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51.
Summary The purpose of this phase I study was to evaluate the toxicity and biological activity of autologous blood-derived macrophages activated ex-vivo with recombinant human interferon (rhuIFN) [monokine-activated killer (MAK) cells] and administered intravenously to 11 lung cancer patients once a week for 6 consecutive weeks. Peripheral blood monocytes were collected by leukapheresis and then purified by counterflow elutriation. The MAK cells were generated by culturing the purified monocytes in Teflon bags for 7 days and adding rhuIFN to the cultured cells for the last 18 h. These MAK cells expressed differentiation-associated surface antigen MAX1, and were cytotoxic in vitro against tumour cell line U937. The MAK cells were infused at dose levels from 1 × 107 to 5 × 108 on an intrapatient dose-escalating schedule. No severe adverse side-effects occurred. Toxicity was mild to moderate [primarly fever (75%) and chills (32%)], non-dose-dependent, and non-cumulative. No consistent change in haemostatic function, or liver or renal function was observed. Dose-limiting toxicity was not reached at 5 × 108 cells (optimal dose reproduced for each patient). The maximum tolerated dose was not determined. The immunomodulatory activity of i.v. infused MAK cells was demonstrated both in vivo by significant increases in granulocyte count and neopterin level in the patients' peripheral blood postinfusion and in vitro by secretory products (IL-1. TNF, neopterin, and thromboplastin-like substance) in the culture supernatants. The in vivo traffic patterns of autologous MAK cells labelled ex-vivo with111In oxine were studied in 7 patients. Gamma imaging showed an immediate but transient lung uptake (<24 h), and a progressive uptake of radioactivity in the liver and spleen was seen from 6 h to 72 h post-infusion. Our results indicate that the preparation of high numbers of autologous, blood-derived MAK cells is a feasible procedure, and their transfusion is safe for patients. This immunotherapeutic approach seems to be encouraging from the point of view of establishing an adjuvant therapeutic modality in cancer patients with minimal residual disease.This work was supported in part by a grant 6911 from the Association pour la Recherche contre le Cancer (ARC), grants from the Ligue Nationale contre le cancer and the Ligues Regionales (Bas-Rhin, Haut-Rhin) contre le cancer, and contract 891013 from the Institut National pour la Santé et la Recherche Médicale (INSERM), France  相似文献   
52.
The cystine-rich antifreeze polypeptides (AFP) from sea raven were fractionated by reverse-phase high performance liquid chromatography into several components, with SR2 (Mr 17,000) as the major AFP. Sea raven AFP cDNA clones were isolated from a liver cDNA library using a synthetic oligonucleotide, and the identity of one of the clones, C2-1, was confirmed by hybridization selection and cell-free translation. C2-1 encodes a pre-AFP of 195 amino acids with no evidence of any profragments. Comparison of the deduced amino acid sequence with partial peptide sequences from SR2 showed substitutions in at least four amino acid positions, suggesting that C2-1 cDNA codes for a minor component. Both the primary and the predicted secondary structures of sea raven AFP are completely different from those of other fish AFP. This further confirms that sea raven AFP belongs to a different class of antifreezes. The high frequency of reverse turns and the presence of paired hydrophilic amino acids in these structures are striking features of the protein and may contribute to their antifreeze action.  相似文献   
53.
Little is known of the selectivity of the blood-brain barrier at birth. Hexoses are transported through the barrier by a facilitating mechanism. To study the capacity of this mechanism to distinguish between analogs of D-glucose, we compared the transport of fluorodeoxyglucose, deoxyglucose, glucose, methylglucose, mannose, galactose, mannitol, and iodoantipyrine across the cerebral capillary endothelium in newborn Wistar rats. Cerebral blood flow, glucose consumption, and the blood-brain permeabilities of the hexoses were 25-50% of the adult values but the ratios between the permeabilities of the individual hexoses were similar to the ratios observed in adult rats. The mannitol clearance into brain was considerably higher than in adult rats (about 10-fold), indicating a higher endothelial permeability to small polar nonelectrolytes. The brain water content was higher in newborn than in adult rats and was associated with a higher steady-state distribution of labeled methylglucose between brain and blood. Hexose concentrations were determined relative to whole blood because the apparent erythrocyte membrane permeability to glucose was as high as in humans and thus considerably higher than in adult rats. The half-saturation concentration of glucose transport across the blood-brain barrier was considerably higher than in adult rats, about three-fold, suggesting that net blood-brain glucose transfer is less sensitive to blood glucose fluctuation in newborn than in adult rats.  相似文献   
54.
Serum antifreeze polypeptides (AFP) from Newfoundland ocean pout have been resolved by ion exchange chromatography and reverse phase high performance liquid chromatography into at least 12 components. The protein sequences of three of the AFP were determined using a combination of protein Edman degradation and cDNA sequencing. The AFP precursor protein encodes for a preprotein of 87 amino acids with no obvious prosequences. Two of the AFP (SP1-A and SP1-C) were separate gene products with minor amino acid sequence differences. The protein structure of SP1-C precursor is MKSVILTGLLFVLLCVDHMTASQSVVAT QLIPINTALTPAMMEGKVTNPIGIPFAEMSQIVGKQVNTPVAKGQTLMPNMVKTYVAGK. The third AFP (SP1-B) is a post-translation modification product of SP1-C. These experiments indicate that the ocean pout AFP are a multigene family with protein structure different from any other known polypeptide antifreezes.  相似文献   
55.
The differential response of white clover ( Trifolium repens L. cv. Regal Ladino) and berseem clover ( Trifolium alexandrinum L. cv. Mississippi ecotype) was investigated by treating greenhouse cultured plants with 4-(2,4-dichlorophenoxy)butyric acid (2,4-DB). Berseem clover plants were significantly injured by a treatment concentration of 0.6 kg ha-1 of 2,4-DB, whereas white clover plants were not injured by treatment levels below 2.4 kg ha-1. The metabolism of 2,4-DB in cell suspension cultures of white clover and berseem clover was investigated using [ring-14C]-2,4-DB and non-labeled 2,4-DB. White clover cell cultures metabolized ca 4-fold more 2,4-DB than berseem cultures over a 44-h treatment period. The decrease in berseem cell population was 4-fold greater than the decrease in white clover cell population in response to the 8 μ M 2,4-DB treatment. The herbicide and its [ring-14C]-labeled metabolites were isolated from treated cells and medium after 44 h by partition and thin-layer chromatography. White clover cells metabolized 90% of the [14C]-2,4-DB and berseem clover cells metabolized 22% of the herbicide. The major portion of the radiolabel was in the glycoside fractions from extracts of both species. The differential response of Trifolium species to 2,4-DB is implied to be due to the differential rate of 2,4-DB metabolism to a glycoside by the clover plants.  相似文献   
56.
We have previously demonstrated that at embryonic Day (E) 8, some cells of the chick ciliary ganglion (CG) contain the catecholaminergic (CA) enzyme tyrosine hydroxylase (TH), but not phenylethanolamine-N-methyltransferase (PNMT); and that in culture essentially all cells express both enzymes. In the present study, we sought to determine, first, whether the expression of adrenergic traits in the CG in vivo is transient or permanent in the CG. To do so, CGs were removed from E5 to postnatal Day 5, fixed, and processed for the immunocytochemical localization of the CA enzymes: TH, L-amino acid decarboxylase (AADC), and PNMT. At all stages examined, some CG neurons expressed TH immunoreactivity (TH-IR) and all contained AADC-IR. However, none stained with PNMT antibodies, indicating that these cells stably express some, but not all, of the CA enzymes. Second, we examined whether CG neurons in culture expressed other CA markers. CG neurons did not contain detectable levels of TH enzyme activity nor did they transport and store exogenously supplied monoamines. These results indicate that some but not all traits necessary for adrenergic function are present in CG neurons in vitro. Third, we sought to establish whether CA expression in CG neurons is affected by modification in culture conditions. Cultures of CG neurons continued to express TH-IR even when grown in the presence of either 50% HCM or 20 mM KCl for 5 days. Finally, the expression of the cholinergic enzyme, choline acetyltransferase (CAT) was assessed in CG cultures by biochemical assay. CAT activity increased five-fold between 5 and 17 days in vitro, irrespective of the presence of TH-IR in 100% of the CG neurons of sister cultures. These data suggest that at least a subpopulation of CG neurons express both TH and CAT in culture. We conclude that the postmitotic neurons of the CG are able to express some but not all of the traits characteristic of a CA phenotype while maintaining cholinergic expression. These findings suggest that (1) the appearance of the full complement of adrenergic properties is not coordinated and may be regulated by different environmental cues and (2) parasympathetic neurons can express both adrenergic and cholinergic traits simultaneously.  相似文献   
57.
The population energetics of a temporary and a permanent pond population of Musculium partumeium in Southwest Ohio were studied. In the permanent pond (surface area = 396 m2, maximum depth = 0.7 m) the population was bivoltine and iteroparous whereas in the temporary pond (surface area = 1042 m2, maximum depth = 0.9 m) the population was usually univoltine and semelparous.Growth and biomass were assessed as total organic carbon and total nitrogen to provide estimates of productivity and seasonal changes in C:N for each generation. Productivity (non-respired assimilation = growth + reproduction; N-R.A. = G + R) was 6939 mgC·m–2·a–1 (3858 and 3353 mgC·m–2·a–1 for each generation) and 1661 mgC·m–2·a–1 for the permanent and temporary pond populations respectively. The average standing crop biomass (B) was 606.8 mgC·m–2 (357.5 and 249.3 mgC·m–2 for each generation) and 231.9 mgC·m–2 with overall productivity: biomass ratios of 11.4 and 7.2 for the permanent pond and temporary pond populations respectively.Respiration rates were converted to carbon equivalents (respired assimilation = R.A.) and used to evaluate the components of total assimilation (T.A. = R.A. + N-R.A.) and the efficiency of partitioning this energy to N-R.A. for G and R. When expressed as a percentage, the production efficiencies (100 × N-R.A.:T.A.) were 50.4 and 62%, and the reproductive efficiencies (100 × R:N-R.A.) were 26.4 and 18% for the permanent and temporary pond populations respectively. The reproductive efficiencies for populations of these viviparous clams are greater than those for most oviparous molluscs.The comparative information on the energetics of these populations does not completely fit any theoretical consideration of reproductive effort or life-history strategy. These data are discussed in relation to selection for population success in temporary ponds.Funded in part by grants to Albert J. Burky from the Ohio Biological Survey and the University of Dayton Research CouncilFunded in part by grants to Albert J. Burky from the Ohio Biological Survey and the University of Dayton Research Council  相似文献   
58.
The nature of postsynaptic sites involved in the uptake and metabolism of striatal 3,4-dihydroxyphenylethylamine (dopamine, DA) was investigated. The accumulation of [3H]DA (10(-7) M) into slices of rat striatum was found to be greatly dependent (greater than 99%) on the presence of sodium ion in the incubation medium. However, the formation of the [3H]dihydroxyphenylacetic acid (DOPAC) and [3H]homovanillic acid (HVA) was only partially reduced in the absence of sodium (DOPAC, 27% of control; HVA, 47% of control). Inhibition of carrier-mediated DA neuronal uptake with nomifensine (10(-5) M) significantly decreased DA accumulation (18% of control) and [3H]DOPAC formation (62% of control), but enhanced [3H]HVA production (143% of control). Inhibition of the 5-hydroxytryptamine (5-HT, serotonin) neuronal uptake system with fluoxetine (10(-6) M) or selective 5-HT neuronal lesions with 5,7-dihydroxytryptamine (5,7-DHT) had no effect on [3H]DOPAC or [3H]HVA formed from [3H]DA in the presence or absence of nomifensine. These results demonstrate that the uptake and subsequent metabolism of striatal DA to DOPAC and HVA is only partially dependent on carrier-mediated uptake mechanism(s) requiring sodium ion. These data support our previous findings suggesting a significant role for synaptic glial cell deamination and O-methylation of striatal DA. Further, experiments with fluoxetine or 5,7-DHT suggest that 5-HT neurons do not significantly contribute in the synaptic uptake and metabolism of striatal DA.  相似文献   
59.
The Thy-1 glycoprotein is a very abundant cell surface molecule of rat thymocytes and neuronal cells with the properties of a molecule that inserts into the lipid bilayer. The hydrophobicity is due to a glycophospholipid component covalently attached to the carboxy group of the C-terminal cysteine residue. The mature glycoprotein does not contain a stretch of hydrophobic amino acids that could traverse the membrane bilayer. These findings present a new mode of membrane attachment for a cell surface molecule that can mediate lymphokine release and cell division after cross-linking by antibodies.  相似文献   
60.
We continuously weighed fully distended excised or in situ canine lobes to estimate the fluid filtration coefficient (Kf) of the arterial and venous extra-alveolar vessels compared with that of the entire pulmonary circulation. Alveolar pressure was held constant at 25 cmH2O after full inflation. In the in situ lobes, the bronchial circulation was interrupted by embolization. Kf was estimated by two methods (Drake and Goldberg). Extra-alveolar vessels were isolated from alveolar vessels by embolizing enough 37- to 74-micron polystyrene beads into the lobar artery or vein to completely stop flow. In excised lobes, Kf's of the entire pulmonary circulation by the Drake and Goldberg methods were 0.122 +/- 0.041 (mean +/- SD) and 0.210 +/- 0.080 ml X min-1 X mmHg-1 X 100 g lung-1, respectively. Embolization was not found to increase the Kf's. The mean Kf's of the arterial extra-alveolar vessels were 0.068 +/- 0.014 (Drake) and 0.069 +/- 0.014 (Goldberg) (24 and 33% of the Kf's for the total pulmonary circulation). The mean Kf's of the venous extra-alveolar vessels were similar [0.046 +/- 0.020 (Drake) and 0.065 +/- 0.036 (Goldberg) or 33 and 35% of the Kf's for the total circulation]. No significant difference was found between the extra-alveolar vessel Kf's of in situ vs. excised lobes. These results suggest that when alveolar pressure, lung volume, and pulmonary vascular pressures are high, approximately one-third of the total fluid filtration comes from each of the three compartments.  相似文献   
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