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71.
Induction of IL-5 expression by IL-2 is resistant to the immunosuppressive agents cyclosporin A and rapamycin 总被引:1,自引:0,他引:1
T cell cytokine expression may be induced by the cytokine IL-2 or via the
TCR complex. The comparative effects of cytokine- and TCR-mediated
signalling on the induction of human IL-5 mRNA were examined. Cytokine mRNA
expression was analysed by RT-PCR in fresh peripheral blood mononuclear
cells (PBMC) from normal individuals and in populations of activated T
lymphocytes, derived from phytohaemagglutinin (PHA)- stimulated PBMC. rIL-2
induced IL-5 expression in PBMC, the kinetics of which were similar to the
effects of PHA. rIL-4 induced IL-5 mRNA expression in activated T
lymphocytes. IL-5 expression induced by either IL-2 or PHA was completely
abolished by the protein synthesis inhibitor cycloheximide. rIL-2-induced
IL-5 expression was resistant to cyclosporin A (CsA), whereas IL-5
expression elicited by PHA was inhibited by CsA, at doses as low as 10
ng/ml. Rapamycin (RAP) had no effect on rIL-2-stimulated IL-5 expression,
but suppressed IL-5 expression induced by PHA. The inhibitory effect of RAP
on PHA-induced IL-5 expression was more apparent at 12 and 24 h after
stimulation than at earlier times. The resistance of IL-2 receptor (IL-2R)
signalling to CsA and RAP indicates that the IL-2R and the TCR are
associated with different pathways regulating IL-5 expression.
相似文献
72.
X-linked hypophosphatemia in adults: prevalence of skeletal radiographic and scintigraphic features 总被引:3,自引:0,他引:3
The radiologic studies of 38 essentially untreated adults with X-linked hypophosphatemia (XLH) were reviewed to determine the prevalence of radiologic features, to compare the findings in men and in women, and to elucidate the natural history of the disease by comparing the findings in young, intermediate-age, and older patients. Bone-reinforcement lines were common, but no characteristic mineral mass alteration was established. Looser zones were more prevalent in older subjects. Osteoarthritis was common, occurring in the ankles, knees, feet, sacroiliac joints, and wrists. Enthesopathy was infrequent in the younger group but was present in every member of the intermediate and older groups and was often accompanied by extra ossicles. Curvatures of the lower-extremity long bones were common in all age groups. Three new skeletal alterations in XLH were found to be common: flaring of the iliac wings, trapezoidal distal femoral condyles, and alterations in talar morphology, including shortening of the talar neck and flattening of the talar dome. Technetium-99m methylene diphosphonate scintigrams of 17 subjects were often abnormal, depicting bowing deformity and focal tracer accumulation in diaphyseal cortices and in periarticular and extraarticular regions. The mean metabolic index was moderately elevated (4.0). Both radiographic and scintigraphic findings were more severe in men, consistent with hemizygosity. The natural history of untreated XLH in both sexes is characterized by the development of a variety of age-related skeletal abnormalities during adulthood. 相似文献
73.
74.
75.
DAO JIE LIU YING LIU ZHUO LI YAN YAN JI MING YIN WA HAO JIN QIN NIU FANG LIU XIAN CHUN XIE HUI LI 《中华微生物学和免疫学杂志(英文版)》2007,5(2):133-138
The aim of this study is to investigate whether three mononucleotide polymorphisms at the locus -1082,-819 and -592 in the promoter region of the IL-10 gene are associated with chronic severe hepatitis. The IL-10-592 and IL-10-1082 polymorphisms were genotyped by polymerase chain reactionrestriction fragment length polymorphism analysis (PCR-RFLP) while polymerase chain reaction-sequence specific primer (PCR-SSP) assay was used to test the IL-10-819 polymorphism. The polymorphisms of IL-10-1082, -819 and -592 genes were detected in 98 patients with chronic severe hepatitis (CSH), 478 patients with chronic hepatitis B (CHB), 223 asymptomatic (chronic) HBV carriers (ASC) and 267 patients with self-restricted HBV. There was significant difference of the polymorphisms of IL-10-1082, IL-10-819 and IL-10-592 genes between CSH group and other groups. The frequency of AA genotype at IL-10 gene promoter -1082 locus in chronic severe hepatitis patients was higher than that in asymptomatic HBV carriers (2 = 13. 314, P = 0.001), and self-restricted HBV patients (χ^2 = 13.545, P = 0.000); the frequency of CC and AC genotype at IL-10 gene promoter -592 locus in chronic severe hepatitis patients was higher than that in chronic hepatitis patients(χ^2 = 15.970, P=0.000) (χ^2 =20.414, P=0.000), asymptomatic HBV carriers (χ^2 =21.283, P= 0.000) (χ^2 = 28.309, P = 0.000) and self-restricted HBV patients(χ^2 = 17.047, P = 0.000) (χ^2 = 16.528, P = 0.000) ; the frequency of TC genotype at IL-10 gene promoter -819 locus in chronic severe hepatitis patients was higher than that in chronic hepatitis patients(χ^2 = 58.961, P = 0.000), asymptomatic HBV carriers ( χ^2 = 53. 255, P = 0. 001 ) and self-restricted HBV patients (χ^2 = 39.616, P = 0.001). So interleukine-10 gene polymorphism was associated with the chronic severe hepatitis. 相似文献
76.
77.
Breast specimen radiography: evaluation of a compression device 总被引:1,自引:0,他引:1
The irregular shape and uneven tissue thickness of excised breast specimens makes radiographic evaluation difficult, especially when calcifications are not present. Xeroradiographs before and after compression of 20 separate excised breast specimens were compared, and 17 of the same specimens were compared after compression combined with immersion in water. Specimen compression improved visibility of the lesion on average in 88% of cases, and visibility was equal in 12%. Combined compression/immersion further improved visibility of the lesion on average in 37% of cases. More significantly, evaluation of the compressed specimen led to a change in interpretation of the radiographs in 45% of cases. Compression of the specimen in specimen radiography is recommended in all cases in which pre-biopsy localization is performed. 相似文献
78.
WA ARIFFIN S KARNANEEDI KE CHOO J NORMAH 《Journal of paediatrics and child health》1996,32(2):191-193
Between January 1985 and June 1992, the Paediatric Department of Hospital Universiti Sains Malaysia has diagnosed congenital dyserythropoietic anaemia in three children, two of whom were siblings. The age of onset ranged from 1 to 3 years. All of them became transfusion-dependent before the age of 4 months. One of them was successfully treated with bone marrow transplantation. 相似文献
79.
Pressure, or compressive, erosions of bone in various locations in patients with rheumatoid arthritis are described. Possible pathophysiologic mechanisms that account for the appearance and distribution of these erosions include osteopenia, soft-tissue laxity, soft-tissue pressure on bone, bone pressure on bone, and muscular forces. 相似文献
80.
L-Methylmalonyl-CoA mutase (MUT) is an adenosylcobalamin (AdoCbl)-
requiring mitochondrial matrix enzyme that catalyzes the isomerization of
L-methylmalonyl-CoA to succinyl-CoA. Inherited defects in the gene encoding
this enzyme result in the mut forms of methylmalonic acidemia. Expression
of mature human MUT cDNA in Escherichia coli at a post- induction
cultivation temperature of 12 degrees C, rather than 37 degrees C, led to
the folding of the majority of the synthesized protein to a soluble form,
with an activity of 0.2-0.3 U/mg protein in the cell-free extract, 10-15
times higher than that in human liver homogenate. Six missense mutations,
producing the amino acid changes G94V, Y231N, R369H, G623R, H678R and
G717V, were detected in MUT cDNA of patients suffering from the mut- form
of methylmalonic acidemia, resulting from defective AdoCbl binding. Two
(G623R and G717V) had been reported in other patients. Three (G94V, Y231N
and R369H) are the first changes in the NH2-terminal part of the enzyme
reported to cause the mut- phenotype. Enzymes with the mutations were
individually expressed, and their kinetic parameters were generally in
accord with published biochemical data from extracts of fibroblasts from
these patients. The mutations increased the K(m) for AdoCbl by 40- to
900-fold, while V(max) values varied from 0.2% to nearly 100% of that of
wild-type protein. In one case of a doubly heterozygous cell line, however,
neither of the constituent mutant enzymes had a K(m) corresponding to the
lower of the two estimated from the extract data. This finding may reflect
the natural occurrence of interallelic complementation in vivo in this cell
line.
相似文献