effects of nerve root retraction on the posterior ramus

STUDY DESIGN: The histologic and ultrastructural changes in the posterior ramus after posterior lumbar surgery were studied in rabbits. OBJECTIVE: To investigate the structural changes in the posterior ramus after posterior lumbar surgery that may cause injury to the posterior ramus after the procedure. SUMMARY OF BACKGROUND DATA: Investigators in previous studies have pointed out that low back discomfort after lumbar discectomy relates to neurogenic changes and/or myogenic changes of paravertebral muscle. However, no previous study has demonstrated the effects of excessive nerve root retraction on spinal posterior rami. METHODS: Eighteen male Japanese White rabbits were used. The posterior ramus arising from the S1 nerve root was examined after exposure of the lamina only, fenestration, or retraction of the S1 nerve root, with light microscopy and transmission electron microscopy at 2, 4, and 6 weeks after the procedure. Results were compared with a those in control specimens that did not undergo the procedure. RESULTS: In the exposed group, no distinct difference was found compared with the control specimen. In the fenestration group, especially at 6 weeks, some attenuation and splitting of myelin sheaths was observed. In the retraction group, the structural alteration was most severe. Even at 2 weeks, fragmentation of many myelin sheaths was detected. Examination of specimens by electron microscopy indicated phagocytosis of myelinated fibers at 4 and 6 weeks. CONCLUSIONS: Findings showed that posterior lumbar procedures, including retraction of paravertebral muscle, fenestration of the lamina, and retraction of the nerve root affect the posterior ramus. Excessive retraction of the nerve root has an especially disastrous effect on the posterior ramus. Such a violent maneuver within the spinal canal must be avoided.     

Significance of percutaneous cardiopulmonary bypass support for volume reduction surgery with severe hypercapnia

In patients with reduced respiratory function, lung resection is associated with high risk because separate ventilation is generally needed for safe management. For patients with end-stage emphysema, intraoperative respiratory management is important and particularly difficult because neither incomplete oxygenation nor selective ventilation can be performed, so the operation may be interrupted. In this study, we assess the effectiveness of the percutaneous cardiopulmonary support (PCPS) system for lung volume reduction surgery in patients with severe hypercapnia (arterial carbon dioxide tension >50 mm Hg) and discuss the significance of PCPS for patients who are beyond the standard criteria for lung volume reduction surgery (LVRS). We studied 3 patients with severe hypercapnia due to emphysema who underwent volume reduction surgery. One patient was previously treated surgically for contralateral pneumothorax. All patients had a severe smoking history and were suspected to have fragile lungs. During the operation. PCPS provided sufficient support flow. Intraoperative management using PCPS was easy, and no severe complications were observed. One patient exhibited severe hemodynamic deterioration on postoperative Day 15. Other patients' PaCO2 improved postoperatively. One had a calcification of a femoral artery, but there was no trouble inserting a cannula. Bilateral or unilateral volume reduction surgery was performed under PCPS in patients with end-stage emphysema. We conclude that PCPS is an adjunct to LVRS, useful for intraoperative management of some patients with severe hypercapnea, and the LVRS indications can be extended.