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Find video protocols related to scientific articles indexed in Pubmed.
T cells expressing CD19 chimeric antigen receptors for acute lymphoblastic leukaemia in children and young adults: a phase 1 dose-escalation trial.
Lancet
PUBLISHED: 10-17-2014
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Chimeric antigen receptor (CAR) modified T cells targeting CD19 have shown activity in case series of patients with acute and chronic lymphocytic leukaemia and B-cell lymphomas, but feasibility, toxicity, and response rates of consecutively enrolled patients treated with a consistent regimen and assessed on an intention-to-treat basis have not been reported. We aimed to define feasibility, toxicity, maximum tolerated dose, response rate, and biological correlates of response in children and young adults with refractory B-cell malignancies treated with CD19-CAR T cells.
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Immunotoxins for leukemia.
Blood
PUBLISHED: 02-27-2014
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Unconjugated monoclonal antibodies that target hematopoietic differentiation antigens have been developed to treat hematologic malignancies. Although some of these have activity against chronic lymphocytic leukemia and hairy cell leukemia, in general, monoclonal antibodies have limited efficacy as single agents in the treatment of leukemia. To increase their potency, the binding domains of monoclonal antibodies can be attached to protein toxins. Such compounds, termed immunotoxins, are delivered to the interior of leukemia cells based on antibody specificity for cell surface target antigens. Recombinant immunotoxins have been shown to be highly cytotoxic to leukemic blasts in vitro, in xenograft model systems, and in early-phase clinical trials in humans. These agents will likely play an increasing role in the treatment of leukemia.
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Factors predictive of relapse of acute leukemia in children after allogeneic hematopoietic cell transplantation.
Biol. Blood Marrow Transplant.
PUBLISHED: 01-09-2014
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The presence of minimal residual disease (MRD) before transplantation is the most important prognostic risk factor predictive of post-transplantation relapse in hematologic malignancies. However, MRD alone does not adequately predict relapse in all patients. To improve upon the ability to identify patients likely to relapse, we evaluated risk factors, in addition to MRD, that may be associated with development of post-transplantation relapse. In this single institution, retrospective cohort study of children with acute leukemia or myelodysplastic syndrome who had undergone a first allogeneic transplantation and had pretransplantation MRD evaluation, 40 of 93 patients (43%) experienced relapse. Univariate analysis demonstrated that African American race, high initial white blood cell count, central nervous system (CNS) disease at diagnosis, short first complete remission, nonmyeloablative (NMA) conditioning, lack of remission, and MRD before transplantation were associated with worse relapse-free survival (RFS). In a Cox multivariable analysis, CNS disease (P = .009), lack of remission (P = .01), and NMA conditioning (P = .04) were independently associated with inferior RFS. Among those in a morphologic complete remission who underwent a myeloablative transplantation, having both CNS disease at diagnosis (specifically in acute lymphoblastic leukemia) and MRD positivity was an independent risk factor predictive of relapse, which has not been previously reported. Results from our study support the existence of risk factors complimentary to pretransplantation MRD. Validation in a larger independent homogenous cohort is needed to develop a prognostic tool for clinical use to predict post-transplantation relapse.
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Feasibility of treating post-transplantation minimal residual disease in children with acute leukemia.
Biol. Blood Marrow Transplant.
PUBLISHED: 01-09-2014
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Outcomes are poor for patients with hematologic malignancies who experience overt relapse after allogeneic hematopoietic stem cell transplantation (HCT). Data on outcomes of post-transplantation minimal residual disease (MRD) are limited. In this single-institution, retrospective cohort analysis of children with acute leukemia and myelodysplastic syndrome, we document the pattern of relapse with a primary focus on outcomes of post-transplantation MRD. Forty of 93 patients (43%) who underwent a first allogeneic HCT and had systematic pretransplantation and post-transplantation MRD evaluations at +30, +60, +90, +180 days and +1 and +2 years post-transplantation experienced relapse. The median time to relapse was 4.8 months post-transplantation, with a median survival of 4 months post-relapse. Despite frequent, systematic, routine post-HCT disease restaging evaluation, 31 patients (78%) presented with overt disease at the time of relapse. Seven patients with acute leukemia who had post-transplantation MRD presented at a median of 1 month post-transplantation. Owing to rapid disease progression or treatment-related mortality, there was no improvement in survival in those patients whose leukemia was detected in a state of MRD post-transplantation. Our results suggest that early intervention strategies targeting post-transplantation MRD for relapse prevention in acute leukemia may not be feasible.
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Concentrations of Cocaine and Benzoylecgonine in Femoral Blood from Cocaine-Related Deaths Compared with Venous Blood from Impaired Drivers.
J Anal Toxicol
PUBLISHED: 12-09-2013
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The concentrations of cocaine and its major metabolite benzoylecgonine (BZE) were determined in femoral blood from 132 cocaine-related deaths and compared with venous blood from 988 apprehended drivers. Cocaine and BZE were determined by solid-phase extraction and isotope dilution gas chromatography-mass spectrometry with limits of quantitation of 0.02 mg/L for both substances. Significantly more men (95-98%) than women (2-5%) abused cocaine, although their mean age was about the same (29-30 years). Mean age (±SD) of cocaine-related deaths was 29 ± 7 years, which was not significantly different from 30 ± 8 years in traffic cases (P > 0.05). The median concentration of cocaine in blood in 61 fatalities was 0.10 mg/L compared with 0.06 mg/L in traffic cases (P < 0.001). In drug intoxication deaths, the median concentration of cocaine was 0.13 mg/L (N = 25), which was not significantly different from 0.09 mg/L (N = 36) in other causes of death. Cocaine-related deaths mostly involved mixed drug intoxications including co-ingestion of heroin, cannabis, amphetamines as well as legal drugs, such as benzodiazepines and/or ethanol. The concentrations of cocaine in blood from living and deceased persons overlapped, which makes it infeasible to predict toxicity from the analytical toxicology results alone.
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Prevalence of alcohol and other drugs and the concentrations in blood of drivers killed in road traffic crashes in Sweden.
Scand J Public Health
PUBLISHED: 11-21-2013
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Drunk or drug-impaired drivers represent a major public health and societal problem worldwide. Because over 95% of drivers killed on the roads in Sweden are autopsied, reliable information is available about the use of alcohol and/or other drug before the crash. Methods: This retrospective 4-year study (2008-2011) used a forensic toxicology database (TOXBASE) to evaluate the concentrations of alcohol and other drugs in blood samples from drivers killed in road-traffic crashes. Results: The mean age of all victims (N = 895) was 48 ± 20 years, and the majority were male (86%). In 504 drivers (56%), the results of toxicological analysis were negative and these victims were older; mean age (± SD) 47 ± 20 years, than alcohol positive cases (35 ± 14 years) and illicit drug users (34 ± 15 years). In 21% of fatalities, blood-alcohol concentration (BAC) was above the statutory limit for driving (0.2 g/L), although the median BAC was appreciably higher (1.72 g/L). Illicit drugs (mainly amphetamine and cannabis) were identified in ~7% of victims, either alone (2.5%), together with alcohol (1.8%) or a prescription drug (2%). The psychoactive prescription drugs identified were mainly benzodiazepines, z-hypnotics and tramadol, which were found in the blood of 7.6% of crash victims. Conclusions: The high median BAC in fatally-injured drivers speaks strongly towards alcohol-induced impairment as being responsible for the crash. Compared with alcohol, the prevalence of illicit and psychoactive prescription drugs was fairly low despite a dramatic increase in the number of drug-impaired drivers arrested by the police after a zero-tolerance law was introduced in 1999.
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Proceedings from the National Cancer Institutes Second International Workshop on the Biology, Prevention, and Treatment of Relapse after Hematopoietic Stem Cell Transplantation: introduction.
Biol. Blood Marrow Transplant.
PUBLISHED: 08-25-2013
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Despite advances in hematopoietic stem cell transplantation (HSCT) for the treatment of hematologic malignancies, relapse remains the leading cause of death after transplant. Biologic and clinical investigations are needed to combat this primary cause of death after transplantation. The National Cancer Institute held international workshops in 2009 and 2012 to help address this problem. Three major initiatives for coordinated research were proposed: 1) To establish multicenter networks for basic, translational, epidemiologic and clinical research; 2) To establish a network of biorepositories for the collection of samples before and after HSCT to aid in laboratory and clinical studies; and 3) To refine, implement and study proposed definitions for disease-specific response and relapse and for monitoring of minimal residual disease. The workshop in 2012 also featured nine presentations, summaries of which follow in three manuscripts.
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Proceedings from the National Cancer Institutes Second International Workshop on the Biology, Prevention, and Treatment of Relapse after Hematopoietic Stem Cell Transplantation: Part I. Biology of relapse after transplantation.
Biol. Blood Marrow Transplant.
PUBLISHED: 08-24-2013
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In the National Cancer Institutes Second Workshop on the Biology, Prevention, and Treatment of Relapse after Hematopoietic Stem Cell Transplantation, the Scientific/Educational Session on the Biology of Relapse discussed recent advances in understanding some of the host-, disease-, and transplantation-related contributions to relapse, emphasizing concepts with potential therapeutic implications. Relapse after hematopoietic stem cell transplantation (HSCT) represents tumor escape, from the cytotoxic effects of the conditioning regimen and from immunologic control mediated by reconstituted lymphocyte populations. Factors influencing the biology of the therapeutic graft-versus-malignancy (GVM) effect-and relapse-include conditioning regimen effects on lymphocyte populations and homeostasis, immunologic niches, and the tumor microenvironment; reconstitution of lymphocyte populations and establishment of functional immune competence; and genetic heterogeneity within the malignancy defining potential for clonal escape. Recent developments in T cell and natural killer cell homeostasis and reconstitution are reviewed, with implications for prevention and treatment of relapse, as is the application of modern genome sequencing to defining the biologic basis of GVM, clonal escape, and relapse after HSCT.
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Proceedings from the National Cancer Institutes Second International Workshop on the Biology, Prevention, and Treatment of Relapse after Hematopoietic Stem Cell Transplantation: Part II. Autologous Transplantation-Novel Agents and Immunomodulatory Strateg
Biol. Blood Marrow Transplant.
PUBLISHED: 08-24-2013
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In the National Cancer Institutes Second International Workshop on the Biology, Prevention, and Treatment of Relapse after Hematopoietic Stem Cell Transplantation, the Scientific/Educational Session on Autologous Transplantation addressed the role of novel agents and immunomodulatory strategies in management of relapse after autologous hematopoietic stem cell transplantation (AHSCT). Concepts were illustrated through in-depth discussion of multiple myeloma, with broader discussion of areas relevant for relapse of other malignancies as well as in the setting of allogeneic transplantation. Dr. Hari provided an overview of the epidemiology of relapse after AHSCT in multiple myeloma, addressing clinical patterns, management implications, and treatment options at relapse, highlighting the implications of novel therapeutic agents in initial, maintenance, and relapse treatment. Dr. Avigan discussed current concepts in tumor vaccine design, including whole cell and antigen-specific strategies, use of an AHSCT platform to reverse tumor-associated immunosuppression and tolerance, and combining vaccines with immunomodulatory agents to promote establishment of durable antitumor immunity. Dr. Hsu reviewed the immunogenetics of natural killer (NK) cells and general NK biology, the clinical importance of autologous NK activity (eg, lymphoma and neuroblastoma), the impact of existing therapies on promotion of NK cell activity (eg, immunomodulatory drugs, monoclonal antibodies), and strategies for enhancing autologous and allogeneic NK cell effects through NK cell gene profiling.
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Proceedings from the National Cancer Institutes Second International Workshop on the Biology, Prevention, and Treatment of Relapse after Hematopoietic Stem Cell Transplantation: Part III. Prevention and Treatment of Relapse after Allogeneic Transplantatio
Biol. Blood Marrow Transplant.
PUBLISHED: 08-24-2013
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In the Second Annual National Cancer Institutes Workshop on the Biology, Prevention, and Treatment of Relapse after Hematopoietic Stem Cell Transplantation, the Scientific/Educational Session on the Prevention and Treatment of Relapse after Allogeneic Transplantation highlighted progress in developing new therapeutic approaches since the first relapse workshop. Recent insights that might provide a basis for the development of novel, practical clinical trials were emphasized, including utilization of newer agents, optimization of donor lymphocyte infusion (DLI), and investigation of novel cellular therapies. Dr. de Lima discussed pre-emptive and maintenance strategies to prevent relapse after transplantation, for example, recent promising results suggestive of enhanced graft-versus-tumor activity with hypomethylating agents. Dr. Schmid provided an overview of adjunctive strategies to improve cell therapy for relapse, including cytoreduction before DLI, combination of targeted agents with DLI, and considerations in use of second transplantations. Dr. Porter addressed strategies to enhance T cell function, including ex vivo activated T cells and T cell engineering, and immunomodulatory approaches to enhance T cell function in vivo, including exogenous cytokines and modulation of costimulatory pathways.
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Simplified process for the production of anti-CD19-CAR-engineered T cells.
Cytotherapy
PUBLISHED: 06-08-2013
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Adoptive immunotherapy with the use of chimeric antigen receptor (CAR)-engineered T cells specific for CD19 has shown promising results for the treatment of B-cell lymphomas and leukemia. This therapy involves the transduction of autologous T cells with a viral vector and the subsequent cell expansion. We describe a new, simplified method to produce anti-CD19-CAR T cells.
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Driving under the influence with blood alcohol concentrations over 0.4 g%.
Forensic Sci. Int.
PUBLISHED: 05-04-2013
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The aim of this study was to evaluate the characteristics of traffic offenders with unusually high blood-alcohol concentrations (BAC>0.4 g%) when arrested. The BAC that kills one person might be easily tolerated by another, depending on, among other things, the persons age, pattern of drinking, and the development of tolerance. The archives of two forensic laboratories, one in Sweden and the other in Wisconsin (USA), were searched to find traffic offenders with BACs>0.4 g%. The results were compared in relation to the persons age and gender, mean BAC and the weekday and time of day of the arrest. The mean age (±standard deviation) of N=158 Swedish offenders was 45±9.0 y, which was not significantly different from the 43±9.4 y in N=233 Wisconsin drivers (p>0.05). Overall there were more men (78%) than women (22%) arrested with BACs>0.4 g%, although the proportion of women in Wisconsin (35%) was higher than in Sweden (9%) (p<0.001). The mean (median) and highest BAC did not differ between jurisdictions; 0.429 g% (0.422) and 0.546 g% in Sweden and 0.428 g% (0.421 g%) and 0.526 g% in Wisconsin. In Sweden 40% of the arrests occurred on Fridays and Saturdays, whereas in Wisconsin the arrests of people with such high BACs were more evenly distributed throughout the week. Forty eight percent of the arrests in Sweden were made between 12 noon and 6 pm compared with 37% in Wisconsin. Neither the mean age of offenders nor their mean BAC seemed to depend on the weekday or time of day of the arrest. Attempting to drive with a BAC above 0.4 g% verifies the development of an appreciable tolerance to ethanol-induced cognitive and psychomotor impairment. Reaching such a high BAC probably requires continuous heavy drinking over several days as opposed to an evenings binge drinking.
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A modified form of diphthamide causes immunotoxin resistance in a lymphoma cell line with a deletion of the WDR85 gene.
J. Biol. Chem.
PUBLISHED: 03-13-2013
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HA22 is a recombinant immunotoxin that kills CD22-expressing cells by ADP-ribosylating and inactivating elongation factor-2 (EF2). HA22 is composed of an Fv that binds to CD22 fused to a portion of Pseudomonas exotoxin A. HA22 is very active in drug-resistant hairy cell leukemia but is less active in children with acute lymphoblastic leukemia. To understand why some patients do not respond to HA22, we isolated an HA22-resistant lymphoma cell line and showed that resistance was due to the inability of HA22 to ADP-ribosylate and inactivate EF2. We analyzed the diphthamide synthesis genes and found that the WDR85 gene was deleted. We show that WDR85 knockdown conferred HA22 resistance to sensitive cells and that sensitivity was restored by introduction of a WDR85 cDNA into resistant cells. Analysis of EF2 in the mutant cells revealed a novel form of diphthamide with an additional methyl group that prevented ADP-ribosylation and inactivation of EF2. The abnormal methylation appeared to be catalyzed by DPH5. Inactivation of the WDR85 gene could be a mechanism of immunotoxin resistance in patients undergoing immunotoxin therapy.
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Methylation of the DPH1 promoter causes immunotoxin resistance in acute lymphoblastic leukemia cell line KOPN-8.
Leuk. Res.
PUBLISHED: 03-12-2013
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Moxetumomab pasudotox (HA22) is an immunotoxin with an anti-CD22 Fv fused to a portion of Pseudomonas exotoxin A that kills CD22 expressing ALL cells. HA22 produced significant responses in some cases of ALL. To understand how to increase response rate, we isolated HA22-resistant KOPN-8 cells and found that HA22 cannot inactivate elongation factor-2 (EF2) due to low levels of DPH1 RNA and protein. Resistance was associated with methylation of the CpG island in the DPH1 promoter. 5-Azacytidine prevented resistance and methylation of the CpG residues and merits evaluation to determine if it can increase the efficacy of HA22 in ALL.
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Toxicology findings in suicides: concentrations of ethanol and other drugs in femoral blood in victims of hanging and poisoning in relation to age and gender of the deceased.
J Forensic Leg Med
PUBLISHED: 02-28-2013
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Over-consumption of alcohol and/or abuse of other drugs are closely linked to attempted or completed suicides. In this retrospective 10-year study (2001-2010), we compared the toxicology findings in hanging suicides (n = 4551) with drug poisoning (intoxication) suicides (n = 2468). The mean age of hanging deaths was 49 ± 19 y (±SD) and 80% were male, compared with a mean age of 52 ± 17 y and 47% males for the intoxication deaths. Poly-drug use was more common in poisoning suicides with an average of 3.6 drugs/case compared with 1.8 drugs/case in hangings. Moreover, 31% of hangings were negative for alcohol and/or drugs. Alcohol was detected (>0.20 g/L) in femoral blood in 30% of hanging suicides (mean 1.39 g/L) and 36% of drug poisonings (mean 1.39 g/L). The median BACs did not depend on the persons age or gender (p > 0.05). Ethanol, paracetamol, citalopram, diazepam, propiomazine, alimemazine and zopiclone were amongst the top-ten drugs detected in both methods of suicide. With the exception of ethanol, the concentrations of drugs in blood were considerably higher in the poisoning deaths, as might be expected. Regardless of the method of suicide, antidepressants and/or antipsychotics were common findings, which could implicate mental health as a significant suicide risk factor.
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Amphetamine abuse in Sweden: subject demographics, changes in blood concentrations over time, and the types of coingested substances.
J Clin Psychopharmacol
PUBLISHED: 02-21-2013
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Amphetamine is a major drug of abuse in Sweden and in the other Nordic countries. The demographics of amphetamine abusers in Sweden and the concentrations of this stimulant in blood are reported for 10 years of forensic blood samples (2001-2010). Using a forensic toxicology database (TOXBASE), we studied 1183 amphetamine-related deaths, 20,452 users of illicit drugs, and 47,366 people arrested for driving under the influence of drugs (DUID). Most amphetamine abusers were male (82%-87%), and their average age was 33 to 39 years with males being 2 to 3 years older than females (P < 0.001). Mean (median) concentrations of amphetamine in blood were 1.25 (0.40) mg/L in autopsy cases, 0.61 (0.40) mg/L in users of illicit drugs, and 0.76 (0.58) mg/L in DUID suspects. Median concentration in DUID suspects was significantly higher than in the other forensic materials (P < 0.001). Women also had higher median concentrations of amphetamine in blood than male abusers of this central stimulant (P < 0.001). The major coingested drugs were benzodiazepines (41%), cannabis (26%), opiates (21%), and alcohol (18%) in autopsy cases. Polydrug use was less common in DUID suspects and users of illicit drugs, although benzodiazepines (13%), tetrahydrocannabinol (12%), and opiates (5%) were often identified along with amphetamine. Because median concentration of amphetamine was higher in living subjects (DUID suspects) compared with amphetamine-related deaths, this points toward toxicity of coingested drugs or adverse drug-drug interaction as being responsible for death.
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Pharmacokinetics of intravenous voriconazole in obese patients: implications of CYP2C19 homozygous poor metabolizer genotype.
Pharmacotherapy
PUBLISHED: 02-11-2013
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There is a paucity of pharmacokinetic studies describing weight-based dosing of intravenous voriconazole in obese patients. In this case report, we describe the pharmacokinetics of intravenous voriconazole in an obese CYP2C19 homozygous poor metabolizer and review previously reported data regarding the use of intravenous voriconazole in obese patients. A 17-year-old obese Hispanic male patient (body mass index 35 kg/m(2) ) received intravenous voriconazole for the treatment of suspected aspergillosis. After 2.5 days of voriconazole 4 mg/kg intravenously every 12 hours based on adjusted body weight, the voriconazole area under the serum concentration-time curve over the course of a single (12-hr) dosing interval and trough concentration were 86,100 ng · hr/ml and 6.2 µg/ml, respectively. Six days later, the voriconazole dosage was decreased. A trough concentration measured just before the dosage reduction (after 8.5 days of voriconazole 4 mg/kg intravenously every 12 hours based on adjusted body weight) remained elevated at 5.8 µg/ml. Genotyping revealed a CYP2C19 homozygous poor metabolizer (CYP2C19*2/*2). Voriconazole was subsequently discontinued due to QTc prolongation. These data and those from two recent publications suggest that voriconazole does not distribute extensively into human adipose tissue and that obese patients should be dosed on an adjusted body weight basis. If an obese patient dosed on total body weight is also a CYP2C19 poor metabolizer, serum voriconazole concentrations will be further elevated, potentially leading to drug-induced toxicity.
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Immunotherapy for pediatric leukemia.
Front Oncol
PUBLISHED: 01-01-2013
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Substantial progress has been made in the treatment of leukemia in childhood. Despite this, leukemia remains a leading cause of pediatric cancer-related mortality and the prognosis is guarded for individuals with relapsed or refractory disease. Standard therapies are associated with a wide array of acute and long-term toxicities and further treatment intensification may not be tolerable or beneficial. The curative potential of allogeneic stem cell transplantation is due in part to the graft-versus-leukemia effect, which provides evidence for the therapeutic capacity of immune-based therapies. In recent years there have been significant advances in the development and application of immunotherapy in the treatment of leukemias, including the demonstration of activity in chemotherapy-resistant cases. This review summarizes immunotherapeutic approaches in the treatment of pediatric leukemia including current results and future directions.
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Treatment of hematologic malignancies with immunotoxins and antibody-drug conjugates.
Cancer Res.
PUBLISHED: 10-15-2011
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To enable antibodies to function as cytotoxic anticancer agents, they are modified either via attachment to protein toxins or highly potent, low-molecular-weight drugs. Such molecules, termed immunotoxins and antibody-drug conjugates, respectively, represent a second revolution in antibody-mediated cancer therapy. Thus, highly toxic compounds are delivered to the interior of cancer cells based on antibody specificity for cell-surface target antigens.
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Quantitative analysis of amphetamine in femoral blood from drug-poisoning deaths compared with venous blood from impaired drivers.
Bioanalysis
PUBLISHED: 10-12-2011
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Background: Amphetamine is a major drug of abuse worldwide. Here we compare the concentrations of this stimulant amine in femoral blood in drug fatalities with venous blood from impaired drivers. Method: Amphetamine was determined in blood by isotope-dilution GC-MS after liquid-liquid extraction. Results: Amphetamine was the only drug identified in 36 fatalities at mean (median) and highest concentrations of 2.0 mg/l (1.5 mg/l) and 14.0 mg/l. In multiple-drug deaths (n = 383), the concentrations were 0.94 mg/l (0.4 mg/l) and 13.3 mg/l. In impaired drivers with amphetamine as the only drug (n = 6138), the concentrations were 1.0 mg/l (0.8 mg/l) and 11.9 mg/l, compared with 0.78 mg/l (0.6 mg/l) and 22.3 mg/l in multidrug users (n = 8250). Conclusion: Fatal amphetamine poisonings cannot be identified on the basis of the concentration in blood alone, owing to the development of tolerance and the toxicity of co-ingested substances.
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Reduced-intensity allogeneic stem cell transplantation in children and young adults with ultrahigh-risk pediatric sarcomas.
Biol. Blood Marrow Transplant.
PUBLISHED: 07-12-2011
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Some subsets of pediatric sarcoma patients have very poor survival rates. We sought to determine the feasibility and efficacy of allogeneic hematopoietic stem cell transplantation (alloHSCT) in pediatric sarcoma populations with <25% predicted overall survival (OS). Patients with ultrahigh-risk Ewings sarcoma family of tumors (ESFT), alveolar rhabdomyosarcoma, or desmoplastic small round cell tumors received EPOCH-fludarabine induction, a cyclophosphamide/fludarabine/melphalan preparative regimen, and HLA matched related peripheral blood stem cells. Thirty patients enrolled; 7 did not undergo alloHSCT because of progressive disease with diminishing performance status during induction. All 23 alloHSCT recipients experienced rapid full-donor engraftment, with no peritransplantation mortality. Five of 23 alloHSCT recipients (22%) remain alive (OS of 30% by Kaplan-Meier analysis at 3 years), including 3 of 7 (42%) transplanted without overt disease (median survival 14.5 versus 29.0 months from alloHSCT for patients transplanted with versus without overt disease, respectively). Among the 28 patients who progressed on the study, the median survival from date of progression was 1.9 months for the 7 who did not receive a transplant compared with 11.4 months for the 21 transplanted (P = .0003). We found prolonged survival after posttransplantation progression with several patients exhibiting indolent tumor growth. We also saw several patients with enhanced antitumor effects from posttransplantation chemotherapy (objective response to pretransplantation EPOCH-F was 24% versus 67% to posttransplantation EOCH); however, this was associated with increased toxicity. This largest reported series of alloHSCT in sarcomas demonstrates that alloHSCT is safe in this population, and that patients undergoing alloHSCT without overt disease show higher survival rates than reported using standard therapies. Enhanced chemo- and radiosensitivity of tumors and normal tissues was observed posttransplantation.
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Myeloid dysplasia and bone marrow hypocellularity in adenosine deaminase-deficient severe combined immune deficiency.
Blood
PUBLISHED: 07-01-2011
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Genetic deficiency of adenosine deaminase (ADA) can cause profound lymphopenia and result in the clinical presentation of severe combined immune deficiency (SCID). However, because of the ubiquitous expression of ADA, ADA-deficient patients often present also with nonimmunologic clinical problems, affecting the skeletal, central nervous, endocrine, and gastrointestinal systems. We now report that myeloid dysplasia features and bone marrow hypocellularity are often found in patients with ADA-SCID. As a clinical correlate to this finding, we have observed vulnerability to antibiotic-induced myelotoxicity and prolonged neutropenia after nonmyeloablative chemotherapy. We have also noted that, in the absence of enzyme replacement therapy, absolute neutrophil counts of patients with ADA deficiency vary inversely with the accumulation of deoxynucleotides. These data have significant implications for the application of standard and investigational therapies to patients with ADA-SCID and support further studies to investigate the possibility that ADA deficiency is associated with a stem cell defect. These trials were registered at www.clinicaltrials.gov as #NCT00018018 and #NCT00006319.
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Early drug discovery and the rise of pharmaceutical chemistry.
Drug Test Anal
PUBLISHED: 06-24-2011
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Studies in the field of forensic pharmacology and toxicology would not be complete without some knowledge of the history of drug discovery, the various personalities involved, and the events leading to the development and introduction of new therapeutic agents. The first medicinal drugs came from natural sources and existed in the form of herbs, plants, roots, vines and fungi. Until the mid-nineteenth century natures pharmaceuticals were all that were available to relieve mans pain and suffering. The first synthetic drug, chloral hydrate, was discovered in 1869 and introduced as a sedative-hypnotic; it is still available today in some countries. The first pharmaceutical companies were spin-offs from the textiles and synthetic dye industry and owe much to the rich source of organic chemicals derived from the distillation of coal (coal-tar). The first analgesics and antipyretics, exemplified by phenacetin and acetanilide, were simple chemical derivatives of aniline and p-nitrophenol, both of which were byproducts from coal-tar. An extract from the bark of the white willow tree had been used for centuries to treat various fevers and inflammation. The active principle in white willow, salicin or salicylic acid, had a bitter taste and irritated the gastric mucosa, but a simple chemical modification was much more palatable. This was acetylsalicylic acid, better known as Aspirin®, the first blockbuster drug. At the start of the twentieth century, the first of the barbiturate family of drugs entered the pharmacopoeia and the rest, as they say, is history.
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Fatality from drinking denatured alcohol and hypothermia.
J Anal Toxicol
PUBLISHED: 05-31-2011
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A 19-year-old non-diabetic female suffering from irritable bowel syndrome was found unconscious outdoors in the month of October. She was severely hypothermic and rushed to hospital for life-saving treatment. Evidence emerged that the victim had attempted suicide by drinking denatured alcohol (T-Red). According to the manufacturer of this product, it contains > 85% (v/v) ethanol, ~5% (v/v) acetone, 1-2% (v/v) ethyl acetate, and ?3% (v/v) methyl ethyl ketone (MEK), but no isopropanol. A venous blood sample taken on admission to hospital contained ethanol (660 mg/100 mL), acetone (25 mg/100 mL), isopropanol (78 mg/100 mL), and MEK, although the latter was not quantified. Despite intensive care, the patient died 21 h after admission and postmortem femoral blood contained ethanol (390 mg/100 mL), acetone (14 mg/100 mL), isopropanol (53 mg/100 mL), and MEK. During oxidative metabolism of ethanol, there is a shift in the redox state of the liver to a more reduced potential as reflected in a raised NADH/NAD(+) ratio, which impacts on other NAD-dependent biochemical reactions, including reduction of acetone to isopropanol. The lower concentrations of ethanol, acetone, and isopropanol in postmortem blood compared with antemortem blood indicate the metabolism of these substances during the 21-h survival period when the patient received emergency hospital treatment.
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Enhancing immunotoxin cell-killing activity via combination therapy with ABT-737.
Leuk. Lymphoma
PUBLISHED: 05-24-2011
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Immunotoxins are antibody-toxin fusion proteins directed to kill cancer cells displaying specific target antigens on their surface. Remarkably, immunotoxins directed to CD22 on hairy cell leukemia have produced complete remissions in approximately 60% of patients enrolled in phase I/II trials. For reasons that are not yet clear, 40% of patients responded less well. In addition, patients with other CD22-positive malignancies have not yet achieved complete remissions. In trying to understand resistance to immunotoxin therapy, a number of challenging issues have been raised. These include insufficient dosing, the production of neutralizing anti-immunotoxin antibodies, poor access to malignant cells, and resistance to toxin killing. In designing immunotoxins, we employ truncated Pseudomonas exotoxin, which enzymatically inactivates protein synthesis and produces cell death in sensitive cells. To begin to address toxin resistance we have explored combination therapy with the BH3-only mimetic, ABT-737. Our results indicate that immunotoxin-ABT combinations often exhibit greater killing activity than either compound alone and in some instances overcome resistance. Expression of high levels of prosurvival Bcl-2 proteins may contribute to toxin resistance.
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Multicentric dermatofibrosarcoma protuberans in patients with adenosine deaminase-deficient severe combined immune deficiency.
J. Allergy Clin. Immunol.
PUBLISHED: 04-04-2011
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Dermatofibrosarcoma protuberans (DFSP) is a rare malignant skin tumor associated with a characteristic chromosomal translocation (t[17;22][q22;q13]) resulting in the COL1A1-platelet-derived growth factor ?(PDGFB) fusion gene. This malignancy is rarely diagnosed in childhood.
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Characterization and treatment of chronic active Epstein-Barr virus disease: a 28-year experience in the United States.
Blood
PUBLISHED: 03-31-2011
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Chronic active EBV disease (CAEBV) is a lymphoproliferative disorder characterized by markedly elevated levels of antibody to EBV or EBV DNA in the blood and EBV RNA or protein in lymphocytes in tissues. We present our experience with CAEBV during the last 28 years, including the first 8 cases treated with hematopoietic stem cell transplantation in the United States. Most cases of CAEBV have been reported from Japan. Unlike CAEBV in Japan, where EBV is nearly always found in T or natural killer (NK) cells in tissues, EBV was usually detected in B cells in tissues from our patients. Most patients presented with lymphadenopathy and splenomegaly; fever, hepatitis, and pancytopenia were common. Most patients died of infection or progressive lymphoproliferation. Unlike cases reported from Japan, our patients often showed a progressive loss of B cells and hypogammaglobulinemia. Although patients with CAEBV from Japan have normal or increased numbers of NK cells, many of our patients had reduced NK-cell numbers. Although immunosuppressive agents, rituximab, autologous cytotoxic T cells, or cytotoxic chemotherapy often resulted in short-term remissions, they were not curative. Hematopoietic stem cell transplantation was often curative for CAEBV, even in patients with active lymphoproliferative disease that was unresponsive to chemotherapy. These studies are registered at http://www.clinicaltrials.gov as NCT00032513 for CAEBV, NCT00062868 and NCT00058812 for EBV-specific T-cell studies, and NCT00578539 for the hematopoietic stem cell transplantation protocol.
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Bexarotene is active against subcutaneous panniculitis-like T-cell lymphoma in adult and pediatric populations.
Clin Lymphoma Myeloma Leuk
PUBLISHED: 03-27-2011
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Subcutaneous panniculitis-like T-cell lymphoma (SPTL-AB) and cutaneous gamma/delta T-cell lymphoma (CGD-TCL) are rare T-cell lymphomas with varying clinical courses. There is no standard treatment, although chemotherapy and hematopoietic stem cell transplantation are commonly used. We describe results using bexarotene for children and adults with these disorders.
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Activating signals dominate inhibitory signals in CD137L/IL-15 activated natural killer cells.
J. Immunother.
PUBLISHED: 02-10-2011
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Natural killer (NK) cells can mediate potent antitumor effects, but factors regulating the efficiency of tumor lysis remain unclear. Studies in allogeneic stem cell transplantation highlight an important role for killer cell immunoglobulin-like receptor (KIR) mismatch in overcoming human leukocyte antigen-mediated inhibitory signals. However, other activating and inhibitory signals also modulate tumor lysis by NK cells. We used rhIL15 and artificial antigen presenting cells expressing CD137L and IL15R? to activate and expand peripheral blood NK cells (CD137L/IL15 NK) up to 1000-fold in 3 weeks. Compared with resting NK cells, CD137L/IL15 NK cells show modest increases in KIR expression and substantial increases in NKG2D, tumor necrosis factor-related apoptosis-inducing ligand, and natural cytotoxicity receptors (NCRs: NKp30, NKp44, NKp46). Compared with resting NK cells, CD137L/IL15 NK cells mediate enhanced cytotoxicity against allogeneic and autologous tumors and KIR signaling did not substantially inhibit cytotoxicity. Rather, tumor lysis by CD137L/IL15 activated NK cells was predominantly driven by NCR signaling as blockade of NCRs dramatically diminished the lysis of a wide array of tumor targets. Furthermore, tumor lysis by CD137L/IL15 NK cells was tightly linked to NCR expression levels that peaked on day 8 to 10 after NK activation, and cytotoxicity diminished on subsequent days as NCR expression declined. We conclude that KIR mismatch is not a prerequisite for tumor killing by CD137L/IL15 NK cells and that NCR expression provides a biomarker for predicting potency of CD137L/IL15 NK cells in studies of NK cell-based immunotherapy.
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Biomarkers of recent drinking, retrograde extrapolation of blood-alcohol concentration and plasma-to-blood distribution ratio in a case of driving under the influence of alcohol.
J Forensic Leg Med
PUBLISHED: 02-02-2011
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This case report describes the police investigation of a road-traffic accident involving a collision at night (01.00 am) between a car and a truck in which a passenger in the car was killed. The driver of the truck was found responsible for the crash although a roadside breath-alcohol test was negative (<0.1 mg/L breath or 20 mg/100 mL blood). Because of injuries sustained in the crash, the female driver of the car was not breath-tested at the time but was transported to a local hospital for emergency treatment. After swabbing the skin with isopropanol an indwelling catheter was inserted at 01.40 am. A blood sample was taken at 02.10 am and the plasma portion contained 8 mmol/L ethanol according to analysis at the hospital clinical laboratory using a gas chromatographic method. Another blood sample was taken at 05.45 am for analysis of ethanol at a forensic toxicology laboratory, although the result was negative (<10 mg/100 mL). The police authorities wanted an explanation for the discrepancy between the clinical and forensic laboratory results and inquired whether the driver of the car was above the legal alcohol limit (>20 mg/100 mL) at the time of the crash. The scientific basis for converting a plasma-ethanol concentration into a blood-ethanol concentration and back extrapolation of the drivers blood-alcohol concentration (BAC) is explained. The risk of contaminating a blood sample by swabbing the skin with isopropanol is discussed along with the use of alcohol biomarkers (ethyl glucuronide and ethyl sulphate) as evidence of recent drinking.
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National Cancer Institutes First International Workshop on the Biology, Prevention, and Treatment of Relapse after Allogeneic Hematopoietic Stem Cell Transplantation: summary and recommendations from the organizing committee.
Biol. Blood Marrow Transplant.
PUBLISHED: 01-09-2011
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The National Cancer Institutes First International Workshop on the Biology, Prevention, and Treatment of Relapse after Allogeneic Hematopoietic Stem Cell Transplantation was organized and convened to identify, prioritize, and coordinate future research activities related to relapse after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Each of the Workshops 6 Working Committees has published individual reports of ongoing basic, translational, and clinical research and recommended areas for future research related to the areas of relapse biology, epidemiology, prevention, and treatment. This document summarizes each committees recommendations and suggests 3 major initiatives for a coordinated research effort to address the problem of relapse after allo-HSCT: (1) to establish multicenter correlative and clinical trial networks for basic/translational, epidemiologic, and clinical research; (2) to establish a network of biorepositories for the collection of samples before and after allo-HSCT to aid in laboratory and clinical studies; and (3) to further refine, implement, and study the Workshop-proposed definitions for disease-specific response and relapse and recommendations for monitoring of minimal residual disease. These recommendations, in coordination with ongoing research initiatives and transplantation organizations, provide a research framework to rapidly and efficiently address the significant problem of relapse after allo-HSCT.
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NCI First International Workshop on the Biology, Prevention, and Treatment of Relapse after Allogeneic Hematopoietic Stem Cell Transplantation: Report from the Committee on Treatment of Relapse after Allogeneic Hematopoietic Stem Cell Transplantation.
Biol. Blood Marrow Transplant.
PUBLISHED: 08-03-2010
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Relapse is a major cause of treatment failure after allogeneic hematopoietic stem cell transplantation (alloHSCT). Treatment options for relapse have been inadequate, and the majority of patients ultimately die of their disease. There is no standard approach to treating relapse after alloHSCT. Withdrawal of immune suppression and donor lymphocyte infusions are commonly used for all diseases; although these interventions are remarkably effective for relapsed chronic myelogenous leukemia, they have limited efficacy in other hematologic malignancies. Conventional and novel chemotherapy, monoclonal antibody therapy, targeted therapies, and second transplants have been utilized in a variety of relapsed diseases, but reports on these therapies are generally anecdotal and retrospective. As such, there is an immediate need for well-designed, disease-specific trials for treatment of relapse after alloHSCT. This report summarizes current treatment options under investigation for relapse after alloHSCT in a disease-specific manner. In addition, recommendations are provided for specific areas of research necessary in the treatment of relapse after alloHSCT.
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Blastic plasmacytoid dendritic cell neoplasm in children: diagnostic features and clinical implications.
Haematologica
PUBLISHED: 07-27-2010
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Blastic plasmacytoid dendritic cell neoplasm is a rare malignancy that typically follows a highly aggressive clinical course in adults, whereas experience in children with this disease is very limited.
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NCI first international workshop on the biology, prevention, and treatment of relapse after allogeneic hematopoietic stem cell transplantation: report from the committee on disease-specific methods and strategies for monitoring relapse following allogenei
Biol. Blood Marrow Transplant.
PUBLISHED: 07-03-2010
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Relapse has become the major cause of treatment failure after allogeneic hematopoietic stem cell transplantation. Outcome of patients with clinical relapse after transplantation generally remains poor, but intervention prior to florid relapse improves outcome for certain hematologic malignancies. To detect early relapse or minimal residual disease, sensitive methods such as molecular genetics, tumor-specific molecular primers, fluorescence in situ hybridization (FISH), and multiparameter flow cytometry (MFC) are commonly used after allogeneic stem cell transplantation to monitor patients, but not all of them are included in the commonly employed disease-specific response criteria. The highest sensitivity and specificity can be achieved by molecular monitoring of tumor- or patient-specific markers measured by polymerase chain reaction-based techniques, but not all diseases have such targets for monitoring. Similar high sensitivity can be achieved by determination of recipient-donor chimerism, but its specificity regarding detection of relapse is low and differs substantially among diseases. Here, we summarize the current knowledge about the utilization of such sensitive monitoring techniques in chronic leukemias, myeloproliferative neoplasms, and lymphoid malignancies based on tumor-specific markers and cell chimerism and how these methods might augment the standard definitions of posttransplant remission, persistence, progression, relapse, and the prediction of relapse. Critically important is the need for standardization of the different residual disease techniques and to assess the clinical relevance of minimal residual disease and chimerism surveillance in individual diseases, which in turn must be followed by studies to assess the potential impact of specific interventional strategies.
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Cytotoxicity of the anti-CD22 immunotoxin HA22 (CAT-8015) against paediatric acute lymphoblastic leukaemia.
Br. J. Haematol.
PUBLISHED: 06-07-2010
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Acute lymphoblastic leukaemia (ALL) remains the most frequent cause of cancer-related mortality in paediatrics and outcome is poor for patients who have high-risk ALL or relapse. HA22 (CAT-8015) is an immunotoxin composed of an anti-CD22 variable fragment linked to a 38 kDa truncated protein derived from Pseudomonas exotoxin A. Using a bone marrow mesenchymal cell culture assay to support ALL cell viability, we investigated the in vitro cytotoxicity of HA22 against ALL blasts from newly diagnosed (n = 13) and relapsed patients (n = 22). There was interpatient variability in sensitivity to HA22. Twenty-four of 35 patient samples tested were sensitive (median 50% lethal concentration 3 ng/ml, range 1-80 ng/ml). Blasts from the other 11 patients were not killed by 500 ng/ml HA22. The median 50% lethal concentration was 20 ng/ml for all patients. There was no significant difference in HA22 sensitivity between diagnosis and relapse samples but peripheral blood ALL blasts were more sensitive to HA22 than those from bone marrow (P = 0.008). Thus, HA22, at concentrations achievable in patients, is highly cytotoxic to B-lineage ALL cells. These results provide a strong rationale for clinical testing of this agent in children with drug-resistant ALL and offers the potential to reduce morbidities of treatment while improving outcome.
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Hematopoietic stem cell transplantation for leukemia.
Pediatr. Clin. North Am.
PUBLISHED: 03-24-2010
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Leukemia represents the most common pediatric malignancy, accounting for approximately 30% of all cancers in children less than 20 years of age. Most children diagnosed with leukemia are cured without hematopoietic stem cell transplantation (HSCT), but for some high-risk subgroups, allogeneic HSCT plays an important role in their therapeutic approach. The characteristics of these high-risk subgroups and the role of HSCT in childhood leukemias are discussed.
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Variables affecting the quantitation of CD22 in neoplastic B cells.
Cytometry B Clin Cytom
PUBLISHED: 03-19-2010
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Quantitative flow cytometry (QFCM) is being applied in the clinical flow cytometry laboratory for diagnosis, prognosis, and assessment of patients receiving antibody-based therapy. ABC values and the effect of technical variables on CD22 quantitation in acute lymphoblastic leukemia (ALL), chronic lymphocytic leukemia (CLL), mantle cell lymphoma (MCL), follicular lymphoma (FCL), hairy cell leukemia (HCL) and normal B cells were studied.
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Anti-CD22 immunotoxin RFB4(dsFv)-PE38 (BL22) for CD22-positive hematologic malignancies of childhood: preclinical studies and phase I clinical trial.
Clin. Cancer Res.
PUBLISHED: 03-09-2010
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Although most children with B-lineage acute lymphoblastic leukemia (ALL) and non-Hodgkin lymphoma are cured, new agents are needed to overcome drug resistance and reduce toxicities of chemotherapy. We hypothesized that the novel anti-CD22 immunotoxin, RFB4(dsFv)-PE38 (BL22, CAT-3888), would be active and have limited nonspecific side effects in children with CD22-expressing hematologic malignancies. We conducted the first preclinical and phase I clinical studies of BL22 in that setting.
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NCI First International Workshop on the Biology, Prevention, and Treatment of Relapse after Allogeneic Hematopoietic Stem Cell Transplantation: report from the Committee on Disease-Specific Methods and Strategies for Monitoring Relapse following Allogenei
Biol. Blood Marrow Transplant.
PUBLISHED: 02-10-2010
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Relapse has become the major cause of treatment failure after allogeneic stem cell transplantation. Outcome of patients with clinical relapse after transplantation generally remains poor, but intervention prior to florid relapse improves outcome for certain hematologic malignancies. To detect early relapse or minimal residual disease, sensitive methods such as molecular genetics, tumor-specific molecular primers, fluorescein in situ hybridization, and multiparameter flow cytometry (MFC) are commonly used after allogeneic stem cell transplantation to monitor patients, but not all of them are included in the commonly employed disease-specific response criteria. The highest sensitivity and specificity can be achieved by molecular monitoring of tumor- or patient-specific markers measured by polymerase chain reaction-based techniques, but not all diseases have such targets for monitoring. Similar high sensitivity can be achieved by determination of donor chimerism, but its specificity regarding detection of relapse is low and differs substantially among diseases. Here, we summarize the current knowledge about the utilization of such sensitive monitoring techniques based on tumor-specific markers and donor cell chimerism and how these methods might augment the standard definitions of posttransplant remission, persistence, progression, relapse, and the prediction of relapse. Critically important is the need for standardization of the different residual disease techniques and to assess the clinical relevance of minimal residual disease and chimerism surveillance in individual diseases, which in turn, must be followed by studies to assess the potential impact of specific interventional strategies.
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Evidence-based survey of the elimination rates of ethanol from blood with applications in forensic casework.
Forensic Sci. Int.
PUBLISHED: 02-05-2010
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Reliable information about the elimination rate of alcohol (ethanol) from blood is often needed in forensic science and legal medicine when alcohol-related crimes, such as drunken driving or drug-related sexual assault are investigated. A blood sample for forensic analysis might not be taken until several hours after an offence was committed. The courts usually want to know the suspects blood-alcohol concentration (BAC) at some earlier time, such as the time of driving. Making these back calculations or retrograde extrapolations of BAC in criminal cases has many proponents and critics. Ethanol is eliminated from the body mainly by oxidative metabolism in the liver by Class I isoenzymes of alcohol dehydrogenase (ADH). Ethanol is an example of a drug for which the Michaelis-Menten pharmacokinetic model applies and the Michaelis constant (k(m)) for Class I ADH is at a BAC of 2-10mg/100mL. This means that the enzyme is saturated with substrate after the first few drinks and that zero-order kinetics is adequate to describe the declining phase of the BAC profile in most forensic situations (BAC>20mg/100mL). After drinking on an empty stomach, the elimination rate of ethanol from blood falls within the range 10-15 mg/100mL/h. In non-fasted subjects the rate of elimination tends to be in the range 15-20mg/100mL/h. In alcoholics during detoxification, because activity of microsomal enzyme (CYP2E1) is boosted, the ethanol elimination rate might be 25-35 mg/100mL/h. The slope of the BAC declining phase is slightly steeper in women compared with men, which seems to be related to gender differences in liver weight in relation to lean body mass. The present evidence-based review suggests that the physiological range of ethanol elimination rates from blood is from 10 to 35 mg/100mL/h. In moderate drinkers 15 mg/100mL/h remains a good average value for the population, whereas in apprehended drivers 19 mg/100mL/h is more appropriate, since many of these individuals are binge drinkers or alcoholics. In preparing this article, a large number of peer-reviewed publications were scrutinized. Only those meeting certain standards in experimental design, dose of alcohol and blood-sampling protocol were used. The results presented can hopefully serve as best-practice guidelines when questions arise in criminal and civil litigation about the elimination rate of ethanol from blood in humans.
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The role of tumor histogenesis, FDG-PET, and short-course EPOCH with dose-dense rituximab (SC-EPOCH-RR) in HIV-associated diffuse large B-cell lymphoma.
Blood
PUBLISHED: 02-03-2010
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This is a phase 2 study to assess the role of tumor histogenesis (subtype), fluorodeoxyglucose positron emission tomography (FDG-PET), and short-course etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin with dose-dense rituximab (SC-EPOCH-RR) in newly diagnosed HIV-associated CD20(+) diffuse large B-cell lymphoma. Patients received a minimum of 3 and a maximum of 6 cycles with 1 cycle beyond stable radiographic and FDG-PET scans. Overall, 79% of patients received 3 cycles. Combination antiretroviral therapy was suspended before and resumed after therapy. Thirty-three enrolled patients had a median age of 42 years (range, 9-61 years), and 76% had a high-intermediate or high age-adjusted international prognostic index. At 5 years median follow-up, progression-free and overall survival were 84% and 68%, respectively. There were no treatment-related deaths or new opportunistic infections during treatment, and patients had sustained CD4 cell count recovery and HIV viral control after treatment. FDG-PET after 2 cycles had an excellent negative but poor positive predictive value. Tumor histogenesis was the only characteristic associated with lymphoma-specific outcome with 95% of germinal center B-cell (GCB) versus 44% of non-GCB diffuse large B-cell lymphoma (DLBCL) progression-free at 5 years. SC-EPOCH-RR is highly effective and less immunosuppressive with shorter duration therapy compared with standard strategies. However, new therapeutic advances are needed for non-GCB DLBCL, which remains the important cause of lymphoma-specific death. This trial was registered at www.clinicaltrials.gov as NCT000019253.
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Demographics of suicide victims in Sweden in relation to their blood-alcohol concentration and the circumstances and manner of death.
Forensic Sci. Int.
PUBLISHED: 01-06-2010
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Specimens of blood and other body fluids were obtained at autopsy from all deaths in Sweden classified as suicide covering a 10-year period (N=11,441 cases). The mean age (+/-standard deviation, SD) of the victims was 51.3+/-18.8 years with a clear predominance of males 71% (mean age 51.3+/-18.8 years) compared with 29% females (mean age 51.4+/-18.9 years). The concentration of ethanol in blood samples was determined in duplicate by headspace gas chromatography and a mean blood-alcohol concentration (BAC) of 0.1g/L (10mg/100mL) was the cut-off used to identify ethanol positive cases. The suicides were coded (ICD-9) as self-poisonings (N=2462, 22%), hanging (N=4474, 39%), asphyxia by gas (N=509, 4.4%), drowning (N=803, 7.0%), gun shot (N=1307, 11.4%), fall from height (N=632, 5.5%), self-inflicted cuts or sharp-force injury (N=363, 3.1%) and miscellaneous ways (N=891, 7.8%). On average 34% of all suicide victims in Sweden had consumed alcohol before death, 36% of the males and 31% of the females had a positive BAC. The mean (median) concentration of alcohol in femoral blood for men was 1.34g/L (1.3g/L) compared with 1.25g/L (1.1g/L) for women. Many victims were heavily intoxicated and the 90th percentiles of the BAC distributions ranged from 2.3 to 2.8g/L depending on manner of death. Elevated blood-alcohol was most prevalent in poisoning deaths (45%) and gas asphyxia (51%) and least prevalent in falls from height (19%) and sharp-force injury (18%). Toxicological analysis for presence of drugs other than alcohol showed a predominance of paracetamol, SSRI antidepressants, anti-psychotics, sedative-hypnotics, and centrally acting opioids. A host of psycho-social factors drive a person to commit suicide and one of the catalysts is over-consumption of alcohol and acute alcohol intoxication. Heavy drinking leads to a loss of inhibitions, impulsive behaviour, poor judgment and a tendency to take risks, all of which might increase the propensity of predisposed individuals to take their own lives.
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Concentration distributions of the drugs most frequently identified in post-mortem femoral blood representing all causes of death.
Med Sci Law
PUBLISHED: 12-23-2009
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Interpreting the concentrations of drugs determined in post-mortem blood is not an easy task owing to poly-drug use, adverse drug-drug interactions, as well as a host of pre-analytical factors and various artefacts in post-mortem toxicology. Highly sensitive and specific methods (GC-FID, GC-NPD. GC-MS and LC-MS) were used to determine the concentrations of drugs in femoral blood from 24,876 autopsies representing all causes of death. Ethanol topped the list of psychoactive substances (N=8108 or 33%) at mean, median and highest concentrations of 1.43 g/L, 1.20 g/L and 8.0 g/L, respectively. In second place was paracetamol (N=2741 or 11%). Amphetamine and cannabis were the major illicit drugs at 13th and 15th positions, respectively. Newer antidepressants, citalopram (no 3), sertraline (no 14), venlafaxine (no 16) were prominent as were sedative-hypnotics, such as diazepam (no 4), zopiclone (no 5) and zolpidem (no 18). This compilation of drugs and their concentration distributions will be useful to identify and flag for a likely overdose or drug-related poisoning death. The drug concentration together with the findings at autopsy and the police report can then be used to reach a conclusion about the cause and manner of death.
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Extracorporeal photo-apheresis for the treatment of steroid-resistant graft versus host disease.
Transfus. Apher. Sci.
PUBLISHED: 10-09-2009
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Acute and chronic graft versus host disease are frequent and potentially severe complications of allogeneic hematopoietic stem cell transplantation and are among the leading causes of non-relapse transplant-related mortality. For patients with steroid refractory disease, prognosis is particularly poor and although a variety of treatment options are available, responses are commonly transient and the side effects often intolerable. Since it was first introduced for the treatment of cutaneous T-cell lymphoma, extracorporeal photo-apheresis has been utilized as an immunomodulatory therapy for certain autoimmune diseases and solid organ transplant rejection. Recently, extracorporeal photo-apheresis has become a promising alternative for patients with graft versus host disease with disabling or potentially lethal complications. Here we review the experience of extracorporeal photo-apheresis for the treatment of steroid refractory acute and chronic graft versus host disease based on the current literature.
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Relationship between blood and urine alcohol concentrations in apprehended drivers who claimed consumption of alcohol after driving with and without supporting evidence.
Forensic Sci. Int.
PUBLISHED: 08-17-2009
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For various reasons, many people suspected of driving under the influence of alcohol (DUIA) are not apprehended sitting behind the wheel, but some time after the driving. This gives them the opportunity to claim they drank alcohol after the time of driving or after they were involved in a road-traffic crash. Alleged post-offence drinking is not easy for the prosecution to disprove, which often means that the DUIA charge is dropped or the person is acquitted if the case goes to trial. The routine practice of sampling and measuring the concentration of alcohol in blood (BAC) and urine (UAC) and calculating urine/blood ratios (UAC/BAC) and the changes in UAC between two successive voids furnishes useful information to support or challenge alleged drinking after driving. We present here a retrospective case series of DUIA offenders (N=40) in half of which there was supporting evidence of an after-drink (eye witness or police reports) and in the other half no such evidence existed apart from the suspects admission. When there was supporting evidence of an after-drink, the UAC/BAC ratio for the first void was close to or less than unity (mean 1.04, median 1.08, range 0.54-1.21) and the UAC increased by 0.21 g/L (range 0.02-0.57) between the two voids. Without any supporting evidence of post-offence drinking the mean UAC/BAC ratio was 1.46 (range 1.35-1.93) for the first void, verifying that absorption and distribution of alcohol in all body fluids and tissues was complete. In these cases, the UAC between successive voids decreased by 0.25 g/L on average (range 0.10-0.49), indicating the post-absorptive phase of the BAC curve. Long experience from investigating claims of post-offence drinking leads us to conclude that in the vast majority of cases this lacks any substance and is simply a last resort by DUIA offenders to evade justice. Unless supporting evidence exists (eye witness, police reports, etc.) of post-offence drinking the courts are encouraged to ignore this defence argument.
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Application of immunotherapy in pediatric leukemia.
Curr Hematol Malig Rep
PUBLISHED: 03-03-2009
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Despite great progress in the curative treatment of leukemia in pediatrics, current therapies are associated with multiple toxicities and the prognosis after relapse is guarded. Novel approaches are needed to overcome resistance to standard therapy and decrease adverse effects. The efficacy of allogeneic stem cell transplantation and the demonstration of a graft-versus-leukemia effect suggest that immune-based therapies can be effective in the treatment of childhood leukemia. Efforts to apply new immunotherapy approaches to the treatment of leukemia in pediatrics have recently begun. The optimal reagents, methods, and regimens have yet to be fully defined. Ongoing clinical trials offer promise in that regard.
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Age and gender differences in blood-alcohol concentration in apprehended drivers in relation to the amounts of alcohol consumed.
Forensic Sci. Int.
PUBLISHED: 01-29-2009
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This article reports the age, gender, and blood-alcohol concentration (BAC) of people apprehended in Sweden for driving under the influence of alcohol (DUIA) over an 8-year period (2000-2007). Duplicate determinations of ethanol were made in venous blood by headspace gas chromatography and results were reported positive at a cut-off concentration of 0.1 g/L (10 mg/100 ml or 0.01 g%). The mean, median and highest BAC was 1.74 g/L, 1.70 g/L and 5.18 g/L, respectively. The vast majority of offenders were men (89.5%) with a mean age of 39.0+/-14.6 y (+/-SD). The women (10.5%) were a few years older 41.8+/-13.6 y (p<0.001). The mean BAC in the men (1.73+/-0.85 g/L) did not differ significantly (p>0.05) from women (1.77+/-0.87 g/L). The youngest offenders aged 15-20 y (N=3513) had a mean BAC of 1.30+/-0.60 g/L (median 1.32), which was significantly less (p<0.001) than people aged 40-50 y (N=6644); mean 1.90 g/L (median 2.0 g/L). In 95 individuals (89 men and 6 women) the BAC exceeded 4.0 g/L, which is a level considered to cause death by acute alcohol poisoning. The Widmark formula was used to calculate that a man (80 kg) with a BAC of 1.7 g/L has 95 g ethanol (approximately 12 units of alcohol) in the body compared with 61 g (approximately 8 units) for a woman (60 kg). This study verifies that the average drunken driver in Sweden is typically a binge drinker and education programs and treatment for alcohol-use disorder might be a more appropriate sanction than the more conventional penalties for alcohol-impaired driving.
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Five-year update on the occurrence of alcohol and other drugs in blood samples from drivers killed in road-traffic crashes in Sweden.
Forensic Sci. Int.
PUBLISHED: 01-14-2009
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According to statistics provided by the Swedish National Road Administration (Vägverket), a total of 1403 drivers were killed in road-traffic crashes in Sweden between 2003 and 2007. Forensic autopsies were performed in approximately 97% of all deaths and specimens of blood and urine were sent for toxicological analysis. In 60% of cases (N=835) the toxicology results were negative and 83% of these victims were men. The blood-alcohol concentration (BAC) was above the legal limit for driving (>0.2g/L) in 22% of cases (N=315) at mean, median and highest concentrations of 1.7 g/L, 1.7 g/L and 4.9 g/L, respectively. The proportions of male to female drivers with BAC>0.2g/L were 93% vs 7% compared with 83% vs 17% for those with drugs other than alcohol in blood. Drivers with a punishable BAC were over-represented in single vehicle crashes compared with multiple vehicle crashes (67% vs 33%). The opposite held for drivers who had taken a prescription drug (39% vs 61%) and also for drug-negative cases (31% vs 69%). Drugs other than alcohol were identified in 253 cases (18%); illicit drugs only in 39 cases (2.8%), both licit and illicit in 28 cases (2.0%) and in 186 cases (13.3%) one or more therapeutic drugs were present. Amphetamine was the most common illicit drug identified at mean, median and highest concentrations of 1.5mg/L, 1.1mg/L and 5.0mg/L, respectively (N=39). Blood specimens contained a wide spectrum of pharmaceutical products (mean 2.4 drugs/person), comprising sedative-hypnotics (N=93), opiates/opioids (N=69) as well non-scheduled substances, such as paracetamol (N=78) and antidepressants (N=93). The concentrations of these substances in blood were mostly in the therapeutic range. Despite an appreciable increase (12-fold) in number of arrests made by the police for drug-impaired driving after a zero-tolerance law was introduced (July 1999), alcohol still remains the psychoactive substance most frequently identified in the blood of drivers killed in road-traffic crashes.
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Restricted cell surface expression of receptor tyrosine kinase ROR1 in pediatric B-lineage acute lymphoblastic leukemia suggests targetability with therapeutic monoclonal antibodies.
PLoS ONE
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Despite high cure rates for pediatric B-lineage acute lymphoblastic leukemia (B-ALL), short-term and long-term toxicities and chemoresistance are shortcomings of standard chemotherapy. Immunotherapy and chemoimmunotherapy based on monoclonal antibodies (mAbs) that target cell surface antigens with restricted expression in pediatric B-ALL may offer the potential to reduce toxicities and prevent or overcome chemoresistance. The receptor tyrosine kinase ROR1 has emerged as a candidate for mAb targeting in select B-cell malignancies.
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Concentrations of alprazolam in blood from impaired drivers and forensic autopsies were not much different but showed a high prevalence of co-ingested illicit drugs.
J. Psychopharmacol. (Oxford)
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Alprazolam is a benzodiazepine anxiolytic widely prescribed for treatment of panic-disorder and social phobias, although this medication is also subject to abuse. In this paper, the concentrations of alprazolam in venous blood samples from impaired drivers were compared with femoral blood samples from forensic autopsies classified as intoxication or other causes of death (e.g. natural, trauma). After liquid-liquid extraction (n-butyl acetate) alprazolam was determined in blood by capillary gas chromatography with a nitrogen-phosphorous detector. The mean (median) and range of alprazolam concentrations in blood from impaired drivers (n = 773) were 0.08 mg/L (0.05 mg/L) and 0.02-3.9 mg/L, respectively. Many traffic offenders had co-ingested ethanol (13%), amphetamine (46%), cannabis (32%), or heroin (14%), as well as other drugs. In deaths attributed to drug intoxication, the mean (median) and range of alprazolam concentrations in blood (n = 438) were 0.10 mg/L (0.06 mg/L) and 0.02-1.6 mg/L, respectively, which were not much different from other causes of death (n = 278); 0.08 mg/L (0.05 mg/L) and 0.02-0.9 mg/L. Median concentrations of alprazolam in blood from living and deceased persons did not seem to depend on the number of co-ingested substances. The result of this pharmacoepidemiological study suggests that alprazolam is a fairly innocent drug when used as monotherapy, but toxicity problems arise when co-ingested with illicit drugs and/or psychoactive medication.
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Anti-CD22-chimeric antigen receptors targeting B-cell precursor acute lymphoblastic leukemia.
Blood
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Immune targeting of B-cell malignancies using chimeric antigen receptors (CARs) is a promising new approach, but critical factors impacting CAR efficacy remain unclear. To test the suitability of targeting CD22 on precursor B-cell acute lymphoblastic leukemia (BCP-ALL), lymphoblasts from 111 patients with BCP-ALL were assayed for CD22 expression and all were found to be CD22-positive, with median CD22 expression levels of 3500 sites/cell. Three distinct binding domains targeting CD22 were fused to various TCR signaling domains ± an IgG heavy chain constant domain (CH2CH3) to create a series of vector constructs suitable to delineate optimal CAR configuration. CARs derived from the m971 anti-CD22 mAb, which targets a proximal CD22 epitope demonstrated superior antileukemic activity compared with those incorporating other binding domains, and addition of a 4-1BB signaling domain to CD28.CD3 constructs diminished potency, whereas increasing affinity of the anti-CD22 binding motif, and extending the CD22 binding domain away from the membrane via CH2CH3 had no effect. We conclude that second-generation m971 mAb-derived anti-CD22 CARs are promising novel therapeutics that should be tested in BCP-ALL.
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What non-alcohol drugs are used by drinking drivers in Sweden? Toxicological results from ten years of forensic blood samples.
J Safety Res
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Using a forensic toxicology database (TOXBASE), the toxicological results from 10 years of forensic blood samples from people arrested for driving under the influence of alcohol and/or other drugs were reviewed.
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Gene therapy for adenosine deaminase-deficient severe combined immune deficiency: clinical comparison of retroviral vectors and treatment plans.
Blood
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We conducted a gene therapy trial in 10 patients with adenosine deaminase (ADA)-deficient severe combined immunodeficiency using 2 slightly different retroviral vectors for the transduction of patients bone marrow CD34(+) cells. Four subjects were treated without pretransplantation cytoreduction and remained on ADA enzyme-replacement therapy (ERT) throughout the procedure. Only transient (months), low-level (< 0.01%) gene marking was observed in PBMCs of 2 older subjects (15 and 20 years of age), whereas some gene marking of PBMC has persisted for the past 9 years in 2 younger subjects (4 and 6 years). Six additional subjects were treated using the same gene transfer protocol, but after withdrawal of ERT and administration of low-dose busulfan (65-90 mg/m(2)). Three of these remain well, off ERT (5, 4, and 3 years postprocedure), with gene marking in PBMC of 1%-10%, and ADA enzyme expression in PBMC near or in the normal range. Two subjects were restarted on ERT because of poor gene marking and immune recovery, and one had a subsequent allogeneic hematopoietic stem cell transplantation. These studies directly demonstrate the importance of providing nonmyeloablative pretransplantation conditioning to achieve therapeutic benefits with gene therapy for ADA-deficient severe combined immunodeficiency.
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Pretransplant MRD: the light is yellow, not red.
Blood
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In the study reported in this issue of Blood by Leung et al, detectable minimal residual disease (MRD) before hematopoietic stem cell transplantation (HSCT) was found to be prognostic for outcome, but did not prevent cure for children with acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML).
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Concentrations of zolpidem and zopiclone in venous blood samples from impaired drivers compared with femoral blood from forensic autopsies.
Forensic Sci. Int.
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The concentrations of zolpidem and zopiclone were determined in peripheral blood samples in two forensic materials collected over a 10-year period (2001-2010). The z-hypnotics were determined in venous blood from living subjects (impaired drivers) and in femoral blood from deceased persons (forensic autopsies), with the latter classified as intoxication or other causes of death. The z-hypnotics were determined in blood by capillary column gas chromatography (GC) with a nitrogen-phosphorous (N-P) detector after solvent extraction with n-butyl acetate. The analytical limit of quantitation (LOQ) was 0.02 mg/L for zopiclone and 0.05 mg/L for zolpidem and these have remained unchanged throughout the study. When death was attributed to drug intoxication (N=918), the median concentration of zopiclone in blood was 0.20 mg/L compared with 0.06 mg/L for other causes of death (N=1215) and 0.07 mg/L in traffic offenders (N=691) (p<0.001). Likewise, a higher median concentration (0.30 mg/L) was found in intoxication deaths involving zolpidem (N=357) compared with 0.13 mg/L for other causes of death (N=397) or 0.19 mg/L in impaired drivers (N=837) (p<0.001). Median concentration in blood of both z-hypnotics were appreciably higher in intoxication deaths when no other substances were identified; 0 70 mg/L (N=12) for zopiclone and 1.35 mg/L (N=12) for zolpidem. The median concentrations of z-hypnotics in blood decreased as the number of co-ingested substances increased for intoxication deaths but not other causes of death. The most prevalent co-ingested substances were ethanol in autopsy cases and diazepam in the motorists. This large compilation of forensic cases should prove useful when toxicologists are required to interpret concentrations of z-hypnotics in blood samples in relation to cause of death.
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Immunotoxin resistance via reversible methylation of the DPH4 promoter is a unique survival strategy.
Proc. Natl. Acad. Sci. U.S.A.
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HA22 is a recombinant immunotoxin composed of an anti-CD22 Fv fused to a portion of Pseudomonas exotoxin A. HA22 produced a high rate of complete remissions in drug-resistant hairy cell leukemia and has a lower response rate in pediatric acute lymphoblastic leukemia (ALL). To understand why patients with ALL have poorer responses, we isolated an ALL cell line that is resistant to killing by HA22. The resistance is unstable; without HA22 the cells revert to HA22 sensitivity in 4 mo. We showed that in the resistant cell line, HA22 is unable to ADP ribosylate and inactivate elongation factor-2 (EF2), owing to a low level of DPH4 mRNA and protein, which prevents diphthamide biosynthesis and renders EF2 refractory to HA22. Analysis of the promoter region of the DPH4 gene shows that the CpG island was hypomethylated in the HA22-sensitive cells, heavily methylated in the resistant cells, and reverted to low methylation in the revertant cells. Our data show that immunotoxin resistance is associated with reversible CpG island methylation and silencing of DPH4 gene transcription. Incubation of sensitive cells with the methylation inhibitor 5-azacytidine prevented the emergence of resistant cells, suggesting that this agent in combination with HA22 may be useful in the treatment of some cases of ALL.
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Bone marrow homing and engraftment of human hematopoietic stem and progenitor cells is mediated by a polarized membrane domain.
Blood
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Manipulation of hematopoietic stem/progenitor cells (HSPCs) ex vivo is of clinical importance for stem cell expansion and gene therapy applications. However, most cultured HSPCs are actively cycling, and show a homing and engraftment defect compared with the predominantly quiescent noncultured HSPCs. We previously showed that HSPCs make contact with osteoblasts in vitro via a polarized membrane domain enriched in adhesion molecules such as tetraspanins. Here we show that increased cell cycling during ex vivo culture of HSPCs resulted in disruption of this membrane domain, as evidenced by disruption of polarity of the tetraspanin CD82. Chemical disruption or antibody-mediated blocking of CD82 on noncultured HSPCs resulted in decreased stromal cell adhesion, homing, and engraftment in nonobese diabetic/severe combined immunodeficiency IL-2?(null) (NSG) mice compared with HSPCs with an intact domain. Most leukemic blasts were actively cycling and correspondingly displayed a loss of domain polarity and decreased homing in NSG mice compared with normal HSPCs. We conclude that quiescent cells, unlike actively cycling cells, display a polarized membrane domain enriched in tetraspanins that mediates homing and engraftment, providing a mechanistic explanation for the homing/engraftment defect of cycling cells and a potential new therapeutic target to enhance engraftment.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.