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71.
Ambrozic A Avicin T Ichikawa K Kveder T Matsuura E Hojnik M Atsumi T Rozman B Koike T 《International immunology》2002,14(7):823-830
beta(2)-Glycoprotein I (beta(2)GPI) appears to be the major antigen for antiphospholipid antibodies (aPL) in patients with antiphospholipid syndrome (APS). In early infancy, virtually all children initiate transient immune response to non-pathogenic nutritional antigens, which fails to terminate in children with atopic diseases. To examine the possibility that a prolonged immune response to beta(2)GPI could also spread to the human protein, antibodies against human beta(2)GPI (anti-beta(2)GPI) were determined in 93 randomly selected children with different allergic diseases. A high frequency (42%) of IgG anti-beta(2)GPI was found in children with atopic dermatitis (AD), but not in those with other allergic diseases. Anti-beta(2)GPI in children with AD were exclusively of the IgG1 subclass and bound to bovine beta(2)GPI as well, but not to either beta(2)GPI combined with the phospholipid cardiolipin. The epitopes were identified in domain V of beta(2)GPI and the antibody binding was abolished upon the specific proteolytic cleavage of the phospholipid-binding C-terminal loop in domain V of beta(2)GPI. These results indicated that the epitopes for anti-beta(2)GPI in children with AD most likely resided in close vicinity of the phospholipid-binding site of beta(2)GPI. The epitopic difference from anti-beta(2)GPI in APS may explain presumed non-thrombogenicity of anti-beta(2)GPI in children with AD. 相似文献
72.
Resistance of Mice to Infection with Friend Disease Virus After Subcutaneous Injection of Friend Virus and Friend Spleen Cells
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C. L. Larson R. N. Ushijima S. K. Kasuga R. E. Baker M. B. Baker 《Infection and immunity》1973,8(5):708-714
Swiss mice injected subcutaneously with suspensions of spleen cells or an extract of spleens from mice infected with Friend virus develop resistance to subsequent intravenous inoculation of Friend virus. A single injection of either Friend virus or Friend cells induces resistance. Immunized mice display resistance when challenged 6 months after immunization and survive for at least 20 weeks after infection. Neutralization tests indicate that serum, but not lymphoid cells of resistant animals, can neutralize Friend virus. In vitro neutralization tests indicate that residence of virus within the peritoneal cavity of immune mice for 1 h sharply reduces the infective titer of the virus. 相似文献
73.
Noriko Kimura Mika Watanabe Tsuneo Ookuma Wakako Miura Takao Noshiro Yukio Miura Hiroshi Nagura 《Endocrine pathology》1994,5(3):178-182
Pheochromocytoma usually shows prominent nuclear atypia, but the presence of such atypical cells is known to be an unreliable
predictor of malignancy. DNA ploidy of pheochromocytomas has been analyzed by flow cytometry or photospectrometry on paraffinem-bedded
tissue, but the results were controversial. We performed DNA analysis on cytology specimens of 11 pheochromocytomas using
an image analysis system. All tumors had a mixed pattern of a large population of diploid cells and a small population of
polyploid cells. DNA content correlated with nuclear size, and larger cells had more DNA content. Such larger tumor cells
had polyploid nuclei, such as 4 C, 8 C, 16 C, and 32 C, in both malignant and benign pheochromocytomas. The larger polyploid
nuclei may result from difficulty of duplication at the mitotic phase of the cell cycle. 相似文献
74.
The authors report a case of Wegener's granulomatosis with the unusual manifestation of diffuse pulmonary hemorrhage. A 58-year-old man complained of bloody sputum and fever. Chest X-ray films showed multiple nodular shadows in both lung fields. He was diagnosed as having Wegener's granulomatosis by transbronchial lung biopsy, which revealed necrotizing granulomatous inflammation with necrotizing vasculitis. Despite treatment with cyclophosphamide and prednisolone, his condition rapidly deteriorated. An extensive diffuse alveolar shadow appeared in both lung fields in chest X-ray films, anemia became worse, and he died of respiratory failure. Autopsy revealed diffuse alveolar hemorrhage with necrotizing capillaritis in addition to the typical pathological findings in Wegener's granulomatosis. The capillaritis was characterized by neutrophilic infiltration of alveolar septa, and fibrin thrombi in alveolar capillaries. Diffuse pulmonary hemorrhage is uncommon in Wegener's granulomatosis. However, once diffuse pulmonary hemorrhage occurs, the respiratory condition rapidly deteriorates and is life-threatening. Therefore, accurate diagnosis and appropriate treatment are required. 相似文献
75.
Chikao Yutani Masami Imakita Hatsue Ishibashi-Ueda Michiaki Katsuragi Takao Yoshioka Takeyoshi Kunieda 《Pathology international》1993,43(3):135-141
Three cases of pulmonary hypertension caused by tumor emboli to the lungs are described. Two of the three cases had a clinical diagnosis of pulmonary thromboembolism until surgical embolectomy, and the other had a diagnosis of primary pulmonary hypertension. Autopsy disclosed chondrosarcoma, choriocarcinoma and gastric cancer as the primary tumors, respectively. Pulmonary vascular obstruction due to tumor embolism leading to pulmonary hypertension is a previously rare clinical entity, and obstructed pulmonary vessels are believed to tend to be small vessels. We compared the autopsy and radiological findings and concluded that pulmonary tumor embolism involved not only the small peripheral arteries but also the segmental and/or lobar arteries. 相似文献
76.
Hirano H Ezura Y Ishiyama N Yamaguchi M Nasu I Yoshida H Suzuki T Hosoi T Emi M 《Journal of human genetics》2003,48(6):288-292
Natural tooth loss represents a major medical issue within the elderly population, since it impairs masticatory function critical
for oral intake of essential nutrition. Contribution of genetic factors has been implicated in the determination of natural
tooth loss; degree of reduction in number of natural teeth remaining intact (NTI) varies among individuals; thus, heterogeneity
in NTI might reflect genetic variation within the population. One candidate gene, the matrix Gla protein gene (MGP), has been implicated in the pathogenesis of bone loss through a repression of bone/tooth formation. We have investigated
a possible association between the CA repeat polymorphism at the human MGP gene locus and the NTI in 458 elderly Japanese women. In 916 chromosomes tested, ten alleles of the polymorphic nucleotide
repeat were observed (designated A1–A10), among which five alleles were regarded as major alleles to be tested for the association.
Twenty-seven women who possessed an A6 allele (164 bp) had significantly higher NTI than the remaining participants (n=431), who did not carry an allele of that size (mean: 10.0 teeth vs 5.6 teeth; P=0.007, Mann-Whitney test). An eight-year longitudinal follow-up study of NTI suggested that the genetic variations at the MGP locus did not affect the rate of tooth loss in the elderly period. These results suggest that genetic variation at the MGP gene locus is associated with some determinants for tooth loss in elderly women. 相似文献
77.
Takao Shioya Hiroko Matsuda Akinori Noma 《Pflügers Archiv : European journal of physiology》1993,422(5):427-435
The present patch-clamp study shows that external Mg2+, Ca2+ and Sr2+ decrease the unit amplitude of inward current through the inward-rectifier K+ channel in a concentration-dependent manner. Sr2+ produces a voltage-dependent flickering block as well, and the fractional electrical distance between the external orifice and the Sr2+ binding site () is 0.73. The decrease of unit amplitude is reversible and voltage independent while it does not increase the noise level on the open-channel current. Unit current decreased by Mg2+ or Ca2+ has a longer mean open time, which is inversely proportional to the unit amplitude. External Mg2+ does not decrease the amplitude of unit outward current. A surface potential shift, measured using voltage-dependent Cs+ block (=1.60), failed to explain the current decrease. Therefore, we conclude that (1) the external divalent cations cause an extremely fast channel block, which appears as a decreased amplitude of the unit current on the recording system; (2) the blocking site (fast site) is present near the external orifice of the channel, and it is separate from the blocking site (slow site) to which Cs+ and Sr2+ bind. 相似文献
78.
An Epstein-Barr virus-producer line Akata: Establishment of the cell line and analysis of viral DNA 总被引:10,自引:0,他引:10
Kenzo Takada Kenichi Horinouchi Yasushi Ono Takao Aya Toyoro Osato Motoo Takahashi Shinichi Hayasaka 《Virus genes》1991,5(2):147-156
An Epstein-Barr virus (EBV)-producer line, designated Akata, was established from a Japanese patient with Burkitt's lymphoma. The Akata line possessed the Burkitt's-type chromosome translocation, t(8q-; 14q+), and was derived from the tumor cell. Akata cells produced a large quantity of transforming virus upon treatment of cells with anti-immunoglobulin antibodies (Takada, 1984). Southern blot analysis of viral DNA indicated that the Akata EBV is nondefective and more representative of wild-type viruses. Akata cells should be useful as a source of EBV. 相似文献
79.
Fibrinogen stabilizes placental-maternal attachment during embryonic development in the mouse 总被引:9,自引:0,他引:9
Iwaki T Sandoval-Cooper MJ Paiva M Kobayashi T Ploplis VA Castellino FJ 《The American journal of pathology》2002,160(3):1021-1034
In humans, maternal fibrinogen (Fg) is required to support pregnancies by maintaining hemostatic balance and stabilizing uteroplacental attachment at the fibrinoid layer found at the fetal-maternal junction. To examine relationships between low Fg levels and early fetal loss, a genetic model of afibrinogenemia was developed. Pregnant mice homozygous for a deletion of the Fg-gamma chain, which results in a total Fg deficiency state (FG(-/-)), aborted the fetuses at the equivalent gestational stage seen in humans. Results obtained from timed matings of FG(-/-) mice showed that vaginal bleeding was initiated as early as embryonic day (E)6 to 7, a critical stage for maternal-fetal vascular development. The condition of afibrinogenemia retarded embryo-placental development, and consistently led to abortion and maternal death at E9.75. Lack of Fg did not alter the extent or distribution pattern of other putative factors of embryo-placental attachment, including laminin, fibronectin, and Factor XIII, indicating that the presence of fibrin(ogen) is required to confer sufficient stability at the placental-decidual interface. The results of these studies demonstrate that maternal Fg plays a critical role in maintenance of pregnancy in mice, both by supporting proper development of fetal-maternal vascular communication and stabilization of embryo implantation. 相似文献
80.
Aoki Y Saida T Nakano I Saito T Ikeguchi K Urabe T Nishiguchi E Suzuki H Takahashi K Mizuno Y 《Rinsho byori. The Japanese journal of clinical pathology》2002,50(3):308-312
Medullasin levels in granulocytes of patients with neurological diseases and healthy volunteers were determined by the enzyme immunoassay using mouse monoclonal antibodies against human medullasin and o-phenylenediamine-H2O2 as the detection system of the enzyme activity. One hundred twenty-one out of 159 patients with multiple sclerosis (76.1%) showed positive results (above means of normals + 2SD) in this test, while only 16.9% (24/142) of patients with non-inflammatory neurological diseases had positive results. This enzyme immunoassay method for medullasin is considered to be an useful paraclinical test for the diagnosis of multiple sclerosis. 相似文献