Pulmonary kinetics of 13N-ammonia in smoking subjects--a quantitative study using dynamic PET]

To evaluate the effect of smoking on nonrespiratory function in the lung, a dynamic PET with 13NH3 in the lung was performed in 18 normal volunteers without lung disease nor congestion (9 non-smokers, 4 exsmokers, 5 smokers). After intravenous bolus injection of 13NH3, twenty serial 5.5-second scans followed by six 30-second scans were performed. Regions of interests were assigned on the ventral, lateral and dorsal part of the right lung and time-activity curves were generated through 26 images. The activity curve demonstrated a biexponential clearance from the lung with fast and slow component. The retention fraction (RF), fractional size of the slow component, was calculated, and the half-times (t 1/2) of both components were also evaluated. A significant increase of RF and prolongation of t 1/2 of slow component were observed in smokers compared to non-smokers and exsmokers. However, no significant difference of RF nor t 1/2 of both components was observed between non-smokers and exsmokers. These results suggest that long term smoking may modify the pulmonary kinetics of 13NH3, but the change is reversible after cessation of smoking for one year or longer.     

The effect of donor specific blood transfusion (DST) on graft survival--intermittent coverage of cyclophosphamide

Donor specific blood transfusion (DST), given prior to living related kidney transplantation has resulted in significant improvement in graft survival. This improvement, however, has been accomplished with a high rate of adverse sensitization against the donor. In an attempt to reduce the incidence of sensitization, we have employed DST with intermittent coverage of cyclophosphamide. A comparative study was done between 2 methods of DST with or without the coverage of immunosuppressant for prospective kidney transplant recipients from living related donors. In addition, the beneficial effect of DST on graft survival was evaluated in our recent series of living related transplantation using cyclosporine A (CsA) as postoperative immunosuppression. Twenty-nine prospective kidney transplant patients received 200 ml of fresh whole blood 3 times at 2 week intervals from HLA one-haploidentical living related donors. The first 13 patients received DST alone, while the remaining 16 were given cyclophosphamide (CPM 1.5 mg/kg/day) for 3 days prior to each DST. In patients with CPM coverage, 6.3% (1 of 16) developed positive T-warm antibody against donor and 15% of patients (2 of 13) with DST alone developed it. Like-wise 19% (3 of 16) of the former and 38% (5 of 13) of the latter became positive B-warm crossmatch. The difference in sensitization rates between these 2 groups was not statistically significant. Nineteen patients receiving DST were compared to 21 non-DST patients in incidence of acute rejection, graft function and graft survival with the same immunosuppressive regimen, such as CsA, prednisolone, and mizoribine.(ABSTRACT TRUNCATED AT 250 WORDS)     

Development of new immunoradiometric assay for CA 125 antigen using two monoclonal antibodies produced by immunizing lung cancer cells

CA 125 is an antigen associated with non-mucinous epithelial ovarian cancer, which is defined by OC 125 antibody developed by immunizing ovarian cancer cells. We have produced two monoclonal antibodies, 130-22 and 145-9, by using the human lung adenocarcinoma cell line PC-9. Both 130-22 and 145-9 antibodies recognized CA 125 antigen. However, the binding sites seemed to be separate from those of OC 125. Testing by 9 immunoradiometric assays (IRMA), using different combinations of the 3 monoclonal antibodies 130-22, 145-9 and OC 125 demonstrated that the best standard curve for detecting CA 125 could be obtained by a "simultaneous sandwich" assay based on a mixture of 125I-labeled OC 125 and 130-22 or 145-9 coated beads. One-step IRMA, using 130-22 as a tracer and 145-9 as an immunoadsorbent, also showed good reproducibility and sensitivity for measuring CA 125. Antigens were detectable in the culture supernatants of PC-9 cells and 5 of 6 ovarian cancer and endometrial adenocarcinoma cells. These results indicate that one-step IRMA using 130-22 and 145-9 is useful for detecting CA 125 antigen.     

The effect of a mixture of tegafur with uracil (UFT) on hepatocarcinogenesis in rats induced by 3'-methyl-4-dimethylaminoazobenzene. I. The influence on production of alpha-fetoprotein

We studied the effect of UFT (a mixture of Tegafur and uracil at a ratio of 1:4) on hepatocarcinogenesis and alpha-fetoprotein (AFP) production induced by 3'-methyl-4-dimethylaminoazobenzene (3'-MeDAB) in rats. By feeding rats with 3'-MeDAB diet, serum AFP started to appear from week 2-3 and increased until week 5-7, then declined until week 10-11. This phenomenon of a transient appearance of serum AFP is called "primary reaction". After week 11 hepatoma started to develop accompanied with an enormous elevation of serum AFP level until animals die, generally before week 25. Male Donryu strain rats fed a diet containing 0.06% 3'-MeDAB for 10 weeks, and then fed the normal diet. UFT was given by a stomach tube once a day for five days a week. Blood was collected from the tail vein every other week and serum AFP was measured by Rocket electrophoresis technique. When the administration of UFT (10 mg or 20 mg/kg/day) was started simultaneously with feeding 3'-MeDAB diet, the primary reaction was somewhat suppressed, and after week 11 development of hepatoma and elevation of AFP were markedly inhibited. The administration of UFT of a high dose (40 mg/kg/day) caused the death of animals in 7 weeks probably because of its toxicity. When the administration of UFT (10 mg or 20 mg/kg/day) was started after finish of feeding 3'-MeDAB diet for 10 weeks, the drug was not effective. These results show that if the administration of UFT was commenced at the same time with feeding 3'-MeDAB diet, the hepatocarcinogenesis and AFP production are strongly inhibited.     

FARP2 triggers signals for Sema3A-mediated axonal repulsion

Sema3A, a prototypical semaphorin, acts as a chemorepellent or a chemoattractant for axons by activating a receptor complex comprising neuropilin-1 as the ligand-binding subunit and plexin-A1 as the signal-transducing subunit. How the signals downstream of plexin-A1 are triggered upon Sema3A stimulation, however, is unknown. Here we show that, in the presence of neuropilin-1, the FERM domain-containing guanine nucleotide exchange factor (GEF) FARP2 associates directly with plexin-A1. Sema3A binding to neuropilin-1 induces the dissociation of FARP2 from plexin-A1, resulting in activation of FARP2's Rac GEF activity, Rnd1 recruitment to plexin-A1, and downregulation of R-Ras. Simultaneously, the FERM domain of FARP2 sequesters phosphatidylinositol phosphate kinase type I isoform PIPKIgamma661 from talin, thereby inhibiting its kinase activity. These activities are required for Sema3A-mediated repulsion of outgrowing axons and suppression of neuronal adhesion. We therefore conclude that FARP2 is a key molecule involved in the response of neuronal growth cones to class-3 semaphorins.     

Extrapyramidal motor symptoms versus striatal infarction volume after focal ischemia in mongolian gerbils

Few behavioral tests are available to evaluate extrapyramidal dysfunctions after focal cerebral ischemia in rodents, although extrapyramidal motor dysfunctions are often observed clinically in patients with cerebral infarction. We evaluated the methamphetamine (MP)-induced rotation test for the detection and quantification of extrapyramidal motor dysfunction induced by striatal infarction in gerbils after focal cerebral ischemia. Mongolian gerbils (n=79) underwent the left common carotid artery occlusion (CCAO) for 10, 15, or 20 min. Spontaneous and MP-induced rotation tests were repeated postischemia, and the results compared with the extent of ischemic tissue injury. The density of dopaminergic neurons immunostained with a tyrosine hydroxylase antibody in the substantia nigra pars compacta (SNpc) also was measured. Histological examination revealed selective neuronal death of the hippocampal cornu ammonis 1 (CA1) sector in 10-min CCAO animals, infarction confined to the striatum and hippocampal neuronal death in 15-min CCAO animals, and widespread hemispheric infarction in 20-min CCAO animals. Dopaminergic neurons in the SNpc were preserved in 10- and 15-min CCAO animals but were significantly reduced in 20-min CCAO animals. In MP-induced rotation tests, 15-min CCAO animals showed biased rotation ipsilateral to the lesioned side. Biased rotation persisted 4 weeks postischemia, and the number of rotations significantly correlated with the regional infarction volume of the striatum. Twenty-minute CCAO animals showed biased rotation contralateral to the lesioned side; rotation number was not correlated with the infarction volume. Our results show that biased rotation behavior is a sensitive parameter of the extent of striatal injury after focal cerebral ischemia provided the lesion is not extended to the ipsilateral cortex. MP-induced rotation in rodents probably coordinates with the extrapyramidal motor dysfunction after striatal infarction in patients with vascular Parkinsonism.