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In the course of a phase I trial, in which recombinant IL-2 (rIL-2) was infused intraperitoneally (i.p.) in patients with peritoneal carcinomatosis, we evaluated the effect on "tumor-associated lymphocytes" (TAL) isolated from the ascitic fluid. No major changes in the percentages of cells expressing the CD3, CD4, CD8, Leu-7, OKM1 and WT-31 antigens were detected either in TAL or in peripheral blood lymphocytes (PBL) after 7 days of rIL-2 infusion. In contrast the percentages of TAL (but not PBL) expressing surface IL-2 receptor (Tac), or LAK-1 antigen were sharply increased. Analysis of cytolytic functions showed a potentiation of the lytic activity against natural-killer (NK) sensitive K562 target cells and the de novo appearance of lytic activity against fresh melanoma cells. In one patient IFN-gamma was detected in the ascitic fluid following rIL-2 infusion. T-cell clones derived from the patient were analyzed for the IFN-gamma production. While only approximately 40% of PB-derived control clones produced medium to low amounts of IFN-gamma, all of the TAL-derived clones produced medium to high amounts of the lymphokine.  相似文献   
23.
Summary The effect ofN-(3,4-dimethoxyphenyl)N-methyl-2-(naphthyl)-m-dithiane-2-propylamine hydrochloride (RO11-2933), an analog of the calcium channel blocker tiapamil, on doxorubicin (DOX)-induced cytotoxicity and DNA damage in human ovarian cancer cells sensitive and resistant to DOX was investigated. A2780-DX2, A2780-DX3, and A2780-DX6 cell sublines were characterized by 7-, 26-, and 48-fold resistance after 2 h DOX exposure and 30-, 50-, and 500-fold resistance after 72 h DOX exposure, respectively. Increased drug efflux resulting in a lower intracellular drug accumulation, decreased DOX-induced DNA single-strand breaks (DNA SSBs), and rapid DNA repair correlated with the degree of resistance. In addition, DNA SSBs were rapidly repaired within 8 h in A2780-DX3 cells, whereas no significant repair of DNA SSBs was observed in sensitive cells. In comparison with verapamil, RO11-2933 was found to reverse DOX resistance at lower and nontoxic concentrations (2 M as compared with 10 M verapamil). This reversion was complete in cells with a low degree of resistance (A2780-DX1 and A2780-DX2) but partial in highly resistant cells (A2780-DX3 and A2780-DX6), and continuous exposure to RO11-2933 was essential for optimal reversal of drug resistance. Interestingly, RO11-2933 was found to inhibit the repair of DNA SSBs induced by DOX but not those induced by X-ray. These results suggest that the potentiation of DNA SSBs and the specific inhibition of DNA repair by RO11-2933 in multidrug-resistant cells could be of particular value in overcoming MDR in the clinic.Abbreviations RO11-2933 N-(3,4-dimethoxyphenethyl)-N-methyl-2-(2-naphthyl)-m-dithiane-2-propylamine hydrochloride - DOX doxorubicin-HCl - SSBs single-strand breaks - MDR multidrug resistance This work was supported in part by CA 18420 and CA 21071  相似文献   
24.
BACKGROUND: It has been argued that lay interviewers' use of fully-structured interviews could lead to a diagnostic pattern different to that by treating physicians. Clinical interviewers in community samples should probably identify cases that are closer to those seen in clinical settings. The greatest advantage of using clinical interviewers consists of the immediate assessment of a possible psychopathology, i.e. the evaluation of current disorders. METHODS: Two thousand three hundred and sixty-three citizens from the community of Sesto Fiorentino, Italy, were interviewed by their own general practitioners using the Mini International Neuropsychiatric Interview (MINI). Positive cases for any lifetime psychiatric disorder as well as a random sample of the negative cases were re-interviewed by psychiatrists or trained residents in psychiatry using the Florence Psychiatric Interview (FPI). RESULTS: The point prevalence for any current disorder was 8.7%; the two disorders with the highest prevalence were generalised anxiety disorder (2.9%) and major depressive episode (2.7%). The figures increase about 50% when the sub-threshold sequelae of previous disorders are considered. Current comorbidity was generally high. The one-year prevalence of any disorder was 10.6%. Ninety-two percent of the cases sought help, 82% were being treated at the moment of interview. Social impairment was considerable. CONCLUSIONS: The period prevalence rates for most of the disorders considered were generally comparable with the range defined by previous studies conducted in other Western countries, despite using different methodologies. Conversely, the use of health facilities, the treatment received and the social impairment were much higher than those reported by the other studies, suggesting a greater similarity with the clinical samples.  相似文献   
25.
Autoantigenic epitope mapping represents a critical issue in autoimmune diseases. The islet tyrosine phosphatase-like protein IA-2/ICA512bdc is a major autoantigen in type 1 diabetes (IDDM), but the epitopes responsible for autoantibody binding have been only partially defined. The aim of our study was to identify ICA512bdc epitopes, and in particular mini-epitopes, utilizing a novel strategy for autoimmune diseases. The study was performed in three sequential steps: (1) construction of a lambda-phage surface-displayed ICA512bdc cDNA library with the methodology of tagged random priming with peptides displayed as a fusion to the C terminus of the capsid protein D; (2) affinity selection of the resulting library, followed by immunoscreening, enzyme-linked immunosorbent assay and sequence analysis of positive clones, and (3) radioimmunoprecipitation to detect autoantibodies to the selected clones. This strategy resulted in the identification of two epitopes (IA-2 residues 761 - 964 and 929 - 979), which were recognized by 100 % and 62.9 % ICA512bdc-positive IDDM patients, respectively. Interestingly, the larger clone was detected also by a proportion (16.7 %) of new onset ICA512bdc-negative patients, thus suggesting that this region contains not only the main autoantigenic repertoire of ICA512bdc molecule, but is able to detect IA-2 autoantibodies in even higher percentages of patients. In addition, this study showed the existence of multiple epitopes located in the C-terminal domain of the IA-2 protein, one of which is formed by the 50 C-terminal amino acids, and provided evidence that the strategy used represents a valid tool for identification of epitopes within autoantigenic molecules.  相似文献   
26.
A total of five Wolf-Hirschhorn syndrome (WHS) patient with a 4p16.3 de novo microdeletion was referred because of genotype-phenotype inconsistencies, first explained as phenotypic variability of the WHS. The actual deletion size was found to be about 12 Mb in three patients, 5 Mb in another one and 20 Mb in the last one, leading us to hypothesize the presence of an extrachromosome segment on the deleted 4p. A der(4)(4qter --> p16.1::8p23 --> pter) chromosome, resulting from an unbalanced de novo translocation was, in fact, detected in four patients and a der(4)(4qter --> q32::4p15.3 --> qter) in the last. Unbalanced t(4;8) translocations were maternal in origin, the rec(4p;4q) was paternal. With the purpose of verifying frequency and specificity of this phenomenon, we investigated yet another group of 20 WHS patients with de novo large deletions (n = 13) or microdeletions (n = 7) and with apparently straightforward genotype-phenotype correlations. The rearrangement was paternal in origin, and occurred as a single anomaly in 19 out of 20 patients. In the remaining patient, the deleted chromosome 4 was maternally derived and consisted of a der(4)(4qter --> 4p16.3::8p23 --> 8pter). In conclusions, we observed that 20% (5/25) of de novo WHS-associated rearrangements were maternal in origin and 80% (20/25) were paternal. All the maternally derived rearrangements were de novo unbalanced t(4;8) translocations and showed specific clinical phenotypes. Paternally derived rearrangements were usually isolated deletions. It can be inferred that a double, cryptic chromosome imbalance is an important factor for phenotypic variability in WHS. It acts either by masking the actual deletion size or by doubling a quantitative change of the genome.  相似文献   
27.
28.
Complete laminin alpha2 (LAMA2) deficiency causes approximately half of congenital muscular dystrophy (CMD) cases. Many loss-of-function mutations have been reported in these severe, neonatal-onset patients, but only single missense mutations have been found in milder CMD with partial laminin alpha2 deficiency. Here, we studied nine patients diagnosed with CMD who showed abnormal white-matter signal at brain MRI and partial deficiency of laminin alpha2 on immunofluorescence of muscle biopsy. We screened the entire 9.5 kb laminin alpha2 mRNA from patient muscle biopsy by direct capillary automated sequencing, single strand conformational polymorphism (SSCP), or denaturing high performance liquid chromatography (DHPLC) of overlapping RT-PCR products followed by direct sequencing of heteroduplexes. We identified laminin alpha2 sequence changes in six of nine CMD patients. Each of the gene changes identified, except one, was novel, including three missense changes and two splice-site mutations. The finding of partial laminin alpha2 deficiency by immunostaining is not specific for laminin alpha2 gene mutation carriers, with only two patients (22%) showing clear causative mutations, and an additional three patients (33%) showing possible mutations. The clinical presentation and disease progression was homogeneous in the laminin alpha2-mutation positive and negative CMD patients.  相似文献   
29.
Alport's syndrome is characterized clinically by a nonimmune glomerulopathy, often accompanied by sensorineural hearing loss and lens abnormalities, frequently due to mutations in the COL4A5 gene. The association of AS with diffuse leiomyomatosis, a benign proliferation of smooth muscle that occurs most often in the esophagus, trachea, and female genitalia, has been reported. Recently, a deletion involving both the COL4A5 and COL4A6 genes has been reported in four unrelated families. We report an additional case with Alport's syndrome associated with leiomyomatosis carrying a deletion of both COL4A5 and COL4A6 genes. A detailed characterization of the genomic region involved in the deletion event has been performed. Our results demonstrate that the deletion removed exon l of COL4A5 and exons l and 2 of COL4A6. © 1994 Wiley-Liss, Inc.  相似文献   
30.
Potocki–Lupski syndrome is a condition mainly characterized by infantile hypotonia, developmental delay/intellectual disability (DD/ID), and congenital anomalies, caused by duplications of the 17p11.2 region, encompassing RAI1 gene. Its clinical presentation is extremely variable, especially for what concerns the cognitive level and the behavioral phenotype. Such aspects, as well as the dysmorphic/malformative ones, have been covered by previous studies; otherwise neurological features have never been systematically described. In order to delineate the neurological phenotype of Potocki–Lupski Syndrome, we collect an 8‐patients cohort. Developmental milestones are delayed and a mild to moderate cognitive impairment is present in all patients, variably associated with features of autism spectrum disorder, behavioral disturb, and sleep disturb. Hypotonia appears a less frequent finding than what previously reported, while motor clumsiness/coordination impairment is frequent. EGG registration demonstrated a common pattern with excess of diffuse rhythmic activity in sleep phases or while the patient is falling asleep. Brain MRI did not reveal common anomalies, although unspecific white matter changes may be present. We discuss such findings and compare them to literature data, offering an overview on the neurological and cognitive‐behavioral presentation of the syndrome.  相似文献   
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