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41.
An acid phosphatase from derepressed cells of the yeast form of Yarrowia lipolytica was purified 176-fold by ammonium sulfate precipitation, chromatography on DEAE-Sephacel and gel filtration in Biogel A 5-M. The enzyme is a glycoprotein with a sugar content of 60%. The MICHAELIS constant of the enzyme is 5.5 × 10?4 M for p-nitrophenyl phosphate as substrate; the isoelectric point estimated by electrofocusing is around 4.6 and the optimum pH is 6.2. Phosphatase activity was destroyed by exposure of the enzyme to 40 °C for 30 min or at pH 3 for 30 min. The purified enzyme shows size heterogeneity within a linear concentration gradient of polyacrylamide (4–20%) which indicates an apparent molecular weight in the range of 90,000–200,000 in the presence of sodium dodecyl sulfate. The heterogeneity of the enzyme is due to its carbohydrate content, as can be demonstrated by gel filtration and by treatment with endoglycosidase H. The carbohydrate-depleted protein has a molecular weight of 60,000. Aminoacid analysis revealed a high content of aspartic acid, serine, threonine, glycine and alanine. Antibodies against the protein moiety show cross reactivity with the acid phosphatase of Saccharomyces cerevisiae. 相似文献
42.
43.
Changes in the human immunodeficiency virus p7-p1-p6 gag gene in drug-naive and pretreated patients 下载免费PDF全文
Resistance to antiretroviral agents often results from mutations within the human immunodeficiency virus (HIV) pol gene. Moreover, insertions within the p6 gag-pol region have recently been found to be involved with resistance to nucleoside analogs. Overall, we found that 21% of 156 specimens collected from HIV-infected individuals (17.6% from 74 drug-naive patients and 24.4% from 82 pretreated patients) harbored these insertions. Insertions around the KQE (Lys-Gln-Glu) motif were found in 12.2% of the pretreated patients but in none of the drug-naive subjects (P = 0.002). In contrast, insertions around the PTAP (Prol-Thre-Ala-Prol) motif were seen at similar rates ( approximately 15%) among drug-naive and pretreated patients, which supports the idea that they may be natural polymorphisms. 相似文献
44.
Asturias JA Eraso E Arilla MC Gómez-Bayón N Inácio F Martínez A 《International archives of allergy and immunology》2002,128(2):90-96
BACKGROUND: Gastropod consumption is quite frequent in the Mediterranean countries and cross-reactivities with crustaceans have been described, but the mechanism of this allergenic cross-reactivity has not been studied in detail. This study aimed to produce recombinant Helix aspersa (brown garden snail) tropomyosin and investigate its implication for cross-reactivity among invertebrates. METHODS: A tropomyosin-specific cDNA encoding H. aspersa tropomyosin was synthetized, and recombinant allergen was overexpressed in Escherichia coli as nonfusion protein. IgE-binding reactivity was studied by immunoblotting and immunoblot inhibition experiments with sera from snail-allergic patients. RESULTS: Cloned brown garden snail tropomyosin shares high homology with other edible mollusk tropomyosins (84-69% identity) as well as with those from arthropods (65-62%), and less homology with vertebrate ones (56% identity). Tropomyosin reacted with 18% of the sera from patients with snail allergy. Inhibition experiments, using natural and recombinant tropomyosins, showed different degrees of cross-reactivity between invertebrate tropomyosins. Sera from snail-allergic subjects recognized tropomyosins in both mollusks and crustacean extracts. CONCLUSIONS: Tropomyosin represents a minor allergen in snail extracts, but it is clearly involved in invertebrate cross-reactivity. 相似文献
45.
Two siblings presenting slight mental retardation showed an abnormal elimination of histidine, their blood levels for the same amino acid being normal. The percentage of tubular resorption of histidine was calculated in both boys, and the values were 40.1 per cent (case 1) and 52.8 per cent (case 2). All other amino acids essayed were normal. After an oral overload test with histidine, a low intestinal absorption was found in the two boys, the values of this test in the parents being intermediate between those of the children and of the three normal controls and corresponding to heterozygosity. In view of the studies carried out on the two boys, it is possible to conclude that they are suffering from an impairment in their histidine membrane transport system which affects the kidney and intestines. Since they are siblings a genetically determined trait may be suspected. 相似文献
46.
Campos B Díez O Odefrey F Domènech M Moncoutier V Martínez-Ferrandis JI Osorio A Balmaña J Barroso A Armengod ME Benítez J Alonso C Stoppa-Lyonnet D Goldgar D Baiget M 《Human mutation》2003,21(4):452-452
A frame-shift 9254del5 mutation was independently identified in 12 families, eleven of them with Spanish ancestors, in a BRCA2 screening performed in 841 breast and/or ovarian cancer families and in 339 women with breast cancer diagnosed before the age of 40 at different centers in France and Spain. We sought to analyze in detail the haplotype and founder effects of the 9254del5 and to estimate the time of origin of the mutation. Eight polymorphic microsatellite markers and two BRCA2 polymorphisms were used for the haplotype analyses. The markers were located flanking the BRCA2 gene spanning a region of 6.1 cM. Our results suggest that these families shared a common ancestry with BRCA2 9254del5, which is a founder mutation originating in the Northeast Spanish, with an estimated age of 92 (95% CI 56-141) generations. 相似文献
47.
Marta Pacio Miguez Fernando Santos‐Simarro Sixto García‐Miñaúr Ramón Velázquez Fragua Ángela del Pozo Mario Solís Carmen Jiménez Rodríguez Virginia Rufo‐Rabadán Victoria Eugenia Fernandez Inmaculada Rueda Maria Victoria Gomez del Pozo Natividad Gallego Pablo Lapunzina María Palomares‐Bralo 《American journal of medical genetics. Part A》2020,182(10):2222-2225
48.
Arroyo JC Gabilondo F Llorente L Meraz-Ríos MA Sánchez-Torres C 《Journal of clinical immunology》2004,24(1):86-96
Monocyte-derived dendritic cells (mDC) are increasingly used as cancer vaccines. However, human monocytes are a heterogeneous cell population. We showed previously that DC derived from a monocyte subset expressing CD16 (16+mDC) stimulated allogeneic naïve T lymphocytes to secrete higher levels of IL-4 than DC derived from regular CD14highCD16? monocytes (16?mDC). Th1-type responses have been associated with effective antitumor responses, thus the use of mDC containing 16+mDC as cancer vaccines might be disadvantageous. Here, we evaluate the primary and memory immune response elicited in vitro by 16+mDC and 16?mDC in five patients with metastatic renal cell carcinoma vaccinated with autologous mDC pulsed with tumor lysates (TuLy) and keyhole limpet hemocyanin (KLH). After therapy, three of the five patients had stable disease. Surprisingly, patients with longer survival showed the highest amount of peripheral blood CD16+ monocytes. Analysis of KLH-specific antibodies revealed high titers of IgG2 in patients with longer survival. CD4+ T lymphocyte proliferation against KLH and TuLy increased after treatment, and some patients showed an augmented rate of CD4+ T lymphocyte proliferation against KLH (3/5) and TuLy (2/3) when 16+mDC were used as antigen presenting cells (APC). Before treatment, the IFN-γ/IL-4 ratio against TuLy and KLH was higher when using 16?mDC as APC, but after vaccination four of five patients had an increased ratio for TuLy with 16+mDC. These results suggest that the immune response elicited by 16?mDC and 16+mDC is modified when memory or naïve T cells are stimulated, and 16+mDC could favor a stronger and more beneficial antitumoral Th1 memory response in vivo. 相似文献
49.
Esmer C Urraca N Carnevale A Del Castillo V 《American journal of medical genetics. Part A》2004,(2):162-166
Children with genetic diseases must be followed for long periods of time to seek new findings. Other patients require further check-ups and studies to be diagnosed. Some patients never return for medical care after the first consultation, which may have serious consequences. We reviewed 400 medical charts of patients with genetic disease to analyze overall attendance to the genetics clinic, investigate some of the causes of failure to seek medical advice, and determine the differences between those first seen as outpatients or as inpatients. The mean follow-up period was 8.3 months (range 0-79), and the average number of visits was 2.8 (range 1-16). Forty eight percent of the cases first seen as inpatients were evaluated only once and 14% twice; while 22 and 21% of the 300 cases first seen as outpatients attended once and twice, respectively (P = 0.0). Appointment keeping was apparently not affected by the presence or absence of diagnosis. Overall, 97 patients were discharged, 7 died, 55 continued on follow-up, 62 attended other hospital services-but not genetics-and 179 were completely lost to follow-up. Diagnosed patients were counseled more frequently than undiagnosed patients (62 vs. 5%); and 71% of the diagnosed patients first seen as outpatients but only 36% of undiagnosed cases first seen as inpatients were counseled, differences between these two groups were significant (P = 0.005). We conclude that keeping the patient with genetic disease on follow-up is a difficult task. New educational strategies must be planned to improve this worrisome situation. 相似文献
50.
Maria Suárez-Cervera Teresa Castells Ana Vega-Maray Esther Civantos Victoria del Pozo Delia Fernández-González Stella Moreno-Grau Angel Moral Carmen López-Iglesias Carlos Lahoz Juan A Seoane-Camba 《Annals of allergy, asthma & immunology》2008,101(1):57-66
BACKGROUND: Cupressaceae is a family of plants resistant to airborne contamination, and its pollen is the main cause of winter allergic respiratory diseases, especially in North America, Japan, and Mediterranean countries. Recently, a major allergen from Cupressus arizonica pollen grains, Cup a 3, was cloned and expressed. OBJECTIVE: To study the effects of air pollution on the expression of Cup a 3, a thaumatinlike protein, in C. arizonica pollen grains using a combination of transmission electron microscopy and immunocytochemical techniques. METHODS: Observations were made in mature and hydrated C. arizonica pollen grains from various regions in Spain with different degrees of air pollution. Specimens were fixed using freezing protocols, and ultrathin sections were incubated with anti-rCup a 3 rabbit polyclonal antibodies. RESULTS: Labeling of Cup a 3 was detected in mature and hydrated C. arizonica pollen grains. It was more intense in pollen from polluted air regions, and abundant gold particles were observed as they were released through the pollen grain walls. Furthermore, gold particles remained abundant in the pollen cytoplasm. The labeling was noticeably lower in pollen grains from unpolluted air regions. CONCLUSIONS: Cup a 3 is present in the cytoplasm and walls of cypress pollen grains during the air dispersion and hydration stages. The abundance of Cup a 3 in pollen grains under polluted air conditions indicates that these cypresses intensify their activity as a defense from environmental pollution, thus strengthening their allergenicity. 相似文献