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Activation and expansion in culture with rIL-2 of peripheral blood (PB) and/or bone marrow (BM) specimens derived from children with ALL and ANLL, with active disease (AP) and in remission were studied (RP). Baseline NK cytolytic activity from AP was found to be depressed, whereas RP-derived cells had normal NK activity, as assayed against K562 targets. Culture in rIL-2 significantly enhanced the NK activity of both AP- and RP-derived cells and generated LAK activity, as assayed by 4-hour 51Cr release, against NK-resistant Raji cell line and against fresh, allogeneic, and autologous tumor cells. Lytic activity against fresh, cryopreserved leukemia blasts was of lower than that found against cell lines. In three patients higher lytic activity against autologous than against allogeneic blasts was demonstrated. Expansion in culture with rIL-2 varied from twofold to 120-fold. rIL-2 activation and expansion was better in RP than in AP. The predominant phenotype of activated cells, as determined by flow cytometry, was [mean % (SD)]: CD3- = 54 (12), CD8+ = 55 (17), and NKH1+ = 26 (7). The consistently high level of CD8+ cells was accompanied by very low levels of CD4+ cells: mean = 11% (14). Double-marker analysis showed mean of 33% (10) for CD3+/NKH1+ cells and mean = 32 (11) for CD8+/NKH1+ cells, implying that these populations were overlapping. Kinetics of expression of cell surface markers during 2 to 3 weeks in culture showed that CD8+ and NKH1+ enrichment occurred during the first week and lasted for up to 4 weeks, whereas CD4+ expression decreased after the second week. A significant decrease in the expression of IL-2 receptors (CD25) was observed from the second week of culture. This study shows the feasibility of in vitro generation of killer cells from PB and BM of pediatric leukemia patients. 相似文献
33.
Zhou X Gunderson BD Olson WH;Gem DR ICD Clinical Worldwide Investigators 《Journal of cardiovascular electrophysiology》2004,15(1):14-20
INTRODUCTION: Nonsustained ventricular tachycardia (NSVT) is a frequent phenomenon in some patients with heart disease, but its association with sustained ventricular tachycardias (ventricular tachycardia [VT]/ventricular fibrillation [VF]) is still not clear. The aim of this study was to determine whether NSVT incidence was associated with sustained VT/VF in patients with an implantable cardioverter defibrillator (ICD). METHODS AND RESULTS: Retrospective data analysis was conducted in 923 ICD patients with a mean follow-up of 4 months. NSVT and sustained VT/VF were defined as device-detected tachycardias. The incidence rates of NSVT and sustained VT/VF as well as ICD therapies were determined as episodes per patient. The NSVT index was defined as the product of NSVT episodes/day times the mean number of beats per episode, i.e., total beats/day. The NSVT index peak was defined as the highest value on or prior to the day with sustained VT/VF episodes. Patients (n = 393) with NSVT experienced a higher incidence of sustained VT/VF (17.2 +/- 63.0 episodes/patient) and ICD therapies (15.2 +/- 61.4 episodes/patient) than patients (n = 530) without NSVT (sustained VT/VF: 0.5 +/- 6.6 and therapies: 0.5 +/- 5.6; P < 0.0001). Approximately 74% of NSVT index peaks occurred on the same day or <3 days prior to sustained VT/VF episodes. The index was higher for peaks < or =3 days prior to the day with sustained VT/VF (94.3 +/- 140.1 total beats/day) than for peaks >3 days prior to the day with sustained VT/VF (32.7 +/- 55.9 total beats/day; P < 0.0001). CONCLUSION: ICD patients with NSVT represent a population more likely to experience sustained VT/VF episodes with a temporal association between an NSVT surge and sustained VT/VF occurrence. 相似文献
34.
Nanthakumar K Paquette M Newman D Deno DC Malden L Gunderson B Gilkerson J Greene M Heng D Dorian P 《American heart journal》2000,139(5):797-803
BACKGROUND: Inappropriate therapy from supraventricular tachyarrhythmias (atrial fibrillation [AF] and sinus tachycardia [ST]) in patients with implanted cardioverter defibrillators is a major challenge. We tested the performance of stability algorithms from 3 manufacturers for episodes of inappropriate therapy delivered because of AF and an onset algorithm for all episodes of inappropriate therapy caused by ST. METHODS: Therapy was classified as caused by ventricular tachycardia (VT), ST, or AF from review of stored intracardiac electrograms, history, clinical information, and R-R data before study inception. By using 30 to 60 R-R intervals before therapy, sensitivity and specificity for a family of stability values and percentage of onset values were calculated for each manufacturer and receiver operating characteristic curves generated. RESULTS: Of the 217 patients monitored, 62 (29%) received inappropriate therapy, and 40 had complete R-R information available. Of the 40 patients, 21 patients received therapy for AF, 19 for ST, and 1 patient for noise; 15 (38%) also received appropriate therapy for VT. We analyzed 83 episodes of VT from 18 patients, 94 episodes of AF from 21 patients, and 56 episodes of ST from 19 patients. Specificity, in the clinically relevant sensitivity range of >/=95%, was comparable across manufacturers at about 40%. An onset value of 80% was associated with 91% sensitivity and 95% specificity for the specific algorithm tested. CONCLUSIONS: Inappropriate therapy is a common problem in implantable cardiac defibrillators. The performance of the stability algorithms used to differentiate AF from VT was less than ideal, though comparable across manufacturers. The onset algorithm accurately differentiates ST from VT. 相似文献
35.
Dr. Ricardo N. Goes M.D. Dr. Robert W. Beart Jr. M.D. Anthony J. Simons M.D. Leonard L. Gunderson M.D. Dr. Gordon Grado M.D. Oscar Streeter M.D. 《Diseases of the colon and rectum》1997,40(10):1177-1179
PURPOSE: Locally recurrent rectal cancer is associated with poor quality of life and has justified aggressive surgical and adjuvant approaches to control the disease. This study was designed to evaluate if the use of brachytherapy in association with wide surgical excision (debulking operation) can offer reasonable palliation for patients with locally recurrent rectal cancer. MATERIALS AND METHODS: Patients with biopsy-proven locally recurrent rectal cancer who were not candidates for intraoperative radiation therapy and who were previously considered as having unresectable tumors were included in the study and were followed-up from May 1981 to November 1990. All of them had undergone laparotomy and had either radical or debulking surgical resection performed. At the same time, brachytherapy was used with temporary or permanent implant of seeds of iridium-192 or iodine-125. RESULTS: Thirty patients were included. Patients ranged in age from 28 to 74 years, and 16 patients were female. No mortality was observed, and morbidity was low (small-bowel obstruction (1 patient), intestinal fistula (1 patient), and urinary fistula (1 patient). Histologic examination of the specimen showed gross residual disease in 67 percent of patients and microscopic disease in 25 percent of patients. Long-term follow-up was possible in 28 patients. Mean follow-up and local control were, respectively, 26.5 months and 37.5 percent for gross residual disease and 34 months and 66 percent for microscopic residual disease. Eighteen patients (64 percent) had locally recurrent rectal cancer under control at the time of the last follow-up, with seven patients (25 percent) having no evidence of local or distant recurrence. CONCLUSION: This is the first report of brachytherapy for locally recurrent rectal cancer. This appears to offer a therapeutic alternative to patients who are not candidates for intraoperative radiation therapy. Surgical morbidity and mortality are acceptable. Local control in 18 patients (64 percent) is comparable with intraoperative radiation therapy or more morbid surgical alternatives. Cancer-related deaths are most often related to disseminated disease, which suggests the need for systemic therapy in addition to brachytherapy. 相似文献
36.
Immunologic status of hemophilia patients treated with cryoprecipitate or lyophilized concentrate 总被引:1,自引:0,他引:1
We evaluated 37 patients with moderate or severe hemophilia A and six patients with severe factor IX deficiency for clinical or laboratory evidence of immune abnormalities. Patients were assigned to one of four groups according to the type of clotting factor replacement. Twenty patients had received only cryoprecipitate during the two years preceding the evaluation (group I); 11 additional patients were treated predominantly with cryoprecipitate but had also received up to nine bottles of factor VIII concentrate (group II); six patients received factor VIII concentrate (group III); six patients received factor IX concentrate (group IV). There was no clinical or laboratory evidence of immunodeficiency among the 43 patients. The mean absolute number of Th cells was normal in all patient groups, but the mean absolute number of Ts cells was increased compared with controls, both in patients treated with cryoprecipitate and in patients treated with factor VIII or factor IX concentrate. There was no correlation between the Th/Ts ratio and patient age, alanine aminotransferase level, hepatitis serology, in vitro lymphocyte function, or amount of clotting factor administered. Our observations demonstrate that the volunteer or commercial origin of clotting factor replacement cannot fully explain the alterations in lymphocyte subset distribution previously described in patients with hemophilia A. 相似文献
37.
RD Vaithilingam SH Safii NA Baharuddin LP Karen‐Ng R Saub F Ariffin H Ramli A Sharifuddin MFH Hidayat R Raman YK Chan NA Rani RA Rahim N Shahruddin SC Cheong PM Bartold RB Zain 《Oral diseases》2015,21(1):e62-e69
Periodontal bio‐repositories, which allow banking of clinically validated human data and biological samples, provide an opportunity to derive biomarkers for periodontal diagnosis, prognosis and therapeutic activities which are expected to improve patient management. This article presents the establishing of the Malaysian Periodontal Database and Biobank System (MPDBS) which was initiated in 2011 with the aim to facilitate periodontal research. Partnerships were established with collaborating centres. Policies on specimen access, authorship and acknowledgement policies were agreed upon by all participating centres before the initiation of the periodontal biobank. Ethical approval for the collection of samples and data were obtained from institutional ethics review boards. A broad‐based approach for informed consent was used, which covered areas related to quality of life impacts, genetics and molecular aspects of periodontal disease. Sample collection and processing was performed using a standardized protocol. Biobanking resources such as equipment and freezers were shared with the Malaysian Oral Cancer Database and Tissue Bank System (MOCDTBS). In the development of the MPDBS, challenges that were previously faced by the MOCDTBS were considered. Future challenges in terms of ethical and legal issues will be faced when international collaborations necessitate the transportation of specimens across borders. 相似文献
38.
Myocardial tissue iron delocalization and evidence for lipid peroxidation after two hours of ischemia 总被引:3,自引:0,他引:3
S Holt M Gunderson K Joyce N R Nayini G F Eyster A M Garitano C Zonia G S Krause S D Aust B C White 《Annals of emergency medicine》1986,15(10):1155-1159
Ischemic tissue injury has been proposed to be in part due to oxygen-radical-mediated lipid peroxidation. In vitro studies of such reactions show that they are thermodynamically unfavorable unless catalyzed by transitional metals such as iron in low molecular weight species (LMWS iron), ie, the iron-ADP complex. This study tests for iron delocalization into a LMWS pool during myocardial ischemia and for increased tissue malondialdehyde (MDA), a product of lipid peroxidation. Anesthesia was induced in eight dogs (weighing 20 to 30 kg) with ketamine and maintained by ventilation with 1% halothane. The left anterior descending coronary artery was ligated in four animals, and the circumflex coronary artery was ligated in the other four. Two hours after ligation, the animals were sacrificed by a central venous injection of KCl. Tissue samples were immediately taken from the ischemic zone and from the corresponding nonischemic zone. MDA was determined by the thiobarbituric acid assay. LMWS iron was determined on a tissue ultrafiltrate by the o-phenanthroline assay. Statistical data analysis used the matched-pair two-tailed t test. LMWS iron was 18.3 nM/100 mg in ischemic tissue versus 13.1 nM/100 mg in nonischemic tissue (t = 4.14; P less than .01). MDA was 0.91 nM/100 mg in ischemic tissue versus 0.83 nM/100 mg in nonischemic tissue (t = 7.27; P less than .005). We conclude that there is a significant increase in tissue LMWS iron and in MDA after two hours of regional myocardial ischemia. This iron might be the catalyst for maturation of tissue injury during reperfusion as observed by other investigators.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
39.
40.
Wajdi W. Kanj Melissa A. Gunderson Robert B. Carrigan Wudbhav N. Sankar 《Journal of children's orthopaedics》2013,7(3):225-233