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21.
Aims—To determine the role of insulin-like growth factors (IGF) in the proliferation of tumour cells, by studying the mitogenic response to IGFs of three cell lines of differing phenotype established from both malignant rhabdoid and Wilms tumour, representing a range of cell types (GOS 4, G401, and T3/73). 相似文献
22.
The effect of the growth state of a cell on the ability of hyperthermia to induce the synthesis of heat shock proteins (HSPs) was studied in resting and concanavalin A (ConA)-stimulated lymphocytes. Hyperthermia induced the synthesis of hsp 110, hsp 90, hsc 70, and hsp 70 in both resting and ConA-stimulated lymhocytes, and ConA-treatment induced the synthesis of the hsp 90 and hsc 70 at normal temperature. The induction of the synthesis of hsp 110 and hsp 70 by hyperthermia was 3- to 6-fold higher for lymphocytes cultured with ConA for 12 and 24 h than in non-stimulated lymphocytes. Thus, lymphocytes induced to undergo proliferation showed a greater response to hyperthermia than resting lymphocytes. 相似文献
23.
John L. Johnson Hiroe Shiratsuchi Zahra Toossi Jerrold J. Ellner 《Journal of clinical immunology》1997,17(5):387-395
The pathophysiologic basis for the exuberant intracellular growth of Mycobacterium avium complex (MAC) in AIDS patients is unclear but may relate to altered expression of modulatory cytokines. Interleukin (IL)-1, IL-6, and TNF- expression by monocytes from AIDS patients and healthy subjects (HS) stimulated with isogeneic MAC strains (SmT, smooth-transparent, virulent; SmD, smooth-domed, avirulent) was examined. Spontaneous cytokine production was not observed in patients with AIDS. MAC strains induced less IL-1 and IL-1 release in AIDS patients than HS (P < 0.05). The ratio of cell-associated to supernatant IL-1 also was increased in AIDS patients (P = 0.03). IL-1 mRNA expression paralleled protein release in either group of subjects. In both HS and AIDS patients, stimulation with SmD induced more IL-1 and TNF- release by monocytes compared to SmT. In AIDS patients, SmD also induced greater IL-6 release than SmT (P < 0.01). Alterations in monocyte expression and compartmentalization of the regulatory cytokines IL-1 and IL-6 may enhance bacterial replication and contribute to the patho-genesis of MAC infection in AIDS. 相似文献
24.
Giulia Barcia Marlne Rio Zahra Assouline Coralie Zangarelli Charles-Joris Roux Pascale de Lonlay Julie Steffann Isabelle Desguerre Arnold Munnich Jean-Paul Bonnefont Nathalie Boddaert Agns Rtig Metodi D. Metodiev Benedetta Ruzzenente 《European journal of human genetics : EJHG》2021,29(3):533
Mitochondrial translation is essential for the biogenesis of the mitochondrial oxidative phosphorylation system (OXPHOS) that synthesizes the bulk of ATP for the cell. Hypomorphic and loss-of-function variants in either mitochondrial DNA or in nuclear genes that encode mitochondrial translation factors can result in impaired OXPHOS biogenesis and mitochondrial diseases with variable clinical presentations. Compound heterozygous or homozygous missense and frameshift variants in the FARS2 gene, that encodes the mitochondrial phenylalanyl-tRNA synthetase, are commonly linked to either early-onset epileptic mitochondrial encephalopathy or spastic paraplegia. Here, we expand the genetic spectrum of FARS2-linked disease with three patients carrying novel compound heterozygous variants in the FARS2 gene and presenting with spastic tetraparesis, axial hypotonia and myoclonic epilepsy in two cases.Subject terms: Metabolic disorders, Mutation 相似文献
25.
The effect of ovarian steroids on epithelial ciliary beat frequency in the human Fallopian tube 总被引:3,自引:3,他引:3
Mahmood T; Saridogan E; Smutna S; Habib AM; Djahanbakhch O 《Human reproduction (Oxford, England)》1998,13(11):2991-2994
Using a method that detects variations in light intensity we have studied
the effect of ovarian steroids on human Fallopian tube epithelial ciliary
beat frequency in vitro. We have found that baseline ciliary beat frequency
averages between 5-6 Hz. Cilia from ampullary segments of the Fallopian
tube beat significantly faster (5.4 Hz+/-0.2) than those from fimbrial
segments (4.8 Hz+/-0.2). There was no significant difference in baseline
ciliary beat frequency at any other anatomical site in the Fallopian tube.
Incubation with progesterone (10 micromol/l) suppresses human Fallopian
tube epithelial ciliary beat frequency by 40-50%. This inhibition was
observed at similar magnitudes in all Fallopian tubes studied irrespective
of anatomical site. Progesterone-induced reductions in ciliary beat
frequency were concentration dependent and prevented by the progesterone
receptor antagonist mifepristone (RU486). Oestradiol alone (10 micromol/l)
had no effect on ciliary beat frequency at any anatomical site in the
Fallopian tube but did prevent the reduction in ciliary beat frequency seen
with progesterone when tissues were incubated with these two steroids
together.
相似文献
26.
The identification of biomaterials that induce optimal gene expression patterns and allow for appropriate levels of cellular attachment is of central importance in tissue engineering and cell therapy. Herein, we describe the creation of cell-compatible, biomaterial microarrays, that allow rapid, microscale testing of biomaterial interactions with cells. As proof of principle, we simultaneously characterized over 3456 human mesenchymal stem cell (hMSC)-biomaterial composite interactions, and describe preliminary studies on the utility of these arrays with a neural stem cell line (NSC), and primary articular chondrocytes. 相似文献
27.
Ana L Sanchez Carrie M Langdon Mahmood Akhtar Jun Lu Carl D Richards Premysl Bercik Derek M McKay 《Journal of interferon & cytokine research》2003,23(4):193-201
The use of biologics has promising potential in the treatment of inflammation. Studies with cultured cells and mouse models of disease have ascribed proinflammatory and anti-inflammatory functions to oncostatin M (OSM) and the related cytokine, interleukin-6 (IL-6). Here, we examined the effect of systemic administration of adenoviral (Ad) vectors encoding either murine OSM (AdMuOSM) or murine IL-6 (AdMuIL-6) in a mouse model of colitis. BALB/c mice were treated with a 5-day course of 4% dextran-sodium sulfate (DSS) water with or without administration of adenoviral vectors (i.p. or i.m. at 10(7) plaque-forming units [pfu]) given as a cotreatment or therapy. The deletion variant of the adenovirus served as a control for adenoviral infection. Colitis was assessed by (1) morphology (damage score, macrophage infiltration, apoptosis) and (2) function (myeloperoxidase activity and Ussing chamber analysis of epithelial ion transport). Infection with adenovirus alone did not affect colonic form or function. AdMuOSM (either i.p. or i.m.) significantly reduced the severity of the DSS-induced colitis. There was less damage, reduced macrophage infiltration, fewer apoptotic bodies, and a significant improvement in stimulated ion transport in colonic tissues from the treated mice. No benefit of AdMuIL-6 treatment was observed in this model system. Thus, systemic administration of AdMuOSM given as a cotreatment and to a lesser extent as a therapy was found to be of benefit in DSS-induced colitis, a murine model of inflammatory bowel disease (IBD). 相似文献
28.
Of 1,500 cervical tissue specimens, 27 cases showed histologic changes of reactive glandular atypia which we defined as endocervical cells with large hyperchromatic, often irregular nuclei, which did not fulfill the criteria for endocervical adenocarcinoma. Eighteen of these 27 cases had preceding or concurrent cervico-vaginal smears. Six of these showed cells which were similar to those seen in histologic sections. The cytologic characteristics of these cells are defined. To determine if atypia is related to inflammatory-regenerative changes, 29 cases of endocervical polyps were examined, of which 11 showed histologic changes of endocervical reactive atypia; 4 showed these changes cytologically as well. Twenty-eight cases of routine hysterectomy specimens were examined, of which 2 cases showed endocervical reactive atypia, which indicated that the atypical changes were indeed reactive. Nine out of 27 cases were associated with hormonal usage. Fourteen cases were associated with squamous intraepithelial lesions or evidence of human papilloma virus. Follow-up of our 27 index cases revealed no progression to adenocarcinoma. These findings indicate that atypia, as we define it, of the endocervix can be due to inflammatory-reparative changes or possibly related to hormonal usage, and permit its separation from precursor lesions of endocervical adenocarcinoma. 相似文献
29.
Ghamar Taj Khotaei Leyla Sedighipour Fatemeh Fattahi Zahra Pourpak 《Journal of microbiology, immunology, and infection》2006,39(2):169-172
Bacille Calmette-Guérin (BCG) osteomyelitis is a very rare complication of BCG vaccination. We report a 14-month-old boy who received BCG vaccination at birth. He developed pain and swelling in his left calf at 11 months of age. BCG osteomyelitis was diagnosed in right femur and left tibia. He had no evidence of immunodeficiency. After antituberculous therapy and surgical treatment, the bone lesions disappeared and he was discharged from hospital without any sequela during 11 months of follow-up. 相似文献
30.
Chromosome 13q neocentromeres: molecular cytogenetic characterization of three additional cases and clinical spectrum 总被引:3,自引:0,他引:3
Li S Malafiej P Levy B Mahmood R Field M Hughes T Lockhart LH Wu Z Huang M Hirschhorn K Velagaleti GV Daniel A Warburton PE 《American journal of medical genetics》2002,110(3):258-267
We report three new cases of chromosome 13 derived marker chromosomes, found in unrelated patients with dysmorphisms and/or developmental delay. Molecular cytogenetic analysis was performed using fluorescence in situ hybridization (FISH) with chromosome-specific painting probes, alpha satellite probes, and physically mapped probes from chromosome 13q, as well as comparative genomic hybridization (CGH). This analysis demonstrated that these markers consisted of inversion duplications of distal portions of chromosome 13q that have separated from the endogenous chromosome 13 centromere and contain no detectable alpha satellite DNA. The presence of a functional neocentromere on these marker chromosomes was confirmed by immunofluorescence with antibodies to centromere protein-C (CENP-C). The cytogenetic location of a neocentromere in band 13q32 was confirmed by simultaneous FISH with physically mapped YACs from 13q32 and immunofluorescence with anti-CENP-C. The addition of these three new cases brings the total number of described inv dup 13q neocentic chromosomes to 11, representing 21% (11/52) of the current overall total of 52 described cases of human neocentric chromosomes. This higher than expected frequency suggests that chromosome 13q may have an increased propensity for neocentromere formation. The clinical spectrum of all 11 cases is presented, representing a unique collection of polysomy for different portions of chromosome 13q without aneuploidies for additional chromosomal regions. The complexity and variability of the phenotypes seen in these patients does not support a simple reductionist view of phenotype/genotype correlation with polysomy for certain chromosomal regions. 相似文献