Chemo- and radio-protective effects of polysaccharide of Spirulina platensis on hemopoietic system of mice and dogs.
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AIM: To observe polysaccharide of Spirulina platensis (PSp) on the hematopoietic system of mouse and dogs which were damaged by injection of cyclophosphamide (CTX) and 60Co-gamma irradiation. METHODS: CTX and 60Co gamma ray were used to induce bone marrow damage, and the experimental animals were ig with different dose of PSp in vivo, after 12-d and 21-d administration, the whole blood cells and nucleated cells in bone marrow were measured, and the DNA in bone marrow were inspected by UV-spectrophotometer. RESULTS: CTX and 60Co-gamma irradiation induced hemopoietic system damage in mice and dogs, respectively. PSp 30, 60 mg/kg increased the level of the white cells in blood and nucleated cells and DNA in bone marrow in mice but had no effects on red cells and hemoglobins. PSp 12 mg/kg increased the level of red cells, white cells, and hemoglobins in blood and nucleated cells in bone marrow in dogs (P < 0.01), and the effects of PSp 60 mg/kg were better than that of berbamine hydrochloride 60 mg/kg. CONCLUSION: PSp has chemo-protective and radio-protective capability, and may be a potential adjunct to cancer therapy. (+info)
Non-Hodgkin's malignant lymphomata of upper digestive and respiratory tract: natural history and results of radiotherapy.
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A total of 218 non-Hodgkin's malignant lymphomata of the upper digestive and respiratory tract are reported. 72% had Waldeyer's ring involvement and 22% had paranasal sinus involvement. Ilio-lumbar lymphography was performed in 98 cases: 33 lymphograms were abnormal. In 152 Stage I and II patients, loco-regional irradiation gave 129 remissions. Among these patients, 66 suffered a relapse, most of them during the first year after treatment. Primary relapse analysis revealed 18 true recurrences, 10 nodal extensions and 38 extranodal disseminations. The median survival is 14 months for all stages; the survival rate at 5 years is 38% for Stages I and II for patients treated by 60Co alone. No statistical significance in prognosis has been found for age, sex, size of primary tumour, involvement of upper or lower nodes in the neck, histological type nor between Stage I and Stage II. Lymphography and x-ray gastrointestinal examination must be performed routinely before treatment in order to stage patients correctly. (+info)
Primary hemangioma of the occipital bone in the region of the torcula--two case reports.
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Two rare cases of subtorcular occipital bone hemangioma occurred in 26-year-old and 30-year-old female patients. Partial resection was performed in both cases because of the proximity to the torcula. No recurrence was seen at follow-up examination at 9 and 12 months. (+info)
An activity quantification method based on registration of CT and whole-body scintillation camera images, with application to 131I.
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This article presents a new method for conjugate view activity quantification for 131I-labeled monoclonal antibody distribution. METHODS: The method is based on the combined use of images from 3 modalities: whole-body (WB) scintillation camera scanning, WB transmission scanning using 57Co, and CT. All images are coaligned using a recently developed program for the registration of WB images. Corrections for attenuation, scatter, and septal penetration are performed in image space. Compensation for scatter and septal penetration is performed by deconvolution, using point-response functions determined from Monte Carlo simulations. Attenuation correction is performed by applying a patient-specific 364-keV narrow-beam attenuation map obtained by combining information from the CT and the transmission scan. A relationship is presented for the conversion of the CT numbers to mass density. The attenuation- and scatter-compensated image is converted from counts to activity using a sensitivity value that was determined for 364-keV photons in air. This activity projection image is then analyzed for the activity of volumes of interest (VOI) using 2-dimensional regions of interest (ROIs) that are determined from the CT study. The CT is first resliced into coronal slices, and a maximum-extension ROI is outlined that encloses the VOI. Compensation for background activity and overlapping organs is performed on the basis of total patient thickness in the projection line, and on precalculated organ- background thickness fractions. RESULTS: Method evaluation was performed using data from both experimental measurements and Monte Carlo simulations. The use of an attenuation map derived directly from the CT study was also evaluated. For organ activity quantification, an accuracy of > or =10% was obtained. For small-diameter tumors, deviations were larger because of lack of correction for the background-dependent partial-volume effect. CONCLUSION: Registration of CT and WB scintillation camera images was successfully applied to improve activity quantification by the conjugate view method. (+info)
Changes in immunoferritin labeling of Rickettsia tsutsugamushi after serial cultivation in 60Co-irradiated BHK cells.
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The immunolabeling characteristics of Rickettsia tsutsugamushi (Gilliam strain) were examined by using a purified immunoglobulin G fraction of antibody to R. tsutsugamushi raised in rabbits. Formalin-fixed rickettsiae were reacted with this antibody and then with ferritin-conjugated goat anti-rabbit Fc antibody. R. tsutsugamushi cultivated in yolk sacs was used to raise antibody for this study. When rickettsiae in BHK-21 cells infected from yolk sac seed material were immunoferritin labeled, the binding of ferritin was found to be dense and uniform on the outer surface of the rickettsiae in disrupted host cells. Immunolabeling of purified suspensions of extracellular rickettsiae resulted in the uniform ferritin labeling of the microorganism. Aggregation of these rickettsiae by antibody appeared to depend upon the purity of the pellets. Immunoferritin labeling examined at high magnification revealed ferritin very close to the outer dense leaflet of the outer membrane. On some rickettsiae or on focal sites of others, the labelin; was several ferritin particles thick, suggesting the presence of a thick coating. The immunoferritin labeling of R. tsutsugamushi during successive serial passages in BHK-21 cells revealed decreased labeling with each passage, and by the 10th passage there was no detectable labeling. However, these rickettsiae inoculated back into yolk sacs regained their immunoferritin labeling. R. tsutsugamushi passed back into yolk sacs after four serial propagations in BHK-21 cells regained their labeling on the first passage in yolk sacs. However, rickettsiae from the 20th serial passage in BHK-21 cells required five passages in yolk sacs to reestablish their previous labeling affinity. Rickettsiae which did not label after 20 passages in BHK cells regained some of their labeling characteristics when sonicated. Antibody against rickettsiae cultivated in BHK-21 cells continued labeling rickettsiae even after 9 serial passages in BHK-21 cells. (+info)
Kit signaling inhibits the sphingomyelin-ceramide pathway through PLC gamma 1: implication in stem cell factor radioprotective effect.
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Previous studies demonstrated that Kit activation confers radioprotection. However, the mechanism by which Kit signaling interferes with cellular response to ionizing radiation (IR) has not been firmly established. Based on the role of the sphingomyelin (SM) cycle apoptotic pathway in IR-induced apoptosis, we hypothesized that one of the Kit signaling components might inhibit IR-induced ceramide production or ceramide-induced apoptosis. Results show that, in both Ba/F3 and 32D murine cell lines transfected with wild-type c-kit, stem cell factor (SCF) stimulation resulted in a significant reduction of IR-induced apoptosis and cytotoxicity, whereas DNA repair remained unaffected. Moreover, SCF stimulation inhibited IR-induced neutral sphingomyelinase (N-SMase) stimulation and ceramide production. The SCF inhibitory effect on SM cycle was not influenced by wortmannin, a phosphoinositide-3 kinase (PI3K) inhibitor. The SCF protective effect was maintained in 32D-KitYF719 cells in which the PI3K/Akt signaling pathway is abolished due to mutation in Kit docking site for PI3K. In contrast, phospholipase C gamma (PLC gamma) inhibition by U73122 totally restored IR-induced N-SMase stimulation, ceramide production, and apoptosis in Kit-activated cells. Moreover, SCF did not protect 32D-KitYF728 cells (lacking a functional docking site for PLC gamma 1), from IR-induced SM cycle. Finally, SCF-induced radioprotection of human CD34(+) bone marrow cells was also inhibited by U73122. Altogether, these results suggest that SCF radioprotection is due to PLC gamma 1-dependent negative regulation of IR-induced N-SMase stimulation. Beyond the scope of Kit-expressing cells, it suggests that PLC gamma 1 status could greatly influence the post-DNA damage cellular response to IR, and perhaps, to other genotoxic agents. (+info)
Improved body-outline imaging technique for localization of sentinel lymph nodes in breast surgery.
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Many centers use techniques for localizing the sentinel lymph node (SLN) associated with a breast tumor. Protocols involve the use of an intraoperative probe and blue dye but may or may not include scintigraphy. METHODS: Three methods of body-outline imaging were investigated to aid SLN localization. Body outlines were acquired using a handheld source; a transmission image was acquired from a (57)Co-flood source; and, finally, a new method is described using a (153)Gd-line source attenuation correction for body outline. RESULTS: Method 1 images were of low quality, although 83% of SLNs were visualized. Body outline was unsatisfactory for surgical localization. Method 2 was unsatisfactory because of the lack of a lateral image. Method 3 enabled good presurgical visualization of the SLN (73%) and speeded surgical localization. CONCLUSION: The (153)Gd-line source consistently gives optimal-quality body-outline images. This source is simple, quick, and clearly locates the SLN on multiple projections. (+info)
Management of generalized malignant lymphomata with "systemic" radiotherapy.
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The natural history of lymphocytic lymphomata is such that anatomical generalization of disease is usually present at the time of diagnosis. Tumour infiltration of extralymphatic sites such as the liver and bone marrow is identifiable with particular frequency in those cases presenting with lymph node manifestations of disease. Even in the absence of detectable extralymphatic dissemination, the lymphatic involvement is often sufficiently diffuse to mitigate against extensive lymph node irradiation "a la Hodgkin's disease" as appropriate or technically feasible form of treatment. Rather, systemic treatment must be recognized as imperative for the majority of newly diagnosed patients and we have investigated "systemic" radiotherapy as an alternative to chemotherapy during the past decade. Our experience with 57 consecutive patients with lymphocytic lymphoma has been reviewed. Total body irradiation (TBI) has been found to yield high remission rates despite a lack of serious toxicity or constitutional reactions. Rigorous diagnostic staging was not employed but despite the advanced stage of disease which was clinically obvious in most cases, survival rates have been strikingly high. Actuarially calculated 5-year survival rates for the well differentiated (diffuse and nodular combined), nodular poorly differentiated and diffuse poorly differentiated subtypes are 85%, 69% and 51% respectively. Furthermore, initial management with radio-therapy as described has not negated with effective use of subsequent chemotherapy when selectively required. (+info)