Two Cases of Cystic Fibrosis in Japanese Children: Studies on the Essential Fatty Acid and Prostaglandin Metabolism

We describe the fatty acid (FA) and prostaglandin (PG) metabolism in two Japanese cases of cystic fibrosis (CF) with or without pancreatic insufficiency (PI). The diagnosis of CF was based on the elevated sweat chloride concentration by pilocarpine iontophoresis. A 1-month-old boy (case 1) showed poor weight gain, steatorrhea and scaly dermatitis, but no respiratory symptoms were noted. He had decreased levels of serum linoleate and arachido-nate, and increased palmitoleate and oleate levels, indicating essential fatty acid (EFA) deficiency. Supplementation of fat-emulsion improved his skin lesions and the altered FA pattern within a few months, associated with the definite reduction of the urinary PC F_za levels. Until two years of age, he has been free from respiratory symptoms. A 12-year-old girl (case 2) had had recurrent respiratory tract infections due to Pseudomonas ueruginoso and Staphylococcus aureus for several years, and her pancreatic functions were preserved. The FA patterns of her serum lipid were almost within the normal range. These results indicate that 1) the altered FA composition appeared to be a secondary consequence of PI commonly complicating CF and 2) the correction of the altered FA and PC metabolism might have a beneficial effect on the respiratory function of CF patients with EFA deficiency.     

Effects of cerebral protective agents in experimental cerebral ischemia. Relationship between the degree of ischemia and EEG

We have previously demonstrated that the preischemic administration of perfluorochemicals (PFC) in combination with 20% mannitol, vitamin E and dexamethasone is effective in protecting the brain from cerebral ischemia. This experimental study was designed to evaluate the effect and limitation of the post-ischemic administration of those 4 agents on cerebral ischemia. We used "Canine model of complete ischemic brain regulated with a perfusion method." Using this model we were able to control the amount of blood flow to the left cerebral hemisphere by using an infusion pump. Infusion blood volume was reduced to 30%, 40% or 50% of the normal state, then the combined treatment was started 1,2,3,4,5 or 6 hours after the onset of ischemia in each ischemic group. By monitoring the EEG for 8 hours of ischemic period, we were able to evaluate the effect of the drugs on cerebral ischemia. In untreated groups, electrical activity deteriorated gradually. In the 30% ischemia group, the EEG became isoelectric within 1 hour following ischemia. In half of the 40% ischemia group, the EEG became isoelectric but in the other half low voltage slow wave were seen to last for 6-8 hours. In the 50% group, the EEG deteriorated gradually but did not disappear within 8 hours. The effectiveness of the treatment was judged by the degree of the recovery of electrical activity. The effectiveness of the treatment appeared to depend on the severity and the duration of ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)     

Protective effect of phenytoin and its enhanced action by combined administration of mannitol and vitamin E in cerebral ischemia

Phenytoin is well known as the anticonvulsant agent and also said to protect the brain against ischemic damage. The purpose of the present experiment is to study the therapeutic effect of phenytoin on cerebral ischemia and confirm whether the effectiveness of phenytoin could be enhanced by combination of free radical scavengers such as mannitol and vitamin E. In this experiment, twenty-five dogs were subjected to ischemia, using the "canine model of complete ischemic brain regulated with a perfusion method" in which it is possible to control the degree of blood flow to a cerebral hemisphere via a perfusion pump at will. Five animals served as untreated control, fifteen received treatment with phenytoin (7 mg/kg in five dogs, 10 mg/kg in five dogs and 30 mg/kg in five dogs) and five treated with 10 mg/kg phenytoin, 2 g/kg of mannitol and 30 mg/kg of vitamin E. These drugs were administered intravenously 20 minutes prior to the production of ischemia, when cerebral blood flow was reduced to one-tenth its normal volume. After one hour, cerebral blood flow was restored and the recovery of electrical activity of the brain and the degree of brain swelling were observed for three hours. With regard to the recovery of EEG, no recovery of EEG was seen subsequent to recirculation except one dog in the control group. Whereas in the group treated with phenytoin, gradual emergence of slow wave ws observed soon after recirculation. The higher the administered dosage is, the better the degree of recovery of EEG was seen. Thus, the dose-related recovery of EEG was observed within the dose ranges tested.(ABSTRACT TRUNCATED AT 250 WORDS)     

Interinstitutional variations in planning for stereotactic body radiation therapy for lung cancer

PURPOSE: The aim of this study was to assess interinstitutional variations in planning for stereotactic body radiation therapy (SBRT) for lung cancer before the start of the Japan Clinical Oncology Group (JCOG) 0403 trial. METHODS AND MATERIALS: Eleven institutions created virtual plans for four cases of solitary lung cancer. The created plans should satisfy the target definitions and the dose constraints for the JCOG 0403 protocol. RESULTS: FOCUS/XiO (CMS) was used in six institutions, Eclipse (Varian) in 3, Cadplan (Varian) in one, and Pinnacle3 (Philips/ADAC) in one. Dose calculation algorithms of Clarkson with effective path length correction and superposition were used in FOCUS/XiO; pencil beam convolution with Batho power law correction was used in Eclipse and Cadplan; and collapsed cone convolution superposition was used in Pinnacle3. For the target volumes, the overall coefficient of variation was 16.6%, and the interinstitutional variations were not significant. For maximal dose, minimal dose, D95, and the homogeneity index of the planning target volume, the interinstitutional variations were significant. The dose calculation algorithm was a significant factor in these variations. No violation of the dose constraints for the protocol was observed. CONCLUSION: There can be notable interinstitutional variations in planning for SBRT, including both interobserver variations in the estimate of target volumes as well as dose calculation effects related to the use of different dose calculation algorithms.     

Phase I study of cisplatin analogue nedaplatin, paclitaxel, and thoracic radiotherapy for unresectable stage III non-small cell lung cancer

BACKGROUND: The standard treatment of unresectable stage III non-small cell lung cancer is concurrent chemoradiotherapy in patients in good general condition, but where the optimal chemotherapeutic regimen has not been determined. METHODS: Patients with unresectable stage III non-small cell lung cancer received nedaplatin (80 mg/m2) and paclitaxel on day 1 every 4 weeks for 3-4 cycles and concurrent thoracic radiotherapy (60 Gy/30 fractions for 6 weeks) starting on day 1. The dose of paclitaxel was escalated from 120 mg/m2 in level 1, 135 mg/m2 in level 2 to 150 mg/m2 in level 3. RESULTS: A total of 18 patients (14 males and 4 females, with a median age of 62.5 years) were evaluated in this study. Full cycles of chemotherapy were administered in 83% of patients in level 1, and in 50% of patients in levels 2 and 3. No more than 50% of patients developed grade 4 neutropenia. Transient grade 3 esophagitis and infection were noted in one patient, and unacceptable pneumonitis was noted in three (17%) patients, two of whom died of the toxicity. Dose-limiting toxicity (DLT), evaluated in 15 patients, noted in one of the six patients in level 1, three of the six patients in level 2 and one of the three patients in level 3. One DLT at level 2 developed later as radiation pneumonitis. Thus, the maximum tolerated dose was determined to be level 1. The overall response rate (95% confidence interval) was 67% (41-87%) with 12 partial responses. CONCLUSION: The doses of paclitaxel and nedaplatin could not be escalated as a result of severe pulmonary toxicity.     

Retinoschisin is a peripheral membrane protein with affinity for anionic phospholipids and affected by divalent cations

PURPOSE: Retinoschisin (RS) is a retina-specific, secreted protein implicated in X-linked juvenile retinoschisis and essential for the structural and functional integrity of the retina. This biochemical characterization and ultrastructural localization of RS in intact murine retina was performed to further understanding of the molecular basis of its function. METHODS: Subcellular fractions and fractions enriched in photoreceptor inner and outer segments were prepared from mouse retina by differential or density gradient ultracentrifugation. Immunoblot analysis was used to assess the expression of RS in various subcellular compartments and its fractionation into soluble phase on treatment of retinal cell membranes with several solubilizing reagents. RS-lipid interactions were evaluated by a protein-lipid overlay assay that used wild-type and mutant forms of RS discoidin domain glutathione S-transferase (GST) fusion proteins. The subcellular localization of RS in mouse retina was visualized by pre-embedding immunogold electron microscopy. Ultrastructure was evaluated by transmission electron microscopy. RESULTS: RS was intimately associated with cell membranes of the retina. It was found to cluster on the outer leaflet of the plasma membrane of the photoreceptor inner segments, which synthesize and secrete it. It was released from the membrane at high pH, which is characteristic of a peripheral membrane protein. It was extracted from the membrane by the nonionic detergent NP-40, together with glycerophospholipids. Protein-lipid overlay assays indicated a preferential interaction between RS and anioic phospholipids. Extraction of RS from the membrane was inhibited by divalent cations. Photoreceptor inner segment morphology was markedly affected in RS(-)(/y) mice, which failed to express RS protein. CONCLUSIONS: RS in intact retina is a peripheral membrane protein. Although distributed over the two membrane faces, RS is associated primarily with the outer leaflet of the inner segment plasma membrane through anionic phospholipids and divalent cations. RS's localization in photoreceptors and its biochemical properties suggest a functional role locally, at the site of secretion and membrane adhesion, in maintaining the photoreceptor inner segment stability and architecture.     

Photodynamic therapy induces caspase-dependent apoptosis in rat CNV model

PURPOSE: To investigate the mechanism of cell death in laser-induced choroidal neovascularization (CNV) after photodynamic therapy (PDT). METHODS: PDT was performed in Brown-Norway rats using laser light at a wavelength of 689 nm, irradiance of 600 mW/cm(2), and fluence of 25 J/cm(2) after intravenous injection of verteporfin at the doses of 3, 6, and 12 mg/m(2). Apoptotic cells in CNV were detected by TUNEL assay at 1, 3, 6, 15, 24, and 48 hours after PDT. Caspase activation at 1, 3, 6, 15, and 24 hours after PDT was determined by immunohistochemistry (IHC) with a cleaved caspase-3 or -9 antibody. Akt activity was determined by Western blot and IHC with a phosphorylated-Akt (pAkt) antibody. To investigate the roles of Akt in PDT-induced apoptosis, insulin-like growth factor (IGF)-1, an Akt activator, with or without wortmannin, an inhibitor of PI3K-Akt pathway, was injected into the vitreous before PDT. RESULTS: The number of TUNEL-positive cells in CNV increased at 3 hours after PDT and peaked at 6 hours, showing a dose dependence of verteporfin. Caspase activation was detected in TUNEL-positive cells. Dephosphorylation of Akt in CNV occurred within 1 hour. IGF-1 significantly activated Akt and suppressed the number of TUNEL-positive cells in CNV, and the effects of IGF-1 were diminished by wortmannin. CONCLUSIONS: PDT induced caspase-dependent apoptosis in CNV. These results suggest that PDT leads to dephosphorylation of Akt and subsequent activation of the caspase-dependent pathway. Understanding the intracellular signaling mechanisms of apoptosis in PDT may lead to more selective and effective treatment of CNV secondary to age-related macular degeneration.