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991.
This case report describes a hairy B cell lymphoproliferative disorder (HBLD) with clinical and hematological features resembling hairy cell leukemia. The patient was a 29-year-old female who demonstrated atypical lymphocytes in her peripheral blood. Physical examination demonstrated splenomegaly, but there were no palpable superficial lymph nodes. Hematological examination showed a leukocyte count of 10.6 x 10(3)/mm3 with 41% atypical lymphocytes. Bone marrow examination showed a normal cellular and an atypical lymphocyte count of 42%. The atypical lymphocytes had microvilli and prominent membranous ruffles on their surfaces. Atypical lymphocytes expressed CD5- CD10- CD11c+ CD19+ CD20+ CD23- CD25- on the surface of the cells on examination by with a fluorescence activated cell sorter. Although these findings were similar to hairy cell leukemia, Japanese variant, the surface marker of the kappa chain and lambda chain was unbiased and studies of immunoglobulin gene rearrangements and expression showed polyclonal proliferation of B cells. Therefore, we diagnosed this patient as having HBLD. Because she did not demonstrate anemia or thrombocytopenia, she is not currently receiving medication. To date, the atypical lymphocyte count has not changed.  相似文献   
992.
993.
Tumor necrosis factor-alpha (TNF-alpha) is considered to be 1 of the factors that induce vasculitis, including coronary artery aneurysm (CA), in Kawasaki disease (KD), because the blood concentration of TNF-alpha is higher in patients with CA compared with those without. Therefore, an anti-TNF-alphaagent (infliximab) was administered to a 1-month-old girl with refractory KD complicated by CA and subsequently, the CA improved and KD was controlled without complications 20 months after the onset.  相似文献   
994.
Cytomegalovirus (CMV) disease is one of the major infectious complications after allogeneic hematopoietic stem cell transplantation (SCT). Several studies have shown that CMV-seropositive patients have a substantial survival disadvantage after bone marrow transplantation (BMT) or peripheral blood SCT (PBSCT). Between August 1998 and February 2006, 101 adult patients underwent myeloablative cord blood transplantation (CBT) from unrelated donors at our institution. Sixteen and 85 patients were CMV-seronegative and CMV-seropositive, respectively, prior to CBT. Outcomes of CBT were compared between CMV-seronegative and CMV-seropositive patients. The cumulative incidences of neutrophil engraftment at 60 d after CBT did not differ between CMV-seronegative and CMV-seropositive patients (100% and 94%, P = 0.09); however, the cumulative incidence of platelet engraftment at 100 d was higher in CMV-seronegative patients than CMV-seropositive patients (100% vs. 86%, P < 0.005). The cumulative incidence of CMV antigenemia at 100 d was lower in CMV-seronegative patients than CMV-seropositive patients (0% vs. 77%, P < 0.001); however, the cumulative incidences of CMV disease did not differ between CMV-seronegative and CMV-seropositive patients (0% vs. 1%, P = 0.84). The probabilities of disease-free survival at 2 yr also did not differ between CMV-seronegative and CMV-seropositive patients (92% vs. 72%, P = 0.16). The outcomes of CBT for CMV-seropositive patients as well as CMV-seronegative patients in our series were favorable. This might be due to effective antiviral therapy for CMV infection. Large-scale studies are needed to determine the impact of recipient CMV serostatus on the outcome of CBT for adults.  相似文献   
995.
Priming of cytotoxic T lymphocytes (CTLs) by dendritic cells (DCs) is crucial for elimination of pathogens and malignant cells. To activate CTLs, DCs present antigenic peptide-complexed MHC class I molecules (MHC-I) that will be recognized by the CTLs with T cell receptors and CD8 molecules. Here we show that paired Ig-like receptor (PIR)-B, an MHC-I receptor expressed on antigen-presenting cells, can regulate CTL triggering by blocking the access of CD8 molecules to MHC-I. PIR-B-deficient DCs evoked CTLs more efficiently, leading to accelerated graft and tumor rejection. PIR-B(+) non-DC transfectant cells served as less efficient stimulators and targets for CTLs than PIR-B(-) cells at the effector phase in vitro. On surface plasmon resonance analysis, PIR-B and CD8alpha alpha were revealed to compete in binding to MHC-I. Our results may provide a novel strategy for regulating CTL-mediated immunity and diseases in a sterical manner.  相似文献   
996.
An 18-year-old man with 4-year history of central diabetes insipidus and partial pituitary dysfunction was admitted to our hospital because of headache and nasal discharge. Magnetic resonance imaging (MRI) revealed abnormal mass in the sella turnica invading into the cavernous sinus and sinus maxillaries along with thickened tentorium cerebelli. Histopathology of the mass in the sinus maxillaries revealed spindle-shaped cells arranged in a fascicular pattern with varied myxoid and collagenized regions with various inflammatory cells. Immunostaining revealed the spindle-shaped cells were positive for smooth muscle actin. These features were identical to those of inflammatory myofibroblastic tumor (IMT). He was diagnosed with IMT in the sella turnica and other regions. Corticosteroid therapy improved clinical symptoms and follow-up MRI revealed amelioration of the thickened tentorium cerebelli. However, the other lesions were unchanged and pituitary dysfunction did not improve. Although rare, IMT should be considered in the differential diagnosis of a sellar mass. Early treatment with corticosteroid therapy may reduce the risk of disease progression.  相似文献   
997.
We report an autopsy case of elderly-onset anticentromere antibody-positive pulmonary-renal syndrome. An 84-year-old woman was admitted to our hospital with complaints of leg edema and general malaise. Neither skin rush nor arthritis was seen. Because of hematuria, proteinuria with various casts, renal dysfunction and anemia, a clinically diagnosis of rapidly progressive glomerulonephritis was made. Slight pulmonary hypertension was observed in ultrasonic cardiography. Hypocomplementemia was not seen. Tests for MPO- and PR 3-anti-neutrophil cytoplasmic antibodies and anti-glomerular basement membrane antibody were negative, but a high titer of antinuclear antibody with a discrete speckled pattern on immunofluorescent staining was disclosed. Results for anticentromere antibody and anti-Ki antibody were positive, but for anti-Sm antibody and anti-double stranded DNA antibody were both negative. She did not present any clinical features of systemic sclerosis or CREST syndrome. Subsequently, prednisolone was administered, but pulmonary alveolar hemorrhage occurred and the patient died of acute respiratory failure caused by massive pulmonary hemorrhage. Autopsy revealed crescentic glomerulonephritis including glomerular capillaritis and pulmonary capillaritis with positive granular deposits of immunoglobulins and compliment on the glomerular and pulmonary capillary walls. Immunologically mediated crescentic glomerulonephritis and pulmonary capillaritis was then diagnosed histopathologically. The main pathological feature of the case was small-vessel vasculitis with immune-complex deposition. Although this case did not fulfill the clinical criteria for systemic lupus erythematosus (SLE), its histological features resembled those of lupus nephritis and acute lupus pneumonitis. We speculated that anticentromere antibody-positive pulmonary-renal syndrome without any other symptoms or signs of connective tissue disease, such as our case, is a clinical entity distinct from typical SLE or CREST syndrome.  相似文献   
998.
The thrombotest (TT) technique has been widely used in Japan for monitoring oral anticoagulant therapy (OAT). The therapeutic range was originally recommended to be 10%–25%. However, the International Committee for Standardization in Hematology/International Committee on Thrombosis and Hemostasis (ICSH/ICTH) recommended using the international normalized ratio of prothrombin time (PT-INR) for monitoring OAT. It is necessary to use a universal standard measure for monitoring OAT in accordance with the ICSH/ISTH recommendation. We simultaneously measured TT and PT in blood samples from 1 157 patients on long-term warfarin therapy, and studied the correlation between TT and PT-INR. An excellent linear correlation was obtained between TT-INR and PT-INR with the regression equation PT-INR = 1.0420 TT-INR − 0.0987 (r = 0.905, P < 0.001). We also examined the correlation between the incidence of thromboembolism in 170 patients receiving warfarin therapy after prosthetic valve replacement; 50.5% received concomitant antiplatelet therapy. Thromboembolism occurred in 9 of 170 patients during a mean follow-up period of 2.44 years. The average TT values in patients with and without thromboembolism were 26.4% (PT-INR: 1.53) and 21.1% (1.73), respectively (P < 0.01). The incidence of thromboembolism did not differ significantly between patients on warfarin alone (average TT: 22.2%) and those on warfarin and antiplatelet agent (average TT: 20.9%). Our results suggest that the incidence of thromboembolism is low in Japan despite a less intensive regimen having been adopted. Received: June 22, 2000 / Accepted: October 4, 2000  相似文献   
999.
Background and objectives: The aim was to produce HBcAg from plants more cheaply than can be done by other currently available means, and to apply such antigen to immunoassay procedures for pretransfusion testing of donor blood. Materials and methods: Transgenic Nicotiana tabacum cv. SR-1 plants expressing the human hepatitis B virus (HBV) core antigen (HBcAg) gene were generated by Agrobacterium-mediated transformation. The recombinant product, called tHBcAg, can assemble itself into a spherical particle with a diameter of 25 to 30 nm, and can maintain two antigenic determinants of HBcAg, namely HBc/α and HBc/β. Partly purified tHBcAg was used in the hemagglutinationinhibition (HI) test, as routinely used by the Japanese Blood Center, to test a panel of 524 blood units taken from HBV-positive donors. Results: In the HI test, tHBcAg showed serologic properties comparable to that from Escherichia coli, the standard antigen used in the Japanese Blood Center. Conclusions: Transgenic plants can produce reagents for serologic testing and perhaps even such medical materials as oral vaccines.  相似文献   
1000.
K Akiyama  K Inoue  T Senshu 《Endocrinology》1989,125(3):1121-1127
We have performed an immunocytochemical study of peptidylarginine deiminase (EC 3.5.3.15) in rat pituitaries. Male and female rat pituitaries were fixed by brief transcardial perfusion of Bouin Hollande Sublimate solution. Immunoperoxidase staining of cryosections obtained from female pituitaries with an antiserum to rat skeletal muscle peptidylarginine deiminase yielded specific staining of numerous cells in the pars distalis. In contrast, few immunopositive cells were noted in the pars distalis of male pituitaries. At least some of the immunopositive cells in female pars distalis were also stained with an antiserum to rat PRL. No such coincidence of immunoreactivities was noted when antisera to other anterior pituitary hormones were used. Biochemical and immunocytochemical examination of peptidylarginine deiminase during the pregnant period revealed its marked depletion on day 7 and its substantial restoration on day 14, showing apparently negative correlation with the known changes in the secretory activities of lactotrophs. This and the female-dominant occurrence of peptidylarginine deiminase in lactotrophs suggest significant involvement of the enzyme in the function of lactotrophs.  相似文献   
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