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21.
Despite the combined use of surgery and chemoradiotherapy, the poor prognosis of advanced non-smallcell lung cancer (NSCLC) requires the definition of new therapeutic approaches. The presence of T lymphocytes, with peculiar phenotypic, functional and molecular characteristics within the tumour, suggested the possible use of these cells, expanded in vitro, in protocols of adoptive immunotherapy. We have described how a population of oligoclonal T lymphocytes, derived from advanced NSCLC, can be expanded in vitro and has the capability of lysing autologous cancer cells. What is more important, we observed that patients with advanced NSCLC, treated with TIL expanded in vitro and recombinant interleukin-2, seemed to have a disease-free period longer than that of patients treated with conventional chemoradiotherapy. in an attempt to find new sources of specific lymphocytes for immunotherapy, we describe the analysis of the phenotypic, functional and molecular characteristics of T lymphocytes, derived from lymph nodes draining advanced NSCLC. In this paper we show that these cells, have restriction patterns of T cell receptor chain similar to those detectable in the population of infiltrating T lymphocytes. This finding suggests that T cells derived from draining lymph nodes of advanced NSCLC have peculiar characteristics and can be a suitable source of effector cells for protocols of adoptive immunotherapy in lung cancer treatment.  相似文献   
22.
The coupling of the analysis of the absorption and circular dichroism (CD) spectra with that of the cholesteric mesophases induced in nematic liquid crystals indicated some interesting conformational features of bridged and nonbridged mono- and dialkylethers of optically active 2,2′-dihydroxy-1,1′-binaphthalene. Bridged derivatives are characterized by relatively small dihedral angles. Simple monoalkyl ethers are characterized by larger dihedral angles but they all assume an s-cis conformation, owing to the existence of intramolecular hydrogen bonds. Nonbridged dialkylethers prefer even larger dihedral angles and, depending on the bulkiness of the alkyl groups, the s-trans conformation can be found. Interestingly, the conformation of dialkylethers is strongly dependent on the structure of the liquid crystal solvent, because the intramolecular hydrogen bond is not possible there. © 1995 Wiley-Liss, Inc.  相似文献   
23.
Protein-carbohydrate interactions are supposed to play key roles in the mechanisms of cell adhesion, biosignalling and intracellular routing, warranting the analysis of the developmental course of expression of epitopes of this system. Thus, a panel of carrier-immobilized carbohydrate ligands was used as probes, namely lactose,N-acetylgalactosamine,N-acetylglucosamine, mannose, fucose and maltose. Additionally, an antibody to an endogenous -galactoside-binding lectin (anti-galectin-1), the biotinylated lectin and two further human lectins, namely the macrophage migration inhibitory factor-binding sarcolectin and serum amyloid P component (SAP) that displays selectivity for sulphated sugars and mannose-6-phosphate, were included. They enabled us to assess the extent of the presence of respective binding sites in fixed sections from human lungs (pulmonary epithelial cells), livers (hepatocytes) and hearts (myocard cells) of 10–50 weeks gestation. Invariably, specific binding was detected in the three organ types, at least in certain stages. In most of the cases, the intensity of staining exhibited developmental regulation. The apparent patterns reveal similarities between the different cell types, as seen with immobilizedN-acetylglucosamine as well as with labelled galectin-1 and sarcolectin. However, drastic differences among such patterns with nearly opposite developmental courses do also occur, as detected for carrier-attached mannose and maltose residues. These results point to a potential importance for the detected glycohistochemical features in human development and substantiate the possibility of differential regulation of the presence of binding sites for distinct sugars within a certain organ and between the individual cell types of the monitored organs.  相似文献   
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The X-ray diffraction and i.r. absorption conformational analysis of N-tert-butyloxycarbonyl-l-phenylalanine has showed the absence of intramolecularly hydrogen-bonded peptide conformations in the solid state. The molecules are held together in rows of ‘cyclic dimer’ motifs through intermolecular NHOC (acid) and OHOC {urethane} hydrogen bonds, the secondary amide-like group of the urethane moiety being in the unusual cis conformation, whereas the carboxylic acid group in the common syn conformation. The two molecules in the unit cell present a centrosymmetric set of ?, ψ1, and ψ2 values. In polar solvents solvated species largely predominate. In saturated hydrocarbon solution non-associated and associated (mostly involving the carboxylic acid CO as the proton acceptor) species simultaneously occur. The extent of association decreases with dilution. The amount of intramolecularly hydrogen-bonded oxy-C7 and C5 forms if any, should be extremely small. The type of association at saturation seems to differ from that found in the crystalline compound obtained by precipitation with saturated aliphatic hydrocarbons (from a diethyl ether solution).  相似文献   
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Summary From November 1973 to December 1974, 20 patients with advanced malignant melanoma were treated with BCG given by intralymphatic route at the Cancer Institute of Milan. The lyophilized Pasteur BCG was used. Patients were treated with a single dose ranging from 0.2–80 mg. Patients' performance status was never severely impaired.The most frequent side effects were fever, lymphangitis, and lymph node enlargement.Variations were observed in white cell count, ERS and immunoglobulins; in no case did we find evidence of liver toxicity or tumor growth enhancement. It is concluded that the intralymphatic route is a safe way of administrating BCG.  相似文献   
28.
Summary It has been suggested that the generation of toxic radicals plays an important role in toxicity by Adriamycin (ADR) on cancer cell lines and in vivo. We have examined the role of free radicals in determining toxicity and resistance to ADR of rat glomerular epithelial cells in culture; this method provides a good model for analyzing the mechanisms responsible for ADR experimental nephrosis in rats. Three points were established: a) the intra- or extracellular site of ADR toxicity; b) the role of the superoxide anion and of the hydroxyl radical in determining intra- and-extracellular cytotoxicity; and c) the implication of oxido-reduction cycling as a potential route for ADR semiquinone transformation. Free ADR was found to induce the same inhibition of [3H]thymidine incorporation into DNA as ADR bound to an agarose macroporous bed which prevents the intracellular incorporation of the drug. Specific scavenging of free radical activity by the enzymes catalase and superoxide dismutase, the hydroxyl radical inhibitors dimethyl sulfoxide and dimethylthiourea (DMTU) and by chelation of intracellular free iron with deferoxamine produced only a partial restoration of [3H]thymidine incorporation into DNA, which was maximal for DMTU (30% of normal incorporation). DMTU treatment was unsuccessful in preventing the extracellular cytostatic effect of ADR. Finally, glomerular epithelial cell killing (51Cr-release method) by 5-iminodaunorubicin, an ADR analogue with a modified quinone function that prohibits oxido-reduction cycling, was higher than unmodified ADR. These results indicate that ADR may exert its cytotoxic effects on glomerular epithelial cells by interaction at the cell surface, whereas the intracellular compartment, principally DNA, does not seem to be the target of ADR effects. They also suggest that the free radicals are in part responsible for ADR intracellular cytotoxicity, but other mechanisms should also be hypothesized. Finally, the participation of the ADR semiquinone radical in oxido-reduction cycling seems not important for the induction of the cellular damage.  相似文献   
29.
Summary A model of a thoracolumbar somite of a chick embryo at the 53rd incubation hour was obtained by mathematical methods, after identification of somite cell types by means of electron microscopy.Each specific district occupied by the cell types was precisely determined.On the basis of these observations, the somite was three-dimensionally reconstructed and the spatial positions of the primitive myotome, dermatome, sclerotome, undifferentiated mesoderm and myocele were precisely identified.  相似文献   
30.
The problem of the quantitative determination of sulfoxide groups in peptide molecules has been re-examined. The approaches currently available for the estimation of δ-sulfoxide amino acids are limited in number and characterized by serious shortcomings; in addition, the choice of methods for the estimation of γ-sulfoxide amino acids is even more restricted. A new, rapid, and nondestructive direct method for determining quantitatively all types of sulfoxides in peptide molecules by using x-ray photoelectron spectroscopy is described.  相似文献   
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