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991.
Geetika Singh Mehar Chand Sharma Vaishali Suri Chitra Sarkar Ajay Garg Manmohan Singh 《Annals of diagnostic pathology》2013,17(3):276-280
Alveolar soft part sarcoma (ASPS) is a relatively rare tumor that mostly presents as a slow growing mass in the deep soft tissue of the extremities. A substantial number of cases in children occur in the head and neck region; however, in any age group, it is very rarely reported in the sinonasal region. We report a case of ASPS of the paranasal sinuses with sellar extension in a 25-year-old man that masqueraded as a giant invasive pituitary adenoma. This is only the fifth case of sinonasal ASPS in literature. The clinical and radiological diagnoses were misleading, but an extensive pathology workup including electron microscopy helped reach an accurate diagnosis in this unusual case. 相似文献
992.
Ultraviolet irradiation inhibits alloreactive and mitogen-induced responses and might reduce both graft-versus-host and host-versus-graft reactions after bone marrow transplantation (BMT). We have studied proliferative responses to mitogens and reactivity in mixed lymphocyte culture after irradiation with ultraviolet (UV)-B light using splenocytes from Balb/c (H-2d) and CBA (H-2k) mice. Response to mitogens and in MLC was strongly inhibited by 20 J/m2 and abolished at 50 J/m2. Clonogenic cell recovery (CFU-GM; CFU-S) after UV-B irradiation was also reduced. When bone marrow and spleen cells were transplanted from parent (Balb/c) animals into F1 hybrid (Balb/c X CBA) recipients, all animals died with features indicative of graft-versus- host disease (GVHD) in 34 days. If the grafts were first irradiated with 100 J/m2 of UV-B at a mean wavelength of 310 nm, then 76% survived to day 80 when they were killed and shown to have normal marrow cellularity. The remainder died in marrow aplasia or of GVHD. H-2 typing in a group of surviving recipients showed either donor hematopoiesis only (8 of 15), mixed allogeneic chimerism (5 of 15), or recipient type hematopoiesis (2 of 15). Higher doses (200 to 300 J/m2) were detrimental to survival with 88% of recipients dying in marrow aplasia. Syngeneic BMT in Balb/c mice showed slower hematopoietic reconstitution when the grafts were first irradiated with 100 J/m2. After BMT from Balb/c to CBA mice all recipients of unirradiated grafts died within 54 days. By contrast, after graft irradiation with 100 J/m2 survival of recipient animals to day 80 was 59%. If these grafts were treated with 50 J/m2 survival was only 26% with an increase in deaths due to GVHD. Hematopoiesis at day 80 in a group of survivors studied by Ig heavy chain allotyping indicated donor type hematopoiesis in 6 of 10 (50 J/m2) and 2 of 9 (100 J/m2). These data indicate that UV-B irradiation inhibits lymphocyte reactivity and can prevent GVHD. However, there is clear in vitro and in vivo evidence of stem cell damage, such that autologous marrow recovery was demonstrated in a proportion of recipients. In parent----F1 UV-irradiated transplants, sustained hematopoietic recovery was effected in the majority by donor stem cells. 相似文献
993.
Donaldson VH; Wagner CJ; Tsuei B; Kindness G; Bing DH; Harrison RA; Rosen FS 《Blood》1987,69(4):1096-1101
Purified preparations of normal C1(-)-inhibitor (C1(-)-INH) formed high mol wt complexes with plasma kallikrein that were stable during sodium dodecyl sulfate (SDS)-gel electrophoresis, but most of the dysfunctional C1(-)-INH proteins isolated from plasma of patients with type II hereditary angioneurotic edema (HANE) did not. Two of eight dysfunctional C1(-)-INH proteins were cleaved to lower mol wt forms that were not seen following the reaction of normal C1(-)-INH with equimolar amounts, or less, of plasma kallikrein. Only the higher mol wt component of normal C1(-)-INH (106,000 mol wt) appeared to form a stable complex with the plasma kallikrein, whereas both the 106,000 and 96,000 mol wt forms made stable complexes with C1-s. When a preparation of normal C1(-)-INH containing a homogeneous single band of C1(-)-INH was exposed to C1-s or kallikrein, a "doublet" form evolved in which the heaviest band was in the original position of native C1(-)-INH; C1- s cleavage provided a second band of 96,000; and cleavage by kallikrein, a second band of 94,000 mol wt. We conclude that dysfunctional C1(-)-INH proteins from plasma of persons with type II hereditary angioneurotic edema have impaired interactions with plasma kallikrein and are heterogeneous with respect to these interactions. Moreover, the requirements for the formation of stable complexes between normal C1(-)-INH and plasma kallikrein differed from those for stable complex formation with C1-s. The doublet form of C1(-)-INH, which purified preparations frequently demonstrate, may be due to prior cleavage by C1-s or kallikrein. 相似文献
994.
Diwan Chand Hamed K. El-Aguizy R.D. Richards Shambhu D. Varma 《Experimental eye research》1982,35(5):491-497
The rat lens, when cultured in medium 199 containing 55·5 mm-glucose and 15% fetal calf serum, developed a visible equatorial cortical opacity by the 96th hour. The gerbil lens, whose aldose reductase activity was twice that of the rat lens, developed such an opacity after 24 hr. The development of opacity is thus faster in a lens with higher aldose reductase activity. The relation of aldose reductase with genesis of sugar cataracts is also evident from the observation that substitution of glucose by xylose accelerated cataract formation. Xylose is known to have lower Km for aldose reductase than glucose. Fortification of the media with vitamin E (2·4 μm) or GSH (0·1 mm) did not prevent the cataract development. The level of lens malonaldehyde, one of the products of lipid peroxidation, was also unaffected either following culture in high sugar media or following in vivo induction of diabetes by streptozotocin. The oxidative stress, thus, does not seem to be involved in initiating the formation of sugar cataracts. 相似文献
995.
Expression of integrins and examination of their adhesive function in normal and leukemic hematopoietic cells 总被引:8,自引:0,他引:8
Adhesion of hematopoietic progenitor cells to marrow-derived adherent cells has been noted for erythroid, myeloid, and lymphoid precursors. In this report, we have characterized very late antigen (VLA) integrin expression on normal CD34+ marrow progenitors, on leukemic cell lines, and on blasts from patients with acute myelogenous or monocytic leukemias. CD34+ progenitor cells expressed the integrin beta 1 chain (CD29), VLA-4 alpha (CD49d), and VLA-5 alpha (CD49e). The myeloid lines KG1 and KG1a also expressed CD49d and CD49e as did the Mo7e megakaryoblastic line. CD29, CD18, and CD11a were also present on each of these cell lines. Only the Mo7e line expressed the cytoadhesins GPIIbIIIa or GPIb. Binding of KG1a to marrow stroma was partially inhibited by antibodies to CD49d and its ligand, vascular cell adhesion molecule (VCAM-1). The majority of leukemic blasts studied expressed CD49d and CD49e as well. Blasts from patients with acute myelomonocytic leukemia consistently bound to stroma at levels greater than 20%, and adhesion to stroma could in some cases be partly inhibited by anti- CD49d. No role for glycosylphosphatidyl-inositol (GPI)-linked structures was demonstrated in these binding assays because the adhesion of leukemic blasts to stroma was not diminished after treatment with phosphatidylinositol-specific phospholipase C (PI-PLC). These studies indicate that CD34+ myeloid progenitors, myeloid leukemic cell lines, and leukemic blasts possess a similar array of VLA integrins. Their functional importance individually or in combination with other mediators of attachment in adhesion, transendothelial migration, and differentiation has yet to be fully elucidated. 相似文献
996.
DH Buchholz ; JE Squires ; JH Herman ; AT Ng ; JK Anderson ; SL Hedberg 《Transfusion》1997,37(7):715-718
BACKGROUND: Increases in the use of single-donor apheresis components have increased the need for platelet donors. In the United States, persons must weigh 110 pounds or more to qualify as blood donors, and the same weight limitation has been placed on apheresis donors. Because automated plateletpheresis with some instruments differs considerably from whole-blood donation with respect to the volume of blood removed from the donor, the feasibility of using persons weighing between 90 and 110 pounds as platelet donors was evaluated by the use of the CS- 3000 blood cell separator. STUDY DESIGN AND METHODS: The study was performed using female subjects who met all usual donor requirements except for minimum weight. The standard platelet collection procedure of the instrument was used, except that the blood processing rate was manually selected so as to optimize the blood withdrawal and return rate in individuals. Vital signs were recorded before and after donation as were signs or symptoms of any type of donor reaction. RESULTS: Twenty-six of 28 women completed the donation procedure; in two instances, collection was terminated prematurely because of an inability to maintain adequate venous access. An average of 4.5 × 10(11) platelets were collected during a mean donation time of 110 minutes. All donors tolerated the procedure well, and no serious adverse reactions were seen. Because of the administration of priming solution and anticoagulant during apheresis, there was a net positive fluid balance following the procedure, in spite of the removal of approximately 220 mL of platelet concentrate. CONCLUSION: These preliminary studies suggest that 90- to 110-pound persons may serve as plateletpheresis donors. Additional studies are needed to more fully document the safety and efficacy of this approach. The use of lower- weight donors may significantly increase the number of persons available to provide single-donor platelet components. 相似文献
997.
Supriya Mallick Ahitagni Biswas Narender Kumar Mehar Chand Sharma Rakesh Kumar Rama Mohan Reddy Pramod Kumar Julka Goura Kishore Rath 《Neurologia i neurochirurgia polska》2012,46(5):489-495
Primary intracranial squamous cell carcinoma is extremely rare, with most cases arising from malignant transformation of dysembryogenetic lesions such as epidermoid and dermoid cysts. Intracranial squamous cell neoplasm arising de novo is even rarer and has been reported in only four patients to date. We herein describe a case of primary intracranial squamous cell carcinoma arising de novo in the right frontal lobe in a 35-year-old woman treated with a combination of surgery and postoperative conformal radiation. We have also shed light on the biology and the therapeutic options of this enigmatic tumour. 相似文献
998.
Puneet Jain Praveen Kishore Jasjit Singh Bhasin Subhash Chand Arya 《Annals of Indian Academy of Neurology》2015,18(2):233-234
Basal ganglia stroke is known following trivial head trauma. Recently a distinct clinic-radiological entity termed ‘mineralizing angiopathy’ was described. We report an infant who developed basal ganglia stroke following trivial fall. His clinic-radiological features are described. 相似文献
999.
Heterogeneous expression of Epstein-Barr virus latent proteins in endemic Burkitt's lymphoma 总被引:3,自引:1,他引:3
Niedobitek G; Agathanggelou A; Rowe M; Jones EL; Jones DB; Turyaguma P; Oryema J; Wright DH; Young LS 《Blood》1995,86(2):659-665
Epstein-Barr virus (EBV)-infected cells may sustain three distinct forms of virus latency. In lymphoblastoid cell lines, six EBV-encoded nuclear antigens (EBNA1, 2, 3A, 3B, 3C, -LP), three latent membrane proteins (LMP1, 2A, 2B), and two nuclear RNAs (EBERs) are expressed. This form of latency, termed latency III, is also encountered in some posttransplant lymphoproliferative disorders. In EBV-positive cases of Hodgkin's disease, the EBERs, EBNA1, and the LMPs are expressed (latency II), whereas in Burkitt's lymphoma (BL) only the EBERs and EBNA1 have been detected (latency I). We have studied the expression of EBV proteins in 17 cases of EBV-positive endemic BL by immunohistology. Expression of LMP1 was seen in variable proportions of tumor cells in two cases and EBNA2 was detected in some tumor cells in three other cases. Also, the BZLF1 trans-activator protein was expressed in a few tumor cells in 6 cases, indicating entry into the lytic cycle. A phenotypic drift from latency I to latency III has been observed previously in some BL cell lines. Our results suggest that a similar phenomenon may occur in BL in vivo and indicate that the operational definition of EBV latencies is not easily applied to human tumors. 相似文献
1000.
Kamales Kumar Saha Mandar Deval Pankaj Manoria Prabhash Chand Manoria Lukash Jagdale 《Indian Journal of Thoracic and Cardiovascular Surgery》2011,27(4):165-168