Impact of hydroxyurea on clinical events in the BABY HUG trial
Files, Beatrice A.; Luo, Zhaoyu; Miller, Scott T.; Kalpatthi, Ram; Iyer, Rathi; Seaman, Phillip; Lebensburger, Jeffrey; Alvarez, Ofelia; Thompson, Bruce; Ware, Russell E.; Wang, Winfred C.
2012-01-01
The Pediatric Hydroxyurea Phase 3 Clinical Trial (BABY HUG) was a phase 3 multicenter, randomized, double-blind, placebo-controlled clinical trial of hydroxyurea in infants (beginning at 9-18 months of age) with sickle cell anemia. An important secondary objective of this study was to compare clinical events between the hydroxyurea and placebo groups. One hundred and ninety-three subjects were randomized to hydroxyurea (20 mg/kg/d) or placebo; there were 374 patient-years of on-study observation. Hydroxyurea was associated with statistically significantly lower rates of initial and recurrent episodes of pain, dactylitis, acute chest syndrome, and hospitalization; even infants who were asymptomatic at enrollment had less dactylitis as well as fewer hospitalizations and transfusions if treated with hydroxyurea. Despite expected mild myelosuppression, hydroxyurea was not associated with an increased risk of bacteremia or serious infection. These data provide important safety and efficacy information for clinicians considering hydroxyurea therapy for very young children with sickle cell anemia. This clinical trial is registered with the National Institutes of Health (NCT00006400, www.clinicaltrials.gov). PMID:22915643
Massive Accidental Overdose of Hydroxyurea in a Young Child with Sickle Cell Anemia
Miller, Scott T.; Rey, Kathy; He, Jin; Flanagan, Jonathan; Fish, Billie J.; Rogers, Zora R.; Wang, Winfred C.; Ware, Russell E.
2011-01-01
The Pediatric Hydroxyurea Phase III Clinical Trial (BABY HUG) confirmed safety and efficacy of hydroxyurea therapy for infants with sickle cell anemia. Treatment was associated with reduction in rates of pain, acute chest syndrome, hospitalizations and blood transfusions; improved hematologic values; and, perhaps, preservation of organ function. During the study, a two year-old ingested at one time an entire 35-day supply of hydroxyurea (612 mg/kg body-weight). Despite a serum level of 7,756 μM four hours post-ingestion, the only toxicity was transient mild myelosuppression. With wider usage of hydroxyurea anticipated, conservative management of future overdoses seems reasonable. (ClinicalTrials.gov NCT00006400) PMID:21744485
Hydroxyurea for sickle cell anemia: What have we learned and what questions still remain?
McGann, Patrick T.; Ware, Russell E.
2011-01-01
Purpose of review Sickle cell anemia (SCA) is a well-characterized severe hematological disorder with substantial morbidity and early mortality. Hydroxyurea is a potent inducer of fetal hemoglobin, and evidence over the past 25 years has documented its laboratory and clinical efficacy for both adults and children with SCA. Recent findings The Phase III study of hydroxyurea in infants (BABY HUG) has just been completed and preliminary results indicate equivocal benefits for organ protection during the two-year treatment period, but significant benefits for pain, acute chest syndrome, hospitalizations, and transfusions. Three new reports document the benefits of hydroxyurea on reducing mortality in SCA: two adult trials (LaSHS and MSH) and one pediatric study (Brazilian cohort). Recent results from the HUSTLE protocol suggest minimal genotoxicity or carcinogenicity with long-term hydroxyurea exposure. Summary The potential utility of hydroxyurea for all patients with SCA is clear and indisputable. With decades of accumulated evidence and documented efficacy with an acceptable long-term safety profile, it is time to consider hydroxyurea treatment the standard of care for all young patients with SCA. Exporting our knowledge and experience with hydroxyurea to developing nations with large medical burdens from SCA can help relieve global suffering from this condition. PMID:21372708
Tshilolo, Léon; Santos, Brigida; Tomlinson, George A.; Stuber, Susan; Latham, Teresa; Aygun, Banu; Obaro, Stephen K.; Olupot‐Olupot, Peter; Williams, Thomas N.; Odame, Isaac; Ware, Russell E.
2015-01-01
Background Sickle cell anemia (SCA) is an inherited hematological disorder that causes a large but neglected global health burden, particularly in Africa. Hydroxyurea represents the only available disease‐modifying therapy for SCA, and has proven safety and efficacy in high‐resource countries. In sub‐Saharan Africa, there is minimal use of hydroxyurea, due to lack of data, absence of evidence‐based guidelines, and inexperience among healthcare providers. Procedure A partnership was established between investigators in North America and sub‐Saharan Africa, to develop a prospective multicenter research protocol designed to provide data on the safety, feasibility, and benefits of hydroxyurea for children with SCA. Results The Realizing Effectiveness Across Continents with Hydroxyurea (REACH, ClinicalTrials.gov NCT01966731) trial is a prospective, phase I/II open‐label dose escalation study of hydroxyurea that will treat a total of 600 children age 1–10 years with SCA: 150 at each of four different clinical sites within sub‐Saharan Africa (Angola, Democratic Republic of Congo, Kenya, and Uganda). The primary study endpoint will be severe hematological toxicities that occur during the fixed‐dose treatment phase. REACH has an adaptive statistical design that allows for careful assessment of toxicities to accurately identify a safe hydroxyurea dose. Conclusions REACH will provide data that address critical gaps in knowledge for the treatment of SCA in sub‐Saharan Africa. By developing local expertise with the use of hydroxyurea and helping to establish treatment guidelines, the REACH trial results will have the potential to transform care for children with SCA in Africa. Pediatr Blood Cancer © 2015 Wiley Periodicals, Inc. PMID:26275071
McGann, Patrick T; Tshilolo, Léon; Santos, Brigida; Tomlinson, George A; Stuber, Susan; Latham, Teresa; Aygun, Banu; Obaro, Stephen K; Olupot-Olupot, Peter; Williams, Thomas N; Odame, Isaac; Ware, Russell E
2016-01-01
Sickle cell anemia (SCA) is an inherited hematological disorder that causes a large but neglected global health burden, particularly in Africa. Hydroxyurea represents the only available disease-modifying therapy for SCA, and has proven safety and efficacy in high-resource countries. In sub-Saharan Africa, there is minimal use of hydroxyurea, due to lack of data, absence of evidence-based guidelines, and inexperience among healthcare providers. A partnership was established between investigators in North America and sub-Saharan Africa, to develop a prospective multicenter research protocol designed to provide data on the safety, feasibility, and benefits of hydroxyurea for children with SCA. The Realizing Effectiveness Across Continents with Hydroxyurea (REACH, ClinicalTrials.gov NCT01966731) trial is a prospective, phase I/II open-label dose escalation study of hydroxyurea that will treat a total of 600 children age 1-10 years with SCA: 150 at each of four different clinical sites within sub-Saharan Africa (Angola, Democratic Republic of Congo, Kenya, and Uganda). The primary study endpoint will be severe hematological toxicities that occur during the fixed-dose treatment phase. REACH has an adaptive statistical design that allows for careful assessment of toxicities to accurately identify a safe hydroxyurea dose. REACH will provide data that address critical gaps in knowledge for the treatment of SCA in sub-Saharan Africa. By developing local expertise with the use of hydroxyurea and helping to establish treatment guidelines, the REACH trial results will have the potential to transform care for children with SCA in Africa. © 2015 The Authors. Pediatric Blood & Cancer Published by Wiley Periodicals, Inc.
Summarell, Carly C Ginter
2016-01-01
Hydroxyurea is an excellent therapeutic agent for the pharmacological induction of HbF in patients with sickle cell disease (SCD). However, all completed clinical trials of hydroxyurea have excluded patients with hemoglobin SC (HbSC) disease. HbSC differs significantly in pathophysiology from HbSS, as HbC does not sickle, but instead causes cellular dehydration which potentiates sickling of HbS. Many severely affected HbSC patients have been placed on hydroxyurea on a case by case basis, but there are no large scale prospective data on safety or efficacy of hydroxyurea in this subset of patients with SCD. Here, we report a case series of 14 pediatric patients with HbSC treated to maximum tolerated dose (MTD) with hydroxyurea. Those who failed to show clinical improvement after at least six months at MTD were offered phlebotomy in addition to hydroxyurea. Five out of 11 patients with HbSC who achieved MTD failed to demonstrate clinical improvement on hydroxyurea. Of the four placed on dual hydroxyurea and phlebotomy therapy, all showed at least partial clinical improvement. Percent dense red blood cells (%DRBC) were measured via an ADVIA hematology analyzer. A marked rise in percent dense cells preceded clinical complications in three patients. Dual therapy with hydroxyurea and phlebotomy may be an effective approach to patients with HbSC that do not experience improvement with hydroxyurea alone. Monitoring of %DRBC may predict adverse events and aid in assessing hydroxyurea compliance. Large scale clinical trials are needed to evaluate the safety and efficacy of hydroxyurea and hydroxyurea with phlebotomy in patients with HbSC disease. PMID:26993671
Summarell, Carly C Ginter; Sheehan, Vivien A
2016-04-01
Hydroxyurea is an excellent therapeutic agent for the pharmacological induction of HbF in patients with sickle cell disease (SCD). However, all completed clinical trials of hydroxyurea have excluded patients with hemoglobin SC (HbSC) disease. HbSC differs significantly in pathophysiology from HbSS, as HbC does not sickle, but instead causes cellular dehydration which potentiates sickling of HbS. Many severely affected HbSC patients have been placed on hydroxyurea on a case by case basis, but there are no large scale prospective data on safety or efficacy of hydroxyurea in this subset of patients with SCD. Here, we report a case series of 14 pediatric patients with HbSC treated to maximum tolerated dose (MTD) with hydroxyurea. Those who failed to show clinical improvement after at least six months at MTD were offered phlebotomy in addition to hydroxyurea. Five out of 11 patients with HbSC who achieved MTD failed to demonstrate clinical improvement on hydroxyurea. Of the four placed on dual hydroxyurea and phlebotomy therapy, all showed at least partial clinical improvement. Percent dense red blood cells (%DRBC) were measured via an ADVIA hematology analyzer. A marked rise in percent dense cells preceded clinical complications in three patients. Dual therapy with hydroxyurea and phlebotomy may be an effective approach to patients with HbSC that do not experience improvement with hydroxyurea alone. Monitoring of %DRBC may predict adverse events and aid in assessing hydroxyurea compliance. Large scale clinical trials are needed to evaluate the safety and efficacy of hydroxyurea and hydroxyurea with phlebotomy in patients with HbSC disease. © 2016 by the Society for Experimental Biology and Medicine.
Effects of hydroxyurea treatment for patients with hemoglobin SC disease.
Luchtman-Jones, Lori; Pressel, Sara; Hilliard, Lee; Brown, R Clark; Smith, Mary G; Thompson, Alexis A; Lee, Margaret T; Rothman, Jennifer; Rogers, Zora R; Owen, William; Imran, Hamayun; Thornburg, Courtney; Kwiatkowski, Janet L; Aygun, Banu; Nelson, Stephen; Roberts, Carla; Gauger, Cynthia; Piccone, Connie; Kalfa, Theodosia; Alvarez, Ofelia; Hassell, Kathryn; Davis, Barry R; Ware, Russell E
2016-02-01
Although hemoglobin SC (HbSC) disease is usually considered less severe than sickle cell anemia (SCA), which includes HbSS and HbS/β(0) -thalassemia genotypes, many patients with HbSC experience severe disease complications, including vaso-occlusive pain, acute chest syndrome, avascular necrosis, retinopathy, and poor quality of life. Fully 20 years after the clinical and laboratory efficacy of hydroxyurea was proven in adult SCA patients, the safety and utility of hydroxyurea treatment for HbSC patients remain unclear. Recent NHLBI evidence-based guidelines highlight this as a critical knowledge gap, noting HbSC accounts for ∼30% of sickle cell patients within the United States. To date, only 5 publications have reported short-term, incomplete, or conflicting laboratory and clinical outcomes of hydroxyurea treatment in a total of 71 adults and children with HbSC. We now report on a cohort of 133 adult and pediatric HbSC patients who received hydroxyurea, typically for recurrent vaso-occlusive pain. Hydroxyurea treatment was associated with a stable hemoglobin concentration; increased fetal hemoglobin (HbF) and mean corpuscular volume (MCV); and reduced white blood cell count (WBC), absolute neutrophil count (ANC), and absolute reticulocyte count (ARC). Reversible cytopenias occurred in 22% of patients, primarily neutropenia and thrombocytopenia. Painful events were reduced with hydroxyurea, more in patients >15 years old. These multicenter data support the safety and potentially salutary effects of hydroxyurea treatment for HbSC disease; however, a multicenter, placebo-controlled, Phase 3 clinical trial is needed to determine if hydroxyurea therapy has efficacy for patients with HbSC disease. © 2015 Wiley Periodicals, Inc.
Marahatta, Anu; Megaraj, Vandana; McGann, Patrick T; Ware, Russell E; Setchell, Kenneth D R
2016-12-01
Sickle cell anemia (SCA) is a life-threatening blood disorder characterized by the presence of sickle-shaped erythrocytes. Hydroxyurea is currently the only US Food and Drug Administration-approved treatment and there is a need for a convenient method to monitor compliance and hydroxyurea concentrations, especially in pediatric SCA patients. We describe a novel approach to the determination of hydroxyurea concentrations in dried whole blood collected on DMPK-C cards or volumetric absorptive microsampling (VAMS) devices. Hydroxyurea was quantified by electrospray ionization LC-MS/MS using [ 13 C 15 N 2 ]hydroxyurea as the internal standard. Calibrators were prepared in whole blood applied to DMPK-C cards or VAMS devices. Calibration curves for blood hydroxyurea measured from DMPK-C cards and VAMS devices were linear over the range 0.5-60 μg/mL. Interassay and intraassay CVs were <15% for blood collected by both methods, and the limit of detection was 5 ng/mL. Whole blood hydroxyurea was stable for up to 60 days on DMPK-C cards and VAMS devices when frozen at -20 °C or -80 °C. Whole blood hydroxyurea concentrations in samples collected on DMPK-C cards or VAMS devices from SCA patients were in close agreement. This tandem mass spectrometry method permits measurement of hydroxyurea concentrations in small volumes of dried blood applied to either DMPK-C cards or VAMS devices with comparable performance. This method for measuring hydroxyurea from dried blood permits the evaluation of therapeutic drug monitoring, individual pharmacokinetics, and medication adherence using heel/finger-prick samples from pediatric patients with SCA treated with hydroxyurea. © 2016 American Association for Clinical Chemistry.
Hydroxyurea in Pediatric Patients With Sickle Cell Disease: What Nurses Need to Know.
Rees, Allison L
2016-09-01
Sickle cell disease (SCD) is an inherited disorder in which sickled red blood cells occlude the small vessels of the body, reducing oxygen delivery to tissues and ultimately negatively affecting many of the body's major organs. Hydroxyurea has proven beneficial in the treatment of SCD and prevention of disease-related complications. The 2014 guidelines put forth by the National Heart, Lung, and Blood Institute recommend hydroxyurea treatment in infants 9 months and older, children, and adolescents with SCD-SS or SCD-Sβ(0) thalassemia regardless of clinical severity. This is a change from the 2002 guidelines in which hydroxyurea was recommended for adolescents and children with SCD-SS or SCD-Sβ(0) thalassemia with frequent episodes of pain, a history of acute chest syndrome, severe and symptomatic anemia or other severe vaso-occlusive events. Nurses play a critical role in working with patients and families to provide education, guidance, and support to improve compliance to mitigate the long-term effects of SCD. © 2015 by Association of Pediatric Hematology/Oncology Nurses.
Green, Nancy S.; Ender, Katherine L.; Pashankar, Farzana; Driscoll, Catherine; Giardina, Patricia J.; Mullen, Craig A.; Clark, Lorraine N.; Manwani, Deepa; Crotty, Jennifer; Kisselev, Sergey; Neville, Kathleen A.; Hoppe, Carolyn; Barral, Sandra
2013-01-01
Background Fetal hemoglobin level is a heritable complex trait that strongly correlates swith the clinical severity of sickle cell disease. Only few genetic loci have been identified as robustly associated with fetal hemoglobin in patients with sickle cell disease, primarily adults. The sole approved pharmacologic therapy for this disease is hydroxyurea, with effects largely attributable to induction of fetal hemoglobin. Methodology/Principal Findings In a multi-site observational analysis of children with sickle cell disease, candidate single nucleotide polymorphisms associated with baseline fetal hemoglobin levels in adult sickle cell disease were examined in children at baseline and induced by hydroxyurea therapy. For baseline levels, single marker analysis demonstrated significant association with BCL11A and the beta and epsilon globin loci (HBB and HBE, respectively), with an additive attributable variance from these loci of 23%. Among a subset of children on hydroxyurea, baseline fetal hemoglobin levels explained 33% of the variance in induced levels. The variant in HBE accounted for an additional 13% of the variance in induced levels, while variants in the HBB and BCL11A loci did not contribute beyond baseline levels. Conclusions/Significance These findings clarify the overlap between baseline and hydroxyurea-induced fetal hemoglobin levels in pediatric disease. Studies assessing influences of specific sequence variants in these and other genetic loci in larger populations and in unusual hydroxyurea responders are needed to further understand the maintenance and therapeutic induction of fetal hemoglobin in pediatric sickle cell disease. PMID:23409025
Quarmyne, Maa-Ohui; Dong, Wei; Theodore, Rodney; Anand, Sonia; Barry, Vaughn; Adisa, Olufolake; Buchanan, Iris D.; Bost, James; Brown, Robert C.; Joiner, Clinton H.; Lane, Peter A.
2016-01-01
The clinical efficacy of hydroxyurea in patients with sickle cell anemia (SCA) has been well established. However, data about its clinical effectiveness in practice is limited. We evaluated the clinical effectiveness of hydroxyurea in a large pediatric population using a retrospective cohort, pre-post treatment study design to control for disease severity selection bias. The cohort included children with SCA (SS, S β 0thalassemia) who received care at Children's Healthcare of Atlanta (CHOA) and who initiated hydroxyurea in 2009-2011. Children on chronic transfusions, or children with inadequate follow up data and/or children who had taken hydroxyurea in the 3 years prior were excluded. For each patient, healthcare utilization, laboratory values and clinical outcomes for the 2-year period prior to hydroxyurea initiation were compared to those 2 years after initiation. Of 211 children with SCA who initiated hydroxyurea in 2009-2011, 134 met eligibility criteria. After initiation of hydroxyurea, rates of hospitalizations, pain encounters, and emergency department visits were reduced by 47% (<0.0001), 36% (p=0.0001) and 43% (p<0.0001), respectively. Average hemoglobin levels increased by 0.7g/dl (p<0.0001). Hydroxyurea effectiveness was similar across gender, insurance types and age, although there was a slightly greater reduction in hospitalizations in younger children. PMID:27761932
Quarmyne, Maa-Ohui; Dong, Wei; Theodore, Rodney; Anand, Sonia; Barry, Vaughn; Adisa, Olufolake; Buchanan, Iris D; Bost, James; Brown, Robert C; Joiner, Clinton H; Lane, Peter A
2017-01-01
The clinical efficacy of hydroxyurea in patients with sickle cell anemia (SCA) has been well established. However, data about its clinical effectiveness in practice is limited. We evaluated the clinical effectiveness of hydroxyurea in a large pediatric population using a retrospective cohort, pre-post treatment study design to control for disease severity selection bias. The cohort included children with SCA (SS, Sβ 0 thalassemia) who received care at Children's Healthcare of Atlanta (CHOA) and who initiated hydroxyurea in 2009-2011. Children on chronic transfusions, or children with inadequate follow up data and/or children who had taken hydroxyurea in the 3 years prior were excluded. For each patient healthcare utilization, laboratory values, and clinical outcomes for the 2-year period prior to hydroxyurea initiation were compared to those 2 years after initiation. Of 211 children with SCA who initiated hydroxyurea in 2009-2011, 134 met eligibility criteria. After initiation of hydroxyurea, rates of hospitalizations, pain encounters, and emergency department visits were reduced by 47% (<0.0001), 36% (P = 0.0001) and 43% (P < 0.0001), respectively. Average hemoglobin levels increased by 0.7 g/dl (P < 0.0001). Hydroxyurea effectiveness was similar across gender, insurance types and age, although there was a slightly greater reduction in hospitalizations in younger children. Am. J. Hematol. 92:77-81, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Immunologic effects of hydroxyurea in sickle cell anemia.
Lederman, Howard M; Connolly, Margaret A; Kalpatthi, Ram; Ware, Russell E; Wang, Winfred C; Luchtman-Jones, Lori; Waclawiw, Myron; Goldsmith, Jonathan C; Swift, Andrea; Casella, James F
2014-10-01
Susceptibility to encapsulated bacteria is well known in sickle cell disease (SCD). Hydroxyurea use is common in adults and children with SCD, but little is known about hydroxyurea's effects on immune function in SCD. Because hydroxyurea inhibits ribonucleotide reductase, causing cell cycle arrest at the G1-S interface, we postulated that hydroxyurea might delay transition from naive to memory T cells, with inhibition of immunologic maturation and vaccine responses. T-cell subsets, naive and memory T cells, and antibody responses to pneumococcal and measles, mumps, and rubella vaccines were measured among participants in a multicenter, randomized, double-blind, placebo-controlled trial of hydroxyurea in infants and young children with SCD (BABY HUG). Compared with placebo, hydroxyurea treatment resulted in significantly lower total lymphocyte, CD4, and memory T-cell counts; however, these numbers were still within the range of historical healthy controls. Antibody responses to pneumococcal vaccination were not affected, but a delay in achieving protective measles antibody levels occurred in the hydroxyurea group. Antibody levels to measles, mumps, and rubella showed no differences between groups at exit, indicating that effective immunization can be achieved despite hydroxyurea use. Hydroxyurea does not appear to have significant deleterious effects on the immune function of infants and children with SCD. Additional assessments of lymphocyte parameters of hydroxyurea-treated children may be warranted. No changes in current immunization schedules are recommended; however, for endemic disease or epidemics, adherence to accelerated immunization schedules for the measles, mumps, and rubella vaccine should be reinforced. Copyright © 2014 by the American Academy of Pediatrics.
Isotope-dilution gas chromatography-mass spectrometry method for the analysis of hydroxyurea.
Garg, Uttam; Scott, David; Frazee, Clint; Kearns, Gregory; Neville, Kathleen
2015-06-01
Hydroxyurea is used in the treatment of various malignancies and sickle cell disease. There are limited studies on the pharmacokinetics of hydroxyurea, particularly in pediatric patients. An accurate, precise, and sensitive method is needed to support such studies and to monitor therapeutic adherence. We describe a novel gas chromatography-mass spectrometry (GC-MS) method for the determination of hydroxyurea concentration in plasma using stable labeled hydroxyurea C N2 as an internal standard. The method involved an organic extraction followed by the preparation of trimethylsilyl (TMS) derivatives of hydroxyurea for GC-MS selected ion-monitoring analysis. The following mass-to-charge (m/z) ratio ions for silated hydroxyurea and hydroxyurea C N2 were monitored: hydroxyurea-quantitative ion 277, qualifier ions 292 and 249; hydroxyurea C N2-quantitative ion 280, qualifier ion 295. This method was evaluated for reportable range, accuracy, within-run and between-run imprecisions, and limits of quantification. The reportable range for the method was 0.1-100 mcg/mL. All results were accurate within an allowable error of 15%. Within-run and between-run imprecisions were <15%. Samples were stable for at least 4 hours at room temperature, 2 months at -20°C, and 6 months at -70°C, and after 3 freeze/thaw cycles. Extraction efficiency for 1-, 5-, 10-, and 50-mcg/mL samples averaged 2.2%, 1.8%, 1.6%, and 1.4%, respectively. The isotope-dilution GC-MS method for analysis of hydroxyurea described here is accurate, sensitive, precise, and robust. Its characteristics make the method suitable for supporting pharmacokinetic studies and/or clinical therapeutic monitoring.
Sheehan, Vivien A; Crosby, Jacy R; Sabo, Aniko; Mortier, Nicole A; Howard, Thad A; Muzny, Donna M; Dugan-Perez, Shannon; Aygun, Banu; Nottage, Kerri A; Boerwinkle, Eric; Gibbs, Richard A; Ware, Russell E; Flanagan, Jonathan M
2014-01-01
Hydroxyurea has proven efficacy in children and adults with sickle cell anemia (SCA), but with considerable inter-individual variability in the amount of fetal hemoglobin (HbF) produced. Sibling and twin studies indicate that some of that drug response variation is heritable. To test the hypothesis that genetic modifiers influence pharmacological induction of HbF, we investigated phenotype-genotype associations using whole exome sequencing of children with SCA treated prospectively with hydroxyurea to maximum tolerated dose (MTD). We analyzed 171 unrelated patients enrolled in two prospective clinical trials, all treated with dose escalation to MTD. We examined two MTD drug response phenotypes: HbF (final %HbF minus baseline %HbF), and final %HbF. Analyzing individual genetic variants, we identified multiple low frequency and common variants associated with HbF induction by hydroxyurea. A validation cohort of 130 pediatric sickle cell patients treated to MTD with hydroxyurea was genotyped for 13 non-synonymous variants with the strongest association with HbF response to hydroxyurea in the discovery cohort. A coding variant in Spalt-like transcription factor, or SALL2, was associated with higher final HbF in this second independent replication sample and SALL2 represents an outstanding novel candidate gene for further investigation. These findings may help focus future functional studies and provide new insights into the pharmacological HbF upregulation by hydroxyurea in patients with SCA.
Hydroxyurea is associated with lower prevalence of albuminuria in adults with sickle cell disease
Laurin, Louis-Philippe; Nachman, Patrick H.; Desai, Payal C.; Ataga, Kenneth I.; Derebail, Vimal K.
2014-01-01
Background Albuminuria is an early manifestation of sickle cell nephropathy. Prior small case series suggests benefit of hydroxyurea in reducing albuminuria, with a similar trend noted in pediatric studies. We aimed to comprehensively evaluate hydroxyurea use and prevalence of albuminuria in adult sickle cell patients. Methods We performed a cross-sectional study of 149 adult patients followed between 2000 and 2011 in a comprehensive sickle cell clinic. All patients were assessed for albuminuria either by direct measurement or by urinary chemical strip (dipstick) testing. Urinary albumin-to-creatinine ratios (UACRs) were available for 112 patients. Hydroxyurea exposure was defined as ≥3 months of therapy before the assessment of albuminuria. Albuminuria was defined as either UACR ≥30 mg/g or ≥1+ proteinuria on two separate dipsticks. We constructed a multivariate logistic regression model to assess the association between hydroxyurea and albuminuria. Results The prevalence of albuminuria was lower among patients on hydroxyurea (34.7 versus 55.4%; P = 0.01) as was median albumin excretion (17.9 versus 40.5 mg/g; P = 0.04). In multivariate analysis, hydroxyurea was associated with a lower likelihood of albuminuria (odds ratio 0.28, 95% CI: 0.11–0.75, P = 0.01), adjusting for age, angiotensin-converting enzyme inhibitor/angiotensin receptor blocker use, tricuspid regurgitant jet velocity, hypertension and acute chest syndrome. Conclusions In our population of sickle cell patients, those using hydroxyurea were less than one-third as likely to exhibit albuminuria. Hydroxyurea use may prevent development of overt nephropathy or the progression of sickle cell disease nephropathy to end-stage renal disease, and its use for this indication merits further investigation. PMID:24084325
Hydroxyurea is associated with lower prevalence of albuminuria in adults with sickle cell disease.
Laurin, Louis-Philippe; Nachman, Patrick H; Desai, Payal C; Ataga, Kenneth I; Derebail, Vimal K
2014-06-01
Albuminuria is an early manifestation of sickle cell nephropathy. Prior small case series suggests benefit of hydroxyurea in reducing albuminuria, with a similar trend noted in pediatric studies. We aimed to comprehensively evaluate hydroxyurea use and prevalence of albuminuria in adult sickle cell patients. We performed a cross-sectional study of 149 adult patients followed between 2000 and 2011 in a comprehensive sickle cell clinic. All patients were assessed for albuminuria either by direct measurement or by urinary chemical strip (dipstick) testing. Urinary albumin-to-creatinine ratios (UACRs) were available for 112 patients. Hydroxyurea exposure was defined as ≥3 months of therapy before the assessment of albuminuria. Albuminuria was defined as either UACR ≥30 mg/g or ≥1+ proteinuria on two separate dipsticks. We constructed a multivariate logistic regression model to assess the association between hydroxyurea and albuminuria. The prevalence of albuminuria was lower among patients on hydroxyurea (34.7 versus 55.4%; P = 0.01) as was median albumin excretion (17.9 versus 40.5 mg/g; P = 0.04). In multivariate analysis, hydroxyurea was associated with a lower likelihood of albuminuria (odds ratio 0.28, 95% CI: 0.11-0.75, P = 0.01), adjusting for age, angiotensin-converting enzyme inhibitor/angiotensin receptor blocker use, tricuspid regurgitant jet velocity, hypertension and acute chest syndrome. In our population of sickle cell patients, those using hydroxyurea were less than one-third as likely to exhibit albuminuria. Hydroxyurea use may prevent development of overt nephropathy or the progression of sickle cell disease nephropathy to end-stage renal disease, and its use for this indication merits further investigation. © The Author 2013. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.
How I use hydroxyurea to treat young patients with sickle cell anemia
2010-01-01
Hydroxyurea has many characteristics of an ideal drug for sickle cell anemia (SCA) and provides therapeutic benefit through multiple mechanisms of action. Over the past 25 years, substantial experience has accumulated regarding its safety and efficacy for patients with SCA. Early proof-of-principle studies were followed by prospective phase 1/2 trials demonstrating efficacy in affected adults, then adolescents and children, and more recently infants and toddlers. The phase 3 National Heart, Lung and Blood Institute–sponsored Multicenter Study of Hydroxyurea trial proved clinical efficacy for preventing acute vaso-occlusive events in severely affected adults. Based on this cumulative experience, hydroxyurea has emerged as an important therapeutic option for children and adolescents with recurrent vaso-occlusive events; recent evidence documents sustained long-term benefits with prevention or reversal of chronic organ damage. Despite abundant evidence for its efficacy, however, hydroxyurea has not yet translated into effective therapy for SCA. Because many healthcare providers have inadequate knowledge about hydroxyurea, patients and families are not offered treatment or decline because of unrealistic fears. Limited support for hydroxyurea by lay organizations and inconsistent medical delivery systems also contribute to underuse. Although questions remain regarding its long-term risks and benefits, current evidence suggests that many young patients with SCA should receive hydroxyurea treatment. PMID:20223921
Sheehan, Vivien A.; Crosby, Jacy R.; Sabo, Aniko; Mortier, Nicole A.; Howard, Thad A.; Muzny, Donna M.; Dugan-Perez, Shannon; Aygun, Banu; Nottage, Kerri A.; Boerwinkle, Eric; Gibbs, Richard A.; Ware, Russell E.; Flanagan, Jonathan M.
2014-01-01
Hydroxyurea has proven efficacy in children and adults with sickle cell anemia (SCA), but with considerable inter-individual variability in the amount of fetal hemoglobin (HbF) produced. Sibling and twin studies indicate that some of that drug response variation is heritable. To test the hypothesis that genetic modifiers influence pharmacological induction of HbF, we investigated phenotype-genotype associations using whole exome sequencing of children with SCA treated prospectively with hydroxyurea to maximum tolerated dose (MTD). We analyzed 171 unrelated patients enrolled in two prospective clinical trials, all treated with dose escalation to MTD. We examined two MTD drug response phenotypes: HbF (final %HbF minus baseline %HbF), and final %HbF. Analyzing individual genetic variants, we identified multiple low frequency and common variants associated with HbF induction by hydroxyurea. A validation cohort of 130 pediatric sickle cell patients treated to MTD with hydroxyurea was genotyped for 13 non-synonymous variants with the strongest association with HbF response to hydroxyurea in the discovery cohort. A coding variant in Spalt-like transcription factor, or SALL2, was associated with higher final HbF in this second independent replication sample and SALL2 represents an outstanding novel candidate gene for further investigation. These findings may help focus future functional studies and provide new insights into the pharmacological HbF upregulation by hydroxyurea in patients with SCA. PMID:25360671
Improved hydroxyurea effect with the use of text messaging in children with sickle cell anemia.
Estepp, Jeremie H; Winter, Bryan; Johnson, Margery; Smeltzer, Matthew P; Howard, Scott C; Hankins, Jane S
2014-11-01
In children with sickle cell anemia (SCA), hydroxyurea reduces morbidity, but adherence is frequently suboptimal. Because most families of children with SCA have access to cellular telephone services, we assessed the impact of text messaged reminders as a tool to improve adherence to hydroxyurea. All patients <19 years of age with HbSS or HbSβ(0) thalassemia who were treated with hydroxyurea at a maximal tolerated dosage (MTD) at St. Jude Children's Research Hospital Comprehensive Pediatric Sickle Cell Program and who received automated text message reminders (SIMON®) were retrospectively identified. Laboratory parameters, hospitalizations, and medication possession ratios (MPR) prior to and after initiation of SIMON® were compared to assess the impact of SIMON®. Of the 97.3% of families with access to a cell phone, 91% elected to receive text message reminders. Among 55 children receiving hydroxyurea at MTD, laboratory parameters reflected waning medication compliance during the 12 months prior to SIMON®. Following initiation of SIMON®, children had higher mean corpuscular volumes, hemoglobin levels and fetal hemoglobin percentages and lower absolute reticulocyte counts and bilirubin levels, suggesting improved medication adherence. Hospitalizations were uncommon before and after SIMON®, and medication possession ratios (MPRs) were high before and after SIMON®, neither was significantly changed. SIMON® was feasible and improved hematologic parameters in children with SCA receiving hydroxyurea at a MTD. Future work will include extension of this technology to children with other chronic medical conditions who require daily use of medication. © 2014 Wiley Periodicals, Inc.
1996-07-01
phase II study 1987-1989 Principal Investigator, Loyola/Hines pilot study of cisplatin preceded by concurrent cytarabine and oral hydroxyurea in...Investigator, Loyola/Hines pilot study of cisplatin preceded by concurrent 31 5 intravenous hydroxyurea and cytarabine . 1989-1992 Primary Study Coordinator...Conference: Modulation of cisplatin resistance by cytarabine and hydroxyurea. Illinois Cancer Council Annual Symposium: Review of Breast Cancer Growth
Rigano, Paolo; De Franceschi, Lucia; Sainati, Laura; Piga, Antonio; Piel, Frédéric B; Cappellini, Maria Domenica; Fidone, Carmelo; Masera, Nicoletta; Palazzi, Giovanni; Gianesin, Barbara; Forni, Gian Luca
2018-03-01
We conducted the first nation-wide cohort study of sickle cell disease (SCD) in Italy, a Southern European country exposed to intense recent flux migration from endemic areas for SCD. We evaluate the impact of hydroxyurea on a total of 652 pediatric and adult patients from 33 Reference Centers for SCD (mean age 24.5±15years, 51.4% males). Hydroxyurea median treatment duration was 7years (range: <1year to 29years) at a mean therapeutic dose of 18±4.7mg/kg/day. Hydroxyurea was associated with a significant increase in mean total and fetal hemoglobin and a significant decrease in mean hemoglobin S, white blood and platelet counts, and lactate dehydrogenase levels. Hydroxyurea was associated with a significant reduction in the incidence of acute chest syndrome (-29.3%, p<0.001), vaso-occlusive crisis (-34.1%, p<0.001), hospitalization (-53.2%, p<0.001), and bone necrosis (-6.9%, p<0.001). New silent cerebral infarction (SCI) occurred during treatment (+42.4%, p<0.001) but not stroke (+0.5%, p=0.572). These observations were generally consistent upon stratification for age, descent (Caucasian or African), genotype (βS/βS, βS/β 0 or βS/β + ) and duration of treatment (< or ≥10years). There were no new safety concerns observed compared to those commonly reported in the literature. Our study, conducted on a large population of patients with different descent and compound state supports the benefits of hydroxyurea therapy as a treatment option. Registered at clinical trials.gov (NCT02709681). Copyright © 2017 Elsevier Inc. All rights reserved.
Molecular Analysis of the Inheritance of Transcriptional Silencing
2007-04-01
arrest, to synchronize the cells for hydroxyurea (HU) addition, and then released into an alpha factor/0.2M HU arrest (Fig. 1A). 2 hours after release...restrictive conditions to degrade both Sir1td and Asf1td proteins. Cells were then release for 4 hours into 0.2M hydroxyurea (HU), an early S phase arrest...on three experiments. The “Block” row describes the cell cycle inhibitor used in each time point (alpha factor, hydroxyurea and nocodozole). 24
Hankins, Jane S.; Aygun, Banu; Nottage, Kerri; Thornburg, Courtney; Smeltzer, Matthew P.; Ware, Russell E.; Wang, Winfred C.
2014-01-01
Abstract Despite documented laboratory and clinical benefits of hydroxyurea for children with sickle cell anemia (SCA), the drug's long-term safety and efficacy remains poorly defined. The HUSOFT trial and extension study examined feasibility, toxicity, and hematological efficacy of hydroxyurea in infants with SCA. This report describes HUSOFT participants who have continued hydroxyurea therapy for 15 years. With IRB approval, medical records were reviewed for clinical, laboratory, and growth parameters. Twenty-eight infants enrolled in the original 2-year HUSOFT study received open-label liquid hydroxyurea at 20 mg/kg/day; 17 completed the extension study with dose escalation to 30 mg/kg/day. Eight of these 17 (6 girls and 2 boys, all HbSS) have continued on daily hydroxyurea for at least 15 years (median age at last follow-up 17.6 years) without interruption. All hematologic indices (Hb concentration, mean corpuscular volume (MCV), fetal hemoglobin) showed sustained effect after 15 years. The median maximum tolerated dose of hydroxyurea has decreased from 30 to 26 mg/kg/day (range 19.5–31.2); neutropenia [absolute neutrophil count (ANC) < 1.0 × 109/L] prompting temporary drug discontinuation occurred a total of 10 times in 4 subjects and there was no severe neutropenia (ANC < 0.5 × 109/L). Growth rates over 15 years continued at the 50th percentile for both height and weight, and puberty occurred without delay (age range 10–14 years). There were 5.1 vaso-occlusive events (pain and acute chest syndrome)/100 patient years, 7.3 packed red blood cell transfusions/100 patient years. No malignancies, strokes, or deaths occurred. At last follow up, all subjects were at appropriate grade level (10–12 grade) with no history of repeated grades. A cohort of young teenagers with SCA who initiated treatment in infancy have had sustained and continued hematological benefits for a decade and a half. Growth and sexual development are normal and comparable to the general pediatric population. Continuous hydroxyurea therapy since infancy appears safe and efficacious in SCA. PMID:25526439
Hankins, Jane S; Aygun, Banu; Nottage, Kerri; Thornburg, Courtney; Smeltzer, Matthew P; Ware, Russell E; Wang, Winfred C
2014-12-01
Despite documented laboratory and clinical benefits of hydroxyurea for children with sickle cell anemia (SCA), the drug's long-term safety and efficacy remains poorly defined. The HUSOFT trial and extension study examined feasibility, toxicity, and hematological efficacy of hydroxyurea in infants with SCA. This report describes HUSOFT participants who have continued hydroxyurea therapy for 15 years. With IRB approval, medical records were reviewed for clinical, laboratory, and growth parameters. Twenty-eight infants enrolled in the original 2-year HUSOFT study received open-label liquid hydroxyurea at 20 mg/kg/day; 17 completed the extension study with dose escalation to 30 mg/kg/day. Eight of these 17 (6 girls and 2 boys, all HbSS) have continued on daily hydroxyurea for at least 15 years (median age at last follow-up 17.6 years) without interruption. All hematologic indices (Hb concentration, mean corpuscular volume (MCV), fetal hemoglobin) showed sustained effect after 15 years. The median maximum tolerated dose of hydroxyurea has decreased from 30 to 26 mg/kg/day (range 19.5-31.2); neutropenia [absolute neutrophil count (ANC)<1.0×10⁹/L] prompting temporary drug discontinuation occurred a total of 10 times in 4 subjects and there was no severe neutropenia (ANC<0.5×10⁹/L). Growth rates over 15 years continued at the 50th percentile for both height and weight, and puberty occurred without delay (age range 10-14 years). There were 5.1 vaso-occlusive events (pain and acute chest syndrome)/100 patient years, 7.3 packed red blood cell transfusions/100 patient years. No malignancies, strokes, or deaths occurred. At last follow up, all subjects were at appropriate grade level (10-12 grade) with no history of repeated grades. A cohort of young teenagers with SCA who initiated treatment in infancy have had sustained and continued hematological benefits for a decade and a half. Growth and sexual development are normal and comparable to the general pediatric population. Continuous hydroxyurea therapy since infancy appears safe and efficacious in SCA.
Hydroxyurea therapy contributes to infertility in adult men with sickle cell disease: a review.
DeBaun, Michael R
2014-12-01
Hydroxyurea therapy, a chemotherapeutic agent, is the only US FDA approved therapy for the prevention of vaso-occlusive pain in sickle cell disease (SCD). The National Institutes of Health has sponsored two Phase III randomized, placebo-controlled trials, initially in adults, and subsequently in children with sickle cell anemia (SCA). Despite the overwhelming evidence that hydroxyurea therapy is beneficial to children and adults with SCA, individuals with SCA and their families express reservations about its use, in part because of the concerns about fertility, particularly in men. As adolescent boys with SCD are now expected to reach their reproductive years, a new concern is emerging about the role of hydroxyurea therapy as a barrier to their progeny. This review will systemically evaluate compromised fertility in men with SCD, and the evidence that hydroxyurea therapy is associated with further decreasing fertility in men with SCD.
Hankins, Jane S.; McCarville, M. Beth; Rankine-Mullings, Angela; Reid, Marvin E.; Lobo, Clarisse L.C.; Moura, Patricia G.; Ali, Susanna; Soares, Deanne; Aldred, Karen; Jay, Dennis W.; Aygun, Banu; Bennett, John; Kang, Guolian; Goldsmith, Jonathan C.; Smeltzer, Matthew P.; Boyett, James M.; Ware, Russell E.
2015-01-01
Children with sickle cell anemia (SCA) and conditional transcranial Doppler (TCD) ultrasound velocities (170-199 cm/sec) may develop stroke. However, with limited available clinical data, the current standard of care for conditional TCD velocities is observation. The efficacy of hydroxyurea in preventing conversion from conditional to abnormal TCD (≥200 cm/sec), which confers a higher stroke risk, has not been studied prospectively in a randomized trial. Sparing Conversion to Abnormal TCD Elevation (SCATE #NCT01531387) was an NHLBI-funded Phase III multicenter international clinical trial comparing alternative therapy (hydroxyurea) to standard care (observation) to prevent conversion from conditional to abnormal TCD velocity in children with SCA. SCATE enrolled 38 children from the United States, Jamaica, and Brazil [HbSS (36), HbSβ0-thalassemia (1), and HbSD (1), median age 5.4 years (range, 2.7-9.8)]. Due to slow patient accrual and administrative delays, SCATE was terminated early. In an intention-to-treat analysis, the cumulative incidence of abnormal conversion was 9% (95% CI 0 to 35%) in the hydroxyurea arm and 47% (95% CI 6 to 81%) in observation arm at 15 months (p=0.16). In post-hoc analysis according to treatment received, significantly fewer children on hydroxyurea converted to abnormal TCD velocities, compared to observation (0% versus 50%, p=0.02). After a mean of 10.1 months, a significant change in mean TCD velocity was observed with hydroxyurea treatment (−15.5 versus +10.2 cm/sec, p=0.02). No stroke events occurred in either arm. Hydroxyurea reduces TCD velocities in children with SCA and conditional velocities. PMID:26414435
Hankins, Jane S; McCarville, Mary Beth; Rankine-Mullings, Angela; Reid, Marvin E; Lobo, Clarisse L C; Moura, Patricia G; Ali, Susanna; Soares, Deanne P; Aldred, Karen; Jay, Dennis W; Aygun, Banu; Bennett, John; Kang, Guolian; Goldsmith, Jonathan C; Smeltzer, Matthew P; Boyett, James M; Ware, Russell E
2015-12-01
Children with sickle cell anemia (SCA) and conditional transcranial Doppler (TCD) ultrasound velocities (170-199 cm/sec) may develop stroke. However, with limited available clinical data, the current standard of care for conditional TCD velocities is observation. The efficacy of hydroxyurea in preventing conversion from conditional to abnormal TCD (≥200 cm/sec), which confers a higher stroke risk, has not been studied prospectively in a randomized trial. Sparing Conversion to Abnormal TCD Elevation (SCATE #NCT01531387) was a National Heart, Lung, and Blood Institute-funded Phase III multicenter international clinical trial comparing alternative therapy (hydroxyurea) to standard care (observation) to prevent conversion from conditional to abnormal TCD velocity in children with SCA. SCATE enrolled 38 children from the United States, Jamaica, and Brazil [HbSS (36), HbSβ(0) -thalassemia (1), and HbSD (1), median age = 5.4 years (range, 2.7-9.8)]. Because of the slow patient accrual and administrative delays, SCATE was terminated early. In an intention-to-treat analysis, the cumulative incidence of abnormal conversion was 9% (95% CI = 0-35%) in the hydroxyurea arm and 47% (95% CI = 6-81%) in observation arm at 15 months (P = 0.16). In post hoc analysis according to treatment received, significantly fewer children on hydroxyurea converted to abnormal TCD velocities when compared with observation (0% vs. 50%, P = 0.02). After a mean of 10.1 months, a significant change in mean TCD velocity was observed with hydroxyurea treatment (-15.5 vs. +10.2 cm/sec, P = 0.02). No stroke events occurred in either arm. Hydroxyurea reduces TCD velocities in children with SCA and conditional velocities. © 2015 Wiley Periodicals, Inc.
Colombatti, Raffaella; Palazzi, Giovanni; Masera, Nicoletta; Notarangelo, Lucia Dora; Bonetti, Elisa; Samperi, Piera; Barone, Angelica; Perrotta, Silverio; Facchini, Elena; Miano, Maurizio; Del Vecchio, Giovanni Carlo; Guerzoni, Maria Elena; Corti, Paola; Menzato, Federica; Cesaro, Simone; Casale, Maddalena; Rigano, Paolo; Forni, Gian Luca; Russo, Giovanna; Sainati, Laura
2018-02-01
The number of patients with sickle cell disease (SCD) has increased in Italy in the past decade due to immigration. In spite of the established efficacy of hydroxyurea (HU) in childhood, population-based data regarding its prescription and effectiveness come mainly from studies performed in adults or outside Europe. The Hydroxyurea in SCD: A Large Nation-wide Cohort Study from Italy was a retrospective cohort study of adult and pediatric patients with SCD attending 32 centers. Pediatric data are analyzed separately. Out of 504 children followed in 11 centers, 206 (40%) were on HU (194 SS/Sβ°, 12 SC/Sß+); 74% came from Sub-Saharian Africa and 18% from Europe. HU therapy indications for SS/Sβ° patients were as follows: 57% painful vaso-occlusive crisis, acute chest syndrome or both, 24% anemia, 8% anemia, and other reasons (the majority had Hb ≤ 8-8.5 g/dl, revealing scarce acceptance of low Hb values by pediatric hematologist). Mean starting dose was 15.5 mg/kg, and dose at full regimen was 17.1 mg/kg. Mean age at HU therapy was 7.68 years, although it was lower for SS/Sβ° patients. Only 10% started HU before 3 years. In 92%, 500 mg capsule was used; in 6%, the galenic was used; and in 2%, 100 mg tablet was used. Significant reduction of clinical events and inpatients admissions, with improvement in hematological parameters, was observed for SS/Sβ° patients and a trend toward improvement for SC/Sß+ patients was also observed. HU effectiveness is demonstrated in a national cohort of children with SCD living in Italy, even at a lower dose than recommended, revealing good adherence to a treatment program by a socially vulnerable group of patients such as immigrants. © 2017 Wiley Periodicals, Inc.
Population pharmacokinetics of hydroxyurea for children and adolescents with sickle cell disease.
Wiczling, Paweł; Liem, Robert I; Panepinto, Julie A; Garg, Uttam; Abdel-Rahman, Susan M; Kearns, Gregory L; Neville, Kathleen A
2014-09-01
The objective of this study was to develop a population pharmacokinetic (PK) model sufficient to describe hydroxyurea (HU) concentrations in serum and urine following oral drug administration in pediatric patients with sickle cell disease. Additionally, the measured hydroxyurea concentrations for particular sampling time were correlated with exposure measures (AUC) to find the most predictive relationship. Hydroxyurea concentrations were determined in 21 subjects. Using a population nonlinear mixed-effect modeling, the HU PK was best described by a one-compartment model with two elimination pathways (metabolic and renal) and a transit compartment absorption. The typical mean absorption time was 0.222 hour. The typical apparent volume of distribution was 21.8 L and the apparent systemic clearance was 6.88 L/h for an average weight patient of 30.7 kg. The 50% of the HU dose was renally excreted. Linear correlations were apparent between the plasma HU concentration at 1, 1.5, 2, 4, and 6 hours post-dose and AUC with the most significant (R(2) = 0.71) observed at 1.5 hours. A population PK model was successful in describing HU disposition in plasma and urine. Data from the model also demonstrated that HU plasma concentrations at 1.5 hours after an oral dose of the drug were highly predictive of systemic drug exposure. © 2014, The American College of Clinical Pharmacology.
Hydroxyurea therapy in UK children with sickle cell anaemia: A single-centre experience.
Phillips, Kate; Healy, Laura; Smith, Louise; Keenan, Russell
2018-02-01
Despite the demonstrated efficacy of hydroxyurea therapy, children with sickle cell anaemia in the UK are preferentially managed with supportive care or transfusion. Hydroxyurea is reserved for children with severe disease phenotype. This is in contrast to North America and other countries where hydroxyurea is widely used for children of all clinical phenotypes. The conservative UK practice may in part be due to concerns about toxicity, in particular marrow suppression with high doses, and growth in children. We monitored 37 paediatric patients with sickle cell anaemia who were treated with hydroxyurea at a single UK treatment centre. Therapy was well tolerated and mild transient cytopenias were the only toxicity observed. Comparative analysis of patients receiving ≥26 mg/kg/day versus <26 mg/kg/day demonstrates increasing dose has a significant positive effect on foetal haemoglobin (Hb; 29.2% vs. 20.4%, P = 0.0151), mean cell volume (94.4 vs. 86.5, P = 0.0183) and reticulocyte count (99.66 × 10 9 /l vs. 164.3 × 10 9 /l, P = 0.0059). Marrow suppression was not a clinical problem with high-dose treatment, Hb 92.25 g/l versus 91.81 g/l (ns), neutrophil count 3.3 × 10 9 /l versus 4.8 × 10 9 /l (ns) and platelet count 232.4 × 10 9 /l versus 302.2 × 10 9 /l (ns). Normal growth rates were maintained in all children. Good adherence to therapy was a significant factor in reducing hospitalisations. This study demonstrates the effectiveness and safety in practice of high-dose hydroxyurea as a disease-modifying therapy, which we advocate for all children with sickle cell anaemia. © 2017 The Authors. Pediatric Blood & Cancer Published by Wiley Periodicals, Inc.
Reardon, David A; Egorin, Merrill J; Quinn, Jennifer A; Rich, Jeremy N; Rich, Jeremy N; Gururangan, Sridharan; Gururangan, Idharan; Vredenburgh, James J; Desjardins, Annick; Sathornsumetee, Sith; Provenzale, James M; Herndon, James E; Dowell, Jeannette M; Badruddoja, Michael A; McLendon, Roger E; Lagattuta, Theodore F; Kicielinski, Kimberly P; Dresemann, Gregor; Sampson, John H; Friedman, Allan H; Salvado, August J; Friedman, Henry S
2005-12-20
We performed a phase II study to evaluate the combination of imatinib mesylate, an adenosine triphosphate mimetic, tyrosine kinase inhibitor, plus hydroxyurea, a ribonucleotide reductase inhibitor, in patients with recurrent glioblastoma multiforme (GBM). Patients with GBM at any recurrence received imatinib mesylate plus hydroxyurea (500 mg twice a day) orally on a continuous, daily schedule. The imatinib mesylate dose was 500 mg twice a day for patients on enzyme-inducing antiepileptic drugs (EIAEDs) and 400 mg once a day for those not on EIAEDs. Assessments were performed every 28 days. The primary end point was 6-month progression-free survival (PFS). Thirty-three patients enrolled with progressive disease after prior radiotherapy and at least temozolomide-based chemotherapy. With a median follow-up of 58 weeks, 27% of patients were progression-free at 6 months, and the median PFS was 14.4 weeks. Three patients (9%) achieved radiographic response, and 14 (42%) achieved stable disease. Cox regression analysis identified concurrent EIAED use and no more than one prior progression as independent positive prognostic factors of PFS. The most common toxicities included grade 3 neutropenia (16%), thrombocytopenia (6%), and edema (6%). There were no grade 4 or 5 events. Concurrent EIAED use lowered imatinib mesylate exposure. Imatinib mesylate clearance was decreased at day 28 compared with day 1 in all patients, suggesting an effect of hydroxyurea. Imatinib mesylate plus hydroxyurea is well tolerated and associated with durable antitumor activity in some patients with recurrent GBM.
Interaction of N-hydroxyurea with strong proton donors: HCl and HF
NASA Astrophysics Data System (ADS)
Sałdyka, Magdalena
2014-11-01
An infrared spectroscopic and MP2/6-311++G(2d,2p) study of strong hydrogen bonded complexes of N-hydroxyurea (NH2CONHOH) with hydrogen halides (HCl and HF) trapped in solid argon matrices is reported. 1:1 and 1:2 complexes between N-hydroxyurea and hydrogen chloride, hydrogen fluoride have been identified in the NH2CONHOH/HCl/Ar, NH2CONHOH/HF/Ar matrices, respectively; their structures were determined by comparison of the spectra with the results of calculations. In the 1:1 complexes, identified for both hydrogen halide molecules, the cyclic structure stabilized by the X-H⋯O and N-H⋯X bonds is present; for the NH2CONHOH⋯HF system another isomeric 1:1 complex is also observed. Two 1:2 complexes were identified for the N-hydroxyurea-hydrogen chloride system characterised by the Cl-H⋯O and N-H⋯Cl bonds. The results of the study evidence that N-hydroxyurea is an oxygen base in the gas-phase with the carbonyl group as the strongest proton acceptor centre in the molecule.
Phase II study of Gleevec® plus hydroxyurea (HU) in adults with progressive or recurrent meningioma.
Reardon, David A; Norden, Andrew D; Desjardins, Annick; Vredenburgh, James J; Herndon, James E; Coan, April; Sampson, John H; Gururangan, Sridharan; Peters, Katherine B; McLendon, Roger E; Norfleet, Julie A; Lipp, Eric S; Drappatz, Jan; Wen, Patrick Y; Friedman, Henry S
2012-01-01
We prospectively evaluated the efficacy and safety of imatinib plus hydroxyurea in patients with progressive/recurrent meningioma. A total of 21 patients with progressive/recurrent meningioma were enrolled in this dual center, single-arm, phase II trial. All patients received 500 mg of hydroxyurea twice a day. Imatinib was administered at 400 mg/day for patients not on CYP3A enzyme inducing anti-epileptic drugs (EIAEDs) and at 500 mg twice a day for patients on EIAEDs. The primary endpoint was progression-free survival at 6 months (PFS-6) and secondary endpoints were safety, radiographic response rate, and overall survival (OS). Best radiographic response was stable disease and was observed in 14 patients (67%). PFS-6 for all patients, those with grade I tumors (n = 8) and those with grade II or III tumors (n = 13) was 61.9, 87.5 and 46.2%, respectively. Patients with grade II or III tumors had poorer PFS and OS than those with grade I tumors, (P = 0.025 and P = 0.018) respectively. The only grade 3 or greater adverse event occurring in ≥ 10% of patients was anemia (10%). Imatinib plus hydroxyurea is well tolerated among patients with meningioma but has modest anti-tumor activity for this indication.
Phase II study of Gleevec® plus hydroxyurea (HU) in adults with progressive or recurrent meningioma
Norden, Andrew D.; Desjardins, Annick; Vredenburgh, James J.; Herndon, James E.; Coan, April; Sampson, John H.; Gururangan, Sridharan; Peters, Katherine B.; McLendon, Roger E.; Norfleet, Julie A.; Lipp, Eric S.; Drappatz, Jan; Wen, Patrick Y.; Friedman, Henry S.
2011-01-01
We prospectively evaluated the efficacy and safety of imatinib plus hydroxyurea in patients with progressive/recurrent meningioma. A total of 21 patients with progressive/recurrent meningioma were enrolled in this dual center, single-arm, phase II trial. All patients received 500 mg of hydroxyurea twice a day. Imatinib was administered at 400 mg/day for patients not on CYP3A enzyme inducing anti-epileptic drugs (EIAEDs) and at 500 mg twice a day for patients on EIAEDs. The primary endpoint was progression-free survival at 6 months (PFS-6) and secondary endpoints were safety, radiographic response rate, and overall survival (OS). Best radiographic response was stable disease and was observed in 14 patients (67%). PFS-6 for all patients, those with grade I tumors (n = 8) and those with grade II or III tumors (n = 13) was 61.9, 87.5 and 46.2%, respectively. Patients with grade II or III tumors had poorer PFS and OS than those with grade I tumors, (P = 0.025 and P = 0.018) respectively. The only grade 3 or greater adverse event occurring in ≥10% of patients was anemia (10%). Imatinib plus hydroxyurea is well tolerated among patients with meningioma but has modest anti-tumor activity for this indication. PMID:21938530
Reardon, D A; Dresemann, G; Taillibert, S; Campone, M; van den Bent, M; Clement, P; Blomquist, E; Gordower, L; Schultz, H; Raizer, J; Hau, P; Easaw, J; Gil, M; Tonn, J; Gijtenbeek, A; Schlegel, U; Bergstrom, P; Green, S; Weir, A; Nikolova, Z
2009-12-15
We evaluated the efficacy of imatinib mesylate in addition to hydroxyurea in patients with recurrent glioblastoma (GBM) who were either on or not on enzyme-inducing anti-epileptic drugs (EIAEDs). A total of 231 patients with GBM at first recurrence from 21 institutions in 10 countries were enrolled. All patients received 500 mg of hydroxyurea twice a day. Imatinib was administered at 600 mg per day for patients not on EIAEDs and at 500 mg twice a day if on EIAEDs. The primary end point was radiographic response rate and secondary end points were safety, progression-free survival at 6 months (PFS-6), and overall survival (OS). The radiographic response rate after centralised review was 3.4%. Progression-free survival at 6 months and median OS were 10.6% and 26.0 weeks, respectively. Outcome did not appear to differ based on EIAED status. The most common grade 3 or greater adverse events were fatigue (7%), neutropaenia (7%), and thrombocytopaenia (7%). Imatinib in addition to hydroxyurea was well tolerated among patients with recurrent GBM but did not show clinically meaningful anti-tumour activity.
Inoue, Susumu; Khan, Isra'a; Mushtaq, Rao; Sanikommu, Srinivasa Reddy; Mbeumo, Carline; LaChance, Jenny; Roebuck, Michael
2016-01-01
Pain management at the emergency department (ED) for vaso-occulsive crisis (VOC) for patients with sickle cell disease has not been optimum, with a long delay in giving the initial analgesic. We conducted a retrospective survey over a 7-year period to determine our ED's timing in giving pain medication to patients with VOC as a quality improvement project. We compared different periods, children vs adults, and the influence of gender in the analgesic administration timing. This is a retrospective chart review of three different periods: (1) years 2007-2008, (2) years 2011-2012, and (3) year 2013. We extracted relevant information from ED records. Data were analyzed using Student t test, chi-square analysis, and the Kruskal-Wallis test. There was a progressive improvement in the time interval to the 1st analgesic over these three periods. Children received analgesics more quickly than adults in all periods. Male adult patients received pain medication faster than female adult patients, although initial pain scores were higher in female than in male patients. Progressively fewer pediatric patients utilized ED over these three periods, but no difference for adult patients was observed. The proportion of pediatric patients admitted to the hospital increased with each period. The progressive decrease in both the number of patients and the number of visits to the ED by children suggested that the collective number of VOC in children has decreased, possibly secondary to the dissemination of hydroxyurea use. We failed to observe the same trend in adult patients. The need for IV access, and ordering laboratory tests or imaging studies tends to delay analgesic administration. Delay in administration of the first analgesic was more pronounced for female adult patients than male adult patients in spite of their higher pain score. Health care providers working in ED should make conscious efforts to respect pain in women as well as pain in men. Though not proven from this study, we believe that a significantly wider use of hydroxyurea by adult patients most likely would reduce their utilization of ED for the purpose of relief of pain, and further pediatric hematologists may be better positioned to increase hydroxyurea adherence by young adult patients, since they have had established rapport with them before transitioning to adult care.
Reardon, David A.; Egorin, Merrill J.; Desjardins, Annick; Vredenburgh, James J.; Beumer, Jan H.; Lagattuta, Theodore F.; Gururangan, Sridharan; Herndon, James E.; Salvado, August J.; Friedman, Henry S.
2009-01-01
Background We determined the maximum tolerated dose (MTD) and dose-limiting toxicities (DLT) of the oral vascular endothelial growth factor receptor (VEGFR) inhibitor, vatalanib, when administered with imatinib and hydroxyurea on a continuous daily schedule among recurrent malignant glioma patients. Methods All patients received 500 mg of hydroxyurea twice daily. Imatinib was dosed at 400 mg per day for patients not taking enzyme-inducing antiepileptic drugs (EIAEDs; stratum A) and at 500 mg twice-a-day for patients taking EIAEDs (stratum B). Vatalanib was escalated from 500 mg to 1250 mg twice daily in successive cohorts, independently for each stratum. Pharmacokinetics of each drug were assessed. Results Thirty-seven recurrent patients, including 34 (92%) with glioblastoma and 3 (8%) with grade 3 malignant glioma, were enrolled. Nineteen patients (51%) were taking EIAEDs. The MTD of vatalanib for all patients was 1000 mg twice-a-day. DLTs were hematologic, gastrointestinal, renal and hepatic. No patients developed intracranial hemorrhage. Concurrent administration of imatinib and hydroxyurea did not affect vatalanib exposure, but EIAEDs decreased vatalanib and imatinib plasma exposures. Conclusion Vatalanib doses up to 1000 mg twice-a-day combined with imatinib and hydroxyurea are well tolerated. Strategies to target tumor blood vessel endothelial cells and pericytes by inhibiting VEGFR and PDGFR, respectively, are safe among recurrent malignant glioma patients and may enhance anti-angiogenesis activity. PMID:19248046
Edesa, Wael Abdelgawad; Abdel-malek, Raafat Ragaey
2015-06-01
Optimal response requires that patients should be maintained on the drug continuously. To evaluate the influence of imatinib interruption and prior hydroxyurea use on the outcome of patients with chronic myeloid leukemia. Between January 2010 and November 2013, patients with chronic phase who received imatinib at the Kasr Al-ainy Center of Clinical Oncology were included. Sixty patients were included in this study, thirty three patients (55%) received imatinib upfront, while 27 (45%) received imatinib post hydroxyurea. Imatinib was not given regularly in 50% of patients. In terms of response, only major molecular response and complete molecular response were statistically significant in favor of patients who were receiving imatinib regularly compared to those who had interruption (p<0.001, p<0.001, respectively) , while there was no difference in patients stratified according to prior hydroxyurea. The median progression free survival was 30.3 months (95% CI 24.3-36.3). Among the group of patients who received imatinib regularly, progression free survival was longer (p=0.049), there was no difference between those who received prior hydroxyurea versus those who did not (p=0.67). Duration of prior hydroxyurea had no impact on response or progression free survival, while patients regular on imatinib had statistically significant difference with respect to major molecular response, complete molecular response and progression free survival compared to those who had periods of drug interruption, thus we need more governmental support to supply the drug without interruption to improve the outcome of therapy. Copyright © 2015 The Authors. Production and hosting by Elsevier B.V. All rights reserved.
Reardon, David A.; Desjardins, Annick; Vredenburgh, James J.; Herndon, James E.; Coan, April; Gururangan, Sridharan; Peters, Katherine B.; McLendon, Roger; Sathornsumetee, Sith; Rich, Jeremy N.; Lipp, Eric S.; Janney, Dorothea; Friedman, Henry S.
2013-01-01
Background We evaluated the efficacy of imatinib plus hydroxyurea in patients with progressive/recurrent low-grade glioma. Methods A total of 64 patients with recurrent/progressive low-grade glioma were enrolled in this single-center study that stratified patients into astrocytoma and oligodendroglioma cohorts. All patients received 500 mg of hydroxyurea twice a day. Imatinib was administered at 400 mg per day for patients not on EIAEDs and at 500 mg twice a day if on EIAEDs. The primary endpoint was progression-free survival at 12 months (PFS-12) and secondary endpoints were safety, median progression-free survival and radiographic response rate. Results Thirty-two patients were enrolled into each cohort. Eleven patients (17%) had prior radiotherapy and 24 (38%) had received prior chemotherapy. The median PFS and PFS-12 were 11 months and 39%, respectively. Outcome did not differ between the histologic cohorts. No patient achieved a radiographic response. The most common grade 3 or greater adverse events were neutropenia (11%), thrombocytopenia (3%) and diarrhea (3%). Conclusions Imatinib plus hydroxyurea was well tolerated among recurrent/progressive LGG patients but this regimen demonstrated negligible anti-tumor activity. PMID:22371319
Reardon, D A; Dresemann, G; Taillibert, S; Campone, M; van den Bent, M; Clement, P; Blomquist, E; Gordower, L; Schultz, H; Raizer, J; Hau, P; Easaw, J; Gil, M; Tonn, J; Gijtenbeek, A; Schlegel, U; Bergstrom, P; Green, S; Weir, A; Nikolova, Z
2009-01-01
Background: We evaluated the efficacy of imatinib mesylate in addition to hydroxyurea in patients with recurrent glioblastoma (GBM) who were either on or not on enzyme-inducing anti-epileptic drugs (EIAEDs). Methods: A total of 231 patients with GBM at first recurrence from 21 institutions in 10 countries were enrolled. All patients received 500 mg of hydroxyurea twice a day. Imatinib was administered at 600 mg per day for patients not on EIAEDs and at 500 mg twice a day if on EIAEDs. The primary end point was radiographic response rate and secondary end points were safety, progression-free survival at 6 months (PFS-6), and overall survival (OS). Results: The radiographic response rate after centralised review was 3.4%. Progression-free survival at 6 months and median OS were 10.6% and 26.0 weeks, respectively. Outcome did not appear to differ based on EIAED status. The most common grade 3 or greater adverse events were fatigue (7%), neutropaenia (7%), and thrombocytopaenia (7%). Conclusions: Imatinib in addition to hydroxyurea was well tolerated among patients with recurrent GBM but did not show clinically meaningful anti-tumour activity. PMID:19904263
Phase II study of imatinib mesylate and hydroxyurea for recurrent grade III malignant gliomas.
Desjardins, Annick; Quinn, Jennifer A; Vredenburgh, James J; Sathornsumetee, Sith; Friedman, Allan H; Herndon, James E; McLendon, Roger E; Provenzale, James M; Rich, Jeremy N; Sampson, John H; Gururangan, Sridharan; Dowell, Jeannette M; Salvado, August; Friedman, Henry S; Reardon, David A
2007-05-01
Recent reports demonstrate the activity of imatinib mesylate, an ATP-mimetic, tyrosine kinase inhibitor, plus hydroxyurea, a ribonucleotide reductase inhibitor, in patients with recurrent glioblastoma multiforme. We performed the current phase 2 study to evaluate this regimen among patients with recurrent WHO grade III malignant glioma (MG). Patients with grade III MG at any recurrence, received imatinib mesylate plus hydroxyurea (500 mg twice a day) orally on a continuous, daily schedule. The imatinib mesylate dose was 500 mg twice a day for patients on enzyme inducing anti-epileptic drugs (EIAEDs) and 400 mg once a day for those not on EIAEDs. Clinical assessments were performed monthly and radiographic assessments were obtained at least every 2 months. The primary endpoint was 6-month progression-free survival (PFS) rate. Thirty-nine patients were enrolled. All patients had progressive disease after prior radiotherapy and at least temozolomide-based chemotherapy. The median number of episodes of prior progression was 2 (range, 1-7) and the median number of prior treatment regimens was 3 (range, 1-8). With a median follow-up of 82.9 weeks, 24% of patients were progression-free at 6 months. The radiographic response rate was 10%, while 33% achieved stable disease. Among patients who achieved at least stable disease at first evaluation, the 6-month and 12-month PFS rates were 53% and 29%, respectively. The most common grade 3 or greater toxicities were hematologic and complicated less than 4% of administered courses. Imatinib mesylate plus hydroxyurea, is well tolerated and associated with anti-tumor activity in some patients with recurrent grade 3 MG.
Replication in hydroxyurea: it's a matter of time.
Alvino, Gina M; Collingwood, David; Murphy, John M; Delrow, Jeffrey; Brewer, Bonita J; Raghuraman, M K
2007-09-01
Hydroxyurea (HU) is a DNA replication inhibitor that negatively affects both the elongation and initiation phases of replication and triggers the "intra-S phase checkpoint." Previous work with budding yeast has shown that, during a short exposure to HU, MEC1/RAD53 prevent initiation at some late S phase origins. In this study, we have performed microarray experiments to follow the fate of all origins over an extended exposure to HU. We show that the genome-wide progression of DNA synthesis, including origin activation, follows the same pattern in the presence of HU as in its absence, although the time frames are very different. We find no evidence for a specific effect that excludes initiation from late origins. Rather, HU causes S phase to proceed in slow motion; all temporal classes of origins are affected, but the order in which they become active is maintained. We propose a revised model for the checkpoint response to HU that accounts for the continued but slowed pace of the temporal program of origin activation.
A Cutaneous Lupus Erythematosus-Like Eruption Induced by Hydroxyurea.
Yanes, Daniel A; Mosser-Goldfarb, Joy L
2017-01-01
Hydroxyurea is a medication with many well-described cutaneous side effects, notably the dermatomyositis-like eruption known as hydroxyurea dermopathy. Although systemic lupus erythematosus has been reported with hydroxyurea use, cutaneous lupus has not. We report a novel case of chronic cutaneous lupus induced by hydroxyurea and propose that this is a side effect that is distinct from hydroxyurea dermopathy. © 2016 Wiley Periodicals, Inc.
[Curative Effects of Hydroxyurea on the Patients with β-thalassaemia Intermadia].
Huang, Li; Yao, Hong-Xia
2016-06-01
To investigate the clinical features of β-thalassaemia intermediate (TI) patients and the curative effect and side reactions of hydroxyurea therapys. Twenty nine patients with TI were divided into hydroxyurea therapy group and no hydroxyurea therapy group; the curative effect and side reactions in 2 groups were compared; the situation of blood transfusion in the 2 groups was evaluated. In hydroxyurea therapy group, the hemoglobin level increased after treatment for 3 months; the reticulocyte percentage obviously decreased after treatment for 12 months; the serum ferritin had been maintained at a low level; while in no hydroxyurea therapy group, the levels of hemoglobin and reticulocytes were not significantly improved after treatment, the serum ferritin level gradually increased. In hydroxyurea therapy group, 12 cases were out of blood transfusion after treatment for 12 months, effective rate of treatment was 85.71%; while in no hydroxyurea therapy group, the blood transfusion dependency was not improved after treatment. No serious side reactions were found in all the hydroxyurea treated patients. The hydroxyurea shows a better curative effect on TI patients, no serious side reactions occur in all the patients treated with hydroxyurea, but the long-term curative effect and side reactions should be observed continuously.
Hydroxyurea therapy for sickle cell anemia
McGann, Patrick T; Ware, Russell E
2017-01-01
Introduction Sickle cell anemia (SCA) is a severe, inherited hemoglobin disorder affecting 100,000 persons in the US and millions worldwide. Hydroxyurea, a once daily oral medication, has emerged as the primary disease-modifying therapy for SCA. The accumulated body of evidence over 30 years demonstrates that hydroxyurea is a safe and effective therapy for SCA, but hydroxyurea remains underutilized for a variety of reasons. Areas covered In this review, we summarize the available evidence regarding the pharmacology, clinical, and laboratory benefits, and safety of hydroxy-urea therapy for the treatment of SCA. The purpose of this review is to provide the reader a comprehensive understanding of hydroxyurea and to reinforce the fact that hydroxyurea is a safe and effective medication for the treatment of SCA. Expert opinion In our opinion, hydroxyurea therapy should be considered standard-of-care for SCA, representing an essential component of patient management. Early initiation and broader use of hydroxyurea will alter the natural history of SCA, so affected children can live longer and healthier lives. In addition, hydroxyurea use should be extended to low-resource settings such as sub-Saharan Africa, where the burden of SCA and the need for hydroxyurea is arguably the greatest. PMID:26366626
Hydroxyurea therapy for sickle cell anemia.
McGann, Patrick T; Ware, Russell E
2015-01-01
Sickle cell anemia (SCA) is a severe, inherited hemoglobin disorder affecting 100,000 persons in the US and millions worldwide. Hydroxyurea, a once daily oral medication, has emerged as the primary disease-modifying therapy for SCA. The accumulated body of evidence over 30 years demonstrates that hydroxyurea is a safe and effective therapy for SCA, but hydroxyurea remains underutilized for a variety of reasons. In this review, we summarize the available evidence regarding the pharmacology, clinical, and laboratory benefits, and safety of hydroxyurea therapy for the treatment of SCA. The purpose of this review is to provide the reader a comprehensive understanding of hydroxyurea and to reinforce the fact that hydroxyurea is a safe and effective medication for the treatment of SCA. In our opinion, hydroxyurea therapy should be considered standard-of-care for SCA, representing an essential component of patient management. Early initiation and broader use of hydroxyurea will alter the natural history of SCA, so affected children can live longer and healthier lives. In addition, hydroxyurea use should be extended to low-resource settings such as sub-Saharan Africa, where the burden of SCA and the need for hydroxyurea is arguably the greatest.
Griesshammer, Martin; Saydam, Guray; Palandri, Francesca; Benevolo, Giulia; Egyed, Miklos; Callum, Jeannie; Devos, Timothy; Sivgin, Serdar; Guglielmelli, Paola; Bensasson, Caroline; Khan, Mahmudul; Ronco, Julian Perez; Passamonti, Francesco
2018-05-27
RESPONSE-2 is a phase 3 study comparing the efficacy and safety of ruxolitinib with the best available therapy (BAT) in hydroxyurea-resistant/hydroxyurea-intolerant polycythemia vera (PV) patients without palpable splenomegaly. This analysis evaluated the durability of the efficacy and safety of ruxolitinib after patients completed the visit at week 80 or discontinued the study. Endpoints included proportion of patients achieving hematocrit control (< 45%), proportion of patients achieving complete hematologic remission (CHR) at week 28, and the durability of hematocrit control and CHR. At the time of analysis, 93% (69/74) of patients randomized to ruxolitinib were receiving ruxolitinib; while in the BAT arm, 77% (58/75) of patients crossed over to ruxolitinib after week 28. No patient remained on BAT by week 80. Among patients who achieved a hematocrit response at week 28, the probability of maintaining response up to week 80 was 78% in the ruxolitinib arm. At week 80, durable CHR was achieved in 18 patients (24%) in the ruxolitinib arm versus 2 patients (3%) in the BAT arm. The safety profile of ruxolitinib was consistent with previous reports. These data support that ruxolitinib treatment should be considered also as a standard of care for hydroxyurea-resistant/hydroxyurea-intolerant PV patients without palpable splenomegaly.
Dubowy, Ronald; Graham, Michael; Hakami, Nasrollah; Kletzel, Morris; Mahoney, Donald; Newman, Edward; Ravindranath, Yaddanapudi; Camitta, Bruce
2015-01-01
Summary At concentrations >0.1 mM, Hydroxyurea (HU) enhances the accumulation of cytosine arabinoside (ara-C) in leukemia cells in vitro. This study of children with refractory acute leukemia was designed to take advantage of this biochemical modulation. A fixed dose of HU and an escalating dose of ara-C were used. Oral HU, 1200 mg/m2 was followed 2 hours later by ara-C, 250-3100 mg/m2 intravenously in 15 minutes. The combination was given on days 1,2,3 and 8,9,10. Thirty-three children (26 ALL, 7 ANLL) were treated; 29 received at least one full course. All patients developed grade 4 cytopenias. Other grade 3-4 toxicities included: hyperbilirubinemia (2), elevated transaminases (3), transient gait disturbance (1), stomatitis (3), typhlitis (1), nausea/vomiting (9) and marrow aplasia >4 weeks (1). Three patients had intracranial bleeds while thrombocytopenic. Only liver toxicities and nausea/vomiting exhibited any dosage effect. The maximum tolerated dose of ara-C was 2400 mg/m2. There were 6 complete responses (5ALL), 5 partial responses (3 ALL), and 19 patients with no response or progressive disease. There was no dosage effect for response with 2 complete responses occurring at the lowest ara-C level. Responses were transient (1-3 months). 20/26 patients achieved a peak serum HU level >0.5 mM by 2 hours after the HU dose. The mean level at 2 hours was 0.57 mM (range 0.21-0.99 mM). This combination of HU and ara-C is tolerable and has efficacy in refractory leukemias. Responses at the lowest ara-C dose level suggests synergism. PMID:18458568
Dubowy, Ronald; Graham, Michael; Hakami, Nasrollah; Kletzel, Morris; Mahoney, Donald; Newman, Edward; Ravindranath, Yaddanapudi; Camitta, Bruce
2008-05-01
At concentrations >0.1 mM, hydroxyurea (HU) enhances the accumulation of cytosine arabinoside (ara-C) in leukemia cells in vitro. This study of children with refractory acute leukemia was designed to take advantage of this biochemical modulation. A fixed dose of HU and an escalating dose of ara-C were used. Oral HU (1200 mg/m2) was followed 2 hours later by ara-C (250-3100 mg/m2) intravenously in 15 minutes. The combination was given on days 1, 2, 3 and 8, 9, 10. Thirty-three children [26 acute lymphocytic leukemia (ALL), 7 acute nonlymphocytic leukemia] were treated; 29 received at least 1 full course. All patients developed grade 4 cytopenias. Other grade 3 to 4 toxicities included hyperbilirubinemia (2), elevated transaminases (3), transient gait disturbance (1), stomatitis (3), typhlitis (1), nausea/vomiting (9), and marrow aplasia >4 weeks (1). Three patients had intracranial bleeds while thrombocytopenic. Only liver toxicities and nausea/vomiting exhibited any dosage effect. The maximum tolerated dose of ara-C was 2400 mg/m2. There were 6 complete responses (5 ALL), 5 partial responses (3 ALL), and 19 patients with no response or progressive disease. There was no dosage effect for response with 2 complete responses occurring at the lowest ara-C level. Responses were transient (1 to 3 mo). Twenty of twenty-six patients achieved a peak serum HU level >0.5 mM by 2 hours after the HU dose. The mean level at 2 hours was 0.57 mM (range: 0.21 to 0.99 mM). This combination of HU and ara-C is tolerable and has efficacy in refractory leukemias. Responses at the lowest ara-C dose level suggests synergism.
Kuong, Kawai J.; Kuzminov, Andrei
2009-01-01
Hydroxyurea is a potent remedy against a variety of ailments and an efficient inhibitor of DNA synthesis, yet its pharmacology is unclear. Hydroxyurea acts in Escherichia coli by the same mechanism as it does in eukaryotes, via inhibition of ribonucleotide reductase. When examining a controversy about concentrations of hydroxyurea that prevent thymineless death in E. coli, we found instability in hydroxyurea solutions which avoided prior detection due to its peculiar nature. In contrast to freshly dissolved hydroxyurea, which did not affect respiration and was bacteriostatic, one-day-old hydroxyurea solutions inhibited respiration and were immediately bactericidal. Respiration was inhibited by two gasses, hydrogen cyanide (HCN) and nitric oxide (NO), whose appearance we detected in “aged” hydroxyurea stocks by GC-MS; however, neither gas was bactericidal. While determining the cause of toxicity, we found that hydroxyurea damages DNA directly. We also demonstrated accumulation of peroxides in hydroxyurea solutions by enzymatic assays, which explains the toxicity, as both NO and HCN are known to kill bacteria when combined with hydrogen peroxide. Remarkably, we found that bactericidal effects of NO + H2O2 and HCN + H2O2 mixtures were further synergistic. Accumulation of decomposition products in solutions of hydroxyurea may explain the broad therapeutic effects of this drug. PMID:19467244
TCD With Transfusions Changing to Hydroxyurea (TWiTCH): a multicentre, randomised controlled trial
Ware, Russell E.; Davis, Barry R.; Schultz, William H.; Brown, R. Clark; Aygun, Banu; Sarnaik, Sharada; Odame, Isaac; Fuh, Beng; George, Alex; Owen, William; Luchtman-Jones, Lori; Rogers, Zora R.; Hilliard, Lee; Gauger, Cynthia; Piccone, Connie; Lee, Margaret T.; Kwiatkowski, Janet L.; Jackson, Sherron; Miller, Scott T.; Roberts, Carla; Heeney, Matthew M.; Kalfa, Theodosia A.; Nelson, Stephen; Imran, Hamayun; Nottage, Kerri; Alvarez, Ofelia; Rhodes, Melissa; Thompson, Alexis A.; Rothman, Jennifer A.; Helton, Kathleen J.; Roberts, Donna; Coleman, Jamie; Bonner, Melanie J.; Kutlar, Abdullah; Patel, Niren; Wood, John; Piller, Linda; Wei, Peng; Luden, Judy; Mortier, Nicole A.; Stuber, Susan E.; Luban, Naomi L. C.; Cohen, Alan R.; Pressel, Sara; Adams, Robert J.
2017-01-01
Background For children with sickle cell anaemia and elevated transcranial Doppler (TCD) flow velocities, regular blood transfusions effectively prevent primary stroke, but must be continued indefinitely. The efficacy of hydroxyurea in this setting is unknown. Methods TWiTCH was a multicentre Phase III randomised open label, non-inferiority trial comparing standard treatment (transfusions) to alternative treatment (hydroxyurea) in children with abnormal TCD velocities but no severe vasculopathy. Iron overload was managed with chelation (Standard Arm) and serial phlebotomy (Alternative Arm). The primary study endpoint was the 24-month TCD velocity calculated from a general linear mixed model, with non-inferiority margin = 15 cm/sec. Findings Among 121 randomised participants (61 transfusions, 60 hydroxyurea), children on transfusions maintained <30% sickle haemoglobin, while those taking hydroxyurea (mean 27 mg/kg/day) averaged 25% fetal haemoglobin. The first scheduled interim analysis demonstrated non-inferiority, and the sponsor terminated the study. Final model-based TCD velocities (mean ± standard error) on Standard versus Alternative Arm were 143 ± 1.6 and 138 ± 1.6 cm/sec, respectively, with difference (95% CI) = 4.54 (0.10, 8.98), non-inferiority p=8.82 × 10−16 and post-hoc superiority p=0.023. Among 29 new neurological events adjudicated centrally by masked reviewers, no strokes occurred but there were 3 transient ischaemic attacks per arm. Exit brain MRI/MRA revealed no new cerebral infarcts in either arm, but worse vasculopathy in one participant (Standard Arm). Iron burden decreased more in the Alternative Arm, with ferritin difference −1047 ng/mL (−1524, −570), p<0.001 and liver iron difference −4.3 mg Fe/gm dry weight (−6.1, −2.5), p=0.001. Interpretation For high-risk children with sickle cell anaemia and abnormal TCD velocities, after four years of transfusions and without severe MRA vasculopathy, hydroxyurea therapy can substitute for chronic transfusions to maintain TCD velocities and help prevent primary stroke. PMID:26670617
McGann, Patrick T; Williams, Thomas N; Olupot-Olupot, Peter; Tomlinson, George A; Lane, Adam; Luís Reis da Fonseca, José; Kitenge, Robert; Mochamah, George; Wabwire, Ham; Stuber, Susan; Howard, Thad A; McElhinney, Kathryn; Aygun, Banu; Latham, Teresa; Santos, Brígida; Tshilolo, Léon; Ware, Russell E
2018-08-01
Despite its well-described safety and efficacy in the treatment of sickle cell anemia (SCA) in high-income settings, hydroxyurea remains largely unavailable in sub-Saharan Africa, where more than 75% of annual SCA births occur and many comorbidities exist. Realizing Effectiveness Across Continents with Hydroxyurea (REACH, ClinicalTrials.gov NCT01966731) is a prospective, Phase I/II open-label trial of hydroxyurea designed to evaluate the feasibility, safety, and benefits of hydroxyurea treatment for children with SCA in four sub-Saharan African countries. Following comprehensive training of local research teams, REACH was approved by local Ethics Committees and achieved full enrollment ahead of projections with 635 participants enrolled over a 30-month period, despite half of families living >12 km from their clinical site. At enrollment, study participants (age 5.4 ± 2.4 years) had substantial morbidity, including a history of vaso-occlusive pain (98%), transfusion (68%), malaria (85%), and stroke (6%). Significant differences in laboratory characteristics were noted across sites, with lower hemoglobin concentrations (P < .01) in Angola (7.2 ± 1.0 g/dL) and the DRC (7.0 ± 0.9 g/dL) compared to Kenya (7.4 ± 1.1 g/dL) and Uganda (7.5 ± 1.1 g/dL). Analysis of known genetic modifiers of SCA demonstrated a high frequency of α-thalassemia (58.4% with at least a single α-globin gene deletion) and G6PD deficiency (19.7% of males and 2.4% of females) across sites. The CAR β-globin haplotype was present in 99% of participants. The full enrollment to REACH confirms the feasibility of conducting high-quality SCA research in Africa; this study will provide vital information to guide safe and effective dosing of hydroxyurea for children with SCA living in Africa. © 2018 Wiley Periodicals, Inc.
Dissociative electron attachment to the radiosensitizing chemotherapeutic agent hydroxyurea
NASA Astrophysics Data System (ADS)
Huber, S. E.; Śmiałek, M. A.; Tanzer, K.; Denifl, S.
2016-06-01
Dissociative electron attachment to hydroxyurea was studied in the gas phase for electron energies ranging from zero to 9 eV in order to probe its radiosensitizing capabilities. The experiments were carried out using a hemispherical electron monochromator coupled with a quadrupole mass spectrometer. Diversified fragmentation of hydroxyurea was observed upon low energy electron attachment and here we highlight the major dissociation channels. Moreover, thermodynamic thresholds for various fragmentation reactions are reported to support the discussion of the experimental findings. The dominant dissociation channel, which was observed over a broad range of energies, is associated with formation of NCO-, water, and the amidogen (NH2) radical. The second and third most dominant dissociation channels are associated with formation of NCNH- and NHCONH2-, respectively, which are both directly related to formation of the highly reactive hydroxyl radical. Other ions observed with significant abundance in the mass spectra were NH2-/O-, OH-, CN-, HNOH-, NCONH2-, and ONHCONH2-.
Assessment of genotoxicity associated with hydroxyurea therapy in children with sickle cell anemia
Flanagan, Jonathan M.; Howard, Thad A.; Mortier, Nicole; Avlasevich, Svetlana L.; Smeltzer, Matthew P.; Wu, Song; Dertinger, Stephen D.; Ware, Russell E.
2018-01-01
Hydroxyurea induces fetal hemoglobin, improves laboratory parameters, and ameliorates clinical complications of sickle cell anemia (SCA), but its long-term efficacy and safety in this patient population remain incompletely defined. Although generally considered non-DNA reactive, an important safety concern is that hydroxyurea may indirectly cause genotoxic damage. To better address this safety issue of hydroxyurea in patients with SCA, we measured the production of micronuclei (MN) in red blood cells (RBC) as a marker of genotoxicity. Blood samples were collected from children with SCA enrolled in the Hydroxyurea Study of Long-term Effects (ClinicalTrials.gov NCT00305175). Flow cytometry quantified circulating MN-containing erythrocyte sub-populations before and during hydroxyurea exposure. The frequency of micronucleated reticulocytes (MN-CD71+) and micronucleated mature erythrocytes (MN-RBC) were then tested for associations with laboratory and clinical data. In cross-sectional analysis of 293 blood samples from 105 children with SCA and a median of 2 years of hydroxyurea therapy, exposure to hydroxyurea was associated with significantly increased frequencies of MN-CD71+ and MN-RBC compared to baseline. The increases were evident by 3 months of therapy, and did not escalate further with up to 12 years of continuous drug exposure. In prospective longitudinal analysis, substantial inter-individual variation in the effect of hydroxyurea on %MN-CD71+ was observed that was associated with the expected laboratory effects of hydroxyurea. In conclusion, clinically relevant exposure to hydroxyurea is associated with increased MN production consistent with erythroblast genotoxicity but with substantial inter-patient variability. Associations between increased %MN-CD71+ and laboratory benefits suggest that hydroxyurea effects on MN production may be related to individual patient sensitivity to hydroxyurea within the bone marrow. PMID:20230905
Organic anion transporting polypeptide 1B transporters modulate hydroxyurea pharmacokinetics.
Walker, Aisha L; Lancaster, Cynthia S; Finkelstein, David; Ware, Russell E; Sparreboom, Alex
2013-12-15
Hydroxyurea is currently the only FDA-approved drug that ameliorates the pathophysiology of sickle cell anemia. Unfortunately, substantial interpatient variability in the pharmacokinetics (PK) of hydroxyurea may result in variation of the drug's efficacy. However, little is known about mechanisms that modulate hydroxyurea PK. Recent in vitro studies identifying hydroxyurea as a substrate for organic anion transporting polypeptide (OATP1B) transporters prompted the current investigation assessing the role of OATP1B transporters in modulating hydroxyurea PK. Using wild-type and Oatp1b knockout (Oatp1b(-/-)) mice, hydroxyurea PK was analyzed in vivo by measuring [(14)C]hydroxyurea distribution in plasma, kidney, liver, urine, or the exhaled (14)CO2 metabolite. Plasma levels were significantly reduced by 20% in Oatp1b(-/-) mice compared with wild-type (area under the curve of 38.64 or 48.45 μg·h(-1)·ml(-1), respectively) after oral administration, whereas no difference was observed between groups following intravenous administration. Accumulation in the kidney was significantly decreased by twofold in Oatp1b(-/-) mice (356.9 vs. 748.1 pmol/g), which correlated with a significant decrease in urinary excretion. Hydroxyurea accumulation in the liver was also decreased (136.6 vs. 107.3 pmol/g in wild-type or Oatp1b(-/-) mice, respectively) correlating with a decrease in exhaled (14)CO2. These findings illustrate that deficiency of Oatp1b transporters alters the absorption, distribution, and elimination of hydroxyurea thus providing the first in vivo evidence that cell membrane transporters may play a significant role in modulating hydroxyurea PK. Future studies to investigate other transporters and their role in hydroxyurea disposition are warranted for understanding the sources of variation in hydroxyurea's PK.
Organic anion transporting polypeptide 1B transporters modulate hydroxyurea pharmacokinetics
Lancaster, Cynthia S.; Finkelstein, David; Ware, Russell E.; Sparreboom, Alex
2013-01-01
Hydroxyurea is currently the only FDA-approved drug that ameliorates the pathophysiology of sickle cell anemia. Unfortunately, substantial interpatient variability in the pharmacokinetics (PK) of hydroxyurea may result in variation of the drug's efficacy. However, little is known about mechanisms that modulate hydroxyurea PK. Recent in vitro studies identifying hydroxyurea as a substrate for organic anion transporting polypeptide (OATP1B) transporters prompted the current investigation assessing the role of OATP1B transporters in modulating hydroxyurea PK. Using wild-type and Oatp1b knockout (Oatp1b−/−) mice, hydroxyurea PK was analyzed in vivo by measuring [14C]hydroxyurea distribution in plasma, kidney, liver, urine, or the exhaled 14CO2 metabolite. Plasma levels were significantly reduced by 20% in Oatp1b−/− mice compared with wild-type (area under the curve of 38.64 or 48.45 μg·h−1·ml−1, respectively) after oral administration, whereas no difference was observed between groups following intravenous administration. Accumulation in the kidney was significantly decreased by twofold in Oatp1b−/− mice (356.9 vs. 748.1 pmol/g), which correlated with a significant decrease in urinary excretion. Hydroxyurea accumulation in the liver was also decreased (136.6 vs. 107.3 pmol/g in wild-type or Oatp1b−/− mice, respectively) correlating with a decrease in exhaled 14CO2. These findings illustrate that deficiency of Oatp1b transporters alters the absorption, distribution, and elimination of hydroxyurea thus providing the first in vivo evidence that cell membrane transporters may play a significant role in modulating hydroxyurea PK. Future studies to investigate other transporters and their role in hydroxyurea disposition are warranted for understanding the sources of variation in hydroxyurea's PK. PMID:23986199
Opoka, Robert O; Ndugwa, Christopher M; Latham, Teresa S; Lane, Adam; Hume, Heather A; Kasirye, Phillip; Hodges, James S; Ware, Russell E; John, Chandy C
2017-12-14
Hydroxyurea treatment is recommended for children with sickle cell anemia (SCA) living in high-resource malaria-free regions, but its safety and efficacy in malaria-endemic sub-Saharan Africa, where the greatest sickle-cell burden exists, remain unknown. In vitro studies suggest hydroxyurea could increase malaria severity, and hydroxyurea-associated neutropenia could worsen infections. NOHARM (Novel use Of Hydroxyurea in an African Region with Malaria) was a randomized, double-blinded, placebo-controlled trial conducted in malaria-endemic Uganda, comparing hydroxyurea to placebo at 20 ± 2.5 mg/kg per day for 12 months. The primary outcome was incidence of clinical malaria. Secondary outcomes included SCA-related adverse events (AEs), clinical and laboratory effects, and hematological toxicities. Children received either hydroxyurea (N = 104) or placebo (N = 103). Malaria incidence did not differ between children on hydroxyurea (0.05 episodes per child per year; 95% confidence interval [0.02, 0.13]) vs placebo (0.07 episodes per child per year [0.03, 0.16]); the hydroxyurea/placebo malaria incidence rate ratio was 0.7 ([0.2, 2.7]; P = .61). Time to infection also did not differ significantly between treatment arms. A composite SCA-related clinical outcome (vaso-occlusive painful crisis, dactylitis, acute chest syndrome, splenic sequestration, or blood transfusion) was less frequent with hydroxyurea (45%) than placebo (69%; P = .001). Children receiving hydroxyurea had significantly increased hemoglobin concentration and fetal hemoglobin, with decreased leukocytes and reticulocytes. Serious AEs, sepsis episodes, and dose-limiting toxicities were similar between treatment arms. Three deaths occurred (2 hydroxyurea, 1 placebo, and none from malaria). Hydroxyurea treatment appears safe for children with SCA living in malaria-endemic sub-Saharan Africa, without increased severe malaria, infections, or AEs. Hydroxyurea provides SCA-related laboratory and clinical efficacy, but optimal dosing and monitoring regimens for Africa remain undefined. This trial was registered at www.clinicaltrials.gov as #NCT01976416. © 2017 by The American Society of Hematology.
Impact of cycling cells and cell cycle regulation on Hydra regeneration.
Buzgariu, Wanda; Wenger, Yvan; Tcaciuc, Nina; Catunda-Lemos, Ana-Paula; Galliot, Brigitte
2018-01-15
Hydra tissues are made from three distinct populations of stem cells that continuously cycle and pause in G2 instead of G1. To characterize the role of cell proliferation after mid-gastric bisection, we have (i) used flow cytometry and classical markers to monitor cell cycle modulations, (ii) quantified the transcriptomic regulations of 202 genes associated with cell proliferation during head and foot regeneration, and (iii) compared the impact of anti-proliferative treatments on regeneration efficiency. We confirm two previously reported events: an early mitotic wave in head-regenerating tips, when few cell cycle genes are up-regulated, and an early-late wave of proliferation on the second day, preceded by the up-regulation of 17 cell cycle genes. These regulations appear more intense after mid-gastric bisection than after decapitation, suggesting a position-dependent regulation of cell proliferation during head regeneration. Hydroxyurea, which blocks S-phase progression, delays head regeneration when applied before but not after bisection. This result is consistent with the fact that the Hydra central region is enriched in G2-paused adult stem cells, poised to divide upon injury, thus forming a necessary constitutive pro-blastema. However a prolonged exposure to hydroxyurea does not block regeneration as cells can differentiate apical structures without traversing S-phase, and also escape in few days the hydroxyurea-induced S-phase blockade. Thus Hydra head regeneration, which is a fast event, is highly plastic, relying on large stocks of adult stem cells paused in G2 at amputation time, which immediately divide to proliferate and/or differentiate apical structures even when S-phase is blocked. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
NTP-CERHR monograph on the potential human reproductive and developmental effects of hydroxyurea.
2008-10-01
The National Toxicology Program (NTP) Center for the Evaluation of Risks to Human Reproduction (CERHR) conducted an evaluation of the potential for hydroxyurea to cause adverse effects on reproduction and development in humans. Hydroxyurea is a drug used to treat cancer, sickle cell disease, and thalassemia. It is the only treatment for sickle cell disease in children, aside from blood transfusion and, in severe cases, hematopoietic stem cell transplantation. Hydroxyurea is FDA-approved for use in adults with sickle cell anemia to reduce the frequency of painful crises and the need for blood transfusions. Hydroxyurea may be given to children and adults with sickle cell disease for an extended period of time or for repeated cycles of therapy. Treatment with hydroxyurea is associated with known side effects such as cytotoxicity and myelosuppression, and hydroxyurea is genotoxic (can damage DNA). CERHR selected hydroxyurea for evaluation because of: its increasing use for treatment of sickle cell disease in children and adults, knowledge that it inhibits DNA synthesis and is cytotoxic, and published evidence of reproductive and developmental toxicity in rodents. The results of this evaluation are published in the NTP-CERHR Monograph on Hydroxyurea, which includes the NTP Brief and Expert Panel Report on the Reproductive and Developmental Toxicity of Hydroxyurea. Additional information related to the evaluation process, including public comments received on the draft NTP Brief and the final expert panel report, are available on the CERHR website (http:// cerhr.niehs.nih.gov/). See hydroxyurea under "CERHR Chemicals" on the homepage or go directly to http://cerhr.niehs.nih.gov/chemicals/hydroxyurea/hydroxyurea-eval.html). The NTP reached the following conclusions on the possible effects of exposure to hydroxyurea on human reproduction or development. The possible levels of concern, from lowest to highest, are negligible concern, minimal concern, some concern, concern, and serious concern. The NTP expresses serious concern that exposure of men to therapeutic doses of hydroxyurea may adversely affect sperm production. This level of concern is for all males who have reached puberty. The NTP concurs with the Expert Panel that there is concern that exposure of pregnant women to hydroxyurea may result in birth defects, abnormalities of fetal growth, or abnormal postnatal development in offspring. The NTP concurs with the Expert Panel that there is minimal concern that exposure of children to therapeutic doses of hydroxyurea at 5 -15 years of age will adversely affect growth. NTP will transmit the NTP-CERHR Monograph on the Potential Human Reproductive and Developmental Effects of Hydroxyurea to federal and state agencies, interested parties, and the public and make it available in electronic PDF format on the CERHR web site (http://cerhr niehs nih gov) and in printed text or CD from CERHR.
ElAlfy, Mohsen Saleh; Adly, Amira Abdel Moneam; Ebeid, Fatma Soliman ElSayed; Eissa, Deena Samir; Ismail, Eman Abdel Rahman; Mohammed, Yasser Hassan; Ahmed, Manar Elsayed; Saad, Aya Sayed
2018-06-20
Sickle cell disease (SCD) is associated with alterations in immune phenotypes. CD4 + CD28 null T lymphocytes have pro-inflammatory functions and are linked to vascular diseases. To assess the percentage of CD4 + CD28 null T lymphocytes, natural killer cells (NK), and IFN-gamma levels, we compared 40 children and adolescents with SCD with 40 healthy controls and evaluated their relation to disease severity and response to therapy. Patients with SCD steady state were studied, focusing on history of frequent vaso-occlusive crisis, hydroxyurea therapy, and IFN-gamma levels. Analysis of CD4 + CD28 null T lymphocytes and NK cells was done by flow cytometry. Liver and cardiac iron overload were assessed. CD4 + CD28 null T lymphocytes, NK cells, and IFN-gamma levels were significantly higher in patients than controls. Patients with history of frequent vaso-occlusive crisis and those with vascular complications had higher percentage of CD4 + CD28 null T lymphocytes and IFN-gamma while levels were significantly lower among hydroxyurea-treated patients. CD4 + CD28 null T lymphocytes were positively correlated to transfusional iron input while these cells and IFN-gamma were negatively correlated to cardiac T2* and duration of hydroxyurea therapy. NK cells were correlated to HbS and indirect bilirubin. Increased expression of CD4 + CD28 null T lymphocytes highlights their role in immune dysfunction and pathophysiology of SCD complications.
Lebensburger, Jeffrey D.; Howard, Thad; Hu, Yunming; Pestina, Tamara I.; Gao, Geli; Johnson, Melissa; Zakharenko, Stanislav S.; Ware, Russell E.; Tuomanen, Elaine I.; Persons, Derek A.
2012-01-01
Sickle cell anemia is characterized by chronic hemolysis coupled with extensive vascular inflammation. This inflammatory state also mechanistically promotes a high risk of lethal, invasive pneumococcal infection. Current treatments to reduce vaso-occlusive complications include chronic hydroxyurea therapy to induce fetal hemoglobin. Because hydroxyurea also reduces leukocytosis, an understanding of the impact of this treatment on pneumococcal pathogenesis is needed. Using a sickle cell mouse model of pneumococcal pneumonia and sepsis, administration of hydroxyurea was found to significantly improve survival. Hydroxyurea treatment decreased neutrophil extravasation into the infected lung coincident with significantly reduced levels of E-selectin in serum and on pulmonary epithelia. The protective effect of hydroxyurea was abrogated in mice deficient in E-selectin. The decrease in E-selectin levels was also evident in human sickle cell patients receiving hydroxyurea therapy. These data indicate that in addition to induction of fetal hemoglobin, hydroxyurea attenuates leukocyte–endothelial interactions in sickle cell anemia, resulting in protection against lethal pneumococcal sepsis. PMID:22130804
Kirito, Keita; Suzuki, Kenshi; Miyamura, Koichi; Takeuchi, Masahiro; Handa, Hiroshi; Okamoto, Shinichiro; Gadbaw, Brian; Yamauchi, Kyosuke; Amagasaki, Taro; Ito, Kazuo; Hino, Masayuki
2018-02-01
Ruxolitinib, a potent JAK1/JAK2 inhibitor, was found to be superior to the best available therapy (BAT) in controlling hematocrit, reducing splenomegaly, and improving symptoms in the phase 3 RESPONSE study of patients with polycythemia vera with splenomegaly who experienced an inadequate response to or adverse effects from hydroxyurea. We report findings from a subgroup analysis of Japanese patients in RESPONSE (n = 18). The composite response rate (hematocrit control and spleen response) was higher in patients receiving ruxolitinib (50.0%) than in those receiving BAT (8.3%). A total of 50.0% of patients randomized to ruxolitinib achieved a spleen response vs 8.3% of those receiving BAT; 100 and 33.3% of patients in the respective groups achieved hematocrit control, with mean hematocrit in ruxolitinib-treated patients remaining stable at < 45% throughout the study. Similarly, a higher proportion of ruxolitinib-treated patients achieved complete hematologic remission (33.3 vs 16.7%). Ruxolitinib also led to rapid improvements in pruritus. All responses with ruxolitinib were durable to week 80, and its safety profile was consistent with that in the overall study. These findings suggest that ruxolitinib is an effective and well-tolerated treatment option for Japanese patients with polycythemia vera with an inadequate response to or adverse effects from hydroxyurea.
Optimizing hydroxyurea therapy for sickle cell anemia.
Ware, Russell E
2015-01-01
Hydroxyurea has proven efficacy in numerous clinical trials as a disease-modifying treatment for patients with sickle cell anemia (SCA) but is currently under-used in clinical practice. To improve the effectiveness of hydroxyurea therapy, efforts should be directed toward broadening the clinical treatment indications, optimizing the daily dosage, and emphasizing the benefits of early and extended treatment. Here, various issues related to hydroxyurea treatment are discussed, focusing on both published evidence and clinical experience. Specific guidance is provided regarding important but potentially unfamiliar aspects of hydroxyurea treatment for SCA, such as escalating to maximum tolerated dose, treating in the setting of cerebrovascular disease, switching from chronic transfusions to hydroxyurea, and using serial phlebotomy to alleviate iron overload. Future research directions to optimize hydroxyurea therapy are also discussed, including personalized dosing based on pharmacokinetic modeling, prediction of fetal hemoglobin responses based on pharmacogenomics, and the risks and benefits of hydroxyurea for non-SCA genotypes and during pregnancy/lactation. Another critical initiative is the introduction of hydroxyurea safely and effectively into global regions that have a high disease burden of SCA but limited resources, such as sub-Saharan Africa, the Caribbean, and India. Final considerations emphasize the long-term goal of optimizing hydroxyurea therapy, which is to help treatment become accepted as standard of care for all patients with SCA. © 2015 by The American Society of Hematology. All rights reserved.
[Hydroxyurea-induced pneumonia].
Girard, A; Ricordel, C; Poullot, E; Claeyssen, V; Decaux, O; Desrues, B; Delaval, P; Jouneau, S
2014-05-01
Hydroxyurea is an antimetabolite drug used in the treatment of myeloproliferative disorders. Common adverse effects include haematological, gastrointestinal cutaneous manifestations, and fever. Hydroxyurea-induced pneumonitis is unusual. A female patient was treated with hydroxyurea for polycythemia vera. She was admitted 20 days after commencing treatment with a high fever, productive cough, clear sputum and nausea. A chest CT-scan showed diffuse ground-glass opacities. Microbiological investigations were negative. The symptoms disappeared a few days after discontinuation of the drug and rechallenge led to a relapse of symptoms. Our case and 15 earlier cases of hydroxyurea-induced pneumonitis are reviewed. Two patterns of this disease may exist: an acute febrile form occurring within 1 month of introduction of hydroxyurea and a subacute form without fever. Even if uncommon, one should be aware of this complication of hydroxyurea. Copyright © 2013. Published by Elsevier Masson SAS.
Dissociative electron attachment to the radiosensitizing chemotherapeutic agent hydroxyurea
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huber, S. E.; Tanzer, K.; Denifl, S.
Dissociative electron attachment to hydroxyurea was studied in the gas phase for electron energies ranging from zero to 9 eV in order to probe its radiosensitizing capabilities. The experiments were carried out using a hemispherical electron monochromator coupled with a quadrupole mass spectrometer. Diversified fragmentation of hydroxyurea was observed upon low energy electron attachment and here we highlight the major dissociation channels. Moreover, thermodynamic thresholds for various fragmentation reactions are reported to support the discussion of the experimental findings. The dominant dissociation channel, which was observed over a broad range of energies, is associated with formation of NCO{sup −}, water,more » and the amidogen (NH{sub 2}) radical. The second and third most dominant dissociation channels are associated with formation of NCNH{sup −} and NHCONH{sub 2}{sup −}, respectively, which are both directly related to formation of the highly reactive hydroxyl radical. Other ions observed with significant abundance in the mass spectra were NH{sub 2}{sup −}/O{sup −}, OH{sup −}, CN{sup −}, HNOH{sup −}, NCONH{sub 2}{sup −}, and ONHCONH{sub 2}{sup −}.« less
Alvarez-Larrán, Alberto; Pérez-Encinas, Manuel; Ferrer-Marín, Francisca; Hernández-Boluda, Juan Carlos; Ramírez, María José; Martínez-López, Joaquín; Magro, Elena; Cruz, Yasmina; Mata, María Isabel; Aragües, Pilar; Fox, María Laura; Cuevas, Beatriz; Montesdeoca, Sara; Hernández-Rivas, José Angel; García-Gutiérrez, Valentín; Gómez-Casares, María Teresa; Steegmann, Juan Luis; Durán, María Antonia; Gómez, Montse; Kerguelen, Ana; Bárez, Abelardo; García, Mari Carmen; Boqué, Concepción; Raya, José María; Martínez, Clara; Albors, Manuel; García, Francesc; Burgaleta, Carmen; Besses, Carlos
2017-01-01
Hematocrit control below 45% is associated with a lower rate of thrombosis in polycythemia vera. In patients receiving hydroxyurea, this target can be achieved with hydroxyurea alone or with the combination of hydroxyurea plus phlebotomies. However, the clinical implications of phlebotomy requirement under hydroxyurea therapy are unknown. The aim of this study was to evaluate the need for additional phlebotomies during the first five years of hydroxyurea therapy in 533 patients with polycythemia vera. Patients requiring 3 or more phlebotomies per year (n=85, 16%) showed a worse hematocrit control than those requiring 2 or less phlebotomies per year (n=448, 84%). There were no significant differences between the two study groups regarding leukocyte and platelet counts. Patients requiring 3 or more phlebotomies per year received significantly higher doses of hydroxyurea than the remaining patients. A significant higher rate of thrombosis was found in patients treated with hydroxyurea plus 3 or more phlebotomies per year compared to hydroxyurea with 0–2 phlebotomies per year (20.5% vs. 5.3% at 3 years; P<0.0001). In multivariate analysis, independent risk factors for thrombosis were phlebotomy dependency (HR: 3.3, 95%CI: 1.5–6.9; P=0.002) and thrombosis at diagnosis (HR: 4.7, 95%CI: 2.3–9.8; P<0.0001). The proportion of patients fulfilling the European LeukemiaNet criteria of resistance/intolerance to hydroxyurea was significantly higher in the group requiring 3 or more phlebotomies per year (18.7% vs. 7.1%; P=0.001) mainly due to extrahematologic toxicity. In conclusion, phlebotomy requirement under hydroxyurea therapy identifies a subset of patients with increased proliferation of polycythemia vera and higher risk of thrombosis. PMID:27686377
Alvarez-Larrán, Alberto; Pérez-Encinas, Manuel; Ferrer-Marín, Francisca; Hernández-Boluda, Juan Carlos; Ramírez, María José; Martínez-López, Joaquín; Magro, Elena; Cruz, Yasmina; Mata, María Isabel; Aragües, Pilar; Fox, María Laura; Cuevas, Beatriz; Montesdeoca, Sara; Hernández-Rivas, José Angel; García-Gutiérrez, Valentín; Gómez-Casares, María Teresa; Steegmann, Juan Luis; Durán, María Antonia; Gómez, Montse; Kerguelen, Ana; Bárez, Abelardo; García, Mari Carmen; Boqué, Concepción; Raya, José María; Martínez, Clara; Albors, Manuel; García, Francesc; Burgaleta, Carmen; Besses, Carlos
2017-01-01
Hematocrit control below 45% is associated with a lower rate of thrombosis in polycythemia vera. In patients receiving hydroxyurea, this target can be achieved with hydroxyurea alone or with the combination of hydroxyurea plus phlebotomies. However, the clinical implications of phlebotomy requirement under hydroxyurea therapy are unknown. The aim of this study was to evaluate the need for additional phlebotomies during the first five years of hydroxyurea therapy in 533 patients with polycythemia vera. Patients requiring 3 or more phlebotomies per year (n=85, 16%) showed a worse hematocrit control than those requiring 2 or less phlebotomies per year (n=448, 84%). There were no significant differences between the two study groups regarding leukocyte and platelet counts. Patients requiring 3 or more phlebotomies per year received significantly higher doses of hydroxyurea than the remaining patients. A significant higher rate of thrombosis was found in patients treated with hydroxyurea plus 3 or more phlebotomies per year compared to hydroxyurea with 0-2 phlebotomies per year (20.5% vs. 5.3% at 3 years; P<0.0001). In multivariate analysis, independent risk factors for thrombosis were phlebotomy dependency (HR: 3.3, 95%CI: 1.5-6.9; P=0.002) and thrombosis at diagnosis (HR: 4.7, 95%CI: 2.3-9.8; P<0.0001). The proportion of patients fulfilling the European LeukemiaNet criteria of resistance/intolerance to hydroxyurea was significantly higher in the group requiring 3 or more phlebotomies per year (18.7% vs. 7.1%; P=0.001) mainly due to extrahematologic toxicity. In conclusion, phlebotomy requirement under hydroxyurea therapy identifies a subset of patients with increased proliferation of polycythemia vera and higher risk of thrombosis. Copyright© Ferrata Storti Foundation.
Hydroxyurea-induced oral ulceration.
Badawi, Maha; Almazrooa, Soulafa; Azher, Fatima; Alsayes, Fatin
2015-12-01
Hydroxyurea is an antimetabolite that is widely used in the treatment of many benign and malignant conditions. This drug is usually well tolerated but has a number of side effects that vary in incidence. In cases of clinically significant adverse events, hydroxyurea is usually discontinued either temporarily or permanently, depending on treatment need versus harm caused by side effects. Here, we report a case of oral ulceration associated with hydroxyurea treatment in a patient who had chronic myelogenous leukemia. The patient rapidly developed an oral ulcer 12 days after administration of the drug. Hydroxyurea was discontinued, and the oral lesion appreciably decreased in size and severity. Physicians and dentists should be aware of the association between hydroxyurea and oral lesions. Copyright © 2015 Elsevier Inc. All rights reserved.
Immunologic Effects of Hydroxyurea in Sickle Cell Anemia
Lederman, Howard M.; Connolly, Margaret A.; Kalpatthi, Ram; Ware, Russell E.; Wang, Winfred C.; Luchtman-Jones, Lori; Waclawiw, Myron; Goldsmith, Jonathan C.; Swift, Andrea
2014-01-01
BACKGROUND AND OBJECTIVE: Susceptibility to encapsulated bacteria is well known in sickle cell disease (SCD). Hydroxyurea use is common in adults and children with SCD, but little is known about hydroxyurea’s effects on immune function in SCD. Because hydroxyurea inhibits ribonucleotide reductase, causing cell cycle arrest at the G1–S interface, we postulated that hydroxyurea might delay transition from naive to memory T cells, with inhibition of immunologic maturation and vaccine responses. METHODS: T-cell subsets, naive and memory T cells, and antibody responses to pneumococcal and measles, mumps, and rubella vaccines were measured among participants in a multicenter, randomized, double-blind, placebo-controlled trial of hydroxyurea in infants and young children with SCD (BABY HUG). RESULTS: Compared with placebo, hydroxyurea treatment resulted in significantly lower total lymphocyte, CD4, and memory T-cell counts; however, these numbers were still within the range of historical healthy controls. Antibody responses to pneumococcal vaccination were not affected, but a delay in achieving protective measles antibody levels occurred in the hydroxyurea group. Antibody levels to measles, mumps, and rubella showed no differences between groups at exit, indicating that effective immunization can be achieved despite hydroxyurea use. CONCLUSIONS: Hydroxyurea does not appear to have significant deleterious effects on the immune function of infants and children with SCD. Additional assessments of lymphocyte parameters of hydroxyurea-treated children may be warranted. No changes in current immunization schedules are recommended; however, for endemic disease or epidemics, adherence to accelerated immunization schedules for the measles, mumps, and rubella vaccine should be reinforced. PMID:25180279
Steward, Shirley; Howard, Thad A.; Mortier, Nicole; Smeltzer, Matthew; Wang, Yong-Dong; Ware, Russell E.
2011-01-01
Hydroxyurea has been shown to be efficacious for the treatment of sickle cell anemia (SCA), primarily through the induction of fetal hemoglobin (HbF). However, the exact mechanisms by which hydroxyurea can induce HbF remain incompletely defined, although direct transcriptional effects and altered cell cycle kinetics have been proposed. In this study, we investigated potential epigenetic and alternative molecular mechanisms of hydroxyurea-mediated HbF induction by examining methylation patterns within the Gγ-globin promoter and miRNA expression within primary CD71+ erythrocytes of patients with SCA, both at baseline before beginning hydroxyurea therapy and after reaching maximum tolerated dose (MTD). Using both cross-sectional analysis and paired-sample analysis, we found that the highly methylated Gγ-globin promoter was inversely correlated to baseline HbF levels, but only slightly altered by hydroxyurea treatment. Conversely, expression of several specific miRNAs was significantly increased after hydroxyurea treatment, and expression of miR-26b and miR-151-3p were both associated with HbF levels at MTD. The significant associations identified in these studies suggest that methylation may be important for regulation of baseline HbF, but not after hydroxyurea treatment, whereas changes in miRNA expression may be associated with hydroxyurea-mediated HbF induction. This study was registered at ClinicalTrials.gov (NCT00305175). PMID:21921042
Adewoyin, Ademola Samson; Oghuvwu, Omokiniovo Sunday; Awodu, Omolade Augustina
2017-03-01
The clinical prospects of hydroxyurea therapy in the management of sickle cell disease (SCD) require evaluation in the Nigerian setting to develop indigenous guidelines. This survey examines the pattern of hydroxyurea therapy, its clinico-haematologic benefits and safety profile in Nigerian SCD subjects. A cross sectional pilot survey was carried out among 60 adult SCD subjects over 3 months. Data on clinical phenotypes, relevant haematological parameters and details of hydroxyurea therapy were obtained using a structured questionnaire through an interview process and case file review. The median age was 30 years. Thirty-four (56.7%) of the subjects are aware of hydroxyurea therapy in SCD. Twenty-four (40%) SCD patients had previously used hydroxyurea. Only 4 subjects were fully compliant. Reasons for non-compliance included poor knowledge and lack of funds. In particular, hydroxyurea reduced leucocyte count and increased mean red cell volume (MCV) in compliant subjects. Hydroxyurea use is low among Nigerian SCD subjects despite its proven efficacy/clinical prospects in the developed nations. Large scale multicenter studies and clinical trials are needed to form a basis for developing standard local treatment protocol for its use.
Worley, B; Glassman, S J
2016-03-01
Hydroxyurea is used in essential thrombocythaemia to lower thromboembolic risk. Cutaneous adverse effects from hydroxyurea are diverse. Small vessel vasculitis has been rarely reported, and the coexistence of several different morphologies has not been described. We report a case of acral keratoses, psoriasiform plaques and leucocytoclastic vasculitis (LCV) in a patient with essential thrombocythaemia. A 69-year-old woman developed a confusing array of skin lesions including keratotic papules, psoriasiform plaques and keratoderma 4 years after commencing hydroxyurea therapy. The initial diagnosis was hand and foot psoriasis, but lesions were resistant to therapy. With an increase in the dose of hydroxyurea, the lesions ulcerated. Skin biopsies taken from different sites indicated different diagnoses, including LCV. Discontinuation of hydroxyurea yielded rapid improvement. Although the most commonly reported cutaneous adverse effect from hydroxyurea is leg ulceration, this can be preceded or accompanied by less dramatic skin lesions. Unless recognized, delayed diagnosis and lesion progression can occur. © 2015 British Association of Dermatologists.
Transcellular movement of hydroxyurea is mediated by specific solute carrier transporters
Walker, Aisha L.; Franke, Ryan M.; Sparreboom, Alex; Ware, Russell E.
2015-01-01
Objective Hydroxyurea has proven laboratory and clinical therapeutic benefits for sickle cell anemia (SCA) and other diseases, yet many questions remain regarding its in vivo pharmacokinetic and pharmacodynamic profiles. Previous reports suggest that hydroxyurea passively diffuses across cells, but its observed rapid absorption and distribution are more consistent with facilitated or active transport. We investigated the potential role of solute carrier (SLC) transporters in cellular uptake and accumulation of hydroxyurea. Materials and Methods Passive diffusion of hydroxyurea across cell membranes was determined using the parallel artificial membrane permeability assay. SLC transporter screens were conducted using in vitro intracellular drug accumulation and transcellular transport assays in cell lines and oocytes overexpressing SLC transporters. Gene expression of SLC transporters was measured by real-time PCR in human tissues and cell lines. Results Hydroxyurea had minimal diffusion across a lipid bilayer but was a substrate for 5 different SLC transporters belonging to the OCTN and OATP families of transporters and urea transporters A and B. Further characterization of hydroxyurea transport revealed that cellular uptake by OATP1B3 is time and temperature dependent and inhibited by known substrates of OATP1B3. Urea transporters A and B are expressed differentially in human tissues and erythroid cells, and transport hydroxyurea bidirectionally via facilitated diffusion. Conclusions These studies provide new insight into drug transport proteins that may be involved in the in vivo absorption, cellular distribution, and elimination of hydroxyurea. Elucidation of hydroxyurea transcellular movement should improve our understanding of its pharmacokinetics and pharmacodynamics, and may help explain some of the inter-patient drug variability observed in patients with SCA. PMID:21256917
Study on reduction and back extraction of Pu(IV) by urea derivatives in nitric acid conditions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ye, G.A.; Xiao, S.T.; Yan, T.H.
2013-07-01
The reduction kinetics of Pu(IV) by hydroxyl-semicarbazide (HSC), hydroxyurea (HU) and di-hydroxyurea (DHU) in nitric acid solutions were investigated separately with adequate kinetic equations. In addition, counter-current cascade experiments were conducted for Pu split from U in nitric acid media using three kinds of reductant, respectively. The results show that urea derivatives as a kind of novel salt-free reductant can reduce Pu(IV) to Pu(III) rapidly in the nitric acid solutions. The stripping experimental results showed that Pu(IV) in the organic phase can be stripped rapidly to the aqueous phase by the urea derivatives, and the separation factors of plutonium /uraniummore » can reach more than 10{sup 4}. This indicates that urea derivatives is a kind of promising salt-free agent for uranium/plutonium separation. In addition, the complexing effect of HSC with Np(IV) was revealed, and Np(IV) can be back-extracted by HSC with a separation factor of about 20.« less
Anagrelide compared with hydroxyurea in essential thrombocythemia: a meta-analysis.
Samuelson, Bethany; Chai-Adisaksopha, Chatree; Garcia, David
2015-11-01
Cytoreductive therapy, with or without low-dose aspirin, is the mainstay of thrombotic risk reduction in patients with essential thrombocythemia (ET), but the optimal choice of agent remains unclear. The aim of this study was to meta-analyze currently available data comparing anagrelide to hydroxyurea for reduction of rates of thrombosis, bleeding and death among patients with ET. A literature search for randomized, controlled trials comparing anagrelide to hydroxyurea among patients with ET revealed two published studies. Statistical analysis was performed using fixed effects meta-analysis. Rates of thrombosis were similar between patients treated with hydroxyurea vs anagrelide (RR 0.86, 95 % CI 0.64-1.16). Rates of major bleeding were lower in patients treated with hydroxyurea (RR 0.37, 95 % CI 0.18-0.75). Rates of progression to acute myeloid leukemia were not statistically different (RR 1.50, 95 % CI 0.43-5.29). The composite of thrombosis, major bleeding and death favored hydroxyurea (RR 0.78, 95 % CI 0.63-0.97). In conclusion, our analysis supports use of hydroxyurea as a first-line cytoreductive agent for patients with ET, based largely on decreased rates of major bleeding. Anagrelide appears to be equally effective for protection against thrombotic events and may be an appropriate alternative for patients who are intolerant of hydroxyurea.
Despotovic, Jenny M.; Mortier, Nicole A.; Flanagan, Jonathan M.; He, Jin; Smeltzer, Matthew P.; Kimble, Amy C.; Aygun, Banu; Wu, Song; Howard, Thad; Sparreboom, Alex
2011-01-01
Hydroxyurea therapy has proven laboratory and clinical efficacies for children with sickle cell anemia (SCA). When administered at maximum tolerated dose (MTD), hydroxyurea increases fetal hemoglobin (HbF) to levels ranging from 10% to 40%. However, interpatient variability of percentage of HbF (%HbF) response is high, MTD itself is variable, and accurate predictors of hydroxyurea responses do not currently exist. HUSTLE (NCT00305175) was designed to provide first-dose pharmacokinetics (PK) data for children with SCA initiating hydroxyurea therapy, to investigate pharmacodynamics (PD) parameters, including HbF response and MTD after standardized dose escalation, and to evaluate pharmacogenetics influences on PK and PD parameters. For 87 children with first-dose PK studies, substantial interpatient variability was observed, plus a novel oral absorption phenotype (rapid or slow) that influenced serum hydroxyurea levels and total hydroxyurea exposure. PD responses in 174 subjects were robust and similar to previous cohorts; %HbF at MTD was best predicted by 5 variables, including baseline %HbF, whereas MTD was best predicted by 5 variables, including serum creatinine. Pharmacogenetics analysis showed single nucleotide polymorphisms influencing baseline %HbF, including 5 within BCL11A, but none influencing MTD %HbF or dose. Accurate prediction of hydroxyurea treatment responses for SCA remains a worthy but elusive goal. PMID:21876119
Tun, Aung Myint; Naing, Ei Ei; Tun, Nay Min; Guevara, Elizabeth
2015-09-30
It is well known that hydroxyurea can cause pancytopaenia secondary to bone marrow suppression, which is reversible with short-term discontinuation of the therapy. However, it is important to note that bone marrow suppressive effects caused by hydroxyurea could be easily potentiated in patients with sickle cell anaemia complicated by chronic kidney disease (CKD). We present a case of a Jehovah's Witness with sickle cell anaemia, who developed severe bone marrow suppression due to the combined effects of hydroxyurea and CKD, resulting in a prolonged recovery period after discontinuation of hydroxyurea. 2015 BMJ Publishing Group Ltd.
Badawy, Sherif M; Thompson, Alexis A; Lai, Jin-Shei; Penedo, Frank J; Rychlik, Karen; Liem, Robert I
2017-07-05
Sickle cell disease (SCD) patients have impaired domains of health-related quality of life (HRQOL). Hydroxyurea is safe and efficacious in SCD; however, adherence is suboptimal, and patients' perceptions are poorly understood amongst adolescents and young adults (AYA). Study objectives were to: (1) examine patients' perceptions of SCD and hydroxyurea; and (2) explore the relationship of their perceptions to clinical characteristics, HRQOL domains and hydroxyurea adherence. Thirty-four SCD patients on hydroxyurea (≥6 months) participated in a single-institution study. Study measures included Brief-Illness Perceptions Questionnaire, ©Modified Morisky Adherence Scale 8-items, and Patient Reported Outcomes Measurement Information System (PROMIS®). We assessed the relationship of patients' perceptions to hydroxyurea adherence using Wilcoxon rank-sum test, the number of hospitalizations using Kruskal-Wallis test, and the number of ED visits, adherence level, HRQOL domain scores using Spearman's rho correlations. We conducted a sub-analysis in HbSS patients to evaluate the relationship of patients' perceptions to laboratory markers of hydroxyurea adherence. Participants were 59% male and 91% Black, and had a median age of 13.5 (range 12-18) years. Participants with ≥4 hospitalizations over 1-year prior (using electronic medical chart review) reported more negative perceptions of SCD-related symptoms and emotional response, and perceived hydroxyurea as less beneficial; all p-values ≤0.01. Most participants (74%) reported low hydroxyurea adherence. Participants with higher hydroxyurea adherence perceived more hydroxyurea benefits (r s = 0.44, p < 0.01) and had better emotional response to SCD (r s = -0.44, p = 0.01). In a sub-analysis of HbSS patients, perceived benefits of hydroxyurea positively correlated with HbF (r s = 0.37, p = 0.05) and MCV values (r s = 0.35, p = 0.05). Participants with more negative perceptions of SCD-related consequences, concerns, and emotional response, and fewer perceived hydroxyurea benefits reported worse fatigue (r s = 0.68; r s = 0.44; r s = 0.74; r s = -0.60), pain (r s = 0.56; r s = 0.54; r s = 0.63; r s = -0.39), anxiety (r s = 0.55; r s = 0.58; r s = 0.56; r s = -0.47), and depression (r s = 0.64; r s = 0.49; r s = 0.70; r s = -0.62), respectively, all p-values <0.05. Dynamics influencing hydroxyurea adherence are multifactorial, and understanding patients' perceptions is critical to overcoming adherence barriers. Patients' favorable perceptions correlated with greater adherence and better HRQOL domain scores. Prospective evaluation of patients' perceptions of SCD and hydroxyurea in relation adherence, HRQOL domains and clinical outcomes is warranted.
Feiner, Rose R.; Coward, Joe E.; Rosenkranz, Herbert S.
1973-01-01
Hydroxyurea-sensitive strains of Staphylococcus epidermidis and Micrococcus lysodeikticus showed marked thickening of cell walls and reduction in deoxyribonucleic acid synthesis when grown in the presence of hydroxyurea. Images PMID:4790602
Macrocytosis secondary to hydroxyurea therapy.
Conrado, Francisco O; Weeden, Amy L; Speas, Abbie L; Leissinger, Mary K
2017-09-01
A 10-year-old, male neutered Shetland Sheepdog was presented to the University of Florida for evaluation of a well-granulated mast cell tumor. Hydroxyurea therapy was instituted and serial CBCs showed persistent mild anemia and macrocytosis without a corresponding increase in polychromasia. The dog's MCV increased progressively, reaching its highest value of 100.0 fL after 6 months of treatment, and a diagnosis of macrocytosis associated with hydroxyurea therapy was made. The dog's increase in MCV was prominent, and rapidly decreased after the drug was discontinued, consistent with previous observations in human and canine subjects treated with hydroxyurea. Hydroxyurea is a cytotoxic chemotherapeutic agent used in a variety of conditions in human and veterinary medicine, and megaloblastic changes associated with its use have been described in multiple species. This report shows that hydroxyurea treatment is a differential diagnosis for prominent macrocytosis in dogs in the absence of other signs of erythrocyte regeneration. © 2017 American Society for Veterinary Clinical Pathology.
Hydroxyurea is associated with lower costs of care of young children with sickle cell anemia.
Wang, Winfred C; Oyeku, Suzette O; Luo, Zhaoyu; Boulet, Sheree L; Miller, Scott T; Casella, James F; Fish, Billie; Thompson, Bruce W; Grosse, Scott D
2013-10-01
In the BABY HUG trial, young children with sickle cell anemia randomized to receive hydroxyurea had fewer episodes of pain, hospitalization, and transfusions. With anticipated broader use of hydroxyurea in this population, we sought to estimate medical costs of care in treated versus untreated children. The BABY HUG database was used to compare inpatient events in subjects receiving hydroxyurea with those receiving placebo. Unit costs were estimated from the 2009 MarketScan Multi-state Medicaid Database for children with sickle cell disease, aged 1 to 3 years. Inpatient costs were based on length of hospital stay, modified by the occurrence of acute chest syndrome, splenic sequestration, or transfusion. Outpatient expenses were based on the schedule required for BABY HUG and a "standard" schedule for 1- to 3-year-olds with sickle cell anemia. There were 232 hospitalizations in the subjects receiving hydroxyurea and 324 in those on placebo; length of hospital stay was similar in the 2 groups. Estimated outpatient expenses were greater in those receiving hydroxyurea, but these were overshadowed by inpatient costs. The total estimated annual cost for those on hydroxyurea ($11 072) was 21% less than the cost of those on placebo ($13 962; P = .038). Savings on inpatient care resulted in a significantly lower overall estimated medical care cost for young children with sickle cell anemia who were receiving hydroxyurea compared with those receiving placebo. Because cost savings are likely to increase with age, these data provide additional support for broad use of hydroxyurea treatment in this population.
Deprenyl Enhances the Teratogenicity of Hydroxyurea in Organogenesis Stage Mouse Embryos
Schlisser, Ava E.; Hales, Barbara F.
2013-01-01
Hydroxyurea, an antineoplastic drug, is a model teratogen. The administration of hydroxyurea to CD1 mice on gestation day 9 induces oxidative stress, increasing the formation of 4-hydroxy-2-nonenal adducts to redox-sensitive proteins such as glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in the caudal region of the embryo. GAPDH catalytic activity is reduced, and its translocation into the nucleus is increased. Because the nuclear translocation of GAPDH is associated with oxidative stress–induced cell death, we hypothesized that this translocation plays a role in mediating the teratogenicity of hydroxyurea. Deprenyl (also known as selegiline), a drug used as a neuroprotectant in Parkinson’s disease, inhibits the nuclear translocation of GAPDH. Hence, timed pregnant CD1 mice were treated with deprenyl (10mg/kg) on gestation day 9 followed by the administration of hydroxyurea (400 or 600mg/kg). Deprenyl treatment significantly decreased the hydroxyurea-induced nuclear translocation of GAPDH in the caudal lumbosacral somites. Deprenyl enhanced hydroxyurea-mediated caudal malformations, inducing specifically limb reduction, digit anomalies, tail defects, and lumbosacral vertebral abnormalities. Deprenyl did not augment the hydroxyurea-induced inhibition of glycolysis or alter the ratio of oxidized to reduced glutathione. However, it did dramatically increase cleaved caspase-3 in embryos. These data suggest that nuclear GAPDH plays an important, region-specific, role in teratogen-exposed embryos. Deprenyl exacerbated the developmental outcome of hydroxyurea exposure by a mechanism that is independent of oxidative stress. Although the administration of deprenyl alone did not affect pregnancy outcome, this drug may have adverse consequences when combined with exposures that increase the risk of malformations. PMID:23696560
Hydroxyurea Is Associated With Lower Costs of Care of Young Children With Sickle Cell Anemia
Oyeku, Suzette O.; Luo, Zhaoyu; Boulet, Sheree L.; Miller, Scott T.; Casella, James F.; Fish, Billie; Thompson, Bruce W.; Grosse, Scott D.
2013-01-01
BACKGROUND AND OBJECTIVE: In the BABY HUG trial, young children with sickle cell anemia randomized to receive hydroxyurea had fewer episodes of pain, hospitalization, and transfusions. With anticipated broader use of hydroxyurea in this population, we sought to estimate medical costs of care in treated versus untreated children. METHODS: The BABY HUG database was used to compare inpatient events in subjects receiving hydroxyurea with those receiving placebo. Unit costs were estimated from the 2009 MarketScan Multi-state Medicaid Database for children with sickle cell disease, aged 1 to 3 years. Inpatient costs were based on length of hospital stay, modified by the occurrence of acute chest syndrome, splenic sequestration, or transfusion. Outpatient expenses were based on the schedule required for BABY HUG and a “standard” schedule for 1- to 3-year-olds with sickle cell anemia. RESULTS: There were 232 hospitalizations in the subjects receiving hydroxyurea and 324 in those on placebo; length of hospital stay was similar in the 2 groups. Estimated outpatient expenses were greater in those receiving hydroxyurea, but these were overshadowed by inpatient costs. The total estimated annual cost for those on hydroxyurea ($11 072) was 21% less than the cost of those on placebo ($13 962; P = .038). CONCLUSIONS: Savings on inpatient care resulted in a significantly lower overall estimated medical care cost for young children with sickle cell anemia who were receiving hydroxyurea compared with those receiving placebo. Because cost savings are likely to increase with age, these data provide additional support for broad use of hydroxyurea treatment in this population. PMID:23999955
Cell cycle progression in irradiated endothelial cells cultured from bovine aorta
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rubin, D.B.; Drab, E.A.; Ward, W.F.
1988-11-01
Logarithmically growing endothelial cells from bovine aortas were exposed to single doses of 0-10 Gy of 60Co gamma rays, and cell cycle phase distribution and progression were examined by flow cytometry and autoradiography. In some experiments, cells were synchronized in the cell cycle with hydroxyurea (1 mM). Cell number in sham-irradiated control cultures doubled in approximately 24 h. Estimated cycle stage times for control cells were 14.4 h for G1 phase, 7.2 h for S phase, and 2.4 h for G2 + M phase. Irradiated cells demonstrated a reduced distribution at the G1/S phase border at 4 h, and anmore » increased distribution in G2 + M phase at 24 h postirradiation. Autoradiographs of irradiated cells after continuous (3H)thymidine labeling indicated a block in G1 phase or at the G1/S-phase border. The duration of the block was dose dependent (2-3 min/cGy). Progression of the endothelial cells through S phase after removal of the hydroxyurea block also was retarded by irradiation, as demonstrated by increased distribution in early S phase and decreased distribution in late S phase. These results indicate that progression of asynchronous cultured bovine aortic endothelial cells through the DNA synthetic cycle is susceptible to radiation inhibition at specific sites in the cycle, resulting in redistribution and partial synchronization of the population. Thus aortic endothelial cells, diploid cells from a normal tissue, resemble many immortal cell types that have been examined in this regard in vitro.« less
Teixeira Neto, Paulo Florentino; Gonçalves, Romélia Pinheiro; Elias, Darcielle Bruna Dias; de Araújo, Cleiton Pinheiro; Magalhães, Hemerson Iury Ferreira
2011-01-01
Background Sickle cell anemia is a hemoglobinopathy caused by a mutation that results in the production of an abnormal hemoglobin molecule, hemoglobin S (Hb S). This is responsible for profound physiological changes, such as the sickling of red blood cells. Several studies have shown that hydroxyurea protects against vaso-occlusive crises. Objective The aim of this study was to evaluate the oxidative stress associated with biochemical parameters in patients with sickle cell anemia treated with hydroxyurea. Methods The study was conducted with 20 male and 25 female patients at the Hospital Universitário Walter Cantídio. The patients were divided into two groups: a study group (n = 12), patients with sickle cell anemia who were receiving hydroxyurea and a control group (n = 33) of sickle cell anemia patients not submitted to hydroxyurea treatment. The biochemical parameters analyzed were ferritin, transferrin, and serum iron. Glutathione was measured in its reduced form to analyze the oxidative state. Results The results showed insignificant increases in the levels of serum iron, transferrin and ferritin in patients treated with hydroxyurea when compared with those who did not take the medication. However, the glutathione levels were significantly higher in patients taking hydroxyurea than in controls. Conclusions These results indicate that hydroxyurea possibly acts as an antioxidant by increasing glutathione levels. PMID:23049297
Chatterjee, Tridip; Chakravarty, Amit; Chakravarty, Sudipa
2018-05-01
The haematological and clinical response to hydroxyurea was estimated in HbE-beta, beta thalassaemia and sickle cell anaemia patients of Eastern India, with variable clinical severity and transfusion requirement to determine whether hydroxyurea can help these patients to maintain their steady haemoglobin level without blood transfusions. Three hundred patients (189 HbE-beta thalassaemia, 95 beta thalassaemia and 16 other haemoglobinopathies including sickle cell anaemia) were selected for hydroxyurea therapy and were followed up for 48-60 months. Results suggest significant response to hydroxyurea therapy in 19 beta and 99 HbE-beta patients in the transfusion-dependent group (GR-I). All of them became transfusion-independent while on hydroxyurea therapy. The majority of responding patients were IVS1-5(G-C) in one of their alleles in HbE-beta cases (83 out of 119). Though IVS1-5(G-C) was found to be the commonest mutation in our selected patients, the mutational background of the patients does not found to have any significant correlation with the response category towards hydroxyurea as per the results observed in our study. But, the drug works pretty well in most of the transfusion-dependent patients, as these patients were withdrawn from regular blood transfusion. At the same time, partial or no response to the drug hydroxyurea was also recorded in our study.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sasaki, H.; Nishimoto, T.
1989-10-01
Caffeine has been reported to induce premature chromosome condensation (PCC) in S-phase cells in the presence of an inhibitor of DNA synthesis. We found that when S-phase cells are treated with caffeine and hydroxyurea after X irradiation, substantially more potentially lethal damage (PLD) is expressed, but the addition of cycloheximide, which inhibits PCC induction in S-phase cells, in the presence of caffeine and hydroxyurea reduces the expression of PLD to the same level as seen with caffeine alone. This can be interpreted to mean that the expression of PLD seen with caffeine in the absence of an inhibitor of DNAmore » synthesis is not associated with chromosome condensation. Evidence that PCC induction in S-phase cells and the influence of caffeine on PLD expression were suppressed by incubation at 40 degrees C of tsBN75 cells with a ts defect in ubiquitin-activating enzyme indicates the involvement of ubiquitin in these two processes. These observations as well as previous findings on ubiquitin suggest to us that caffeine induces changes in DNA-chromatin conformation, which are caused by induction of PCC or ubiquitination of chromosomal protein. Such changes occurring postirradiation would favor expression of PLD.« less
An origin-deficient yeast artificial chromosome triggers a cell cycle checkpoint.
van Brabant, A J; Buchanan, C D; Charboneau, E; Fangman, W L; Brewer, B J
2001-04-01
Checkpoint controls coordinate entry into mitosis with the completion of DNA replication. Depletion of nucleotide precursors by treatment with the drug hydroxyurea triggers such a checkpoint response. However, it is not clear whether the signal for this hydroxyurea-induced checkpoint pathway is the presence of unreplicated DNA, or rather the persistence of single-stranded or damaged DNA. In a yeast artificial chromosome (YAC) we have engineered an approximately 170 kb region lacking efficient replication origins that allows us to explore the specific effects of unreplicated DNA on cell cycle progression. Replication of this YAC extends the length of S phase and causes cells to engage an S/M checkpoint. In the absence of Rad9 the YAC becomes unstable, undergoing deletions within the origin-free region.
Penkert, Rhiannon R; Lavoie, Paul; Tang, Li; Sun, Yilun; Hurwitz, Julia L
2016-01-01
Parvovirus B19 infection causes transient aplastic crisis in sickle cell disease (SCD) due to a temporary interruption in the red blood cell production. Toxicity from hydroxyurea includes anemia and reticulocytopenia, both of which also occur during a transient aplastic crisis event. Hydroxyurea inhibits proliferation of hematopoietic cells and may be immunosuppressive. We postulated that hydroxyurea could exacerbate parvovirus B19-induced aplastic crisis and inhibit the development of specific immune responses in children with SCD. We conducted a retrospective review of parvovirus B19 infection in 330 children with SCD. Altogether there were 120 known cases of aplastic crisis attributed to parvovirus B19 infection, and 12% of children were on hydroxyurea treatment during the episode. We evaluated hematological and immune responses. Children with HbSS or HbSβ0-thalassemia treated with hydroxyurea, when compared with untreated children, required fewer transfusions and had higher Hb concentration nadir during transient aplastic crisis. Duration of hospital stays was no different between hydroxyurea-treated and untreated groups. Children tested within a week following aplastic crisis were positive for parvovirus-specific IgG. Immune responses lasted for the duration of the observation period, up to 13 years after transient aplastic crisis, and there were no repeat aplastic crisis episodes. The frequencies of parvovirus-specific antibodies in all children with SCD increased with age, as expected due to the increased likelihood of a parvovirus exposure, and were comparable to frequencies reported for healthy children. Approximately one-third of children had a positive parvovirus B19-specific IgG test without a documented history of transient aplastic crisis, and 64% of them were treated with hydroxyurea. Hydroxyurea may reduce requirements for blood transfusions and may attenuate symptoms during transient aplastic crisis episodes caused by parvovirus B19 infections. Children with SCD, whether treated or untreated with hydroxyurea, generate sustained and protective parvovirus B19-specific immune responses. PMID:26940953
Hankins, Jane S; Penkert, Rhiannon R; Lavoie, Paul; Tang, Li; Sun, Yilun; Hurwitz, Julia L
2016-04-01
Parvovirus B19 infection causes transient aplastic crisis in sickle cell disease (SCD) due to a temporary interruption in the red blood cell production. Toxicity from hydroxyurea includes anemia and reticulocytopenia, both of which also occur during a transient aplastic crisis event. Hydroxyurea inhibits proliferation of hematopoietic cells and may be immunosuppressive. We postulated that hydroxyurea could exacerbate parvovirus B19-induced aplastic crisis and inhibit the development of specific immune responses in children with SCD. We conducted a retrospective review of parvovirus B19 infection in 330 children with SCD. Altogether there were 120 known cases of aplastic crisis attributed to parvovirus B19 infection, and 12% of children were on hydroxyurea treatment during the episode. We evaluated hematological and immune responses. Children with HbSS or HbSβ(0)-thalassemia treated with hydroxyurea, when compared with untreated children, required fewer transfusions and had higher Hb concentration nadir during transient aplastic crisis. Duration of hospital stays was no different between hydroxyurea-treated and untreated groups. Children tested within a week following aplastic crisis were positive for parvovirus-specific IgG. Immune responses lasted for the duration of the observation period, up to 13 years after transient aplastic crisis, and there were no repeat aplastic crisis episodes. The frequencies of parvovirus-specific antibodies in all children with SCD increased with age, as expected due to the increased likelihood of a parvovirus exposure, and were comparable to frequencies reported for healthy children. Approximately one-third of children had a positive parvovirus B19-specific IgG test without a documented history of transient aplastic crisis, and 64% of them were treated with hydroxyurea. Hydroxyurea may reduce requirements for blood transfusions and may attenuate symptoms during transient aplastic crisis episodes caused by parvovirus B19 infections. Children with SCD, whether treated or untreated with hydroxyurea, generate sustained and protective parvovirus B19-specific immune responses. © 2016 by the Society for Experimental Biology and Medicine.
Shimizu, Takayuki; Mori, Takehiko; Karigane, Daiki; Kikuchi, Taku; Koda, Yuya; Toyama, Takaaki; Nakajima, Hideaki; Okamoto, Shinichiro
2014-01-01
A 62-year-old man with refractory leukemia transformed from myelodysplastic syndrome was placed on hydroxyurea (hydroxycarbamide) at a daily dose of 500 mg. Because of insufficient cytoreductive efficacy, the dose was increased to 1,500 mg five days later. Eight days after the initiation of hydroxyurea, the patient started complaining of chills, fever, and vomiting. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were markedly elevated to 5,098 and 3,880 IU/l from 44 and 59 IU/l in one day, respectively. Tests for hepatitis viruses were all negative. With the discontinuation of hydroxyurea, AST and ALT returned to their former levels within two weeks. A drug-induced lymphocyte stimulation test for hydroxyurea was positive with a stimulating index of 2.0. Hepatic dysfunction has been recognized as one of the side effects of hydroxyurea. However, there have been only a limited number of reports demonstrating drug allergy to have a role in hepatic dysfunction accompanied by fever and gastrointestinal symptoms. The findings of our case strongly suggest that all presentations could be explained by drug allergy. Physicians should be mindful of the potential for acute and severe hepatic dysfunction due to allergic reaction against hydroxyurea.
Blood transfusion versus hydroxyurea in beta-thalassemia in Iran: a cost-effectiveness study.
Ravangard, Ramin; Mirzaei, Zahra; Keshavarz, Khosro; Haghpanah, Sezaneh; Karimi, Mehran
2017-11-21
Thalassemia intermedia is a type of anemia which has several treatments modalities. We aimed to study the cost effectiveness of two treatments, including blood transfusion and hydroxyurea, in patients with beta-thalassemia intermedia in south of Iran referred to a referral center affiliated to Iran, Shiraz University of Medical Sciences in 2015. This was a cost-effectiveness study which was conducted on 122 patients with beta-thalassemia intermedia. The indicator of effectiveness in this study was the reduction of growth disorder (normal BMI). Data analysis was done using SPSS 21, Excel 2010 and Treeage 2011. Finally, the one-way sensitivity analysis was performed to determine the robustness of the results. The average annual costs of blood transfusion and the use of hydroxyurea in 2015 were 20733.27 purchasing power parity (PPP)$ and 7040.29 PPP$, respectively. The effectiveness of blood transfusion was57.4% while in hydroxyurea group was 60.7%. The results showed that the cost effectiveness of using hydroxyurea was more than that of blood transfusion. Therefore, it is recommended that the use of hydroxyurea in the treatment of patients with beta-thalassemia intermedia would become the first priority, and more basic and supplementary insurance coverage for treating such patients using hydroxyurea should be considered.
Widespread Natural Occurrence of Hydroxyurea in Animals.
Fraser, David I; Liu, Kyle T; Reid, Bryan J; Hawkins, Emily; Sevier, Andrew; Pyle, Michelle; Robinson, Jacob W; Ouellette, Pierre H R; Ballantyne, James S
2015-01-01
Here we report the widespread natural occurrence of a known antibiotic and antineoplastic compound, hydroxyurea in animals from many taxonomic groups. Hydroxyurea occurs in all the organisms we have examined including invertebrates (molluscs and crustaceans), fishes from several major groups, amphibians and mammals. The species with highest concentrations was an elasmobranch (sharks, skates and rays), the little skate Leucoraja erinacea with levels up to 250 μM, high enough to have antiviral, antimicrobial and antineoplastic effects based on in vitro studies. Embryos of L. erinacea showed increasing levels of hydroxyurea with development, indicating the capacity for hydroxyurea synthesis. Certain tissues of other organisms (e.g. skin of the frog (64 μM), intestine of lobster (138 μM) gills of the surf clam (100 μM)) had levels high enough to have antiviral effects based on in vitro studies. Hydroxyurea is widely used clinically in the treatment of certain human cancers, sickle cell anemia, psoriasis, myeloproliferative diseases, and has been investigated as a potential treatment of HIV infection and its presence at high levels in tissues of elasmobranchs and other organisms suggests a novel mechanism for fighting disease that may explain the disease resistance of some groups. In light of the known production of nitric oxide from exogenously applied hydroxyurea, endogenous hydoxyurea may play a hitherto unknown role in nitric oxide dynamics.
Widespread Natural Occurrence of Hydroxyurea in Animals
Fraser, David I.; Liu, Kyle T.; Reid, Bryan J.; Hawkins, Emily; Sevier, Andrew; Pyle, Michelle; Robinson, Jacob W.; Ouellette, Pierre H. R.; Ballantyne, James S.
2015-01-01
Here we report the widespread natural occurrence of a known antibiotic and antineoplastic compound, hydroxyurea in animals from many taxonomic groups. Hydroxyurea occurs in all the organisms we have examined including invertebrates (molluscs and crustaceans), fishes from several major groups, amphibians and mammals. The species with highest concentrations was an elasmobranch (sharks, skates and rays), the little skate Leucoraja erinacea with levels up to 250 μM, high enough to have antiviral, antimicrobial and antineoplastic effects based on in vitro studies. Embryos of L. erinacea showed increasing levels of hydroxyurea with development, indicating the capacity for hydroxyurea synthesis. Certain tissues of other organisms (e.g. skin of the frog (64 μM), intestine of lobster (138 μM) gills of the surf clam (100 μM)) had levels high enough to have antiviral effects based on in vitro studies. Hydroxyurea is widely used clinically in the treatment of certain human cancers, sickle cell anemia, psoriasis, myeloproliferative diseases, and has been investigated as a potential treatment of HIV infection and its presence at high levels in tissues of elasmobranchs and other organisms suggests a novel mechanism for fighting disease that may explain the disease resistance of some groups. In light of the known production of nitric oxide from exogenously applied hydroxyurea, endogenous hydoxyurea may play a hitherto unknown role in nitric oxide dynamics. PMID:26600157
[Case of pediatric chronic myeloid leukemia with bilateral visual loss onset].
Hara, Yusuke; Kamura, Yumi; Oikawa, Aki; Shichino, Hiroyuki; Mugishima, Hideo; Goto, Hiroshi
2010-05-01
Chronic myeloid leukemia (CML) during childhood is rare, and only been a few cases showed visual disturbances as an initial symptom. We report a pediatric CML case diagnosed by bilateral visual loss. An 11-year-old boy complained of visual loss in both eyes. His best corrected visual acuity was 0.5 in the right eye and 0.2 in the left. Fundus examination showed disc swelling, dilated and tortuous retinal veins and multiple elevated retinal lesions with hemorrhages of various size from one-forth to four disc diameters in both eyes. He was diagnosed as having CML by leucocytosis and systematic work-up including Philadelphia chromosome-positive, BCR-ABL kinase domain in peripheral blood and bone marrow. The ocular findings improved after treatment with hydroxyurea, leukocytaphresis and imatinib. His best corrected visual acuity improved to 0.7 in both eyes. Recent leukemia therapy including imatinib is effective not only for ocular lesions but also to induce hematological remission in childhood CML.
Hydroxyurea Use in Young Children With Sickle Cell Anemia in New York State.
Anders, David G; Tang, Fei; Ledneva, Tatania; Caggana, Michele; Green, Nancy S; Wang, Ying; Sturman, Lawrence S
2016-07-01
This study examined hydroxyurea usage in young children with sickle cell anemia within New York State (NYS). The cohort was 273 children with sickle cell anemia born in NYS in 2006-2009 and enrolled essentially continuously in Medicaid for the first 4 years of life. Medicaid data were used to examine hydroxyurea usage in this group by age at first prescription fill, persistence, region, treatment institution, and year. Log-binomial regression models were used to estimate the likelihood of receiving hydroxyurea treatment. Data from birth through 2014 for all members of the study group were assembled and analyzed in 2015. About 25% of the cohort had at least one filled hydroxyurea prescription by their fifth birthday, and nearly 40% by the end of the study period. The mean proportion of days covered for the first year of therapy was 56.3%. Adherence was also assessed by calculating medication possession ratios for individual treatment periods. Slightly more than one third of treated children showed 80% coverage by these measures. There was a consistent, but not statistically significant, trend toward younger age at first fill. Significant regional and treatment center differences in initiation of hydroxyurea use, but not in persistence after initiation, were noted among NYS centers. Subsequent to clinical studies demonstrating safety, current NYS-wide use of hydroxyurea in young children with sickle cell anemia appears to be widespread and increasing. However, practice differences between treatment centers and inadequate adherence may limit the full disease-modifying effects of hydroxyurea. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.
Hydroxyurea-Lactose Interaction Study: In Silico and In Vitro Evaluation.
Bachchhao, Kunal B; Patil, R R; Patil, C R; Patil, Dipak D
2017-11-01
The Maillard reaction between hydroxyurea (a primary amine-containing drug) and lactose (used as an excipient) was explored. The adduct of these compounds was synthesized by heating hydroxyurea with lactose monohydrate at 60 °C in borate buffer (pH 9.2) for 12 h. Synthesis of the adduct was confirmed using UV-visible spectroscopy and Fourier transform infrared, differential scanning calorimetry, high-pressure liquid chromatography, and liquid chromatography-mass spectrometry studies. An in silico investigation of how the adduct formation affected the interactions of hydroxyurea with its biological target oxyhemoglobin, to which it binds to generate nitric oxide and regulates fetal hemoglobin synthesis, was carried out. The in silico evaluations were complemented by an in vitro assay of the anti-sickling activity. Co-incubation of hydroxyurea with deoxygenated blood samples reduced the percentage of sickled cells from 38% to 12 ± 1.6%, whereas the percentage of sickled cells in samples treated with the adduct was 17 ± 1.2%. This indicated loss of anti-sickling activity in the case of the adduct. This study confirmed that hydroxyurea can participate in a Maillard reaction if lactose is used as a diluent. Although an extended study at environmentally feasible temperatures was not carried out in the present investigation, the partial loss of the anti-sickling activity of hydroxyurea was investigated along with the in silico drug-target interactions. The results indicated that the use of lactose in hydroxyurea formulations needs urgent reconsideration and that lactose must be replaced by other diluents that do not form Maillard adducts.
Kim, Kyungho; Li, Jing; Barazia, Andrew; Tseng, Alan; Youn, Seock-Won; Abbadessa, Giovanni; Yu, Yi; Schwartz, Brian; Andrews, Robert K.; Gordeuk, Victor R.; Cho, Jaehyung
2017-01-01
Previous studies identified the Ser/Thr protein kinase, AKT, as a therapeutic target in thrombo-inflammatory diseases. Here we report that specific inhibition of AKT with ARQ 092, an orally-available AKT inhibitor currently in phase Ib clinical trials as an anti-cancer drug, attenuates the adhesive function of neutrophils and platelets from sickle cell disease patients in vitro and cell-cell interactions in a mouse model of sickle cell disease. Studies using neutrophils and platelets isolated from sickle cell disease patients revealed that treatment with 50–500 nM ARQ 092 significantly blocks αMβ2 integrin function in neutrophils and reduces P-selectin exposure and glycoprotein Ib/IX/V-mediated agglutination in platelets. Treatment of isolated platelets and neutrophils with ARQ 092 inhibited heterotypic cell-cell aggregation under shear conditions. Intravital microscopic studies demonstrated that short-term oral administration of ARQ 092 or hydroxyurea, a major therapy for sickle cell disease, diminishes heterotypic cell-cell interactions in venules of sickle cell disease mice challenged with tumor necrosis factor-α. Co-administration of hydroxyurea and ARQ 092 further reduced the adhesive function of neutrophils in venules and neutrophil transmigration into alveoli, inhibited expression of E-selectin and intercellular adhesion molecule-1 in cremaster vessels, and improved survival in these mice. Ex vivo studies in sickle cell disease mice suggested that co-administration of hydroxyurea and ARQ 092 efficiently blocks neutrophil and platelet activation and that the beneficial effect of hydroxyurea results from nitric oxide production. Our results provide important evidence that ARQ 092 could be a novel drug for the prevention and treatment of acute vaso-occlusive complications in patients with sickle cell disease. PMID:27758820
Verner, Emma; Forsyth, Cecily; Grigg, Andrew
2014-05-01
Abstract Cyclical thrombocytosis, acquired von Willebrand syndrome, aggressive non-melanoma skin cancers and other hydroxyurea complications have been reported in Philadelphia-negative myeloproliferative neoplasms (MPNs), but their incidence and clinical consequences have not been defined in a large cohort of patients. We conducted a retrospective analysis of 188 consecutive patients with MPNs specifically addressing the incidence of these complications. Cyclical thrombocytosis was documented in 29 patients (15%), the majority of whom were receiving hydroxyurea. Acquired von Willebrand syndrome was identified in 17 of the 84 screened patients (20%), but was not associated with any major bleeding complications. Non-melanoma skin cancers were reported in 51 patients (27%). Hydroxyurea-related fever occurred in nine of 149 patients (6%) who received hydroxyurea. Seventy-three patients (39%) experienced a total of 98 major thrombotic events, with the majority of these occurring prior to or within 3 months of the diagnosis. Cyclical thrombocytosis, acquired von Willebrand syndrome, aggressive non-melanoma skin cancers and other hydroxyurea-related complications are not infrequent in MPNs and have important clinical consequences for management.
Osemwota, Osamuede; Uhlemann, John; Rubin, Adam
2017-08-01
Twenty-nail transverse melanonychia from hydroxyurea is a rare phenomenon, only reported four times previously. Here we describe a 51-year-old female who presented with 20-nail transverse melanonychia 3 months after initiating hydroxyurea therapy. Transverse melanonychia is a benign process but can cause patients significant distress, and thus is an entity with which dermatologists should recognize. We then review the cutaneous manifestations, differential diagnosis, and clinical considerations when evaluating patients with transverse melanonychia from hydroxyurea or other causes.
J Drugs Dermatol. 2017;16(8):814-815.
.Iman, Maryam; Khansefid, Zeynab; Davood, Asghar
2016-01-01
Ribonucleotide Reductase (RNR) is an important anticancer chemotherapy target. It has main key role in DNA synthesis and cell growth. Therefore several RNR inhibitors, such as hydroxyurea, have entered the clinical trials. Based on our proposed mechanism, radical site of RNR protein reacts with hydroxyurea in which hydroxyurea is converted into its oxidized form compound III, and whereby the tyrosyl radical is converted into a normal tyrosine residue. In this study, docking and molecular dynamics simulations were used for proposed molecular mechanism of hydroxyurea in RNR inhibition as anticancer agent. The binding affinity of hydroxyurea and compound III to RNR was studied by docking method. The docking study was performed for the crystal structure of human RNR with the radical scavenger Hydroxyurea and its oxidized form to inhibit the human RNR. hydroxyurea and compound III bind at the active site with Tyr-176, which are essential for free radical formation. This helps to understand the functional aspects and also aids in the development of novel inhibitors for the human RNR2. To confirm the binding mode of inhibitors, the molecular dynamics (MD) simulations were performed using GROMACS 4.5.5, based upon the docked conformation of inhibitors. Both of the studied compounds stayed in the active site. The results of MD simulations confirmed the binding mode of ligands, accuracy of docking and the reliability of active conformations which were obtained by AutoDock. MD studies confirm our proposed mechanism in which compound III reacts with the active site residues specially Tyr-176, and inhibits the radical generation and subsequently inhibits the RNR enzyme.
Wang, Winfred C; Ware, Russell E; Miller, Scott T; Iyer, Rathi V; Casella, James F; Minniti, Caterina P; Rana, Sohail; Thornburg, Courtney D; Rogers, Zora R; Kalpatthi, Ram V; Barredo, Julio C; Brown, R Clark; Sarnaik, Sharada A; Howard, Thomas H; Wynn, Lynn W; Kutlar, Abdullah; Armstrong, F Daniel; Files, Beatrice A; Goldsmith, Jonathan C; Waclawiw, Myron A; Huang, Xiangke; Thompson, Bruce W
2011-01-01
Background Sickle cell anaemia (SCA) is associated with significant morbidity from acute complications and organ dysfunction beginning in the first year of life. In the first multicenter randomised double-blinded trial in very young children with SCA, the impact of hydroxyurea (hydroxycarbamide) therapy on organ dysfunction, clinical complications, and laboratory findings, and its toxicity, were examined. Methods Eligible subjects had HbSS or Sβ0thalassaemia, were age 9–18 months at randomisation, and were not selected for clinical severity. Subjects received liquid hydroxyurea, 20 mg/kg/day, or placebo for two years. Primary study endpoints were splenic function (qualitative uptake on 99Tc spleen scan) and renal function (glomerular filtration rate by 99mTc-DTPA clearance). Additional evaluations included: blood counts, HbF, chemistry profiles, spleen function biomarkers, urine osmolality, neurodevelopment, transcranial Doppler ultrasonography, growth, and mutagenicity. Study visits occurred every two to four weeks. Findings Ninety-six subjects received hydroxyurea and 97 placebo; 86% completed the study. Significant differences were not seen for the primary endpoints, but suggestive benefit was noted in quantitative measures of spleen function. Hydroxyurea significantly decreased pain and dactylitis with trends for decreased acute chest syndrome, hospitalisation and transfusion. Hydroxyurea increased haemoglobin and HbF and decreased WBC count. Toxicity was limited to mild-moderate neutropaenia. Interpretation Although hydroxyurea treatment did not reduce splenic and renal dysfunction assessed by primary endpoint measures, it resulted in major clinical benefit because of diminished acute complications, favorable haematologic results, and a lack of unexpected toxicities. Based on the safety and efficacy data from this trial, hydroxyurea can now be considered for all very young children with SCA. PMID:21571150
HYDROXYUREA TREATMENT DECREASES GLOMERULAR HYPERFILTRATION IN CHILDREN WITH SICKLE CELL ANEMIA
Aygun, Banu; Mortier, Nicole A.; Smeltzer, Matthew P.; Shulkin, Barry L.; Hankins, Jane S.; Ware, Russell E.
2015-01-01
Background Glomerular hyperfiltration and microalbuminuria/proteinuria are early manifestations of sickle nephropathy. The effects of hydroxyurea therapy on these renal manifestations of sickle cell anemia (SCA) are not well defined. Objective To investigate the effects of hydroxyurea on glomerular filtration rate (GFR) measured by 99mTc-DTPA clearance, and on microalbuminuria/proteinuria in children with SCA. Study Design Hydroxyurea Study of Long-Term Effects (HUSTLE) is a prospective study (NCT00305175) with the goal of describing the long-term cellular, molecular, and clinical effects of hydroxyurea therapy in SCA. Glomerular filtration rate, urine microalbumin, and serum cystatin C were measured before initiating hydroxyurea therapy and then repeated after 3 years. Baseline and Year 3 values for HUSTLE subjects were compared using the Wilcoxon Signed Rank test. Associations between continuous variables were evaluated using Spearman correlation coefficient. Results Twenty-three children with SCA (median age 7.5 years, range 2.5–14.0 years) received hydroxyurea at maximum tolerated dose (MTD, 24.4 ± 4.5 mg/kg/day, range 15.3–30.6 mg/kg/day). After three years of treatment, GFR measured by 99mTc-DTPA decreased significantly from 167 ± 46 mL/min/1.73m2 to 145 ± 27 mL/min/1.73m2 (p=0.016). This decrease in GFR was significantly associated with increase in fetal hemoglobin (p= 0.042) and decrease in lactate dehydrogenase levels (p=0.035). Urine microalbumin and cystatin C levels did not change significantly. Conclusions Hydroxyurea at MTD is associated with a decrease in hyperfiltration in young children with SCA. PMID:23255310
Patel, Siris; Purohit, Prasanta; Mashon, Ranjeet Singh; Dehury, Snehadhini; Meher, Satyabrata; Sahoo, Sulia; Dash, Subhransu Sekhar; Das, Kishalaya; Das, Padmalaya; Patel, Dilip Kumar
2014-08-01
Although hydroxyurea is the only effective agent for the treatment of sickle cell disease, published experience with this drug is limited to treatment of homozygous sickle cell anemia and HbS/β thalassemia. The role of hydroxyurea in the treatment of patients with HbSD-Punjab, a rare hemoglobinopathy with phenotypic expression similar to that of sickle cell anemia is unknown. Over a period of 10 years, we followed 42 patients with HbSD-Punjab, of which 20 presented with severe clinical manifestations (≥3 episodes of VOC and/or ≥2 units of blood transfusion in the previous 12 months). These 20 patients were enrolled for treatment with hydroxyurea at a dose of 10 mg/kg/day and followed prospectively for a period of 24 months. The frequency of VOC decreased significantly and none of them required blood transfusion while receiving hydroxyurea. The HbF, total hemoglobin, MCV, MCH, and MCHC levels increased significantly, whereas HbS, WBC, platelet count, total serum bilirubin, and LDH levels decreased significantly in all the patients. No short-term drug toxicity was observed. This study describes the use of hydroxyurea therapy in patients with HbSD-Punjab. Low dose hydroxyurea (10 mg/kg/day) was found to be effective in reducing the clinical severity in patients with HbSD-Punjab without any short-term toxicity. In view of easy affordability amongst poor patients, widespread acceptability by patients and doctors, the need of infrequent monitoring and its potential effectiveness, low dose hydroxyurea is suitable for treatment of patients with HbSD-Punjab. © 2014 Wiley Periodicals, Inc.
El Husseini, Nazem; Schlisser, Ava E.; Hales, Barbara F.
2016-01-01
Hydroxyurea, an anticancer agent and potent teratogen, induces oxidative stress and activates a DNA damage response pathway in the gestation day (GD) 9 mouse embryo. To delineate the stress response pathways activated by this drug, we investigated the effect of hydroxyurea exposure on the transcriptome of GD 9 embryos. Timed pregnant CD-1 mice were treated with saline or hydroxyurea (400 mg/kg or 600 mg/kg) on GD 9; embryonic gene and protein expression were examined 3 h later. Microarray analysis revealed that the expression of 1346 probe sets changed significantly in embryos exposed to hydroxyurea compared with controls; the P53 signaling pathway was highly affected. In addition, P53 related family members, P63 and P73, were predicted to be activated and had common and unique downstream targets. Western blot analysis revealed that active phospho-P53 was significantly increased in drug-exposed embryos; confocal microscopy showed that the translocation of phospho-P53 to the nucleus was widespread in the embryo. Furthermore, qRT-PCR showed that the expression of P53-regulated genes (Cdkn1A, Fas, and Trp53inp1) was significantly upregulated in hydroxyurea-exposed embryos; the concentration of the redox sensitive P53INP1 protein was also increased in a hydroxyurea dose-dependent fashion. Thus, hydroxyurea elicits a significant effect on the transcriptome of the organogenesis stage murine embryo, activating several key developmental signaling pathways related to DNA damage and oxidative stress. We propose that the P53 pathway plays a central role in the embryonic stress response and the developmental outcome after teratogen exposure. PMID:27208086
Lovick, Jennifer K.; Hartenstein, Volker
2015-01-01
The Drosophila brain is comprised of neurons formed by approximately 100 lineages, each of which is derived from a stereotyped, asymmetrically dividing neuroblast. Lineages serve as structural and developmental units of Drosophila brain anatomy and reconstruction of lineage projection patterns represents a suitable map of Drosophila brain circuitry at the level of neuron populations (“macro-circuitry”). Two phases of neuroblast proliferation, the first in the embryo and the second during the larval phase (following a period of mitotic quiescence), produce primary and secondary lineages, respectively. Using temporally controlled pulses of hydroxyurea (HU) to ablate neuroblasts and their corresponding secondary lineages during the larval phase, we analyzed the effect on development of primary and secondary lineages in the late larval and adult brain. Our findings indicate that timing of neuroblast re-activation is highly stereotyped, allowing us to establish “birth dates” for all secondary lineages. Furthermore, our results demonstrate that, whereas the trajectory and projection pattern of primary and secondary lineages is established in a largely independent manner, the final branching pattern of secondary neurons is dependent upon the presence of appropriate neuronal targets. Taken together, our data provide new insights into the degree of neuronal plasticity during Drosophila brain development. PMID:25773365
Hydroxyurea therapy requires HbF induction for clinical benefit in a sickle cell mouse model
Lebensburger, Jeffrey D.; Pestina, Tamara I.; Ware, Russell E.; Boyd, Kelli L.; Persons, Derek A.
2010-01-01
Hydroxyurea has proven clinical efficacy in patients with sickle cell disease. Potential mechanisms for the beneficial effects include fetal hemoglobin induction and the reduction of cell adhesive properties, inflammation and hypercoagulability. Using a murine model of sickle cell disease in which fetal hemoglobin induction does not occur, we evaluated whether hydroxyurea administration would still yield improvements in hematologic parameters and reduce end-organ damage. Animals given a maximally tolerated dose of hydroxyurea that resulted in significant reductions in the neutrophil and platelet counts showed no improvement in hemolytic anemia and end-organ damage compared to control mice. In contrast, animals having high levels of fetal hemoglobin due to gene transfer with a γ-globin lentiviral vector showed correction of anemia and organ damage. These data suggest that induction of fetal hemoglobin by hydroxyurea is an essential mechanism for its clinical benefits. PMID:20378564
Survival and mortality among users and non-users of hydroxyurea with sickle cell disease
de Araujo, Olinda Maria Rodrigues; Ivo, Maria Lúcia; Ferreira, Marcos Antonio; Pontes, Elenir Rose Jardim Cury; Bispo, Ieda Maria Gonçalves Pacce; de Oliveira, Eveny Cristine Luna
2015-01-01
OBJECTIVE: to estimate survival, mortality and cause of death among users or not of hydroxyurea with sickle cell disease. METHOD: cohort study with retrospective data collection, from 1980 to 2010 of patients receiving inpatient treatment in two Brazilian public hospitals. The survival probability was determined using the Kaplan-Meier estimator, survival calculations (SPSS version 10.0), comparison between survival curves, using the log rank method. The level of significance was p=0.05. RESULTS: of 63 patients, 87% had sickle cell anemia, with 39 using hydroxyurea, with a mean time of use of the drug of 20.0±10.0 years and a mean dose of 17.37±5.4 to 20.94±7.2 mg/kg/day, raising the fetal hemoglobin. In the comparison between those using hydroxyurea and those not, the survival curve was greater among the users (p=0.014). A total of 10 deaths occurred, with a mean age of 28.1 years old, and with Acute Respiratory Failure as the main cause. CONCLUSION: the survival curve is greater among the users of hydroxyurea. The results indicate the importance of the nurse incorporating therapeutic advances of hydroxyurea in her care actions. PMID:25806633
Hydroxyurea could be a good clinically relevant iron chelator.
Italia, Khushnooma; Colah, Roshan; Ghosh, Kanjaksha
2013-01-01
Our previous study showed a reduction in serum ferritin of β-thalassemia patients on hydroxyurea therapy. Here we aimed to evaluate the efficacy of hydroxyurea alone and in combination with most widely used iron chelators like deferiprone and deferasirox for reducing iron from experimentally iron overloaded mice. 70 BALB/c mice received intraperitonial injections of iron-sucrose. The mice were then divided into 8 groups and were orally given hydroxyurea, deferiprone or deferasirox alone and their combinations for 4 months. CBC, serum-ferritin, TBARS, sTfr and hepcidin were evaluated before and after iron overload and subsequently after 4 months of drug therapy. All animals were then killed. Iron staining of the heart and liver tissue was done using Perl's Prussian Blue stain. Dry weight of iron in the heart and liver was determined by atomic absorption spectrometry. Increased serum-ferritin, TBARS, hepcidin and dry weight of iron in the liver and heart showed a significant reduction in groups treated with iron chelators with maximum reduction in the group treated with a combination of deferiprone, deferasirox and hydroxyurea. Thus hydroxyurea proves its role in reducing iron from iron overloaded mice. The iron chelating effect of these drugs can also be increased if given in combination.
Survival and mortality among users and non-users of hydroxyurea with sickle cell disease.
de Araujo, Olinda Maria Rodrigues; Ivo, Maria Lúcia; Ferreira Júnior, Marcos Antonio; Pontes, Elenir Rose Jardim Cury; Bispo, Ieda Maria Gonçalves Pacce; de Oliveira, Eveny Cristine Luna
2015-01-01
to estimate survival, mortality and cause of death among users or not of hydroxyurea with sickle cell disease. cohort study with retrospective data collection, from 1980 to 2010 of patients receiving inpatient treatment in two Brazilian public hospitals. The survival probability was determined using the Kaplan-Meier estimator, survival calculations (SPSS version 10.0), comparison between survival curves, using the log rank method. The level of significance was p=0.05. of 63 patients, 87% had sickle cell anemia, with 39 using hydroxyurea, with a mean time of use of the drug of 20.0±10.0 years and a mean dose of 17.37±5.4 to 20.94±7.2 mg/kg/day, raising the fetal hemoglobin. In the comparison between those using hydroxyurea and those not, the survival curve was greater among the users (p=0.014). A total of 10 deaths occurred, with a mean age of 28.1 years old, and with Acute Respiratory Failure as the main cause. the survival curve is greater among the users of hydroxyurea. The results indicate the importance of the nurse incorporating therapeutic advances of hydroxyurea in her care actions.
Mulaku, Mercy; Opiyo, Newton; Karumbi, Jamlick; Kitonyi, Grace; Thoithi, Grace; English, Mike
2013-11-01
Hydroxyurea is widely used in high-income countries for the management of sickle cell disease (SCD) in children. In Kenyan clinical guidelines, hydroxyurea is only recommended for adults with SCD. Yet many deaths from SCD occur in early childhood, deaths that might be prevented by an effective, disease modifying intervention. The aim of this review was to summarise the available evidence on the efficacy, effectiveness and safety of hydroxyurea in the management of SCD in children below 5 years of age to support guideline development in Kenya. We undertook a systematic review and used the Grading of Recommendations Assessment, Development and Evaluation system to appraise the quality of identified evidence. Overall, available evidence from 1 systematic review (n=26 studies), 2 randomised controlled trials (n=354 children), 14 observational studies and 2 National Institute of Health reports suggest that hydroxyurea may be associated with improved fetal haemoglobin levels, reduced rates of hospitalisation, reduced episodes of acute chest syndrome and decreased frequency of pain events in children with SCD. However, it is associated with adverse events (eg, neutropenia) when high to maximum tolerated doses are used. Evidence is lacking on whether hydroxyurea improves survival if given to young children. Majority of the included studies were of low quality and mainly from high-income countries. Overall, available limited evidence suggests that hydroxyurea may improve morbidity and haematological outcomes in SCD in children aged below 5 years and appears safe in settings able to provide consistent haematological monitoring.
Ruxolitinib for the Treatment of Patients With Polycythemia Vera
Kiladjian, Jean-Jacques; Winton, Elliott F.; Talpaz, Moshe; Verstovsek, Srdan
2015-01-01
SUMMARY Polycythemia vera (PV) is a hematopoietic proliferative disorder associated with Janus-associated kinase (JAK)/signal transducer and activator of transcription (STAT) pathway dysregulation resulting in erythrocytosis and, possibly, leukocytosis and thrombocytosis. Patients diagnosed with PV experience a broad range of symptoms associated with a reduced quality of life, often develop splenomegaly, and have an increased risk of death compared to age-matched subjects without PV. Current treatment options, notably hydroxyurea, help with disease management; however, insufficient efficacy or progressive resistance occurs in some patients, highlighting the need for new treatment options. Ruxolitinib is an oral JAK1/JAK2 inhibitor that has been evaluated in phase 2 and 3 clinical trials in patients with PV who are intolerant of or resistant to hydroxyurea. In this setting, ruxolitinib treatment has demonstrated normalization of blood cell counts, reduction in splenomegaly, and improvements in PV-related symptom burden. PMID:25980454
Fitzhugh, Courtney D; Hsieh, Matthew M; Allen, Darlene; Coles, Wynona A; Seamon, Cassie; Ring, Michael; Zhao, Xiongce; Minniti, Caterina P; Rodgers, Griffin P; Schechter, Alan N; Tisdale, John F; Taylor, James G
2015-01-01
Adults with sickle cell anemia (HbSS) are inconsistently treated with hydroxyurea. We retrospectively evaluated the effects of elevating fetal hemoglobin with hydroxyurea on organ damage and survival in patients enrolled in our screening study between 2001 and 2010. An electronic medical record facilitated development of a database for comparison of study parameters based on hydroxyurea exposure and dose. This study is registered with ClinicalTrials.gov, number NCT00011648. Three hundred eighty-three adults with homozygous sickle cell disease were analyzed with 59 deaths during study follow-up. Cox regression analysis revealed deceased subjects had more hepatic dysfunction (elevated alkaline phosphatase, Hazard Ratio = 1.005, 95% CI 1.003-1.006, p<0.0.0001), kidney dysfunction (elevated creatinine, Hazard Ratio = 1.13, 95% CI 1.00-1.27, p = 0.043), and cardiopulmonary dysfunction (elevated tricuspid jet velocity on echocardiogram, Hazard Ratio = 2.22, 1.23-4.02, p = 0.0082). Sixty-six percent of subjects were treated with hydroxyurea, although only 66% of those received a dose within the recommended therapeutic range. Hydroxyurea use was associated with improved survival (Hazard Ratio = 0.58, 95% CI 0.34-0.97, p = 0.040). This effect was most pronounced in those taking the recommended dose of 15-35 mg/kg/day (Hazard Ratio 0.36, 95% CI 0.17-0.73, p = 0.0050). Hydroxyurea use was not associated with changes in organ function over time. Further, subjects with higher fetal hemoglobin responses to hydroxyurea were more likely to survive (p = 0.0004). While alkaline phosphatase was lowest in patients with the best fetal hemoglobin response (95.4 versus 123.6, p = 0.0065 and 96.1 versus 113.6U/L, p = 0.041 at first and last visits, respectively), other markers of organ damage were not consistently improved over time in patients with the highest fetal hemoglobin levels. Our data suggest that adults should be treated with the maximum tolerated hydroxyurea dose, ideally before organ damage occurs. Prospective studies are indicated to validate these findings.
Fitzhugh, Courtney D.; Hsieh, Matthew M.; Allen, Darlene; Coles, Wynona A.; Seamon, Cassie; Ring, Michael; Zhao, Xiongce; Minniti, Caterina P.; Rodgers, Griffin P.; Schechter, Alan N.; Tisdale, John F.; Taylor, James G.
2015-01-01
Background Adults with sickle cell anemia (HbSS) are inconsistently treated with hydroxyurea. Objectives We retrospectively evaluated the effects of elevating fetal hemoglobin with hydroxyurea on organ damage and survival in patients enrolled in our screening study between 2001 and 2010. Methods An electronic medical record facilitated development of a database for comparison of study parameters based on hydroxyurea exposure and dose. This study is registered with ClinicalTrials.gov, number NCT00011648. Results Three hundred eighty-three adults with homozygous sickle cell disease were analyzed with 59 deaths during study follow-up. Cox regression analysis revealed deceased subjects had more hepatic dysfunction (elevated alkaline phosphatase, Hazard Ratio = 1.005, 95% CI 1.003–1.006, p<0.0.0001), kidney dysfunction (elevated creatinine, Hazard Ratio = 1.13, 95% CI 1.00–1.27, p = 0.043), and cardiopulmonary dysfunction (elevated tricuspid jet velocity on echocardiogram, Hazard Ratio = 2.22, 1.23–4.02, p = 0.0082). Sixty-six percent of subjects were treated with hydroxyurea, although only 66% of those received a dose within the recommended therapeutic range. Hydroxyurea use was associated with improved survival (Hazard Ratio = 0.58, 95% CI 0.34–0.97, p = 0.040). This effect was most pronounced in those taking the recommended dose of 15–35 mg/kg/day (Hazard Ratio 0.36, 95% CI 0.17–0.73, p = 0.0050). Hydroxyurea use was not associated with changes in organ function over time. Further, subjects with higher fetal hemoglobin responses to hydroxyurea were more likely to survive (p = 0.0004). While alkaline phosphatase was lowest in patients with the best fetal hemoglobin response (95.4 versus 123.6, p = 0.0065 and 96.1 versus 113.6U/L, p = 0.041 at first and last visits, respectively), other markers of organ damage were not consistently improved over time in patients with the highest fetal hemoglobin levels. Conclusions Our data suggest that adults should be treated with the maximum tolerated hydroxyurea dose, ideally before organ damage occurs. Prospective studies are indicated to validate these findings. PMID:26576059
Cutaneous ulcers associated with hydroxyurea therapy.
Quattrone, Filippo; Dini, Valentina; Barbanera, Sabrina; Zerbinati, Nicola; Romanelli, Marco
2013-11-01
Hydroxyurea is an antitumoral drug mainly used in the treatment of Philadelphia chromosome-negative myeloproliferative syndromes and sickle-cell disease. Ulcers represent a rare but severe long-term adverse effect of hydroxyurea therapy. Hydroxyurea-induced ulcers are often multiple and bilateral, typically developing in the perimalleolar region, although any cutaneous district is potentially affected. They generally look small, well-defined, shallow with an adherent, yellow, fibrinous necrotic base. A constant finding is also an extremely intense, treatment-resistant pain accompanying these ulcerations. Withdrawal of the drug generally leads to spontaneous healing of these lesions. Care providers tend to show insufficient awareness of this highly debilitating cutaneous side effect, and late or missed diagnoses are frequent. Instead, regular dermatologic screening should be performed on hydroxyurea-treated patients. This article will present a comprehensive review of indexed case reports and clinical studies, followed by a discussion about treatment options aiming at increasing knowledge about this specific topic. Copyright © 2013 Tissue Viability Society. Published by Elsevier Ltd. All rights reserved.
Maintaining Genome Stability: The Role of Helicases and Deaminases
2006-07-01
functional for replication. Then, we screened the surviving transformants for sensitivity to hydroxyurea . Our first screen was conducted under conditions...that are lethal for checkpoint mutants such as ∆rad3. We did not observe any hydroxyurea -sensitive MCM clones. However, following the old genetics...this kinase. In particular, we observe that an mcm4ts mutant blocked in hydroxyurea , and then released to restrictive temperature, is competent to
Maintaining Genome Stability: The Role of Helicases and Deaminases
2007-07-01
transformants for sensitivity to hydroxyurea . Our first screen was conducted under conditions that are lethal for checkpoint mutants such as ∆rad3...We did not observe any hydroxyurea -sensitive MCM clones. However, following the old genetics adage “absence of evidence is not evidence of... hydroxyurea , and then released to restrictive temperature, is competent to complete replication and go on to divide. In contrast, this mutant shifted
The influence of hydroxyurea on oxidative stress in sickle cell anemia
Torres, Lidiane de Souza; da Silva, Danilo Grünig Humberto; Belini Junior, Edis; de Almeida, Eduardo Alves; Lobo, Clarisse Lopes de Castro; Cançado, Rodolfo Delfini; Ruiz, Milton Artur; Bonini-Domingos, Claudia Regina
2012-01-01
Objective The oxidative stress in 20 sickle cell anemia patients taking hydroxyurea and 13 sickle cell anemia patients who did not take hydroxyurea was compared with a control group of 96 individuals without any hemoglobinopathy. Methods Oxidative stress was assessed by thiobarbituric acid reactive species production, the Trolox-equivalent antioxidant capacity and plasma glutathione levels. Results Thiobarbituric acid reactive species values were higher in patients without specific medication, followed by patients taking hydroxyurea and the Control Group (p < 0.0001). The antioxidant capacity was higher in patients taking hydroxyurea and lower in the Control Group (p = 0.0002 for Trolox-equivalent antioxidant capacity and p < 0.0292 for plasma glutathione). Thiobarbituric acid reactive species levels were correlated with higher hemoglobin S levels (r = 0.55; p = 0.0040) and lower hemoglobin F concentrations(r = -0.52; p = 0.0067). On the other hand, plasma glutathione levels were negatively correlated with hemoglobin S levels (r = -0.49; p = 0.0111) and positively associated with hemoglobin F values (r = 0.56; p = 0.0031). Conclusion Sickle cell anemia patients have high oxidative stress and, conversely, increased antioxidant activity. The increase in hemoglobin F levels provided by hydroxyurea and its antioxidant action may explain the reduction in lipid peroxidation and increased antioxidant defenses in these individuals. PMID:23323065
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liebelt, E.L.; Balk, S.J.; Faber, W.
The National Toxicology Program (NTP) and the National Institute of Environmental Health Sciences (NIEHS) established the NTP Center for the Evaluation of Risks to Human Reproduction (CERHR) in June 1998. The purpose of CERHR is to provide timely, unbiased, scientifically sound evaluations of human and experimental evidence for adverse effects on reproduction and development caused by agents to which humans may be exposed. Hydroxyurea was selected for evaluation by a CERHR expert panel because of (1) its increasing use in the treatment of sickle cell disease in children and adults, (2) knowledge that it inhibits DNA synthesis and is cytotoxic,more » and (3) published evidence of its reproductive and developmental toxicity in rodents. Hydroxyurea is FDA-approved for reducing the frequency of painful crises and the need for blood transfusions in adults with sickle cell anemia who experience recurrent moderate-to-severe crises. Hydroxyurea is used in the treatment of cancer, sickle cell disease, and thalassemia. It is the only treatment for sickle cell disease aside from blood transfusion used in children. Hydroxyurea may be used in the treatment of children and adults with sickle cell disease for an extended period of time or for repeated cycles of therapy. Treatment with hydroxyurea may be associated with cytotoxic and myelosuppressive effects, and hydroxyurea is mutagenic.« less
Patients with sickle cell disease taking hydroxyurea in the Hemocentro Regional de Montes Claros
Santos, Fernanda Kelle de Souza; Maia, Caroline Nogueira
2011-01-01
Background The development of therapies for sickle cell disease has received special attention, particularly those that reduce the polymerization of hemoglobin S. Hydroxyurea is a commonly used medication because it has the ability to raise levels of fetal hemoglobin, decrease the frequency of vaso-occlusive episodes and thus improve the clinical course of sickle cell disease patients. Objective To study hematological data and the clinical profile of sickle cell disease patients taking hydroxyurea in a regional blood center. Methods From the charts of 20 patients with sickle cell anemia, the clinical outcomes and a number of hematological variables were analyzed before and during treatment with hydroxyurea. Results The patients' ages ranged from 6 to 41 years old, most were dark skinned and there was a predominance of women. The main symptom that defined whether patients were prescribed hydroxyurea was painful crises followed by hospitalizations. During treatment with hydroxyurea there were significant increases in hemoglobin, fetal hemoglobin, mean corpuscular volume and mean corpuscular hemoglobin. The reticulocyte and white blood cell counts dropped significantly with treatment. A positive correlation was found between fetal hemoglobin and mean corpuscular volume before and during treatment. Additionally, a correlation was found between the white blood cell and reticulocyte counts before treatment with hydroxyurea. Conclusion Most patients showed improvements with treatment as demonstrated by increases in hemoglobin, fetal hemoglobin and mean corpuscular volume, as well as by reductions in the reticulocyte and white blood cell counts. Clinically, more than 50% of patients had a significant reduction of events. PMID:23284256
El Husseini, Nazem; Schlisser, Ava E; Hales, Barbara F
2016-08-01
Hydroxyurea, an anticancer agent and potent teratogen, induces oxidative stress and activates a DNA damage response pathway in the gestation day (GD) 9 mouse embryo. To delineate the stress response pathways activated by this drug, we investigated the effect of hydroxyurea exposure on the transcriptome of GD 9 embryos. Timed pregnant CD-1 mice were treated with saline or hydroxyurea (400 mg/kg or 600 mg/kg) on GD 9; embryonic gene and protein expression were examined 3 h later. Microarray analysis revealed that the expression of 1346 probe sets changed significantly in embryos exposed to hydroxyurea compared with controls; the P53 signaling pathway was highly affected. In addition, P53 related family members, P63 and P73, were predicted to be activated and had common and unique downstream targets. Western blot analysis revealed that active phospho-P53 was significantly increased in drug-exposed embryos; confocal microscopy showed that the translocation of phospho-P53 to the nucleus was widespread in the embryo. Furthermore, qRT-PCR showed that the expression of P53-regulated genes (Cdkn1A, Fas, and Trp53inp1) was significantly upregulated in hydroxyurea-exposed embryos; the concentration of the redox sensitive P53INP1 protein was also increased in a hydroxyurea dose-dependent fashion. Thus, hydroxyurea elicits a significant effect on the transcriptome of the organogenesis stage murine embryo, activating several key developmental signaling pathways related to DNA damage and oxidative stress. We propose that the P53 pathway plays a central role in the embryonic stress response and the developmental outcome after teratogen exposure. © The Author 2016. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Passamonti, Francesco; Griesshammer, Martin; Palandri, Francesca; Egyed, Miklos; Benevolo, Giulia; Devos, Timothy; Callum, Jeannie; Vannucchi, Alessandro M; Sivgin, Serdar; Bensasson, Caroline; Khan, Mahmudul; Mounedji, Nadjat; Saydam, Guray
2017-01-01
In the pivotal RESPONSE study, ruxolitinib, a Janus kinase (JAK)1 and JAK2 inhibitor, was superior to best available therapy at controlling haematocrit and improving splenomegaly and symptoms in patients with polycythaemia vera with splenomegaly who were inadequately controlled with hydroxyurea. In this study, we assessed the efficacy and safety of ruxolitinib in controlling disease in patients with polycythaemia vera without splenomegaly who need second-line therapy. RESPONSE-2 is a randomised, open-label, phase 3b study assessing ruxolitinib versus best available therapy in patients with polycythaemia vera done in 48 hospitals or clinics across 12 countries in Asia, Australia, Europe, and North America. Eligible patients (aged ≥18 years) with polycythaemia vera, no palpable splenomegaly, and hydroxyurea resistance or intolerance were stratified by their hydroxyurea therapy status (resistance vs intolerance) and randomly assigned (1:1) by an interactive response technology provider using a validated system to receive either oral ruxolitinib 10 mg twice daily or investigator-selected best available therapy (hydroxyurea [at the maximum tolerated dose], interferon or pegylated interferon, pipobroman, anagrelide, approved immunomodulators, or no cytoreductive treatment). Investigators and patients were not masked to treatment assignment; however, the study sponsor was masked to treatment assignment until database lock. The primary endpoint was the proportion of patients achieving haematocrit control at week 28. Analyses were done according to an intention-to-treat principle, including data from all patients randomly assigned to treatment. This study is registered with ClinicalTrials.gov (NCT02038036) and is ongoing but not recruiting patients. Between March 25, 2014, and Feb 11, 2015, of 173 patients assessed for eligibility, 74 patients were randomly assigned to receive ruxolitinib and 75 to receive best available therapy. At randomisation, best available therapy included hydroxyurea (37 [49%] of 75 in the best available therapy group), interferon or pegylated interferon (ten [13%] of 75), pipobroman (five [7%] of 75), lenalidomide (one [1%] of 75), no treatment (21 [28%] of 75), and other (one [1%] of 75). Haematocrit control was achieved in 46 (62%) of 74 ruxolitinib-treated patients versus 14 (19%) of 75 patients who received best available therapy (odds ratio 7·28 [95% CI 3·43-15·45]; p<0·0001). The most frequent haematological adverse events of any grade were anaemia (ten [14%] of 74 in the ruxolitinib group vs two [3%] of 75 in the best available therapy group) and thrombocytopenia (two [3%] vs six [8%]). No cases of grade 3-4 anaemia or thrombocytopenia occurred with ruxolitinib; one patient (1%) reported grade 3-4 anaemia and three patients (4%) reported grade 3-4 thrombocytopenia in the group receiving best available therapy. Frequent grade 3-4 non-haematological adverse events were hypertension (five [7%] of 74 vs three [4%] of 75) and pruritus (0 of 74 vs two [3%] of 75). Serious adverse events occurring in more than 2% of patients in either group, irrespective of cause, included thrombocytopenia (none in the ruxolitinib group vs two [3%] of 75 in the best available therapy group) and angina pectoris (two [3%] of 74 in the ruxolitinib group vs none in the best available therapy group). Two deaths occurred, both in the best available therapy group. RESPONSE-2 met its primary endpoint. The findings of this study indicate that ruxolitinib could be considered a standard of care for second-line therapy in this post-hydroxyurea patient population. Novartis. Copyright © 2017 Elsevier Ltd. All rights reserved.
Role of cdc25 Phosphatases in Human Breast Cancer
2007-05-01
cellular response to 5-fluorouracil or hydroxyurea . MCF-10A cells were infected with the indicated adenoviruses for 24 hr and then treated with...doxorubicin, 5-fluorouracil, or hydroxyurea for 48 hr. Cells were stained with propidium iodide prior to flow-cytometry analyses. In order to investigate...of two chemotherapeutic agents, 5- fluorouracil (5-FU, 50 μM), an inhibitor of pyrimidine synthesis, or hydroxyurea (HU, 2mM), an inhibitor of both
Centrosome Amplification: A Potential Marker of Breast Cancer Agressiveness
2006-07-01
centrosome amplification. Introduction of DNA damage in the MCF-7 cell line by treatment with hydroxyurea (HU) or daunorubicin (DR) resulted in the...cycles of DNA synthesis and mitotic division in hydroxyurea - arrested Chinese hamster ovary cells. J Cell Biol, 130: 105-115, 1995. 23. D’Assoro, A. B...from cycles of DNA synthesis and mitotic division in hydroxyurea -arrested Chinese hamster ovary cells. J Cell Biol, 1995. 130(1): p. 105-15. 22
da Silva, Luiz Bernardino Lima; Ivo, Maria Lúcia; de Souza, Albert Schiaveto; Pontes, Elenir Rose Jardim Cury; Pinto, Alexandra Maria Almeida Carvalho; de Araujo, Olinda Maria Rodrigues
2012-01-01
Objective To assess the burden and quality of life of caregivers of patients with sickle cell anemia taking hydroxyurea versus those of patients not taking hydroxyurea. Methods A cross-sectional study was performed of caregivers of outpatients with sickle cell anemia in two public hospitals in Campo Grande, MS, from January through June 2010. The World Health Organization Quality of Life-BREF Scale and the Caregiver Burden Scale were used. Results Of the 37 caregivers in this study, 81.1% were women, 73.0% were mothers, 59.5% were married, 54.1%were mulattos, 48.6% were housewives, 54.1% had family incomes of up to one minimum wage and 75.7% had onlycompleted elementary education. The mean duration of care provided (time after diagnosis) was 16.08 ± 9.88 yearsand 89.2% reported that they provided 24-hour care. Regarding health, 27.0% of study participants reported having physical and 13.5% emotional problems. There were no significant relationships between these variables either with the different domains or the total score of the WHOQOL-BREF comparing caregivers of patients taking hydroxyurea versusthose of patients not taking hydroxyurea. There was a moderate negative linear correlation between the WHOQOL-BREF and the Caregiver Burden Scale scores (linear correlation test of Pearson: p-value = 0.003, r = -0.477). The burden of caregivers of patients who did not take hydroxyurea was significantly higher than those of patients who took the medication in terms of general tension, disappointment, environment and total score (student t-test: p-value < 0.05). Conclusion In the perception of the caregiver, looking after sickle cell anemia patients represents a moderate negative burden. PMID:23049439
Dong, Min; McGann, Patrick T; Mizuno, Tomoyuki; Ware, Russell E; Vinks, Alexander A
2016-04-01
Hydroxyurea has emerged as the primary disease-modifying therapy for patients with sickle cell anaemia (SCA). The laboratory and clinical benefits of hydroxyurea are optimal at maximum tolerated dose (MTD), but the current empirical dose escalation process often takes up to 12 months. The purpose of this study was to develop a pharmacokinetic-guided dosing strategy to reduce the time required to reach hydroxyurea MTD in children with SCA. Pharmacokinetic (PK) data from the HUSTLE trial (NCT00305175) were used to develop a population PK model using non-linear mixed effects modelling (nonmem 7.2). A D-optimal sampling strategy was developed to estimate individual PK and hydroxyurea exposure (area under the concentration-time curve (AUC)). The initial AUC target was derived from HUSTLE clinical data and defined as the mean AUC at MTD. PK profiles were best described by a one compartment with Michaelis-Menten elimination and a transit absorption model. Body weight and cystatin C were identified as significant predictors of hydroxyurea clearance. The following clinically feasible sampling times are included in a new prospective protocol: pre-dose (baseline), 15-20 min, 50-60 min and 3 h after an initial 20 mg kg(-1) oral dose. The mean target AUC(0,∞) for initial dose titration was 115 mg l(-1) h. We developed a PK model-based individualized dosing strategy for the prospective Therapeutic Response Evaluation and Adherence Trial (TREAT, ClinicalTrials.gov NCT02286154). This approach has the potential to optimize the dose titration of hydroxyurea therapy for children with SCA, such that the clinical benefits at MTD are achieved more quickly. © 2015 The British Pharmacological Society.
Dong, Min; McGann, Patrick T.; Mizuno, Tomoyuki; Ware, Russell E.
2016-01-01
AIMS Hydroxyurea has emerged as the primary disease‐modifying therapy for patients with sickle cell anaemia (SCA). The laboratory and clinical benefits of hydroxyurea are optimal at maximum tolerated dose (MTD), but the current empirical dose escalation process often takes up to 12 months. The purpose of this study was to develop a pharmacokinetic‐guided dosing strategy to reduce the time required to reach hydroxyurea MTD in children with SCA. Methods Pharmacokinetic (PK) data from the HUSTLE trial (NCT00305175) were used to develop a population PK model using non‐linear mixed effects modelling (nonmem 7.2). A D‐optimal sampling strategy was developed to estimate individual PK and hydroxyurea exposure (area under the concentration–time curve (AUC)). The initial AUC target was derived from HUSTLE clinical data and defined as the mean AUC at MTD. Results PK profiles were best described by a one compartment with Michaelis–Menten elimination and a transit absorption model. Body weight and cystatin C were identified as significant predictors of hydroxyurea clearance. The following clinically feasible sampling times are included in a new prospective protocol: pre‐dose (baseline), 15–20 min, 50–60 min and 3 h after an initial 20 mg kg–1 oral dose. The mean target AUC(0,∞) for initial dose titration was 115 mg l–1 h. Conclusion We developed a PK model‐based individualized dosing strategy for the prospective Therapeutic Response Evaluation and Adherence Trial (TREAT, ClinicalTrials.gov NCT02286154). This approach has the potential to optimize the dose titration of hydroxyurea therapy for children with SCA, such that the clinical benefits at MTD are achieved more quickly. PMID:26615061
Cytologic Effects of Air Force Chemicals
1978-09-01
pCi/ml, 60 Ci/mmole), hydroxyurea (10- 2M) to suppress replicative DNA synthesis, and with or without 4-nitroquinoline-l-oxide (4NQO, a DNA-damaging...organ cultures. The tissues were minced in cold, buffered saline and then incubated with 3 H-thymidine, hydroxyurea and 4NQO to damage cellular DNA...incorporation under these conditions is taken as an indication of DNA repair activity, and incorporation of 3H-thymidine in the absence of hydroxyurea and
Mamez, Anne-Claire; Raffoux, Emmanuel; Chevret, Sylvie; Lemiale, Virginie; Boissel, Nicolas; Canet, Emmanuel; Schlemmer, Benoît; Dombret, Hervé; Azoulay, Elie; Lengliné, Etienne
2016-10-01
Acute myeloid leukemia with high white blood cell count (WBC) is a medical emergency. A reduction of tumor burden with hydroxyurea may prevent life-threatening complications induced by straight chemotherapy. To evaluate this strategy, we reviewed medical charts of adult patients admitted to our institution from 1997 to 2011 with non-promyelocytic AML and WBC over 50 G/L. One hundred and sixty patients were included with a median WBC of 120 G/L (range 50-450), 107 patients received hydroxyurea prior to chemotherapy, and 53 received emergency induction chemotherapy (CT). Hospital mortality was lower for patients treated with hydroxyurea (34% versus 19%, p = 0.047) even after adjusting for age (p < 0.01) and initial WBC count (p = 0.02). No evidence of any difference between treatment groups in terms of WBC decline kinetics and disease free survival (p = 0.87) was found. Oral hydroxyurea prior to chemotherapy seems a safe and efficient strategy to reduce early death of hyperleukocytic AML patients.
Hydroxyurea for reducing blood transfusion in non-transfusion dependent beta thalassaemias.
Foong, Wai Cheng; Ho, Jacqueline J; Loh, C Khai; Viprakasit, Vip
2016-10-18
Non-transfusion dependent beta thalassaemia is a subset of inherited haemoglobin disorders characterised by reduced production of the beta globin chain of the haemoglobin molecule leading to anaemia of varying severity. Although blood transfusion is not a necessity for survival, it is required when episodes of chronic anaemia occur. This chronic anaemia can impair growth and affect quality of life. People with non-transfusion dependent beta thalassaemia suffer from iron overload due to their body's increased capability of absorbing iron from food sources. Iron overload becomes more pronounced in those requiring blood transfusion. People with a higher foetal haemoglobin level have been found to require fewer blood transfusions. Hydroxyurea has been used to increase foetal haemoglobin level; however, its efficacy in reducing transfusion, chronic anaemia complications and its safety need to be established. To assess the effectiveness, safety and appropriate dose regimen of hydroxyurea in people with non-transfusion dependent beta thalassaemia (haemoglobin E combined with beta thalassaemia and beta thalassaemia intermedia). We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register, compiled from electronic database searches and handsearching of relevant journals. We also searched ongoing trials registries and the reference lists of relevant articles and reviews.Date of last search: 30 April 2016. Randomised or quasi-randomised controlled trials of hydroxyurea in people with non-transfusion dependent beta thalassaemia comparing hydroxyurea with placebo or standard treatment or comparing different doses of hydroxyurea. Two authors independently applied the inclusion criteria in order to select trials for inclusion. Both authors assessed the risk of bias of trials and extracted the data. A third author verified these assessments. No trials comparing hydroxyurea with placebo or standard care were found. However, we included one randomised controlled trial (n = 61) comparing 20 mg/kg/day with 10 mg/kg/day of hydroxyurea for 24 weeks.Both haemoglobin and foetal haemoglobin levels were lower at 24 weeks in the 20 mg group compared with the 10 mg group, mean difference -2.39 (95% confidence interval - 2.8 to -1.98) and mean difference -1.5 (95% confidence interval -1.83 to -1.17), respectively. Major adverse effects were significantly more common in the 20 mg group, for neutropenia risk ratio 9.93 (95% confidence interval 1.34 to 73.97) and for thrombocytopenia risk ratio 3.68 (95% confidence interval 1.13 to 12.07). No difference was reported for minor adverse effects (gastrointestinal disturbances and raised liver enzymes). The effect of hydroxyurea on transfusion frequency was not reported.The overall quality for the outcomes reported was graded as very low mainly because the outcomes were derived from only one small study with an unclear method of allocation concealment. There is no evidence from randomised controlled trials to show whether hydroxyurea has any effect compared with controls on the need for blood transfusion. Administration of 10 mg/kg/day compared to 20 mg/kg/day of hydroxyurea resulted in higher haemoglobin levels and seems safer with fewer adverse effects. It has not been reported whether hydroxyurea is capable of reducing the need for blood transfusion. Large well-designed randomised controlled trials with sufficient duration of follow up are recommended.
Kubesova, B; Pavlova, S; Malcikova, J; Kabathova, J; Radova, L; Tom, N; Tichy, B; Plevova, K; Kantorova, B; Fiedorova, K; Slavikova, M; Bystry, V; Kissova, J; Gisslinger, B; Gisslinger, H; Penka, M; Mayer, J; Kralovics, R; Pospisilova, S; Doubek, M
2018-01-01
The multistep process of TP53 mutation expansion during myeloproliferative neoplasm (MPN) transformation into acute myeloid leukemia (AML) has been documented retrospectively. It is currently unknown how common TP53 mutations with low variant allele frequency (VAF) are, whether they are linked to hydroxyurea (HU) cytoreduction, and what disease progression risk they carry. Using ultra-deep next-generation sequencing, we examined 254 MPN patients treated with HU, interferon alpha-2a or anagrelide and 85 untreated patients. We found TP53 mutations in 50 cases (0.2–16.3% VAF), regardless of disease subtype, driver gene status and cytoreduction. Both therapy and TP53 mutations were strongly associated with older age. Over-time analysis showed that the mutations may be undetectable at diagnosis and slowly increase during disease course. Although three patients with TP53 mutations progressed to TP53-mutated or TP53-wild-type AML, we did not observe a significant age-independent impact on overall survival during the follow-up. Further, we showed that complete p53 inactivation alone led to neither blast transformation nor HU resistance. Altogether, we revealed patient's age as the strongest factor affecting low-burden TP53 mutation incidence in MPN and found no significant age-independent association between TP53 mutations and hydroxyurea. Mutations may persist at low levels for years without an immediate risk of progression. PMID:28744014
Liu, Xianpeng; Lee, Yong Joo; Liou, Liang-Chun; Ren, Qun; Zhang, Zhaojie; Wang, Shaoxiao; Witt, Stephan N.
2011-01-01
Hydroxyurea (HU) inhibits ribonucleotide reductase (RNR), which catalyzes the rate-limiting synthesis of deoxyribonucleotides for DNA replication. HU is used to treat HIV, sickle-cell anemia and some cancers. We found that, compared with vector control cells, low levels of alpha-synuclein (α-syn) protect S. cerevisiae cells from the growth inhibition and reactive oxygen species (ROS) accumulation induced by HU. Analysis of this effect using different α-syn mutants revealed that the α-syn protein functions in the nucleus and not the cytoplasm to modulate S-phase checkpoint responses: α-syn up-regulates histone acetylation and RNR levels, maintains helicase minichromosome maintenance protein complexes (Mcm2–7) on chromatin and inhibits HU-induced ROS accumulation. Strikingly, when residues 2–10 or 96–140 are deleted, this protective function of α-syn in the nucleus is abolished. Understanding the mechanism by which α-syn protects against HU could expand our knowledge of the normal function of this neuronal protein. PMID:21642386
Verstovsek, Srdan; Passamonti, Francesco; Rambaldi, Alessandro; Barosi, Giovanni; Rosen, Peter J; Rumi, Elisa; Gattoni, Elisabetta; Pieri, Lisa; Guglielmelli, Paola; Elena, Chiara; He, Shui; Contel, Nancy; Mookerjee, Bijoyesh; Sandor, Victor; Cazzola, Mario; Kantarjian, Hagop M; Barbui, Tiziano; Vannucchi, Alessandro M
2014-02-15
Polycythemia vera (PV) is a myeloproliferative neoplasm associated with somatic gain-of-function mutations of Janus kinase-2 (JAK2). Therapeutic options are limited in patients with advanced disease. Ruxolitinib, an oral JAK1/JAK2 inhibitor, is active in preclinical models of PV. The long-term efficacy and safety of ruxolitinib in patients with advanced PV who are refractory or intolerant to hydroxyurea were studied in a phase 2 trial. Response was assessed using modified European LeukemiaNet criteria, which included a reduction in hematocrit to <45% without phlebotomy, resolution of palpable splenomegaly, normalization of white blood cell and platelet counts, and reduction in PV-associated symptoms. Thirty-four patients received ruxolitinib for a median of 152 weeks (range, 31 weeks-177 weeks) or 35.0 months (range, 7.1 months-40.7 months). Hematocrit <45% without phlebotomy was achieved in 97% of patients by week 24.Only 1 patient required a phlebotomy after week 4. Among patients with palpable splenomegaly at baseline, 44% and 63%, respectively, achieved nonpalpable spleen measurements at weeks 24 and 144. Clinically meaningful improvements in pruritus, night sweats, and bone pain were observed within 4 weeks of the initiation of therapy and maintained with continued treatment. Ruxolitinib treatment also reduced elevated levels of inflammatory cytokines and granulocyte activation. Thrombocytopenia and anemia were the most common adverse events.Thrombocytopenia of grade 3 or anemia of grade 3 (according to National Cancer Institute Common Terminology Criteria for Adverse Events,version 3.0) occurred in 3 patients each (9%) (1 patient had both) and were managed with dose modification. Ruxolitinib was generally well tolerated and provided rapid and durable clinical benefits in patients with advanced PV who were refractory or intolerant to hydroxyurea.
A patient case highlighting the myriad of cutaneous adverse effects of prolonged use of hydroxyurea.
Neill, Brett; Ryser, Ted; Neill, John; Aires, Daniel; Rajpara, Anand
2017-11-15
Hydroxyurea is an antimetabolite primarily used to treat myeloproliferative disorders, and chronic treatment is associated with many cutaneous adverse effects ranging in severity from ichthyosis to aggressive nonmelanoma skin cancer. We report a 67-year-oldman with a history of polycythemia vera who was referred for management of progressively worsening dorsal hand lesions. The patient presented withhyperpigmentation, ichthyosis, plantar keratoderma, dermatomyositis-like eruptions, two squamous cell carcinomas, and actinic keratoses. The adversereactions observed were acknowledged to be related to chronic hydroxyurea use. The patient underwent Mohs excision of the squamous cell carcinomas and thehydroxyurea was promptly discontinued; subsequent cutaneous improvement of the dermatomyositislike lesions ensued. Another clinically suspicious aggressive squamous cell carcinoma was suspected and the patient was referred to the plastic surgery department for complete excision because of the size of the lesion. The patient remains on periodic dermatology follow up. We report a case that exemplifies the cutaneous adverse effects of chronic hydroxyurea therapy. Although many cases improve after drug discontinuation, strict photoprotection and ongoing surveillance are indicated given the recently proposed premalignant potential of dermatomyositis-like eruptions and the aggressive nature of hydroxyurea-induced nonmelanoma skin cancer.
Hydroxyurea (hydroxycarbamide) for sickle cell disease.
Nevitt, Sarah J; Jones, Ashley P; Howard, Jo
2017-04-20
Sickle cell disease (SCD) is one of the most common inherited diseases worldwide. It is associated with lifelong morbidity and a reduced life expectancy. Hydroxyurea (hydroxycarbamide), an oral chemotherapeutic drug, ameliorates some of the clinical problems of SCD, in particular that of pain, by raising fetal haemoglobin. This is an update of a previously published Cochrane Review. To assess the effects of hydroxyurea therapy in people with SCD (all genotypes), of any age, regardless of setting. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Register, comprising of references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. We also searched online trial registries.Date of the most recent search: 16 January 2017. Randomised and quasi-randomised controlled trials, of one month or longer, comparing hydroxyurea with placebo, standard therapy or other interventions for people with SCD. Authors independently assessed studies for inclusion, carried out data extraction and assessed the risk of bias. Seventeen studies were identified in the searches; eight randomised controlled trials were included, recruiting 899 adults and children with SCD (haemoglobin SS (HbSS), haemoglobin SC (HbSC) or haemoglobin Sβºthalassaemia (HbSβºthal) genotypes). Studies lasted from six to 30 months.Four studies (577 adults and children with HbSS or HbSβºthal) compared hydroxyurea to placebo; three recruited individuals with only severe disease and one recruited individuals with all disease severities. There were statistically significant improvements in terms of pain alteration (using measures such as pain crisis frequency, duration, intensity, hospital admissions and opoid use), measures of fetal haemoglobin and neutrophil counts and fewer occurrences of acute chest syndrome and blood transfusions in the hydroxyurea groups. There were no consistent statistically significant differences in terms of quality of life and adverse events (including serious or life-threatening events). Seven deaths occurred during the studies, but the rates by treatment group were not statistically significantly different.Two studies (254 children with HbSS or HbSβºthal also with risk of primary or secondary stroke) compared hydroxyurea and phlebotomy to transfusion and chelation; there were statistically significant improvements in terms of measures of fetal haemoglobin and neutrophil counts, but more occurrences of acute chest syndrome and infections in the hydroxyurea and phlebotomy group. There were no consistent statistically significant differences in terms of pain alteration and adverse events (including serious or life-threatening events). Two deaths occurred during the studies (one in a the hydroxyurea treatment arm and one in the control arm), but the rates by treatment group were not statistically significantly different. In the primary prevention study, no strokes occurred in either treatment group but in the secondary prevention study, seven strokes occurred in the hydroxyurea and phlebotomy group (none in the transfusion and chelation group) and the study was terminated early.The quality of the evidence for the above two comparisons was judged as moderate to low as the studies contributing to these comparisons were mostly large and well designed (and at low risk of bias); however evidence was limited and imprecise for some outcomes such as quality of life, deaths during the studies and adverse events and results are applicable only to individuals with HbSS and HbSβºthal genotypes.Of the remaining two studies, one (22 children with HbSS or HbSβºthal also at risk of stoke) compared hydroxyurea to observation; there were statistically significant improvements in terms of measures of fetal haemoglobin and neutrophil counts but no statistically significant differences in terms of adverse events (including serious or life-threatening events).The final study (44 adults and children with HbSC) compared treatment regimens with and without hydroxyurea - there was statistically significant improvement in terms of measures of fetal haemoglobin, but no statistically significant differences in terms of adverse events (including serious or life-threatening events). No participants died in either of these studies and other outcomes relevant to the review were not reported.The quality of the evidence for the above two comparisons was judged to be very low due to the limited number of participants, the lack of statistical power (as both studies were terminated early with approximately only 20% of their target sample size recruited) and the lack of applicability to all age groups and genotypes. There is evidence to suggest that hydroxyurea is effective in decreasing the frequency of pain episodes and other acute complications in adults and children with sickle cell anaemia of HbSS or HbSβºthal genotypes and in preventing life-threatening neurological events in those with sickle cell anaemia at risk of primary stroke by maintaining transcranial doppler velocities. However, there is still insufficient evidence on the long-term benefits of hydroxyurea, particularly in preventing chronic complications of SCD, recommending a standard dose or dose escalation to maximum tolerated dose. There is also insufficient evidence about the long-term risks of hydroxyurea, including its effects on fertility and reproduction. Evidence is also limited on the effects of hydroxyurea on individuals with HbSC genotype. Future studies should be designed to address such uncertainties.
Nottage, Kerri A; Ware, Russell E; Winter, Bryan; Smeltzer, Matthew; Wang, Winfred C; Hankins, Jane S; Dertinger, Stephen D; Shulkin, Barry; Aygun, Banu
2014-11-01
More than 90% of children with sickle cell anemia (SCA) lose splenic function by the age of 2 yrs. Splenic function may improve with hydroxyurea, but previous studies are conflicting. We prospectively evaluated the effect of hydroxyurea on splenic filtrative function. Children with SCA enrolled in the Hydroxyurea Study of Long-Term Effects (HUSTLE-NCT00305175) underwent clinical evaluations including Tc(99) m liver-spleen (LS) scans before hydroxyurea initiation and after 3 yrs of treatment to maximum tolerated dose (MTD). LS scans were classified as follows: no uptake, <10% uptake, decreased but ≥10% uptake, and normal. Mean age (N = 40) was 9.1 yrs, range 2.3-17.0. After 3 yrs of treatment, 13 (33%) had uptake on LS scan. These 13 children were younger (median age 6.0 vs. 10.6 yrs, P = 0.008), had a higher HbF at baseline (mean 10.2% vs. 5.8%, P = 0.004) and after 3 yrs (22.9% vs. 13.9%, P < 0.001), achieved MTD more rapidly (median 288 vs. 358 d, P = 0.021), and were more likely to have baseline splenic uptake (P < 0.001). Hydroxyurea at MTD is associated with preserved or improved splenic filtrative function, with 33% demonstrating LS scan uptake after 3 yrs. Younger age, higher %HbF, and baseline splenic function are associated with a favorable outcome. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Evaluation of γ-Induced Apoptosis in Human Peripheral Blood Lymphocytes
NASA Astrophysics Data System (ADS)
Baranova, Elena; Boreyko, Alla; Ravnachka, Ivanka; Saveleva, Maria
2010-01-01
Several experiments have been performed to study regularities in the induction of apoptotic cells in human lymphocytes by 60Co γ-rays at different times after irradiation. Apoptosis induction by 60Co γ-rays in human lymphocytes in different cell cycle phases (G0, S, G1, and G2) has been studied. The maximal apoptosis output in lymphocyte cells was observed in the S phase. Modifying effect of replicative and reparative DNA synthesis inhibitors—1- β -D-arabinofuranosylcytosine (Ara-C) and hydroxyurea (Hu)—on the kinetics of 60Co γ-rays induced apoptosis in human lymphocytes has been studied.
Kassim, Adetola A; DeBaun, Michael R
2014-02-01
The perception of an asymptomatic sickle cell disease (SCD) state is a misnomer. Children without overt symptoms, likely have subclinical disease beginning in infancy with progression into adulthood. Predictive models of SCD severity are unable to predict a subgroup of asymptomatic children likely to develop severe SCD. The introduction of penicillin prophylaxis, conjugated pneumococcal and Haemophilus influenzae type B vaccines have dramatically decreased the rate of life-threatening infections, while use of hydroxyurea in children has decreased pain and acute chest syndrome events. Use of transcranial Doppler coupled with regular blood transfusion therapy has decreased the rate of overt strokes and premature death associated with strokes. Currently, therapy for asymptomatic children includes hydroxyurea, regular blood transfusion or allogeneic hematopoietic stem cell transplant (allo-HSCT). The pros and cons of initiating hydroxyurea, regular blood transfusion or allo-HSCT in asymptomatic children with SCD. Emerging evidence from observational studies indicates that hydroxyurea prolongs survival in children and adults with sickle cell anemia. Regular blood transfusions reduce incidence of strokes, acute chest and pain episodes, but is associated with the burden of monthly visits and excessive iron stores. Although curative, the perceived risk:benefit ratio associated with allo-HSCT limits its use in asymptomatic children.
Hydroxyurea for Treatment of Nephrotic Syndrome Associated With Polycythemia Vera.
Hundemer, Gregory L; Rosales, Ivy A; Chen, Yi-Bin; Colvin, Robert B; Tolkoff-Rubin, Nina E
2016-09-01
Myeloproliferative disorders are a rare cause of focal segmental glomerulosclerosis (FSGS), although the mechanism is unclear. Hydroxyurea is commonly used in these disorders for its cytoreductive properties; however, the effect of this treatment on proteinuria or kidney function remains unclear in cases of myeloproliferative disorder-associated FSGS. We describe the clinical course of a patient with polycythemia vera and nephrotic-range proteinuria, demonstrated to have FSGS on biopsy. The patient had a distant history of granulomatosis with polyangiitis (Wegener's), for which he routinely had his kidney function and proteinuria measured, allowing for early detection of nephrotic syndrome soon after being diagnosed with polycythemia vera. Treatment with hydroxyurea resulted in rapid improvement in proteinuria that correlated with a decrease in hematocrit. This response was replicated 2 additional times when the patient was taken off and then restarted on hydroxyurea therapy. He now maintains a steady dose of hydroxyurea with favorable kidney measures (proteinuria with <1g/d of protein excretion and serum creatinine of 1.27mg/dL [corresponding to estimated glomerular filtration rate of 56mL/min/1.73 m(2)]). This case suggests that early screening and treatment for myeloproliferative disorder-associated FSGS may lead to improved long-standing kidney function. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.
Structure and stability of the N-hydroxyurea dimer: Post-Hartree-Fock quantum mechanical study
NASA Astrophysics Data System (ADS)
Jabalameli, Ali; Venkatraman, Ramaiyer; Nowek, Andrzej; Sullivan, Richard H.
2000-10-01
The potential energy surface (PES) search of the N-hydroxyurea dimer was searched with second-order Møller-Plesset perturbation theory (MP2) and the 6-31G(d,p) basis set. Eight local minimum energy structures have been found. Four of them have relatively strong (ΔE˜-10 to -13 kcal/mol) intermolecular interactions and the others are moderately strongly interacting species (ΔE˜-3 to -7 kcal/mol). Final estimation of interaction energies was performed using the larger 6-311G(df,pd) and 6-311G(2df,2pd) basis sets. The predicted interaction energies are ΔE=-14.26 kcal/mol and -3.43 kcal/mol for the strongest and the weakest interacting forms of the studied complex, respectively, at the MP2/6-311G(2df,2pd)//MP2/6-31G(d,p) level of theory. The self-consistent field (SCF) interaction energy decomposition indicates the important influence of the deformation term magnitude on ΔE(SCF). The calculated electron correlation contribution to ΔE(MP2) depends on the geometry of the system and varies from -0.5 to -5 kcal/mol. The estimated influence of water on the stability (free energy of hydration) of N-hydroxyurea dimers using the self-consistent isodensity polarized continuum (SCI-PCM) model of solvation varies from ˜-11 kcal/mol to ˜-21 kcal/mol. The forms predicted to be more strongly interacting species in gas phase are less influenced by hydration than the more weakly interacting ones.
Inhibition of Mutation: A Novel Approach to Preventing and Treating Cancer
2007-06-01
Hydroxyurea (HU) is a small molecule chemotherapeutic that is thought to slow tumor growth by inhibiting RNR and thus reducing dNTP...Identification of hydroxyurea as an inhibitor of induced mutation that presumably acts by inhibiting ribonucleotide reductase and thereby decreasing the
Estepp, Jeremie H; Melloni, Chiara; Thornburg, Courtney D; Wiczling, Paweł; Rogers, Zora; Rothman, Jennifer A; Green, Nancy S; Liem, Robert; Brandow, Amanda M; Crary, Shelley E; Howard, Thomas H; Morris, Maurine H; Lewandowski, Andrew; Garg, Uttam; Jusko, William J; Neville, Kathleen A
2016-03-01
Hydroxyurea (HU) is a crucial therapy for children with sickle cell anemia, but its off-label use is a barrier to widespread acceptance. We found HU exposure is not significantly altered by liquid vs capsule formulation, and weight-based dosing schemes provide consistent exposure. HU is recommended for all children starting as young as 9 months of age with sickle cell anemia (SCA; HbSS and HbSβspan(0) thalassemia); however; a paucity of pediatric data exists regarding the pharmacokinetics (PK) or the exposure-response relationship of HU. This trial aimed to characterize the PK of HU in children and to evaluate and compare the bioavailability of a liquid vs capsule formulation. This multicenter; prospective; open-label trial enrolled 39 children with SCA who provided 682 plasma samples for PK analysis following administration of HU. Noncompartmental and population PK models are described. We report that liquid and capsule formulations of HU are bioequivalent; weight-based dosing schemes provide consistent drug exposure; and age-based dosing schemes are unnecessary. These data support the use of liquid HU in children unable to swallow capsules and in those whose weight precludes the use of fixed capsule formulations. Taken with existing safety and efficacy literature; these findings should encourage the use of HU across the spectrum of age and weight in children with SCA; and they should facilitate the expanded use of HU as recommended in the National Heart; Lung; and Blood Institute guidelines for individuals with SCA. © 2015, The American College of Clinical Pharmacology.
Strouse, John J.; Heeney, Matthew M.
2012-01-01
Hydroxyurea is the only approved medication in the United States for the treatment of sickle cell anemia (HbSS) and is widely used in children despite an indication limited to adults. We review the evidence of efficacy and safety in children with reference to pivotal adult studies. This evidence and expert opinion form the basis for recommended guidelines for the use of hydroxyurea in children including indications, dosing, therapeutic and safety monitoring, and interventions to improve adherence. However, there are substantial gaps in our knowledge to be addressed by on-going and planned studies in children. PMID:22517797
Role of Merlin in the Growth and Transformation of Arachnoidal Cells
2009-01-01
studies on the chemotherapeutic agent, hydroxyurea , were performed using meningioma cells grown in the galea (25), and tests on celecoxib were performed...Anders M, Kiesewetter F, Marschalek R, Koch UH, Fahlbusch R (1997) Hydroxyurea for treatment of unresectable and recurrent meningiomas. I. Inhibition of
Ahmad, Fahd A; Macias, Charles G; Allen, Joseph Y
2011-08-01
To determine if incentive spirometry (IS) in pediatric patients admitted with sickle cell disease for nonrespiratory complaints will decrease acute chest syndrome (ACS). This was an Institutional Review Board-approved before-after 2-year retrospective cohort study evaluating an evidence-based guideline (EBG) initiating mandatory IS in admitted pediatric sickle cell patients from a tertiary children's emergency center. Student t testing and χ² analysis were performed. There were 1551 patient visits. About 258 visits were enrolled in the pre-EBG year, and 230 in the EBG year. Between year characteristics were similar. The EBG year reported higher use of hydroxyurea (P<0.01), analgesics (P=0.02), and chest pain (P=0.03). Sixty-seven patients (25.9%) in the pre-EBG year received transfusions versus 51 (22.5%) in the EBG year (NS). Twenty-five (9.6%) of the pre-EBG patients received blood for ACS versus 14 (6.1%) in the EBG group (absolute risk reduction: 3.5%, 95% confidence interval: -1-8.4%). Subgroup analysis revealed that patients who presented with back pain experienced a significant decrease in the development of ACS in the EBG year (P=0.04, absolute risk reduction: 14%, 95% confidence interval: 1-28%, number needed to treat: 8). Mandatory IS for sickle cell disease patients admitted without respiratory complaints reduces transfusions and ACS, particularly for those presenting with back pain.
Estepp, Jeremie H; Smeltzer, Matthew P; Kang, Guolian; Li, Chen; Wang, Winfred C; Abrams, Christina; Aygun, Banu; Ware, Russell E; Nottage, Kerri; Hankins, Jane S
2017-12-01
Hydroxyurea has proven clinical benefits and is recommended to be offered to all children with sickle cell anemia (SCA), but the optimal dosing regimen remains controversial. Induction of red blood cell fetal hemoglobin (HbF) by hydroxyurea appears to be dose-dependent. However, it is unknown whether maximizing HbF% improves clinical outcomes. HUSTLE (NCT00305175) is a prospective observational study with a primary goal of describing the long-term clinical effects of hydroxyurea escalated to maximal tolerated dose (MTD) in children with SCA. In 230 children, providing 610 patient-years of follow up, the mean attained HbF% at MTD was >20% for up to 4 years of follow-up. When HbF% values were ≤20%, children had twice the odds of hospitalization for any reason (P < .0001), including vaso-occlusive pain (P < .01) and acute chest syndrome (ACS) (P < .01), and more than four times the odds of admission for fever (P < .001). Thirty day readmission rates were not affected by HbF%. Neutropenia (ANC <1000 × 10 6 /L) was rare (2.3% of all laboratory monitoring), transient, and benign. Therefore, attaining HbF >20% was associated with fewer hospitalizations without significant toxicity. These data support the use of hydroxyurea in children, and suggest that the preferred dosing strategy is one that targets a HbF endpoint >20%. © 2017 Wiley Periodicals, Inc.
NASA Technical Reports Server (NTRS)
Regelson, W.; West, B.; Depaola, D. P.
1978-01-01
Simultaneous treatment utilizing pulsed radiowave and cancer chemotherapy significantly extended the life span of mice with Lewis lung transplanted carcinoma. In comparison with nontreated controls, the combination of hydroxyurea and whole body nonionizing EM radiation (at 27.12 MHz) produced differential enhancement of longevity depending on hydroxyurea combined with highest power output achieved by pulsing the radiation 600 times per second; at a 3.9% duty cycle, peak watts = 975 produced the mean extension of life 67% greater than that of the group treated with hydroxyurea alone.
Sickle Cell Disease with Cyanotic Congenital Heart Disease: Long-Term Outcomes in 5 Children.
Iannucci, Glen J; Adisa, Olufolake A; Oster, Matthew E; McConnell, Michael; Mahle, William T
2016-12-01
Sickle cell disease is a risk factor for cerebrovascular accidents in the pediatric population. This risk is compounded by hypoxemia. Cyanotic congenital heart disease can expose patients to prolonged hypoxemia. To our knowledge, the long-term outcome of patients who have combined sickle cell and cyanotic congenital heart disease has not been reported. We retrospectively reviewed patient records at our institution and identified 5 patients (3 girls and 2 boys) who had both conditions. Their outcomes were uniformly poor: 4 died (age range, 12 mo-17 yr); 3 had documented cerebrovascular accidents; and 3 developed ventricular dysfunction. The surviving patient had developmental delays. On the basis of this series, we suggest mitigating hypoxemia, and thus the risk of stroke, in patients who have sickle cell disease and cyanotic congenital heart disease. Potential therapies include chronic blood transfusions, hydroxyurea, earlier surgical correction to reduce the duration of hypoxemia, and heart or bone marrow transplantation.
Clinic Attendance of Youth With Sickle Cell Disease on Hydroxyurea Treatment.
Ingerski, Lisa M; Arnold, Trisha L; Banks, Gabrielle; Porter, Jerlym S; Wang, Winfred C
2017-07-01
The objective of this study is to describe rates of clinic attendance of youth with sickle cell disease prescribed hydroxyurea and examine potential demographic and medical factors related to consistent clinic attendance. Participants included 148 youth diagnosed with sickle cell disease and prescribed hydroxyurea during a single calendar year. Clinic attendance and potential demographic and medical factors related to attendance were extracted via systematic retrospective medical chart review. Youth attended 90.3% of scheduled appointments and 85.1% of youth attended at least 80% of scheduled clinic appointments during the study window. Adjusting for other factors, multivariate analysis revealed families with fewer children in the household, families with private insurance, youth experiencing fever, and youth not experiencing pain during the calendar year were more likely to consistently attend clinic visits. Adherence to clinic appointments is critical to optimizing health outcomes for youth with sickle cell disease and integral for adequate monitoring of youth prescribed hydroxyurea, in particular. Findings may aid providers in appropriately identifying possible barriers to clinic attendance to develop attendance promotion interventions.
Badawy, Sherif M; Thompson, Alexis A; Penedo, Frank J; Lai, Jin-Shei; Rychlik, Karen; Liem, Robert I
2017-06-01
To identify barriers to hydroxyurea adherence (negative beliefs, access, and/or recall barriers), and their relationship to adherence rates and health-related quality of life (HRQOL) among adolescents and young adults (AYA) with sickle cell disease (SCD). A cross-sectional survey was administered to 34 AYAs (12-22 years old) in SCD clinics from January to December 2015. Study measures included Brief Medication Questionnaire, Modified Morisky Adherence Scale 8-items, visual analog scale, and Patient Reported Outcomes Measurement Information System. Participants (59% male; 91% Black) had a median age of 13.5 years (IQR 12-18). Participants reported negative beliefs (32%), recall barriers (44%), and access barriers (32%). Participants with recall barriers reported worse pain (P=.02), fatigue (P=.05), and depression (P=.05). The number of adherence barriers inversely correlated with adherence level using ©MMAS-8 (r s =-.38, P=.02) and VAS dose (r s =-.25, P=.14) as well as MCV (r s =-.45, P=.01) and HbF% (r s =-.36, P=.05), suggesting higher hydroxyurea adherence in patients with fewer barriers. Patients with fewer barriers to hydroxyurea adherence were more likely to have higher adherence rates and better HRQOL scores. Routine assessment of hydroxyurea adherence and its related barriers could provide actionable information to improve adherence rates, HRQOL, and other clinical outcomes. © 2017 The Authors. European Journal of Haematology Published by John Wiley & Sons Ltd.
Body Mass Index and the Association With Vaso-occlusive Crises in Pediatric Sickle Cell Disease.
Zivot, Andrea; Apollonsky, Nataly; Gracely, Edward; Raybagkar, Deepti
2017-05-01
Children with sickle cell disease (SCD) historically have been underweight and have poor overall growth. Recent studies have demonstrated a trend toward obesity in pediatric SCD populations. Through retrospective chart review of patients with SCD followed at our center, we collected patient's data, including body mass index (BMI), weight percentiles, sickle cell genotype, baseline hemoglobin, medical and psychiatric comorbidities, 25-hydroxy vitamin D level, treatment with hydroxyurea, and chronic transfusions. We identified hospitalizations to St. Christopher's Hospital for vaso-occlusive crisis (VOC) and duration of hospitalization and intravenous opioid use were recorded. Student t test, Mann-Whitney U test, and analysis of variance were used to examine associations between variables and frequency and duration of hospitalizations for VOC. Among 328 patients with SCD, overweight and obese children constituted 19% of hospitalized and nonhospitalized patients. BMI status did not influence frequency (P=0.90) or duration of hospitalization (P=0.65) for VOC. Obesity was more associated with HbSC than HbSS (P=0.025) genotype. Our study did not demonstrate an association between extremes of BMI of patients and hospitalization for VOC. Considering current trend toward obesity, further prospective and interventional research are required to define the effects of extremes of BMI on pain crises in SCD.
Sergerie, Yan; Boivin, Guy
2008-01-01
Drug-resistant herpes simplex virus type 1 (HSV-1) recombinant strains harboring mutations in the thymidine kinase and/or the DNA polymerase genes were evaluated for their susceptibility to various antivirals in the presence of 25 microg/ml of hydroxyurea (HyU). The latter compound decreased the 50% inhibitory concentrations of acyclovir by 1.5-3.8-fold and that of cidofovir by 2.7-14.4-fold. However, HyU did not affect the susceptibilities of the various recombinant mutants to foscarnet. Hydroxyurea, a ribonucleotide reductase inhibitor, can increase the activity of nucleoside/nucleotide analogues against drug-resistant viruses.
Xu, Yong-Jie; Singh, Amanpreet; Alter, Gerald M
2016-11-01
Hydroxyurea (HU) has been used for the treatment of multiple diseases, such as cancer. The therapeutic effect is generally believed to be due to the suppression of ribonucleotide reductase (RNR), which slows DNA polymerase movement at replication forks and induces an S phase cell cycle arrest in proliferating cells. Although aberrant mitosis and DNA damage generated at collapsed forks are the likely causes of cell death in the mutants with defects in replication stress response, the mechanism underlying the cytotoxicity of HU in wild-type cells remains poorly understood. While screening for new fission yeast mutants that are sensitive to replication stress, we identified a novel mutation in the erg11 gene encoding the enzyme sterol-14α-demethylase in the ergosterol biosynthesis pathway that dramatically sensitizes the cells to chronic HU treatment. Surprisingly, HU mainly arrests the erg11 mutant cells in cytokinesis, not in S phase. Unlike the reversible S phase arrest in wild-type cells, the cytokinesis arrest induced by HU is relatively stable and occurs at low doses of the drug, which likely explains the remarkable sensitivity of the mutant to HU. We also show that the mutation causes sterol deficiency, which may predispose the cells to the cytokinesis arrest and lead to cell death. We hypothesize that in addition to the RNR, HU may have a secondary unknown target(s) inside cells. Identification of such a target(s) may greatly improve the chemotherapies that employ HU or help to expand the clinical usage of this drug for additional pathological conditions. Copyright © 2016 by the Genetics Society of America.
Developmental Function in Toddlers With Sickle Cell Anemia
Elkin, T. David; Brown, R. Clark; Glass, Penny; Rana, Sohail; Casella, James F.; Kalpatthi, Ram V.; Pavlakis, Steven; Mi, Zhibao; Wang, Winfred C.
2013-01-01
BACKGROUND: Neurocognitive impairment occurs in children and adults with sickle cell anemia, but little is known about neurodevelopment in very young children. We examined the neurodevelopmental status of infants participating in the Pediatric Hydroxyurea Phase III Clinical Trial (Baby Hug) to determine relationships with age, cerebral blood flow velocity, and hemoglobin concentration. METHODS: Standardized measures of infant neurodevelopment were administered to 193 infants with hemoglobin SS or hemoglobin S-β0 thalassemia between 7 and 18 months of age at the time of their baseline evaluation. Associations between neurodevelopmental scores and age, family income, parent education, hemoglobin concentration, and transcranial Doppler velocity were examined. RESULTS: Mean functioning on the baseline neurodevelopment scales was in the average range. There were no mental development scores <70 (impaired); 22 children had scores in the clinically significant range, 11 with impaired psychomotor scores and 11 with problematic behavior rating scores. Significantly poorer performance was observed with older age at baseline. Behavior rating scores were an average of 2.82 percentile points lower per month of age, with similar patterns observed with parent report using adaptive behavior scales. Parent-reported functional abilities and hemoglobin were negatively associated with higher transcranial Doppler velocities. CONCLUSIONS: Whereas overall functioning was in the normal range, behavioral and adaptive function was poorer with older age, even in this very young group of children. Explanatory mechanisms for this association between poorer developmental function and older age need to be identified. PMID:23296434
Treliński, Jacek; Okońska, Marta; Robak, Marta; Chojnowski, Krzysztof
2016-03-01
Patients with essential thrombocythemia suffer from thrombotic complications that are the main source of mortality. Due to its complex pathogenesis, no existing single laboratory method is able to identify the patients at highest risk for developing thrombosis. Twenty patients with essential thrombocythemia at diagnosis, 15 healthy volunteers and 20 patients treated with hydroxyurea were compared with regard to certain rotation thromboelastometry parameters. Clotting time (CT), clot formation time (CFT), α-angle, and maximum clot firmness (MCF) were assessed by using the INTEM, EXTEM, FIBTEM, and NATEM tests. Patients with essential thrombocythemia at diagnosis demonstrated significantly higher mean platelet count and markedly lower mean red blood count than controls. CT and CFT readings were found to be markedly lower in essential thrombocythemia patients at diagnosis than in the control group according to the EXTEM test. Patients at diagnosis had markedly lower CT values (EXTEM, FIBTEM) than patients on hydroxyurea therapy. Alpha angle values were markedly higher in essential thrombocythemia patients at diagnosis than in controls, according to the EXTEM, FIBTEM and NATEM tests. MCF readings were significantly higher in essential thrombocythemia patients at diagnosis than in controls according to EXTEM, INTEM, FIBTEM, and NATEM tests. Patients on hydroxyurea therapy had markedly lower MCF values according to EXTEM test than patients at diagnosis. Patients with essential thrombocythemia demonstrate a prothrombotic state at the time of diagnosis, which is reflected in changes by certain rotation thromboelastometry parameters. The hydroxyurea therapy induces downregulation of the prothrombotic features seen in essential thrombocythemia patients at diagnosis.
MOF Suppresses Replication Stress and Contributes to Resolution of Stalled Replication Forks.
Singh, Dharmendra Kumar; Pandita, Raj K; Singh, Mayank; Chakraborty, Sharmistha; Hambarde, Shashank; Ramnarain, Deepti; Charaka, Vijaya; Ahmed, Kazi Mokim; Hunt, Clayton R; Pandita, Tej K
2018-03-15
The human MOF (hMOF) protein belongs to the MYST family of histone acetyltransferases and plays a critical role in transcription and the DNA damage response. MOF is essential for cell proliferation; however, its role during replication and replicative stress is unknown. Here we demonstrate that cells depleted of MOF and under replicative stress induced by cisplatin, hydroxyurea, or camptothecin have reduced survival, a higher frequency of S-phase-specific chromosome damage, and increased R-loop formation. MOF depletion decreased replication fork speed and, when combined with replicative stress, also increased stalled replication forks as well as new origin firing. MOF interacted with PCNA, a key coordinator of replication and repair machinery at replication forks, and affected its ubiquitination and recruitment to the DNA damage site. Depletion of MOF, therefore, compromised the DNA damage repair response as evidenced by decreased Mre11, RPA70, Rad51, and PCNA focus formation, reduced DNA end resection, and decreased CHK1 phosphorylation in cells after exposure to hydroxyurea or cisplatin. These results support the argument that MOF plays an important role in suppressing replication stress induced by genotoxic agents at several stages during the DNA damage response. Copyright © 2018 American Society for Microbiology.
The subunits of the S-phase checkpoint complex Mrc1/Tof1/Csm3: dynamics and interdependence
2014-01-01
Background The S-phase checkpoint aims to prevent cells from generation of extensive single-stranded DNA that predisposes to genome instability. The S. cerevisiae complex Tof1/Csm3/Mrc1 acts to restrain the replicative MCM helicase when DNA synthesis is prohibited. Keeping the replication machinery intact allows restart of the replication fork when the block is relieved. Although the subunits of the Tof1/Csm3/Mrc1 complex are well studied, the impact of every single subunit on the triple complex formation and function needs to be established. Findings This work studies the cellular localization and the chromatin binding of GFP-tagged subunits when the complex is intact and when a subunit is missing. We demonstrate that the complex is formed in cell nucleus, not the cytoplasm, as Tof1, Csm3 and Mrc1 enter the nucleus independently from one another. Via in situ chromatin binding assay we show that a Tof1-Csm3 dimer formation and chromatin binding is required to ensure the attachment of Mrc1 to chromatin. Our study indicates that the translocation into the nucleus is not the process to regulate the timing of chromatin association of Mrc1. We also studied the nuclear behavior of Mrc1 subunit in the process of adaptation to the presence hydroxyurea. Our results indicate that after prolonged HU incubation, cells bypass the S-phase checkpoint and proceed throughout the cell cycle. This process is accompanied by Mrc1 chromatin detachment and Rad53 dephosphorylation. Conclusions In S. cerevisiae the subunits of the S-phase checkpoint complex Mrc1/Tof1/Csm3 independently enter the cell nucleus, where a Tof1-Csm3 dimer is formed to ensure the chromatin binding of Mrc1 and favor DNA replication and S-phase checkpoint fork arrest. In the process of adaptation to the presence of hydroxyurea Mrc1 is detached from chromatin and Rad53 checkpoint activity is diminished in order to allow S-phase checkpoint escape and completion of the cell cycle. PMID:25379053
The subunits of the S-phase checkpoint complex Mrc1/Tof1/Csm3: dynamics and interdependence.
Uzunova, Sonya Dimitrova; Zarkov, Alexander Stefanov; Ivanova, Anna Marianova; Stoynov, Stoyno Stefanov; Nedelcheva-Veleva, Marina Nedelcheva
2014-01-01
The S-phase checkpoint aims to prevent cells from generation of extensive single-stranded DNA that predisposes to genome instability. The S. cerevisiae complex Tof1/Csm3/Mrc1 acts to restrain the replicative MCM helicase when DNA synthesis is prohibited. Keeping the replication machinery intact allows restart of the replication fork when the block is relieved. Although the subunits of the Tof1/Csm3/Mrc1 complex are well studied, the impact of every single subunit on the triple complex formation and function needs to be established. This work studies the cellular localization and the chromatin binding of GFP-tagged subunits when the complex is intact and when a subunit is missing. We demonstrate that the complex is formed in cell nucleus, not the cytoplasm, as Tof1, Csm3 and Mrc1 enter the nucleus independently from one another. Via in situ chromatin binding assay we show that a Tof1-Csm3 dimer formation and chromatin binding is required to ensure the attachment of Mrc1 to chromatin. Our study indicates that the translocation into the nucleus is not the process to regulate the timing of chromatin association of Mrc1. We also studied the nuclear behavior of Mrc1 subunit in the process of adaptation to the presence hydroxyurea. Our results indicate that after prolonged HU incubation, cells bypass the S-phase checkpoint and proceed throughout the cell cycle. This process is accompanied by Mrc1 chromatin detachment and Rad53 dephosphorylation. In S. cerevisiae the subunits of the S-phase checkpoint complex Mrc1/Tof1/Csm3 independently enter the cell nucleus, where a Tof1-Csm3 dimer is formed to ensure the chromatin binding of Mrc1 and favor DNA replication and S-phase checkpoint fork arrest. In the process of adaptation to the presence of hydroxyurea Mrc1 is detached from chromatin and Rad53 checkpoint activity is diminished in order to allow S-phase checkpoint escape and completion of the cell cycle.
Alpha-thalassaemia and response to hydroxyurea in sickle cell anaemia.
Darbari, Deepika S; Nouraie, Mehdi; Taylor, James G; Brugnara, Carlo; Castro, Oswaldo; Ballas, Samir K
2014-04-01
Hydroxyurea (HU) reduces vaso-occlusive crises (VOC) and other complications of sickle cell anaemia (SCA). Alpha-thalassaemia is a known modifier of SCA. Studies on the efficacy of HU in SCA patients with α-thalassaemia have yielded varying results. To determine the effect of α-thalassaemia in response to HU therapy in the Multicenter Study of Hydroxyurea (MSH) cohort. We compared the laboratory parameters and VOC incidence in the MSH cohort stratified by the presence or the absence of α-thalassaemia. Hydroxyurea showed significant (P = 0.001 for all baseline vs. follow-up comparisons) treatment effect on red cell indices irrespective of α-globin gene deletion. The magnitude of the HU-related changes was similar for mean corpuscular volume (MCV) (no α-thalassaemia 13 fl and α-thalassaemia 13 fl) and mean corpuscular haemoglobin (MCH) (no α-thalassaemia 4 pg and α-thalassaemia 4 pg) in both groups. Foetal haemoglobin (HbF) and F-cells also increased significantly with HU treatment in both groups. Total haemoglobin increased after HU treatment in both groups, but the increase was smaller and not statistically significant in patients with α-thalassaemia. In contrast, HU-related reduction in VOCs was more pronounced in patients with α-thalassaemia (VOC incidence rate ratio HU/placebo: 0.63 for α-thalassaemia and 0.54 for no α-thalassaemia (P for interaction 0.003). Hydroxyurea decreases VOCs in SCA patients with and without α-thalassaemia, and the degree of VOC reduction was more pronounced in the patients with alpha-thalassaemia. Despite the lower baseline values, changes in standard laboratory parameters such as MCV and HbF percent remain useful in monitoring HU therapy in the presence of α-thalassaemia. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Dehury, Snehadhini; Purohit, Prasanta; Patel, Siris; Meher, Satyabrata; Kullu, Bipin Kishore; Sahoo, Lulup Kumar; Patel, Nayan Kumar; Mohapatra, Alok Kumar; Das, Kishalaya; Patel, Dilip Kumar
2015-06-01
Despite compelling evidence that hydroxyurea is safe and effective in sickle cell disease, it is prescribed sparingly due to several barriers like knowledge gaps in certain genotypes, apprehension about its safety and toxicity, and limited resources. We undertook this study to find out the efficacy and safety of HU in patients with HbSβ(+) -thalassemia with IVS1-5(G→C) mutation. We registered 318 patients with HbSβ(+) -thalassemia with IVS1-5(G→C) mutation. Of these, 203 were enrolled for hydroxyurea treatment at a low and fixed dose of 10 mg/kg/day. One hundred four patients (Group-I: 37 children and Group-II: 67 adults) with ≥2 years of hydroxyurea treatment were studied. The rate of vaso-occlusive crises, requirement of blood transfusion and rate of hospitalization reduced from 3 to 0.5, 1 to 0 and 1 to 0 in Group-I and 3 to 0, 1 to 0 and 0.5 to 0 in Group-II respectively after HU therapy (P < 0.0001). %HbF level, hemoglobin, MCV and MCH increased significantly, whereas HbS, WBC, platelet count, serum-bilirubin and LDH levels decreased significantly after HU therapy. It has been observed that along with fairly subtle hematological changes following HU therapy, there was a substantial clinical improvement occurred in these patients. Transient myelotoxicity was observed in 4.8%. There was minimal gonadal toxicity without affecting reproductive function. In view of easy affordability, better acceptability, minimal toxicity, the need of infrequent monitoring and its potential effectiveness, low and fixed dose of hydroxyurea is suitable for treatment of patients with HbSβ(+) -thalassemia in resource poor setting. © 2014 Wiley Periodicals, Inc.
Kehrli, Keffy; Phelps, Michael; Lazarchuk, Pavlo; Chen, Eleanor; Monnat, Ray; Sidorova, Julia M
2016-11-18
The WRN helicase/exonuclease is mutated in Werner syndrome of genomic instability and premature aging. WRN-depleted fibroblasts, although remaining largely viable, have a reduced capacity to maintain replication forks active during a transient hydroxyurea-induced arrest. A strand exchange protein, RAD51, is also required for replication fork maintenance, and here we show that recruitment of RAD51 to stalled forks is reduced in the absence of WRN. We performed a siRNA screen for genes that are required for viability of WRN-depleted cells after hydroxyurea treatment, and identified HDAC1, a member of the class I histone deacetylase family. One of the functions of HDAC1, which it performs together with a close homolog HDAC2, is deacetylation of new histone H4 deposited at replication forks. We show that HDAC1 depletion exacerbates defects in fork reactivation and progression after hydroxyurea treatment observed in WRN- or RAD51-deficient cells. The additive WRN, HDAC1 loss-of-function phenotype is also observed with a catalytic mutant of HDAC1; however, it does not correlate with changes in histone H4 deacetylation at replication forks. On the other hand, inhibition of histone deacetylation by an inhibitor specific to HDACs 1-3, CI-994, correlates with increased processing of newly synthesized DNA strands in hydroxyurea-stalled forks. WRN co-precipitates with HDAC1 and HDAC2. Taken together, our findings indicate that WRN interacts with HDACs 1 and 2 to facilitate activity of stalled replication forks under conditions of replication stress. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.
Chalikiopoulou, Constantina; Tavianatou, Anastasia-Gerasimoula; Sgourou, Argyro; Kourakli, Alexandra; Kelepouri, Dimitra; Chrysanthakopoulou, Maria; Kanelaki, Vasiliki-Kaliopi; Mourdoukoutas, Evangelos; Siamoglou, Stavroula; John, Anne; Symeonidis, Argyris; Ali, Bassam R; Katsila, Theodora; Papachatzopoulou, Adamantia; Patrinos, George P
2016-03-01
Hemoglobinopathies exhibit a remarkable phenotypic diversity that restricts any safe association between molecular pathology and clinical outcomes. Herein, we explored the role of genes involved in the nitric oxide biosynthesis and signaling pathway, implicated in the increase of fetal hemoglobin levels and response to hydroxyurea treatment, in 119 Hellenic patients with β-type hemoglobinopathies. We show that two ASS1 genomic variants (namely, rs10901080 and rs10793902) can serve as pharmacogenomic biomarkers to predict hydroxyurea treatment efficacy in sickle cell disease/β-thalassemia compound heterozygous patients. These markers may exert their effect by inducing nitric oxide biosynthesis, either via altering splicing and/or miRNA binding, as predicted by in silico analysis, and ultimately, increase γ-globin levels, via guanylyl cyclase targeting.
Hanessian, Stephen; Vinci, Valerio; Auzzas, Luciana; Marzi, Mauro; Giannini, Giuseppe
2006-09-15
Analogues of suberoylanilide hydroxamic acid (SAHA) were prepared by replacing the Zn-binding group with squaric acid, N-hydroxyurea, and 4-hydroxymethyl oxazoline units, also varying the length of the aliphatic chain. No inhibitory activity on HDAC was observed below 1.0 microM and no cytotoxic activity on different tumor cell lines was seen below 20.0 microM.
A Case of Recurrent Anaplastic Meningioma of the Skull Base with Radiologic Response to Hydroxyurea
Gurberg, Joshua; Bouganim, Nathaniel; Shenouda, George; Zeitouni, Anthony
2014-01-01
Anaplastic meningiomas are rare and aggressive tumors with a high propensity for local recurrence. Surgical resection and postoperative radiotherapy are the standard of care for primary disease and local recurrences. Refractory disease is managed with chemotherapy with limited success. A highly efficacious, well-tolerated chemotherapeutic agent has yet to be found for this disease entity. Hydroxyurea is currently receiving renewed attention because of its efficacy in inducing apoptosis of meningioma cells in vitro and its favorable side-effect profile. Thus far, in humans, this agent has only induced stable disease. We describe the first patient showing a near complete/partial clinical and radiological regression after 5 months of 25 mg/kg of hydroxyurea once daily, given within 1 month after stereotactic fractionated reirradiation of a previously irradiated and operated anaplastic meningioma of the skull base. Magnetic resonance imaging showed a significant and sustained response with tumor shrinkage and cavitation. PMID:25083390
Clinical and hematological response to hydroxyurea in a patient with Hb Lepore/beta-thalassemia.
Rigano, P; Manfré, L; La Galla, R; Renda, D; Renda, M C; Calabrese, A; Calzolari, R; Maggio, A
1997-05-01
The possibility of increasing Hb F in vivo using drugs like 5-azacytidine, hydroxyurea, and butyrate has been established. However, in many cases this does not entail an increase in total hemoglobin. We report on a patient with Hb Lepore/beta-thalassemia being treated with hydroxyurea (30 mg/Kg/day) because of the presence of erythroid extramedullary masses with severe neurological abnormalities. During therapy the patient showed a remarkable improvement in neurological signs due to the reduction in extra-medullary masses, a significant increase in both total hemoglobin (from 5.8 to 9.7 g/dl) and Hb F (from 4.9 g/dl to 9.1 g/dl). The marked improvement in hemoglobin level in our patient with Hb Lepore/beta-thalassemia suggests gamma-globin gene activation due to the DNA structure determined by the crossover event.
NASA Astrophysics Data System (ADS)
Prasad, Bhim Bali; Rai, Garima
2013-03-01
In this study, both experimental and theoretical vibrational spectra of template (hydroxyurea, HU), monomer (N-(4,6-bisacryloyl amino-[1,3,5] triazine-2-yl-)-acryl amide, TAT), and HU-TAT complexes were compared and these were respectively found to be in good agreement. Binding energies of HU, when complexed with different monomers, were computed using second order Moller Plesset theory (MP2) at 6-311++G(d,p) level both in the gas as well as solution phases. HU is an antineoplastic agent extensively being used in the treatment of polycythaemia Vera and thrombocythemia. It is also used to reduce the frequency of painful attacks in sickle cell anemia. It has antiretroviral property in disease like AIDS. All spectral characterizations were made using Density Functional Theory (DFT) at B3LYP employing 6-31+g(2d, 2p) basis set. The theoretical values for 13C and 1H NMR chemical shifts were found to be in accordance with the corresponding experimental values. Of all different monomers studied for the synthesis of molecularly imprinted polymer (MIP) systems, the monomer TAT (2 mol) was typically found to have a best binding score requisite for complexation with HU (1 mol) at the ground state.
Hai, Xin; Guo, Meihua; Gao, Chunlu; Zhou, Jin
2017-04-15
Hydroxyurea (HU) has been used in the treatment of chronic myeloid leukaemia (CML) and other myeloproliferative malignancies. Considering patient's wide variation in clinical response to HU, a new and simple liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated to monitor patients' compliance to treatment and investigate the pharmacokinetics of HU in patients with CML. Stable isotope labeled HU- 13 C 1 , 15 N 2 was used as internal standard. Plasma samples were treated with acetonitrile to precipitate protein. The supernatant was injected directly without derivatization and separated on a hydrophilic interaction liquid chromatography column. HU was quantitatively analyzed with a mobile phase of acetonitrile-1.5mM ammonium formate (90:10, V:V) within 3min. The proposed method provided a linearity range of 1-200μg/mL. The coefficients of variation for intra- and inter-day precision were less than 2.07% and 4.28%, respectively, while the accuracy (bias) was in the range of -3.77 to 2.96%. This method was satisfactorily applied to the determination of HU in two patients with CML. It is suitable for supporting pharmacokinetic studies and clinical therapeutic monitoring. Copyright © 2017 Elsevier B.V. All rights reserved.
Determination of hydroxyurea in human plasma by HPLC-UV using derivatization with xanthydrol.
Legrand, Tiphaine; Rakotoson, Marie-Georgine; Galactéros, Frédéric; Bartolucci, Pablo; Hulin, Anne
2017-10-01
A simple and rapid high performance liquid chromatography (HPLC) method using ultraviolet (UV) detection was developed to determine hydroxyurea (HU) concentration in plasma sample after derivatization with xanthydrol. Two hundred microliters samples were spiked with methylurea (MeU) as internal standard and proteins were precipitated by adding methanol. Derivatization of HU and MeU was immediately performed by adding 0.02M xanthydrol and 1.5M HCl in order to obtain xanthyl-derivatives of HU and MeU that can be further separated using HPLC and quantified using UV detection at 240nm. Separation was achieved using a C18 column with a mobile phase composed of 20mM ammonium acetate and acetonitrile in gradient elution mode at a flow rate of 1mL/min. The total analysis time did not exceed 18min. The method was found linear from 5 to 400μM and all validation parameters fulfilled the international requirements. Between- and within-run accuracy error ranged from -4.7% to 3.2% and precision was lower than 12.8%. This simple method requires small volume samples and can be easily implemented in most clinical laboratories to develop pharmacokinetics studies of HU and to promote its therapeutic monitoring. Copyright © 2017 Elsevier B.V. All rights reserved.
Inoue, Susumu; Kodjebacheva, Gergana; Scherrer, Tammy; Rice, Gary; Grigorian, Matthew; Blankenship, Jeremy; Onwuzurike, Nkechi
2016-08-01
Adherence to hydroxyurea (HU) is a significant modifying factor in sickle cell vaso-occlusive pain. We conducted a study using an electronic medication container-monitor-reminder device (GlowCap™) to track adherence and determine whether use of this device affected rates of HU adherence. Subjects were regular attendees to our clinic. They were given a 37-item questionnaire and were asked to use a GlowCap containing HU. When the device cap is opened, it makes a remote "medication taken" record. The device also provides usage reminder in the form of lights and alarm sounds if the cap opening is delayed. Nineteen subjects participated in the survey, and 17 in the intervention phase. Of the 17, 12 had reliable adherence data. Seventeen caregivers of patients and two patients completed the survey. Two most common barriers to adherence identified were lack of reminders and absence of medicine home delivery. The intervention component of this study, which used both the electronic (GlowCap) method and medication possession ratio showed that the median adherence rate for the 12 patients evaluated was 85 %. The GlowCap device accurately kept a record of adherence rates. This device may be an effective tool for increasing HU medication adherence.
Feng, Wenyi; Bachant, Jeff; Collingwood, David; Raghuraman, M K; Brewer, Bonita J
2009-12-01
Yeast replication checkpoint mutants lose viability following transient exposure to hydroxyurea, a replication-impeding drug. In an effort to understand the basis for this lethality, we discovered that different events are responsible for inviability in checkpoint-deficient cells harboring mutations in the mec1 and rad53 genes. By monitoring genomewide replication dynamics of cells exposed to hydroxyurea, we show that cells with a checkpoint deficient allele of RAD53, rad53K227A, fail to duplicate centromeres. Following removal of the drug, however, rad53K227A cells recover substantial DNA replication, including replication through centromeres. Despite this recovery, the rad53K227A mutant fails to achieve biorientation of sister centromeres during recovery from hydroxyurea, leading to secondary activation of the spindle assembly checkpoint (SAC), aneuploidy, and lethal chromosome segregation errors. We demonstrate that cell lethality from this segregation defect could be partially remedied by reinforcing bipolar attachment. In contrast, cells with the mec1-1 sml1-1 mutations suffer from severely impaired replication resumption upon removal of hydroxyurea. mec1-1 sml1-1 cells can, however, duplicate at least some of their centromeres and achieve bipolar attachment, leading to abortive segregation and fragmentation of incompletely replicated chromosomes. Our results highlight the importance of replicating yeast centromeres early and reveal different mechanisms of cell death due to differences in replication fork progression.
Yilmaz, Baris; Teksoz, Serap; Kilcar, Ayfer Yurt; Ucar, Eser; Ichedef, Cigdem; Medine, Emin Ilker; Ari, Kadir
2016-02-01
The aim of current study is to examine hydroxyurea (HU), which is an antineoplastic drug used for the treatment of leukemia, sickle-cell disease, HIV, psoriasis, thrombocythemia, and various neoplastic diseases in two aspects. The active ingredient hydroxyurea was obtained by purification of the capsule form drug, commercially named as HYDREA. Then, [(99m)Tc(CO)3](+)core radiolabeling with HU was performed as first aspect. Quality control studies of (99m)Tc(CO)3-HU complex were performed by thin-layer radiochromatography and high-performance liquid radiochromatography methods. The results demonstrated that the radiolabeling yield was quite high (98.43% ± 2.29%). Also, (99m)Tc(CO)3-HU complex has good stability during the 24-hour period. Biological behavior of (99m)Tc(CO)3-HU complex is evaluated by biodistribution studies on Wistar Albino rats. Fluorescein isothiocyanate (FITC) labeling of HU was performed as second aspect. Fluorometric evaluation of binding efficacy and fluorescence imaging studies on MCF7 and Hela cell lines were carried out. It was thought that the knowledge achieved in this study would contribute to using (99m)Tc(CO)3-HU complex as an imaging agent, which inhibits the DNA synthesis selectively, by inhibiting ribonucleotide reductase enzyme. It was observed that FITC-HU has noteworthy incorporation on both cell lines.
Badawy, Sherif M; Thompson, Alexis A; Lai, Jin-Shei; Penedo, Frank J; Rychlik, Karen; Liem, Robert I
2017-06-01
Complications related to sickle cell disease (SCD) result in significant declines in health-related quality of life (HRQOL). While hydroxyurea reduces SCD complications, adherence remains suboptimal. The study's objectives were to assess the feasibility of Internet-based electronic assessment of HRQOL in SCD clinic and to examine the relationship between HRQOL and hydroxyurea adherence in adolescents and young adults (AYAs) with SCD. A cross-sectional survey was administered on tablets to 34 AYAs (12-22 years old) in a SCD clinic from January through December 2015. Study measures included Patient Reported Outcomes Measurement Information System (PROMIS ® ) computerized adaptive testing and ©Modified Morisky Adherence Scale 8-items (©MMAS-8). Participants (59% male, 91% Black) had median age of 13.5 (range 12-18) years. Ninety-one percent completed PROMIS® measures electronically in the clinic, meeting our feasibility criterion of ≥85% completion rate. ©MMAS-8 scores positively correlated with fetal hemoglobin (HbF) (r s = 0.34, P = 0.04) and mean corpuscular volume (MCV) (r s = 0.42, P = 0.01) and inversely correlated with fatigue (r s = -0.45, P = 0.01), depression (r s = -0.3, P = 0.08), and social isolation (r s = -0.78, P = 0.02). Low ©MMAS-8 scores, indicating poor adherence, were associated with worse fatigue (P = 0.001) and trended toward significance for pain (P = 0.07) and depression (P = 0.06). Homozygous hemoglobin S disease patients with low HbF (<16%) had worse social isolation (P = 0.04) and those with low MCV (<102 fl) reported worse fatigue (P = 0.001), pain (P = 0.01), mobility (P = 0.01), and social isolation (P = 0.04). HRQOL assessment in the SCD clinic is feasible. SCD patients with low hydroxyurea adherence and/or low HbF or MCV levels had worse HRQOL scores, particularly fatigue. Future prospective studies examining the relationship between HRQOL and hydroxyurea adherence are warranted. © 2016 Wiley Periodicals, Inc.
Rybaczek, Dorota; Bodys, Aleksandra; Maszewski, Janusz
2007-09-01
Immunocytochemistry using alpha-phospho-H2AX antibodies shows that hydroxyurea (HU), an inhibitor of ribonucleotide reductase, and aphidicolin (APH), an inhibitor of DNA-polymerases alpha and delta, may promote formation of phospho-H2AX foci in late S/G2-phase cells in root meristems of Vicia faba. Although fluorescent foci spread throughout the whole area of nucleoplasm, large phospho-H2AX aggregates in HU-treated cells allocate mainly in perinucleolar regions. A strong tendency of ATR/ATM-dependent phospho-Chk1S317 kinase to focus in analogous compartments, as opposed to phospho-Chk2T68 and to both effector kinases in APH-treated cells, may suggest that selected elements of the intra-S-phase cell cycle checkpoints share overlapping locations with DNA repair factors known to concentrate in phospho-H2AX aggregates. APH-induced phosphorylation of H2AX exhibits little or no overlap with the areas positioned close to nucleoli. Following G2-M transition of the HU- and APH-pretreated cells, altered chromatin structures are still discernible as large phospho-H2AX foci in the vicinity of chromosomes. Both in HU- and APH-treated roots, immunofluorescence analysis revealed a dominant fraction of small foci and a less frequent population of large phospho-H2AX aggregates, similar to those observed in animal cells exposed to ionizing radiation. The extent of H2AX phosphorylation has been found considerably reduced in root meristem cells treated with HU and caffeine. The frequencies of phospho-H2AX foci observed during mitosis and caffeine-mediated premature chromosome condensation (PCC) suggest that there may be functional links between the checkpoint mechanisms that control genome integrity and those activities which operate throughout the unperturbed mitosis in plants.
Severe excessive daytime sleepiness induced by hydroxyurea.
Revol, Bruno; Joyeux-Faure, Marie; Albahary, Marie-Victoire; Gressin, Remy; Mallaret, Michel; Pepin, Jean-Louis; Launois, Sandrine H
2017-06-01
Excessive daytime sleepiness (EDS) has been reported with many drugs, either as an extension of a hypnotic effect (e.g. central nervous system depressants) or as an idiosyncratic response of the patient. Here, we report unexpected and severe subjective and objective EDS induced by hydroxyurea therapy, with a favorable outcome after withdrawal. Clinical history, sleep log, polysomnography, and multiple sleep latency tests confirming the absence of other EDS causes are presented. © 2016 Société Française de Pharmacologie et de Thérapeutique.
Abdel Karim, K.; El Shehaby, A.; Emad, R.; Reda, W.; El Mahdy, M.; Ghali, R.; Nabeel, A.
2016-01-01
Abstract Objective: The use of gamma knife radiosurgery in the treatment of atypical (WHO grade II) meningiomas has been reported in the past with highly variable degrees of success. The use of hydroxyurea as a radiation sensitizer as well as salvage chemotherapy in cancer patients is well established and was also used for treatment of recurrent and malignant meningiomas. In this study we investigated the effect of hydroxyurea administration after gamma knife radiosurgery for atypical (grade II) meningiomas on local tumor control and patient survival. Patients and methods: Between November 2008 and April 2014, thirty-five patients with pathologically proven atypical meningiomas were treated by gamma knife radiosurgery. We excluded patients who had received previous external beam radiotherapy. Twenty-three patients were given hydroxyurea after gamma knife treatment. The rest of the patients refused to take the treatment or were incompliant (were not included in the study). Of these 23, nineteen patients harboring 20 tumors were available for radiological and clinical follow up for a minimum of 2 years. Four patients were lost from follow up. Twenty tumors underwent 26 gamma knife procedures. Five tumors underwent staged treatment. The tumor volume was 0.6–38.3 cc (median 12.7 cc). The prescription dose/session ranged from 10 to 16 Gy (mean 14 Gy). The patients received a course of hydroxyurea (1000 mg/day) for one year after gamma knife treatment. The mean follow up period was 43 months (14–76 months). Results: Tumor control was achieved in 18 out of 20 tumors where 15 tumors shrank and 3 tumors remained stable with a tumor control rate of 90%. Tumor progression occurred in 2 patients (at 14 and 15 months). Transient edema was observed with 6 tumors which was temporary, and no G3 or G4 myelosuppression were recorded. Two patients died from progression of other tumors not included in the study after 3 and 6 years. Distant tumor progression (in another intracranial location or outside the radiation field) was observed in 5 patients. In 3 patients new tumors developed at the edge of previous craniotomy, in one patient tumor progression occurred after receiving radiosurgery alone for another lesion after the end of adjuvant treatment and in one patient progression occurred in an untreated tumor that was under observation. The actuarial progression free survival and overall survival at 3 years were 89.5% and 94% respectively. Conclusion: Preliminary results suggest good tumor control and shrinkage of atypical (grade II) meningiomas treated with Gamma Knife radiosurgery followed by one year of adjuvant hydroxyurea. Further larger randomized and double-arm studies are required to confirm the potential role of hydroxyurea in those tumors.
Arnaud, Cécile; Kamdem, Annie; Hau, Isabelle; Lelong, Françoise; Epaud, Ralph; Pondarré, Corinne; Pissard, Serge
2018-01-01
Sickle cell anemia (SCA), albeit monogenic, has heterogeneous phenotypic expression, mainly related to the level of hemoglobin F (HbF). No large cohort studies have ever compared biological parameters in patients with major β-globin haplotypes; ie, Senegal (SEN), Benin (BEN), and Bantu/Central African Republic (CAR). The aim of this study was to evaluate the biological impact of α genes, β haplotypes, and glucose-6-phosphate dehydrogenase (G6PD) activity at baseline and with hydroxyurea (HU). Homozygous HbS patients from the Créteil pediatric cohort with available α-gene and β-haplotype data were included (n = 580; 301 females and 279 males) in this retrospective study. Homozygous β-haplotype patients represented 74% of cases (37.4% CAR/CAR, 24.3% BEN/BEN, and 12.1% SEN/SEN). HU was given to 168 cohort SCA children. Hematological parameters were recorded when HbF was maximal, and changes (ΔHU-T0) were calculated. At baseline, CAR-haplotype and α-gene numbers were independently and negatively correlated with Hb and positively correlated with lactate dehydrogenase. HbF was negatively correlated with CAR-haplotype numbers and positively with BEN- and SEN-haplotype numbers. The BCL11A/rs1427407 “T” allele, which is favorable for HbF expression, was positively correlated with BEN- and negatively correlated with CAR-haplotype numbers. With HU treatment, Δ and HbF values were positively correlated with the BEN-haplotype number. BEN/BEN patients had higher HbF and Hb levels than CAR/CAR and SEN/SEN patients. In conclusion, we show that BEN/BEN patients have the best response on HU and suggest that this could be related to the higher prevalence of the favorable BCL11A/rs1427407/T/allele for HbF expression in these patients. PMID:29555644
Tantawy, Azza Abdel Gawad; Adly, Amira Abdel Moneam; Ismail, Eman Abdel Rahman; Youssef, Omneya Ibrahim; Ali, Mohamed ElSayed
2017-11-01
Endothelial damage has been implicated in the pathogenesis of vascular complications in β-thalassemia intermedia (β-TI). Soluble fms-like tyrosine kinase 1 (sFLT-1) is a member of the vascular endothelial growth factor receptor (VEGFR) family. Soluble fms-like tyrosine kinase 1 is an antiangiogenic protein that induces endothelial dysfunction by adhering to and inhibiting VEGF and placenta growth factor. The aim of this study was to assess the level of sFLT-1 in 35 children and adolescents with β-TI, correlating it with markers of hemolysis and iron overload as well as cardiopulmonary complications. Patients were studied focusing on the history of cardiac disease, splenectomy, transfusion, chelation/hydroxyurea therapy, serum ferritin, and sFLT-1 levels. Echocardiography and measurement of carotid intima-media thickness (CIMT) were done for all participants. Soluble fms-like tyrosine kinase 1 was significantly higher in TI patients compared to the control group (median [interquartile range], 110 [80-155] pg/mL versus 70 [60-90] pg/mL; P < .001). Splenectomized patients and those who had pulmonary hypertension risk or heart disease had higher sFLT-1 levels than those without ( P < .001). The sFLT-1 cutoff value that differentiates patients with and without pulmonary hypertension risk or heart disease was determined. Soluble fms-like tyrosine kinase 1 was lower among patients who received chelation therapy and/or hydroxyurea. Significant positive relations were observed between sFLT-1 and lactate dehydrogenase, serum ferritin, liver iron concentration, tricuspid regurgitant jet velocity, and CIMT. We suggest that sFLT-1 represents a link between angiogenesis, endothelial dysfunction, and subclinical atherosclerosis. Measurement of sFLT-1 as a marker of vascular dysfunction in β-TI may provide utility for early identification of patients at increased risk of cardiopulmonary complications.
Essential thrombocythaemia in two dogs.
Favier, R P; van Leeuwen, M; Teske, E
2004-06-01
In this report two dogs with essential thrombocythaemia (ET) are described. Both dogs were presented more or less at the same time with a combination of reduced exercise tolerance and pale mucous membranes without any report of blood loss. Moderate-to-severe, Coomb's-negative anaemia and thrombocytosis (> 1249 x 10'/l) were present. In addition, the peripheral blood smear revealed the presence of basophilia and large numbers of abnormally shaped megakaryocytes in the bone marrow of both dogs. Treatment with vincristine (0.7 mg/m2 once intravenously) and hydroxyurea (500 mg/m2 p.o. per day) was started. Because of insufficient response to treatment after 3 weeks, the dosage of hydroxyurea was increased in both dogs to 2000 mg/m2 p.o. per day. The dogs deteriorated further, however, and were euthanized at 6 weeks after the start of treatment. Blood examination revealed pancytopenia in both dogs, most likely due to the myelosuppressive effects of high-dose hydroxyurea. A survey of veterinary literature on ET is presented, including a comparison of ET in humans.
NEK8 regulates DNA damage-induced RAD51 foci formation and replication fork protection
Abeyta, Antonio; Castella, Maria; Jacquemont, Celine; Taniguchi, Toshiyasu
2017-01-01
ABSTRACT Proteins essential for homologous recombination play a pivotal role in the repair of DNA double strand breaks, DNA inter-strand crosslinks and replication fork stability. Defects in homologous recombination also play a critical role in the development of cancer and the sensitivity of these cancers to chemotherapy. RAD51, an essential factor for homologous recombination and replication fork protection, accumulates and forms immunocytochemically detectable nuclear foci at sites of DNA damage. To identify kinases that may regulate RAD51 localization to sites of DNA damage, we performed a human kinome siRNA library screen, using DNA damage-induced RAD51 foci formation as readout. We found that NEK8, a NIMA family kinase member, is required for efficient DNA damage-induced RAD51 foci formation. Interestingly, knockout of Nek8 in murine embryonic fibroblasts led to cellular sensitivity to the replication inhibitor, hydroxyurea, and inhibition of the ATR kinase. Furthermore, NEK8 was required for proper replication fork protection following replication stall with hydroxyurea. Loading of RAD51 to chromatin was decreased in NEK8-depleted cells and Nek8-knockout cells. Single-molecule DNA fiber analyses revealed that nascent DNA tracts were degraded in the absence of NEK8 following treatment with hydroxyurea. Consistent with this, Nek8-knockout cells showed increased chromosome breaks following treatment with hydroxyurea. Thus, NEK8 plays a critical role in replication fork stability through its regulation of the DNA repair and replication fork protection protein RAD51. PMID:27892797
NEK8 regulates DNA damage-induced RAD51 foci formation and replication fork protection.
Abeyta, Antonio; Castella, Maria; Jacquemont, Celine; Taniguchi, Toshiyasu
2017-02-16
Proteins essential for homologous recombination play a pivotal role in the repair of DNA double strand breaks, DNA inter-strand crosslinks and replication fork stability. Defects in homologous recombination also play a critical role in the development of cancer and the sensitivity of these cancers to chemotherapy. RAD51, an essential factor for homologous recombination and replication fork protection, accumulates and forms immunocytochemically detectable nuclear foci at sites of DNA damage. To identify kinases that may regulate RAD51 localization to sites of DNA damage, we performed a human kinome siRNA library screen, using DNA damage-induced RAD51 foci formation as readout. We found that NEK8, a NIMA family kinase member, is required for efficient DNA damage-induced RAD51 foci formation. Interestingly, knockout of Nek8 in murine embryonic fibroblasts led to cellular sensitivity to the replication inhibitor, hydroxyurea, and inhibition of the ATR kinase. Furthermore, NEK8 was required for proper replication fork protection following replication stall with hydroxyurea. Loading of RAD51 to chromatin was decreased in NEK8-depleted cells and Nek8-knockout cells. Single-molecule DNA fiber analyses revealed that nascent DNA tracts were degraded in the absence of NEK8 following treatment with hydroxyurea. Consistent with this, Nek8-knockout cells showed increased chromosome breaks following treatment with hydroxyurea. Thus, NEK8 plays a critical role in replication fork stability through its regulation of the DNA repair and replication fork protection protein RAD51.
Chronic transfusion practice for children with sickle cell anaemia and stroke.
Aygun, Banu; McMurray, Marsha A; Schultz, William H; Kwiatkowski, Janet L; Hilliard, Lee; Alvarez, Ofelia; Heeney, Matthew; Kalinyak, Karen; Lee, Margaret T; Miller, Scott; Helms, Ronald W; Ware, Russell E
2009-05-01
Chronic transfusions to maintain haemoglobin S (HbS) < or =30% are the mainstay of treatment for children with sickle cell anaemia (SCA) and previous stroke. This HbS target is often hard to maintain, however, and values achieved in current practice are unknown. In preparation for the Phase III Stroke With Transfusions Changing to Hydroxyurea (SWiTCH) trial, we collected data on 295 children with SCA and stroke who received transfusions at 23 institutions. The overall average pre-transfusion %HbS was 35 +/- 11% (institutional range 22-51%). Receiving scheduled transfusions on time was the most predictive variable for maintaining HbS at the < or =30% goal.
Hydroxyurea derivatives of irofulven with improved antitumor efficacy.
Staake, Michael D; Kashinatham, Alisala; McMorris, Trevor C; Estes, Leita A; Kelner, Michael J
2016-04-01
Irofulven is a semi-synthetic derivative of Illudin S, a toxic sesquiterpene isolated from the mushroom Omphalotus illudens. Irofulven has displayed significant antitumor activity in various clinical trials but displayed a limited therapeutic index. A new derivative of irofulven was prepared by reacting hydroxyurea with irofulven under acidic conditions. Acetylation of this new compound with acetic anhydride produced a second derivative. Both of these new derivatives displayed significant antitumor activity in vitro and in vivo comparable to or exceeding that of irofulven. Copyright © 2016 Elsevier Ltd. All rights reserved.
Motovali-Bashi, Majid; Ghasemi, Tayyebeh
2015-01-01
β-thalassemia is the most common monogenic disorder in human. The (C-->T) polymorphism at -158 upstream region of the γG-globin gene and pharmacological factors such as hydroxyurea have been reported to influence γ-globin gene expression and the severity of clinical symptoms of β-thalassemia. In the present study, 51 β-thalassemia intermediate patients were studied. Xmn1γG polymorphism genotype was determined using Tetra-Primer ARMS-PCR technique. Hemoglobin (Hb) and fetal hemoglobin (HbF) levels were determined by gel electrophoresis. Of 51 patients, 35 (68.6%) patients were heterozygous (CT) and 16 (31.4%) patients were homozygous (CC). Of 30 patients under treatment by hydroxyurea, 20 (66.7%) patients were heterozygous (CT) and 10 (33.3%) patients were homozygous (CC). Our results demonstrated that in the heterozygous (CT) genotype, the Hb (9.58 ± 1.25 gm/dl) and HbF (89.30 ± 21.87) levels were significantly higher in comparison with homozygous (CC) genotype (7.94 ± 1.34 gm/dl and 70.32 ± 40.56, respectively). Furthermore, we observed that after drug usage, the Hb and HbF levels in patients with heterozygous (CT) genotype (0.7 ± 1.26 gm/dl and 5.95 ± 14.8, respectively) raised more in comparison with homozygous (CC) genotype (0.26 ± 1.43 gm/dl and 0.8 ± 1.31, respectively). Hb and HbF levels in the patients carrying T allele are increased significantly, and they also response to hydroxyurea treatment.
Shiba, Hala Fathy; El-Ghamrawy, Mona Kamal; Shaheen, Iman Abd El-Mohsen; Ali, Rasha Abd El-Ghani; Mousa, Somaia Mohammed
2014-01-01
Sickle cell disease (SCD) complications are associated with oxidative stress. Glutathione S-transferases (GSTs) are a group of enzymes that protect against oxidative stress. The aims of this study was to evaluate the prevalence of GSTM1, GSTT1, and GSTP1 gene polymorphisms among homozygous sickle cell anemia patients and to investigate the possible association between the presence of these polymorphisms and SCD severity and complications. Genotyping the polymorphisms in GSTT1 and GSTM1 genes was performed using the multiplex polymerase chain reaction (PCR) method. The GSTP1 ILe105Val polymorphism was determined using PCR-restriction fragment length polymorphism. GSTM1 null genotype was significantly associated with increased risk of severe vaso-occlusive crises (VOC) (odds ratio = 1.52, 95% confidence interval = 0.42-5.56, P = 0.005). We found no significant association between GST genotypes and frequency of sickle cell-related pain, transfusion frequency, disease severity, or hydroxyurea treatment. GSTM1 gene polymorphism may be associated with risk of severe VOC among Egyptian SCD patients.
Sickle cell disease caused by Hb S/Québec-CHORI: treatment with hydroxyurea and response.
Tubman, Venée N; Bennett, Carolyn M; Luo, Hong-yuan; Chui, David H K; Heeney, Matthew M
2007-08-01
Sickle hemoglobin (Hb S;betaGlu 6 Val) is due to an A>T transversion in codon 6 of the beta-globin gene. Other variant hemoglobins mimic Hb A, S, or C on newborn screening and clinical laboratory diagnostic tools, thus making their correct identification potentially difficult. Sickling disorders can result in individuals who are compound heterozygous for beta-globin mutations (e.g., Hb SC, HbSO(Arab)). The authors report a second case of HbS/Québec-CHORI, a severe compound heterozygous sickling disorder and their experience managing this patient with hydroxyurea.
CCCT - NCTN Steering Committees - Pediatric and Adolescent Tumor
The Pediatric and Adolescent Solid Tumor Steering Committee addresses the design, prioritization and evaluation of concepts for large phase 2 and phase 3 clinical trials in extracranial solid tumors of children and youth.
Communication about the Risks and Benefits of Phase I Pediatric Oncology Trials
Hazen, Rebecca A.; Zyzanski, Stephen; Baker, Justin; Drotar, Dennis; Kodish, Eric
2015-01-01
Introduction Phase 1 pediatric oncology trials offer only a small chance of direct benefit and may have significant risks and an impact on quality of life. To date, research has not examined discussions of risks and benefits during informed consent conferences for phase 1 pediatric oncology trials. The objective of the current study was to examine clinician and family communication about risks, benefits, and quality of life during informed consent conferences for phase 1 pediatric oncology trials. Methods Participants included clinician investigators, parents, and children recruited from 6 sites conducting phase 1 pediatric oncology trials. Eighty-five informed consent conferences were observed and audiotaped. Trained coders assessed discussions of risks, benefits, and quality of life. Types of risks discussed were coded (e.g., unanticipated risks, digestive system risks, death). Types of benefits were categorized as therapeutic (e.g. discussion of how participation may or may not directly benefit child), psychological, bridge to future trial, and altruism. Results Risks and benefits were discussed in 95% and 88% of informed consent conferences, respectively. Therapeutic benefit was the most frequently discussed benefit. The impact of trial participation on quality of life was discussed in the majority (88%) of informed consent conferences. Conclusion Therapeutic benefit, risks, and quality of life were frequently discussed. The range of information discussed during informed consent conferences suggests the need for considering a staged process of informed consent for phase 1 pediatric oncology trials. PMID:25638751
Proteomic analysis of the response to cell cycle arrests in human myeloid leukemia cells.
Ly, Tony; Endo, Aki; Lamond, Angus I
2015-01-02
Previously, we analyzed protein abundance changes across a 'minimally perturbed' cell cycle by using centrifugal elutriation to differentially enrich distinct cell cycle phases in human NB4 cells (Ly et al., 2014). In this study, we compare data from elutriated cells with NB4 cells arrested at comparable phases using serum starvation, hydroxyurea, or RO-3306. While elutriated and arrested cells have similar patterns of DNA content and cyclin expression, a large fraction of the proteome changes detected in arrested cells are found to reflect arrest-specific responses (i.e., starvation, DNA damage, CDK1 inhibition), rather than physiological cell cycle regulation. For example, we show most cells arrested in G2 by CDK1 inhibition express abnormally high levels of replication and origin licensing factors and are likely poised for genome re-replication. The protein data are available in the Encyclopedia of Proteome Dynamics (
Lê, Phu Quoc; Gulbis, Béatrice; Dedeken, Laurence; Dupont, Sophie; Vanderfaeillie, Anna; Heijmans, Catherine; Huybrechts, Sophie; Devalck, Christine; Efira, André; Dresse, Marie-Françoise; Rozen, Laurence; Benghiat, Fleur Samantha; Ferster, Alina
2015-11-01
To evaluate the survival of patients with sickle cell disease (SCD) recorded in the Belgian SCD Registry and to assess the impact of disease-modifying treatments (DMT). The Registry created in 2008 included patients of eight centers. All available data in 2008 were retrospectively encoded in the database. After 2008 and until 2012, all data were recorded prospectively for already registered patients as well as newly diagnosed subjects. Data were registered from neonatal screening or from diagnosis (first contact) until last follow-up or death. Data included diagnosis, demography, and outcome data. We collected data from 469 patients over a 5,110 patient years (PY) follow-up period. The global mortality rate was low (0.25/100 PY), although 13 patients died (2.8%) and was similar between children, adolescents (10-18 years), and young adults (P = 0.76). Out of the cohort, 185 patients received hydroxyurea at last follow-up (median duration of treatment: 10.3 years), 90 underwent hematopoietic stem cell transplantation (HSCT), 24 were chronically transfused, and 170 had never had any DMT. Hydroxyurea showed significant benefit on patients outcome as reflected by a lower mortality rate compared to transplanted individuals or people without DMT (0.14, 0.36, and 0.38 per 100 PY, respectively) and by higher Kaplan-Meier estimates of 15 year survival (99.4%) compared to HSCT (93.8%; P = 0.01) or no DMT groups (95.4%; P = 0.04). SCD mortality in Belgium is low with no increase observed in young adults. Patients treated with hydroxyurea demonstrate a significant benefit in survival when compared to those without DMT or transplanted. © 2015 Wiley Periodicals, Inc.
2017-06-01
Vitamin D Deficiency; Stem Cell Transplant Complications; Pediatric Cancer; Blood Disorder; Pediatric Acute Myeloid Leukemia; Pediatric Acute Lymphoid Leukemia; Myelodysplastic Syndromes; Sickle Cell Anemia in Children; Aplastic Anemia; Thalassemia in Children
Polycythemia Vera Management and Challenges in the Community Health Setting
Gerds, Aaron T.; Dao, Kim-Hien
2017-01-01
Patients with polycythemia vera (PV) experience shortened survival, increased risk of thromboembolic and hemorrhagic events, and burdensome symptoms. For all patients with PV, treatment with aspirin and hematocrit control with phlebotomy are recommended. In addition, patients with high-risk status or poor hematocrit control benefit from cytoreductive therapy with hydroxyurea, although approximately 1 in 4 patients develops resistance or intolerance. For patients who are resistant to or intolerant of hydroxyurea, studies have shown that ruxolitinib, a Janus kinase 1/2 inhibitor, provides hematocrit control, reduces spleen size, normalizes blood counts, and improves PV-related symptoms. For many patients, PV is managed in a community health setting, and it is important that community hematologists, oncologists, and internists are familiar with the contemporary management of PV to improve patient outcomes, including management for patients who present with unique health-care needs. This review provides an overview of current treatment options for patients with PV and discusses challenging circumstances encountered by community providers in the management of PV, including symptom assessment, identification of hydroxyurea resistance/intolerance, pregnancy, elective surgeries, concomitant immunosuppressants, and managing patients in areas with limited access to specialized hematologic care. PMID:28095380
A Semi-flexible 64-channel Receive-only Phased Array for Pediatric Body MRI at 3T
Zhang, Tao; Grafendorfer, Thomas; Cheng, Joseph Y.; Ning, Peigang; Rainey, Bob; Giancola, Mark; Ortman, Sarah; Robb, Fraser J.; Calderon, Paul D.; Hargreaves, Brian A.; Lustig, Michael; Scott, Greig C.; Pauly, John M.; Vasanawala, Shreyas S.
2015-01-01
Purpose To design, construct, and validate a semi-flexible 64-channel receive-only phased array for pediatric body MRI at 3T. Methods A 64-channel receive-only phased array was developed and constructed. The designed flexible coil can easily conform to different patient sizes with non-overlapping coil elements in the transverse plane. It can cover a field of view of up to 44 × 28 cm2 and removes the need for coil repositioning for body MRI patients with multiple clinical concerns. The 64-channel coil was compared with a 32-channel standard coil for signal-to-noise ratio (SNR) and parallel imaging performances on different phantoms. With IRB approval and informed consent/assent, the designed coil was validated on 21 consecutive pediatric patients. Results The pediatric coil provided higher SNR than the standard coil on different phantoms, with the averaged SNR gain at least 23% over a depth of 7 cm along the cross-section of phantoms. It also achieved better parallel imaging performance under moderate acceleration factors. Good image quality (average score 4.6 out of 5) was achieved using the developed pediatric coil in the clinical studies. Conclusion A 64-channel semi-flexible receive-only phased array has been developed and validated to facilitate high quality pediatric body MRI at 3T. PMID:26418283
Child neurology: Past, present, and future: part 1: history.
Millichap, John J; Millichap, J Gordon
2009-08-18
The founding period of child neurology occurred in 3 phases: 1) early individual contributory phase, 2) organized training phase, and 3) expansion phase. In the late 19th and early 20th centuries, individuals in pediatrics, neurology, and psychiatry established clinics and made important contributions to the literature on childhood epilepsy, cerebral palsy, and pediatric neurology. The latter half of the 20th century saw the organization of training programs in pediatric neurology, with fellowships supported by the NIH. This development was followed by a rapid expansion in the number of trainees certified in child neurology and their appointment to divisions of neurology in children's hospitals. In recent years, referrals of children with neurologic disorders have increased, and disorders previously managed by pediatricians are often seen in neurology clinics. The era of subspecialization is embraced by the practicing physician. The present day status of pediatric neurology and suggestions for the future development of the specialty are subjects for further discussion.
Johnson, Liza-Marie; Leek, Angela C.; Drotar, Dennis; Noll, Robert B.; Rheingold, Susan R.; Kodish, Eric D.; Baker, Justin N.
2015-01-01
Background It can be difficult to explain pediatric Phase I oncology trials to families of children with refractory cancer. Parents may misunderstand the information presented to them, and physicians may assume that certain topics are covered in the informed consent document and need not be discussed. Communication models can help to ensure effective discussions. Methods Suggestions for improving the informed consent process were first solicited from Phase I study clinicians via questionnaire. Eight parents who had enrolled their child on a Phase I pediatric oncology trial were recruited for an advisory group designed to assess the clinicians’ suggestions and make additional recommendations for improving informed consent for pediatric Phase I trials. Results A Phase I Communication Model was designed to incorporate the suggestions of clinicians and families. It focuses on education of parents/families about Phase I trials at specific time points during a child’s illness, but specifically at the point of relapse. We also present an informative Phase I fact sheet that can be distributed to families. Conclusions Families who will be offered information about a Phase I clinical trial can first receive a standardized fact sheet explaining the general purpose of these early-phase clinical trials. Parental understanding may be further enhanced when oncologists address key themes, beginning at diagnosis and continuing through important decision points during the child’s illness. This model should be prospectively evaluated. PMID:25873253
Catalase and NO CATALASE ACTIVITY1 Promote Autophagy-Dependent Cell Death in Arabidopsis[C][W][OPEN
Hackenberg, Thomas; Juul, Trine; Auzina, Aija; Gwiżdż, Sonia; Małolepszy, Anna; Van Der Kelen, Katrien; Dam, Svend; Bressendorff, Simon; Lorentzen, Andrea; Roepstorff, Peter; Lehmann Nielsen, Kåre; Jørgensen, Jan-Elo; Hofius, Daniel; Breusegem, Frank Van; Petersen, Morten; Andersen, Stig Uggerhøj
2013-01-01
Programmed cell death often depends on generation of reactive oxygen species, which can be detoxified by antioxidative enzymes, including catalases. We previously isolated catalase-deficient mutants (cat2) in a screen for resistance to hydroxyurea-induced cell death. Here, we identify an Arabidopsis thaliana hydroxyurea-resistant autophagy mutant, atg2, which also shows reduced sensitivity to cell death triggered by the bacterial effector avrRpm1. To test if catalase deficiency likewise affected both hydroxyurea and avrRpm1 sensitivity, we selected mutants with extremely low catalase activities and showed that they carried mutations in a gene that we named NO CATALASE ACTIVITY1 (NCA1). nca1 mutants showed severely reduced activities of all three catalase isoforms in Arabidopsis, and loss of NCA1 function led to strong suppression of RPM1-triggered cell death. Basal and starvation-induced autophagy appeared normal in the nca1 and cat2 mutants. By contrast, autophagic degradation induced by avrRpm1 challenge was compromised, indicating that catalase acted upstream of immunity-triggered autophagy. The direct interaction of catalase with reactive oxygen species could allow catalase to act as a molecular link between reactive oxygen species and the promotion of autophagy-dependent cell death. PMID:24285797
Li, Miao; Qi, Shuo; Jin, Yiguang; Yao, Weishang; Zhang, Sa; Zhao, Jingyu
2014-11-01
Lipid derivatives of nucleoside analogs and their nanoassemblies have become the research hotspot due to their unique function in cancer therapy. Six lipid derivatives of 3'-hydroxyurea-deoxythymidine were prepared with zidovudine as the raw material. The 5'-substituted lipid chains in the derivatives were from the various fatty acids including octanoic acid, decanoic acid, dodecanoic acid, tetradecanoic acid, hexadecanoic acid and octadecanoic acid corresponding to the derivatives OHT, DHT, DDHT, TDHT, HDHT and ODHT. The amphiphilic derivatives formed Langmuir monolayers at the air/water interface with different surface pressure-molecular area isotherms depending on the length of lipid chains. The nanoassemblies of OHT, DHT, DDHT, TDHT and HDHT and the nanoscale precipitates of ODHT were obtained after we injected their tetrahydrofuran solutions doped with hydrophilic long chained polymers into water. Electron microscopy showed that the morphology of nanoassemblies may be vesicles or nanotubes depending on the length of lipid chains. The shorter the lipid chains were, the softer the nanoassemblies. Computer simulation supported the experimental results. The nanoassemblies and the nanoscale precipitates showed much higher anticancer effects on SW620 cells than the parent drug hydroxyurea. The nanostructures of the derivatives are promising anticancer nanomedicines. Copyright © 2014 Elsevier B.V. All rights reserved.
Wang, Shao-Win; Toda, Takashi; MacCallum, Robert; Harris, Adrian L.; Norbury, Chris
2000-01-01
The S-M checkpoint is an intracellular signaling pathway that ensures that mitosis is not initiated in cells undergoing DNA replication. We identified cid1, a novel fission yeast gene, through its ability when overexpressed to confer specific resistance to a combination of hydroxyurea, which inhibits DNA replication, and caffeine, which overrides the S-M checkpoint. Cid1 overexpression also partially suppressed the hydroxyurea sensitivity characteristic of DNA polymerase δ mutants and mutants defective in the “checkpoint Rad” pathway. Cid1 is a member of a family of putative nucleotidyltransferases including budding yeast Trf4 and Trf5, and mutation of amino acid residues predicted to be essential for this activity resulted in loss of Cid1 function in vivo. Two additional Cid1-like proteins play similar but nonredundant checkpoint-signaling roles in fission yeast. Cells lacking Cid1 were found to be viable but specifically sensitive to the combination of hydroxyurea and caffeine and to be S-M checkpoint defective in the absence of Cds1. Genetic data suggest that Cid1 acts in association with Crb2/Rhp9 and through the checkpoint-signaling kinase Chk1 to inhibit unscheduled mitosis specifically when DNA polymerase δ or ɛ is inhibited. PMID:10757807
Italia, Khushnooma; Chandrakala, S; Ghosh, Kanjaksha; Colah, Roshan
2016-09-01
In this study, we hypothesize that hydroxyurea could provide an additional benefit as a free radical scavenger and/or iron chelator in β-thalassemia patients with iron overload. Twenty-one β-thalassemia intermedia patients who presented between 3 and 17 years but later required regular blood transfusions were enrolled for hydroxyurea therapy for a year. Fourteen patients responded to the therapy with hemoglobin levels maintained above 7.5 g/dl without transfusions. Hydroxyurea was discontinued after 6 months in seven patients who did not respond to the therapy and had to be continued on regular blood transfusions. We observed a statistically significant decrease in serum ferritin levels from 4194 ± 4850 ng/ml to 2129 ± 2380 ng/ml among the responders and from 2955 ± 2909 ng/ml to 2040 ± 2432 ng/ml among the non-responders and statistically significant decrease in labile iron pool from 18678.7 ± 10067.4 mean fluorescence intensity (MFI) to 14888.5 ± 5284.0 MFI among responders and from 17986.3 ± 9079.8 MFI to 15634.8 ± 8976.9 MFI among the non-responders after therapy. Phosphatidylserine externalization also showed a statistically significant decrease from 44.2 ± 22.2 MFI to 16.6 ± 6.7 MFI among the responders and from 46.9 ± 33.1 MFI to 39.8 ± 7.4 MFI among the non-responders along with a statistically significant decrease in the levels of reactive oxygen species from 72.8 ± 35.5 MFI to 29.0 ± 8.3 MFI among the responders and from 80.9 ± 41.4 MFI to 40.5 ± 15.8 MFI among the non-responders after therapy. A statistically significant increase in reduced glutathione levels was also observed from 430.8 ± 201.1 MFI to 715.5 ± 292.4 MFI among the responders and from 359.6 ± 165.6 MFI to 450.3 ± 279.5 MFI among the non-responders after therapy. This suggests the possible additional role of hydroxyurea as a free radical scavenger and/or iron chelator but requires a larger study for substantiation.
Aloni, Michel Ntetani; Kadima, Bertin Tshimanga; Ekulu, Pépé Mfutu; Budiongo, Aléine Nzazi; Ngiyulu, René Makuala; Gini-Ehungu, Jean Lambert
2017-06-01
In the Democratic Republic of Congo, the incidence of sickle cell anemia (SCA) is estimated to affect 30,000 to 40,000 neonates per year. However, there is paucity of data on acute clinical manifestations in sickle cell children. In these circumstances, it is difficult to develop a health care policy for an adequate management of sickle cell patients. This was a seven years' retrospective study of children admitted with acute sickle cell crisis in the Department of Pediatrics in University Hospital of Kinshasa, Kinshasa, the Democratic Republic of Congo. A total of 108 patients were identified as having SCA. There were 56 (51%) girls and 52 (49%) boys. Median age was 10.5 years (range 1-24 years). No child was diagnosed by neonatal screening. The median age of diagnosis of sickle cell anemia was 90 months (range: 8-250 months). The median age at the first transfusion was 36 months (range 4-168). In this series, 61 (56.5%) patients were eligible for hydroxyurea. However, this treatment was only performed in 4 (6.6%) of them. Pain episodes, acute anemic crisis and severe infection represent respectively 38.2%, 34.3% and 21.9% of events. Altered sensorium and focal deficit were encountered occasionally and represented 3.4% of acute events. Acute renal manifestations, cholelithiasis and priapism were rarely reported, in this cohort. In Kinshasa, the care of patients suffering from sickle cell anemia is characterized by the delayed diagnosis and low detection of organ complications compared to reports of Western countries. This situation is due to resources deficiencies.
Translating sickle cell guidelines into practice for primary care providers with Project ECHO
Shook, Lisa M.; Farrell, Christina B.; Kalinyak, Karen A.; Nelson, Stephen C.; Hardesty, Brandon M.; Rampersad, Angeli G.; Saving, Kay L.; Whitten-Shurney, Wanda J.; Panepinto, Julie A.; Ware, Russell E.; Crosby, Lori E.
2016-01-01
Background Approximately 100,000 persons with sickle cell disease (SCD) live in the United States, including 15,000 in the Midwest. Unfortunately, many patients experience poor health outcomes due to limited access to primary care providers (PCPs) who are prepared to deliver evidence-based SCD care. Sickle Treatment and Outcomes Research in the Midwest (STORM) is a regional network established to improve care and outcomes for individuals with SCD living in Indiana, Illinois, Michigan, Minnesota, Ohio, and Wisconsin. Methods STORM investigators hypothesized that Project ECHO® methodology could be replicated to create a low-cost, high-impact intervention to train PCPs in evidence-based care for pediatric and young adult patients with SCD in the Midwest, called STORM TeleECHO. This approach utilizes video technology for monthly telementoring clinics consisting of didactic and case-based presentations focused on the National Heart, Lung and Blood Institute (NHLBI) evidence-based guidelines for SCD. Results Network leads in each of the STORM states assisted with developing the curriculum and are recruiting providers for monthly clinics. To assess STORM TeleECHO feasibility and acceptability, monthly attendance and satisfaction data are collected. Changes in self-reported knowledge, comfort, and practice patterns will be compared with pre-participation, and 6 and 12 months after participation. Conclusions STORM TeleECHO has the potential to increase implementation of the NHLBI evidence-based guidelines, especially increased use of hydroxyurea, resulting in improvements in the quality of care and outcomes for children and young adults with SCD. This model could be replicated in other pediatric chronic illness conditions to improve PCP knowledge and confidence in delivering evidence-based care. PMID:27887664
Aloni, Michel Ntetani; Kadima, Bertin Tshimanga; Ekulu, Pépé Mfutu; Budiongo, Aléine Nzazi; Ngiyulu, René Makuala; Gini-Ehungu, Jean Lambert
2017-01-01
In the Democratic Republic of Congo, the incidence of sickle cell anemia (SCA) is estimated to affect 30,000 to 40,000 neonates per year. However, there is paucity of data on acute clinical manifestations in sickle cell children. In these circumstances, it is difficult to develop a health care policy for an adequate management of sickle cell patients. This was a seven years’ retrospective study of children admitted with acute sickle cell crisis in the Department of Pediatrics in University Hospital of Kinshasa, Kinshasa, the Democratic Republic of Congo. A total of 108 patients were identified as having SCA. There were 56 (51%) girls and 52 (49%) boys. Median age was 10.5 years (range 1-24 years). No child was diagnosed by neonatal screening. The median age of diagnosis of sickle cell anemia was 90 months (range: 8-250 months). The median age at the first transfusion was 36 months (range 4-168). In this series, 61 (56.5%) patients were eligible for hydroxyurea. However, this treatment was only performed in 4 (6.6%) of them. Pain episodes, acute anemic crisis and severe infection represent respectively 38.2%, 34.3% and 21.9% of events. Altered sensorium and focal deficit were encountered occasionally and represented 3.4% of acute events. Acute renal manifestations, cholelithiasis and priapism were rarely reported, in this cohort. In Kinshasa, the care of patients suffering from sickle cell anemia is characterized by the delayed diagnosis and low detection of organ complications compared to reports of Western countries. This situation is due to resources deficiencies. PMID:28626540
Testolin, C G; Gore, R; Rivkin, T; Horlick, M; Arbo, J; Wang, Z; Chiumello, G; Heymsfield, S B
2000-12-01
Dual-energy X-ray absorptiometry (DXA) percent (%) fat estimates may be inaccurate in young children, who typically have high tissue hydration levels. This study was designed to provide a comprehensive analysis of pediatric tissue hydration effects on DXA %fat estimates. Phase 1 was experimental and included three in vitro studies to establish the physical basis of DXA %fat-estimation models. Phase 2 extended phase 1 models and consisted of theoretical calculations to estimate the %fat errors emanating from previously reported pediatric hydration effects. Phase 1 experiments supported the two-compartment DXA soft tissue model and established that pixel ratio of low to high energy (R values) are a predictable function of tissue elemental content. In phase 2, modeling of reference body composition values from birth to age 120 mo revealed that %fat errors will arise if a "constant" adult lean soft tissue R value is applied to the pediatric population; the maximum %fat error, approximately 0.8%, would be present at birth. High tissue hydration, as observed in infants and young children, leads to errors in DXA %fat estimates. The magnitude of these errors based on theoretical calculations is small and may not be of clinical or research significance.
Proteomic analysis of the response to cell cycle arrests in human myeloid leukemia cells
Ly, Tony; Endo, Aki; Lamond, Angus I
2015-01-01
Abstract Previously, we analyzed protein abundance changes across a ‘minimally perturbed’ cell cycle by using centrifugal elutriation to differentially enrich distinct cell cycle phases in human NB4 cells (Ly et al., 2014). In this study, we compare data from elutriated cells with NB4 cells arrested at comparable phases using serum starvation, hydroxyurea, or RO-3306. While elutriated and arrested cells have similar patterns of DNA content and cyclin expression, a large fraction of the proteome changes detected in arrested cells are found to reflect arrest-specific responses (i.e., starvation, DNA damage, CDK1 inhibition), rather than physiological cell cycle regulation. For example, we show most cells arrested in G2 by CDK1 inhibition express abnormally high levels of replication and origin licensing factors and are likely poised for genome re-replication. The protein data are available in the Encyclopedia of Proteome Dynamics (http://www.peptracker.com/epd/), an online, searchable resource. DOI: http://dx.doi.org/10.7554/eLife.04534.001 PMID:25555159
L-glutamine for sickle cell anemia: more questions than answers.
Quinn, Charles T
2018-06-12
In 2017, the Food and Drug Administration (FDA) approved two medications for sickle cell anemia (SCA): hydroxyurea for children (≥2 years of age) and L-glutamine for children and adults (≥5 years). The approval of hydroxyurea for children was long overdue, having been authorized by the FDA for adults in 1998 and by the European Medicines Agency for adults and children in 2007, but the approval of L-glutamine was a surprise to many in the field. There are few published studies of L-glutamine as a treatment for SCA, so all can be reviewed in this brief manuscript. Accordingly, there are many unanswered questions about L-glutamine and its role in current therapy for SCA. Copyright © 2018 American Society of Hematology.
Ghafuri, Djamila Labib; Chaturvedi, Shruti; Rodeghier, Mark; Stimpson, Sarah-Jo; McClain, Brandi; Byrd, Jeannie; DeBaun, Michael R
2017-07-01
In a retrospective cohort study, we tested the hypothesis that when prescribing hydroxyurea (HU) to children with sickle cell anemia (SCA) to prevent vaso-occlusive events, there will be a secondary benefit of maintaining low transcranial Doppler (TCD) velocity, measured by imaging technique (TCDi). HU was prescribed for 90.9% (110 of 120) of children with SCA ≥5 years of age and followed for a median of 4.4 years, with 70% (n = 77) receiving at least one TCDi evaluation after starting HU. No child prescribed HU had a conditional or abnormal TCDi measurement. HU initiation for disease severity prevention decreases the prevalence of abnormal TCDi velocities. © 2016 Wiley Periodicals, Inc.
Efficacy and Safety of Ruxolitinib in the Treatment of Patients with Myelofibrosis
Yi, Cecilia Arana; Tam, Constantine S.; Verstovsek, Srdan
2016-01-01
The JAK 1 and JAK2 inhibitor ruxolitinib has approved indications in myelofibrosis, a BCR-ABL1-negative myeloproliferative neoplasm associated with progressive bone marrow fibrosis and shortened survival. In Phase III clinical studies, ruxolitinib provided rapid and durable improvement of myelofibrosis-related splenomegaly and symptoms irrespective of mutation status, and was associated with a survival advantage compared with placebo or best available therapy. Because of dose-dependent cytopenias, blood count monitoring and dose titration are important to optimize therapy. Specific precautions apply to the treatment of patients with or at risk of serious infections. Discontinuation of ruxolitinib generally leads to symptom return within 1 week. Ruxolitinib also is approved for treatment of patients with polycythemia vera who have had an inadequate response to or are intolerant of hydroxyurea. PMID:25757677
Patterson, Chavis A; Barakat, Lamia P; Henderson, Phyllis K; Nall, Faith; Westin, Anna; Dampier, Carlton D; Hsu, Lewis L
2011-01-01
Communicating risk is an important activity in medical decision-making; yet, numeracy is not a universal skill among the American public. We examined the hypothesis that numerical risk information about the use of hydroxyurea for children with sickle cell disease would elicit different risk assessment responses when visual depictions were used instead of abstract numbers and depending on the disease severity. Parents of 81 children with sickle cell disease participated in a survey in which hydroxyurea was first described as carrying a certain chance of risk for both birth defects and cancer. Then, the parents indicated the highest risk at which they would hypothetically consent to the treatment to help their child. Risk presentations were repeated with abstract numerical, pie graph, and 1000 people histogram formats. The χ analyses comparing high-risk to low-risk assessment across presentation formats showed high consistency between visual depictions but low consistency of abstract numerical with visual depictions. The parents of children with SC and other less severe types of SCD were less willing to accept higher risk than those with SS when the data were presented numerically. Given earlier concerns about poor "numeracy" in the US population, visual depictions of risk could be an effective tool for routine communication in health education and medical decision-making.
De Montalembert, M; Tshilolo, L
2007-12-01
The life expectancy of patients with sickle cell disease has improved in the United States and Europe thanks to the use of penicillin prophylaxis, appropriate immunizations, neonatal screening, implementation of a quality transfusional policy, hydroxyurea therapy, detection and treatment of cerebral vasculopathy, recognition of situations that can benefit from allogenic marrow transplantation, and improvements in bone marrow transplantation techniques. The cost of almost all these techniques is far beyond the means of health care systems in Africa where they cannot be used. However at least three, i.e., penicillin, vaccines, and hydroxyurea, could be easily accessible in the framework of defined therapeutic strategies. If daily penicillin and pneumococcal vaccine Pneumo 23 are required, it would likely be necessary to select a conjugated vaccine other than Prevenar that does not provide protection against all strains present in Africa. Neonatal screening is still a rare procedure in sub-Saharan countries. Periodic transfusion is steadily improving but exchange transfusion programs aimed in particular at preventing neurological complications are still unfeasible. Indications for hydroxyurea therapy in Africa are more common due to the lack of access to chronic transfusion and must be based on consensus decision. Use of bone marrow transplantation, i.e., the only currently available curative treatment, is still possible only in northern hemisphere countries where it is still restricted to children with severe forms and an HLA-compatible family donor.
Toxicity of hydroxyurea in rats and dogs.
Morton, Daniel; Reed, Lori; Huang, Wenhu; Marcek, John M; Austin-LaFrance, Robert; Northcott, Carrie A; Schelling, Scott H; Enerson, Bradley E; Tomlinson, Lindsay
2015-06-01
The toxicity of hydroxyurea, a treatment for specific neoplasms, sickle-cell disease, polycythemia, and thrombocytosis that kills cells in mitosis, was assessed in repeat-dose, oral gavage studies in rats and dogs and a cardiovascular study in telemetered dogs. Hydroxyurea produced hematopoietic, lymphoid, cardiovascular, and gastrointestinal toxicity with steep dose response curves. In rats dosed for 10 days, 50 mg/kg/day was tolerated; 500 mg/kg/day produced decreased body weight gain; decreased circulating leukocytes, erythrocytes, and platelets; decreased cellularity of thymus, lymph nodes, and bone marrow; and epithelial degeneration and/or dysplasia of the stomach and small intestine; 1,500 mg/kg/day resulted in deaths on day 5. In dogs, a single dose at ≥ 250 mg/kg caused prostration leading to unscheduled euthanasia. Dogs administered 50 mg/kg/day for 1 month had decreased circulating leukocytes, erythrocytes, and platelets; increased bone marrow cellularity with decreased maturing granulocytes; increased creatinine kinase activity; and increased iron pigment in bone marrow and hepatic sinusoidal cells. In telemetered dogs, doses ≥ 15 mg/kg decreased systolic blood pressure (BP); 50 mg/kg increased diastolic BP, heart rate, and change in blood pressure over time (+dP/dt), and decreased QT and PR intervals and maximum left ventricular systolic and end diastolic pressures with measures returning to control levels within 24 hr. © 2014 by The Author(s).
NASA Astrophysics Data System (ADS)
DePrince, A. Eugene; Mazziotti, David A.
2010-01-01
The parametric variational two-electron reduced-density-matrix (2-RDM) method is applied to computing electronic correlation energies of medium-to-large molecular systems by exploiting the spatial locality of electron correlation within the framework of the cluster-in-molecule (CIM) approximation [S. Li et al., J. Comput. Chem. 23, 238 (2002); J. Chem. Phys. 125, 074109 (2006)]. The 2-RDMs of individual molecular fragments within a molecule are determined, and selected portions of these 2-RDMs are recombined to yield an accurate approximation to the correlation energy of the entire molecule. In addition to extending CIM to the parametric 2-RDM method, we (i) suggest a more systematic selection of atomic-orbital domains than that presented in previous CIM studies and (ii) generalize the CIM method for open-shell quantum systems. The resulting method is tested with a series of polyacetylene molecules, water clusters, and diazobenzene derivatives in minimal and nonminimal basis sets. Calculations show that the computational cost of the method scales linearly with system size. We also compute hydrogen-abstraction energies for a series of hydroxyurea derivatives. Abstraction of hydrogen from hydroxyurea is thought to be a key step in its treatment of sickle cell anemia; the design of hydroxyurea derivatives that oxidize more rapidly is one approach to devising more effective treatments.
Diagnosis and Management of Polycythemia Vera in a Ferret (Mustela putorius furo).
Le, Kim; Beaufrère, Hugues; Bassel, Laura L; Wills, Sarah; Laniesse, Delphine; Blois, Shauna L; Smith, Dale A
2016-12-01
A 5-y-old female ferret (Mustela putorius furo) was evaluated for diarrhea, anorexia, and lethargy for 1 wk. Only mild dehydration was detected on physical examination. CBC analysis revealed marked erythrocytosis with an unremarkable plasma biochemistry panel; follow-up CBC analyses revealed a consistent primary erythrocytosis. Whole-body radiographs and abdominal ultrasonography were unremarkable except for a small nephrolith in the right kidney and a small cyst in the left kidney. The plasma erythropoietin level was 17.0 mIU/mL and considered normal. In light of the diagnostic work-up and consistent erythrocytosis, a diagnosis of polycythemia vera (primary erythrocytosis) was made. The initial presentation of diarrhea resolved after treatment with oral metronidazole (20 mg/kg PO BID for 7 d). Treatment for the polycythemia consisted of a phlebotomy initially followed by chemotherapy with hydroxyurea (10 mg/kg PO BID). During the subsequent 12 mo, the hydroxyurea dose adjusted according to follow-up CBC results, and finding an optimal dosage regimen proved to be challenging. One year after the initial diagnosis, the ferret presented to an emergency clinic for acute and severe hemorrhagic diarrhea and died shortly thereafter. The postmortem diagnosis was acute venous infarction of the small and large intestine. To our knowledge, this report is the first to describe the diagnosis and long-term management of polycythemia vera in a ferret and the use of hydroxyurea for this purpose.
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Hydroxycarbamide-Induced Changes in E/beta Thalassemia Red Blood Cells
Sylvia, Singer T.; Elliott, Vichinsky; Sandra, Larkin; Nancy, Olivieri; Nancy, Sweeters; Frans, Kuypers A.
2010-01-01
In thalassemia, fetal hemoglobin (HbF) augmentation with hydroxycarbamide (also known as hydroxyurea) is not always successful. The expected parallel effects on RBC membrane deformability, cell hydration and membrane phospholipid organization, all important for extending RBC life span and increasing Hb, have been infrequently examined. We analyzed these characteristics in 15 non-transfused E/β 0 thalassemia patients treated with HU (mean 10.2 months). Membrane deformability and cell hydration mildly improved in association with increased HbF levels approaching statistical significance (r = 0.51, p=0.06). All measures improved considerably splenectomized patients. These findings underscore the disappointing results of hydroxyurea treatment in clinical trials; and the importance of examining the effect on red cell characteristics for the development and understanding of HbF-enhancing agents. PMID:18821710
Verzì, Anna Elisa; Bubley, Jeffrey A; Haugh, Alexandra M; Zhang, Bin; Wagner, Annette; Kruse, Lacey; West, Dennis P; Wayne, Jeffrey; Guitart, Joan; Gerami, Pedram
2017-11-01
The epidemiology of pediatric melanoma is distinct from that seen in adults. This is more distinguishable when pediatric patients are separated into prepubertal and adolescent groups. In this study, we compared epidemiologic, clinical, histologic, and molecular characteristics of pediatric superficial spreading melanoma (SSM) in prepubertal and adolescent patients to that in adults. We reviewed our database for pediatric melanomas, comparing SSM data between pediatric and adult cases for pathologic stage at presentation, ratio of radial to vertical growth phase, average Breslow depth and mitotic index, and frequency of fluorescence in situ hybridization (FISH) positivity. Of 84 pediatric melanomas, 38 were SSM, and 5 of the latter (6%) were prepubertal. There were no significant differences when pediatric and adult SSM were compared for stage at presentation, ratio of radial to vertical growth phase, average Breslow depth and mitotic count, or frequency of FISH positivity. A significant difference was detected for SSM arising from a precursor nevus (80% of pediatric cases versus 30% of adult cases). Follow-up time was limited for both cohorts. SSM melanoma is infrequent in childhood, particularly in the prepubertal years. Features such as tumor stage, Breslow depth, mitotic activity, and FISH positivity suggest morphologic and molecular characteristics similar to those of adult SSM. Copyright © 2017 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.
From leeches to personalized medicine: evolving concepts in the management of polycythemia vera.
Vannucchi, Alessandro M
2017-01-01
Polycythemia vera is a clonal disorder of hematopoietic stem/progenitor cells. It manifests as an expansion of red cell mass. It is the most common chronic myeloproliferative neoplasm. In virtually all cases, it is characterized by a V617F point mutation in JAK2 exon 14 or less common mutations in exon 12. The landmark discovery of the autonomously activated JAK/STAT signaling pathway paved the way for the clinical development of the first target drug, the JAK1 and JAK2 inhibitor ruxolitinib. This is now approved for patients with resistance or intolerance to hydroxyurea. Phlebotomies and hydroxyurea are still the cornerstone of treatment, and aim to prevent the first appearance or recurrence of cardiovascular events that, together with progression to post-polycythemia vera myelofibrosis and leukemia, represent the main causes of death. Interferon-α is an alternative drug and has been shown to induce molecular remissions. It is currently undergoing phase III trials that might eventually lead to its approval for clinical use. The last few years have witnessed important advances towards an accurate early diagnosis of polycythemia vera, greater understanding of its pathogenesis, and improved patient management. This review will focus on the most recent achievements and will aim to unify the different concepts involved in a personalized approach to the patient with polycythemia vera. In spite of many recent advances in the understanding of its pathogenesis and improved disease management, polycythemia vera remains a life-threatening myeloproliferative neoplasm for which there is no cure. This review will present a critical overview of evolving concepts in diagnosis and treatment of this disease. Copyright© Ferrata Storti Foundation.
Mazza, Elena; Brandes, Alba; Zanon, Silvia; Eoli, Marika; Lombardi, Giuseppe; Faedi, Marina; Franceschi, Enrico; Reni, Michele
2016-01-01
Hydroxyurea (HU) is among the most widely used salvage therapies in progressive meningiomas. Platelet-derived growth factor receptors are expressed in virtually all meningiomas. Imatinib sensitizes transformed cells to the cytotoxic effects of chemotherapeutic agents that interfere with DNA metabolism. The combination of HU with imatinib yielded intriguing results in recurrent malignant glioma. The current trial addressed the activity of this association against meningioma. Patients with recurrent or progressive WHO grade I-III meningioma, without therapeutic indication for surgery, radiotherapy, or stereotactic radiosurgery, aged 18-75 years, ECOG performance status 0-2, and not on enzyme-inducing anti-epileptic drugs were randomized to receive HU 500 mg BID ± imatinib 400 mg QD until progression, unacceptable toxicity, or patient's refusal. The primary endpoint was progression-free survival rate at 9 months (PFS-9). Between September 2009 and February 2012, 15 patients were randomized to receive HU + imatinib (N = 7; Arm A) or HU alone (N = 8; Arm B). Afterward the trial was prematurely closed due to slow enrollment rate. PFS-9 (A/B) was 0/75%, and median PFS was 4/19.5 months. Median and 2-year overall survival (A/B) rates were: 6/27.5 months; 28.5/75%, respectively. Main G3-4 toxicities were: G3 neutropenia in 1/0, G4 headache in 1/1, and G3 vomiting in 1/0. The conduction of a study in recurrent or progressive meningioma remains a challenge. Given the limited number of patients enrolled, no firm conclusions can be drawn about the combination of imatinib and HU. The optimal systemic therapy for meningioma failing surgery and radiation has yet to be identified.
From leeches to personalized medicine: evolving concepts in the management of polycythemia vera
Vannucchi, Alessandro M.
2017-01-01
Polycythemia vera is a clonal disorder of hematopoietic stem/progenitor cells. It manifests as an expansion of red cell mass. It is the most common chronic myeloproliferative neoplasm. In virtually all cases, it is characterized by a V617F point mutation in JAK2 exon 14 or less common mutations in exon 12. The landmark discovery of the autonomously activated JAK/STAT signaling pathway paved the way for the clinical development of the first target drug, the JAK1 and JAK2 inhibitor ruxolitinib. This is now approved for patients with resistance or intolerance to hydroxyurea. Phlebotomies and hydroxyurea are still the cornerstone of treatment, and aim to prevent the first appearance or recurrence of cardiovascular events that, together with progression to post-polycythemia vera myelofibrosis and leukemia, represent the main causes of death. Interferon-α is an alternative drug and has been shown to induce molecular remissions. It is currently undergoing phase III trials that might eventually lead to its approval for clinical use. The last few years have witnessed important advances towards an accurate early diagnosis of polycythemia vera, greater understanding of its pathogenesis, and improved patient management. This review will focus on the most recent achievements and will aim to unify the different concepts involved in a personalized approach to the patient with polycythemia vera. In spite of many recent advances in the understanding of its pathogenesis and improved disease management, polycythemia vera remains a life-threatening myeloproliferative neoplasm for which there is no cure. This review will present a critical overview of evolving concepts in diagnosis and treatment of this disease. PMID:27884974
Ruxolitinib versus standard therapy for the treatment of polycythemia vera.
Vannucchi, Alessandro M; Kiladjian, Jean Jacques; Griesshammer, Martin; Masszi, Tamas; Durrant, Simon; Passamonti, Francesco; Harrison, Claire N; Pane, Fabrizio; Zachee, Pierre; Mesa, Ruben; He, Shui; Jones, Mark M; Garrett, William; Li, Jingjin; Pirron, Ulrich; Habr, Dany; Verstovsek, Srdan
2015-01-29
Ruxolitinib, a Janus kinase (JAK) 1 and 2 inhibitor, was shown to have a clinical benefit in patients with polycythemia vera in a phase 2 study. We conducted a phase 3 open-label study to evaluate the efficacy and safety of ruxolitinib versus standard therapy in patients with polycythemia vera who had an inadequate response to or had unacceptable side effects from hydroxyurea. We randomly assigned phlebotomy-dependent patients with splenomegaly, in a 1:1 ratio, to receive ruxolitinib (110 patients) or standard therapy (112 patients). The primary end point was both hematocrit control through week 32 and at least a 35% reduction in spleen volume at week 32, as assessed by means of imaging. The primary end point was achieved in 21% of the patients in the ruxolitinib group versus 1% of those in the standard-therapy group (P<0.001). Hematocrit control was achieved in 60% of patients receiving ruxolitinib and 20% of those receiving standard therapy; 38% and 1% of patients in the two groups, respectively, had at least a 35% reduction in spleen volume. A complete hematologic remission was achieved in 24% of patients in the ruxolitinib group and 9% of those in the standard-therapy group (P=0.003); 49% versus 5% had at least a 50% reduction in the total symptom score at week 32. In the ruxolitinib group, grade 3 or 4 anemia occurred in 2% of patients, and grade 3 or 4 thrombocytopenia occurred in 5%; the corresponding percentages in the standard-therapy group were 0% and 4%. Herpes zoster infection was reported in 6% of patients in the ruxolitinib group and 0% of those in the standard-therapy group (grade 1 or 2 in all cases). Thromboembolic events occurred in one patient receiving ruxolitinib and in six patients receiving standard therapy. In patients who had an inadequate response to or had unacceptable side effects from hydroxyurea, ruxolitinib was superior to standard therapy in controlling the hematocrit, reducing the spleen volume, and improving symptoms associated with polycythemia vera. (Funded by Incyte and others; RESPONSE ClinicalTrials.gov number, NCT01243944.).
Onishi, Taku; Tsukamoto, Katsura; Matsumaru, Naoki; Waki, Takashi
2018-01-01
Efforts to promote the development of pediatric pharmacotherapy include regulatory frameworks and close collaboration between the US Food and Drug Administration and the European Medicines Agency. We characterized the current status of pediatric clinical trials conducted in the United States by the pharmaceutical industry, focusing on the involvement of the European Union member countries, to clarify the industry perspective. Data on US pediatric clinical trials were obtained from ClinicalTrials.gov . Binary regression analysis was performed to identify what factors influence the likelihood of involvement of European Union countries. A total of 633 US pediatric clinical trials that met inclusion criteria were extracted and surveyed. Of these, 206 (32.5%) involved a European Union country site(s). The results of binary regression analysis indicated that attribution of industry, phase, disease area, and age of pediatric participants influenced the likelihood of the involvement of European Union countries in US pediatric clinical trials. Relatively complicated or large pediatric clinical trials, such as phase II and III trials and those that included a broad age range of participants, had a significantly greater likelihood of the involvement of European Union countries ( P < .05). Our results suggest that (1) the pharmaceutical industry utilizes regulatory frameworks in making business decisions regarding pediatric clinical trials, (2) disease area affects the involvement of European Union countries, and (3) feasibility of clinical trials is mainly concerned by pharmaceutical industry for pediatric drug development. Additional incentives for high marketability may further motivate pharmaceutical industry to develop pediatric drugs.
Han, Jin; Bhat, Shubha; Gowhari, Michel; Gordeuk, Victor R; Saraf, Santosh L
2016-11-01
Ambulatory care clinical pharmacy services have expanded beyond primary care settings, but literature supporting the benefits of clinical pharmacy involvement with patients who have rare diseases such as sickle cell disease (SCD) is lacking. Hydroxyurea is the only agent approved by the U.S. Food and Drug Administration for the treatment of SCD; full benefit in controlling pain episodes and other complications is achieved through monitored escalation to a maximum tolerated dose. The primary objective of this analysis was to evaluate the impact of a newly implemented clinical pharmacy service on the management of patients with SCD. We performed a retrospective cross-sectional analysis of 385 adults with SCD who received care between January 1, 2014, and December 31, 2014, at a single Sickle Cell Outpatient Center that implemented a clinical pharmacy service in August 2013. Data were collected on hydroxyurea dose escalation, immunization completion rates, and health maintenance metrics (screening for nephropathy with microalbuminuria testing, retinopathy with annual retinal examinations, and pulmonary hypertension with echocardiography). The impact of the clinical pharmacy service on quality measurements was evaluated by using univariate and multivariate analyses. The number of pharmacist encounters, defined as a clinic visit when a clinical pharmacist interacted with a patient as documented in the medical records, was associated with an improved hydroxyurea dose escalation rate (odds ratio [OR] 1.48, 95% confidence interval [CI] 1.07-2.05, p=0.02). Immunization rates for the 23-valent pneumococcal polysaccharide vaccine, the 13-valent pneumococcal conjugate vaccine, and influenza vaccine were 66%, 47%, and 62%, respectively. The number of pharmacist encounters was associated with improved immunization completion rates (OR 1.38, 95% CI 1.17-1.62, p<0.001). Improved screening for microalbuminuria (OR 2.14, 95% CI 1.60-2.86, p<0.001) and sickle cell retinopathy (OR 1.16, 95% CI 1.00-1.35, p=0.05) were also associated with the number of pharmacist encounters. A new clinical pharmacy service implemented in managing a rare disease, SCD, was associated with an improved hydroxyurea dose escalation rate, immunization completion rates, and health maintenance metrics. © 2016 Pharmacotherapy Publications, Inc.
Lee, Laura; Rodriguez, Jairo; Tsukiyama, Toshio
2015-01-01
When cells undergo replication stress, proper checkpoint activation and deactivation are critical for genomic stability and cell survival and therefore must be highly regulated. Although mechanisms of checkpoint activation are well studied, mechanisms of checkpoint deactivation are far less understood. Previously, we reported that chromatin remodeling factors Isw2 and Ino80 attenuate the S-phase checkpoint activity in Saccharomyces cerevisiae, especially during recovery from hydroxyurea. In this study, we found that Isw2 and Ino80 have a more pronounced role in attenuating checkpoint activity during late S phase in the presence of methyl methanesulfonate (MMS). We therefore screened for checkpoint factors required for Isw2 and Ino80 checkpoint attenuation in the presence of MMS. Here we demonstrate that Isw2 and Ino80 antagonize checkpoint activators and attenuate checkpoint activity in S phase in MMS either through a currently unknown pathway or through RPA. Unexpectedly, we found that Isw2 and Ino80 increase chromatin accessibility around replicating regions in the presence of MMS through a novel mechanism. Furthermore, through growth assays, we provide additional evidence that Isw2 and Ino80 partially counteract checkpoint activators specifically in the presence of MMS. Based on these results, we propose that Isw2 and Ino80 attenuate S-phase checkpoint activity through a novel mechanism. PMID:25701287
Phosphatidylcholine catabolism in the MCF-7 cell cycle.
Lin, Weiyang; Arthur, Gilbert
2006-10-01
The catabolism of phosphatidylcholine (PtdCho) appears to play a key role in regulating the net accumulation of the lipid in the cell cycle. Current protocols for measuring the degradation of PtdCho at specific cell-cycle phases require prolonged periods of incubation with radiolabelled choline. To measure the degradation of PtdCho at the S and G2 phases in the MCF-7 cell cycle, protocols were developed with radiolabelled lysophosphatidylcholine (lysoPtdCho), which reduces the labelling period and minimizes the recycling of labelled components. Although most of the incubated lysoPtdCho was hydrolyzed to glycerophosphocholine (GroPCho) in the medium, the kinetics of the incorporation of label into PtdCho suggests that the labelled GroPCho did not contribute significantly to cellular PtdCho formation. A protocol which involved exposing the cells twice to hydroxyurea, was also developed to produce highly synchronized MCF-7 cells with a profile of G1:S:G2/M of 90:5:5. An analysis of PtdCho catabolism in the synchronized cells following labelling with lysoPtdCho revealed that there was increased degradation of PtdCho in early to mid-S phase, which was attenuated in the G2/M phase. The results suggest that the net accumulation of PtdCho in MCF-7 cells may occur in the G2 phase of the cell cycle.
Afifi, Rasha Abdel-Raouf; Kamal, Dina; Sayed, Riham El; Ekladious, Sherif M M; Shaheen, Gehan H; Yousry, Sherif M; Hussein, Rania Elsayed
2018-06-01
To detect the frequency of CD209 A>G polymorphism in sickle cell disease (SCD) Egyptian patients and to evaluate the use of CD209 A>G polymorphism as a genetic predictor of SCD clinical heterogeneity. A total of 100 Egyptian children with SCD and 100 Egyptian controls were tested for CD209 A>G polymorphism and were followed up prospectively between June 2012 and December 2014. Comparison of CD209 A>G polymorphism among cases and controls did not show statistically significant difference (p = .742). In addition, comparison of the allelic frequency did not show statistically significant difference (p = .738). Infections occurred more frequently among the heterozygous genotype (AG; 60.5%) and homozygous genotype (GG; 75%) patients than among the wild (AA) genotype (24.1%; p < .001). The use of hydroxyurea treatment was significantly higher among the wild (AA) genotype (47%) than the heterozygous (AG; 21%) and homozygous (GG; 5%) genotypes (p = .003). We found no significant difference between our population of Egyptian SCD cases and controls regarding CD209 A>G polymorphism. Infections occurred more frequently among the heterozygous genotype (AG) and homozygous genotype (GG) patients. Copyright © 2017. Published by Elsevier Ltd.
Mahmoud, Hanan Mohamed; Shoeib, Ahmed Al-Saiid Hamed; Abd El Ghany, Shereen Mohamed; Reda, Marwa Mohamed; Ragab, Iman Ahmed
2015-12-01
The α hemoglobin stabilizing protein (AHSP) binds α-Hb and prevents its precipitation limiting free α-Hb toxicities. Our aim was to study AHSP expression in β thalassemia syndromes in relation to their clinical severity and to compare it with its level in sickle cell anemia. We compared patients with β-thalassemia (n=37) (β-thalassemia major (BTM) (n=19) and β-thalassemia intermedia (BTI) (n=18)) with 12 patients with sickle cell anemia as regards clinical severity, age at presentation, transfusion dependency, mean pre-transfusion hemoglobin level, use of hydroxyurea and AHSP expression by real time quantitative PCR. Median (and IQR) AHSP expression was significantly higher in patients with sickle cell anemia 2275 (3898) compared to thalassemia 283 (718), P=0.001, with no significant difference between BTM and BTI (P=0.346). It was also significantly higher in non-transfusion dependent patients with β thalassemia (NTDT) compared to transfusion dependent ones (P=0.019), and in patients on hydroxyurea therapy (P<0.001). However, there was no significant difference in its level according to clinical severity score (P=0.946) or splenectomy status (P=0.145). AHSP expression was higher in patients with sickle cell anemia versus thalassemia, with no significant difference between BTM and BTI. Expression was higher in patients with NTDT and on hydroxyurea therapy. Copyright © 2015 Elsevier Inc. All rights reserved.
Place, Andrew E; Goldsmith, Kelly; Bourquin, Jean-Pierre; Loh, Mignon L; Gore, Lia; Morgenstern, Daniel A; Sanzgiri, Yeshwant; Hoffman, David; Zhou, Ying; Ross, Jeremy A; Prine, Betty; Shebley, Mohamad; McNamee, Megan; Farazi, Thalia; Kim, Su Young; Verdugo, Maria; Lash-Fleming, Leanne; Zwaan, C Michel; Vormoor, Josef
2018-03-29
Venetoclax is a highly selective, potent BCL-2 inhibitor that is approved for some patients previously treated for chronic lymphocytic leukemia, and has shown promising activity in adult studies across several hematologic malignancies. Preclinical studies have demonstrated venetoclax activity in pediatric patient-derived xenograft models and cell lines; however, clinical studies in pediatric patients have yet to be conducted. The prognosis is poor for children with most relapsed/refractory malignancies, and limited treatment options result in unmet clinical need. Herein, we describe the rationale and design of the first study of venetoclax in pediatric patients with relapsed/refractory malignancies: a Phase I trial investigating the safety and pharmacokinetics of venetoclax monotherapy followed by the addition of chemotherapy (Trial registration: EudraCT 2017-000439-14; NCT03236857).
Negotiating Decisions during Informed Consent for Pediatric Phase I Oncology Trials
Marshall, Patricia A.; Magtanong, Ruth V.; Leek, Angela C.; Hizlan, Sabahat; Yamokoski, Amy D.; Kodish, Eric D.
2012-01-01
During informed consent conferences (ICCs) for Phase I trials, oncologists must present complex information while addressing concerns. Research on communication that evolves during ICCs remains largely unexplored. We examined communication during ICCs for pediatric Phase I cancer trials using a stratified random sample from six pediatric cancer centers. A grounded theory approach identified key communication steps and factors influencing the negotiation of decisions for trial participation. Analysis suggests that during ICCs, families, patients, and clinicians exercise choice and control by negotiating micro-decisions in two broad domains: drug logic and logistics, and administration/scheduling. Micro-decisions unfold in a four-step communication process: (1) introduction of an issue; (2) response; (3) negotiation of the issue; and (4) resolution and decision. Negotiation over smaller micro-decisions is prominent in ICCs and merits further study. PMID:22565583
Negotiating decisions during informed consent for pediatric Phase I oncology trials.
Marshall, Patricia A; Magtanong, Ruth V; Leek, Angela C; Hizlan, Sabahat; Yamokoski, Amy D; Kodish, Eric D
2012-04-01
During informed consent conferences (ICCs) for Phase I trials, oncologists must present complex information while addressing concerns. Research on communication that evolves during ICCs remains largely unexplored. We examined communication during ICCs for pediatric Phase I cancer trials using a stratified random sample from six pediatric cancer centers. A grounded theory approach identified key communication steps and factors influencing the negotiation of decisions for trial participation. Analysis suggests that during ICCs, families, patients, and clinicians exercise choice and control by negotiating micro-decisions in two broad domains: drug logic and logistics, and administration/scheduling. Micro-decisions unfold in a four-step communication process: (1) introduction of an issue; (2) response; (3) negotiation of the issue; and (4) resolution and decision. Negotiation over smaller micro-decisions is prominent in ICCs and merits further study.
Kakodkar, Kedar; Schroeder, James W
2013-08-01
Feeding and swallowing disorders in the pediatric population are becoming more common, particularly in infants born prematurely and in children with chronic medical conditions. The normal swallowing mechanism is divided into 4 stages: the preparatory, the oral, the pharyngeal, and the esophageal phases. Feeding disorders have multiple causes: medical, nutritional, behavioral, psychological, and environmental factors can all contribute. Pathologic conditions involving any of the anatomic sites associated with the phases of swallowing can negatively impact the coordination of these phases and lead to symptoms of dysphagia and feeding intolerance. Copyright © 2013 Elsevier Inc. All rights reserved.
Hardin, Amy Peykoff; Hackell, Jesse M
2017-09-01
Pediatrics is a multifaceted specialty that encompasses children's physical, psychosocial, developmental, and mental health. Pediatric care may begin periconceptionally and continues through gestation, infancy, childhood, adolescence, and young adulthood. Although adolescence and young adulthood are recognizable phases of life, an upper age limit is not easily demarcated and varies depending on the individual patient. The establishment of arbitrary age limits on pediatric care by health care providers should be discouraged. The decision to continue care with a pediatrician or pediatric medical or surgical subspecialist should be made solely by the patient (and family, when appropriate) and the physician and must take into account the physical and psychosocial needs of the patient and the abilities of the pediatric provider to meet these needs. Copyright © 2017 by the American Academy of Pediatrics.
NASA Astrophysics Data System (ADS)
Hesabi, Maryam; Behjatmanesh-Ardakani, Reza
2018-01-01
Nowadays, an important process applied in the design of novel composite materials and drug delivery fields is the carboxylation of carbon nanotubes. In this work, we study the interaction of the anti-cancer drug hydroxyurea with carboxyl-functionalized zigzag carbon nanotubes (CNTs) by employing the method of the density functional theory (DFT) at B3LYP and CAM-B3LYP levels in gas and solvent phases. The results show that all complexes are energetically favorable, especially in the aqueous phase. The enthalpy energy values are negative in all cases, which indicate their exothermic adsorption nature. The presence of sbnd COOH groups would create enough free space on the nanotube surface for the adsorption between interacting atoms. Thus, these can increase the activity of CNTs. Data indicates that adsorption is dependent on the carboxyl sites of the nanotube as well as on the sites of the drug. Furthermore, the hydrogen-bonding interactions between drug and sbnd COOH-CNTs play an important role for the different kinds of adsorption observed.
NCI, FNLCR Help Launch Pediatric MATCH Precision Medicine Trial | Poster
The National Cancer Institute and Children’s Oncology Group recently opened enrollment for a new Phase II trial of personalized precision cancer therapies. Called the Pediatric Molecular Analysis for Therapy Choice (Pediatric MATCH), the trial seeks to treat children and adolescents aged 1–21 whose solid tumors have failed to respond to or re-emerged after traditional cancer
NCI, FNLCR Help Launch Pediatric MATCH Precision Medicine Trial | Poster
The National Cancer Institute and Children’s Oncology Group recently opened enrollment for a new Phase II trial of personalized precision cancer therapies. Called the Pediatric Molecular Analysis for Therapy Choice (Pediatric MATCH), the trial seeks to treat children and adolescents aged 1–21 whose solid tumors have failed to respond to or re-emerged after traditional cancer treatments.
Takazawa, Shinya; Ishimaru, Tetsuya; Harada, Kanako; Deie, Kyoichi; Hinoki, Akinari; Uchida, Hiroo; Sugita, Naohiko; Mitsuishi, Mamoru; Iwanaka, Tadashi; Fujishiro, Jun
2018-05-01
Pediatric robot-assisted surgery is increasingly being performed, but it is difficult to perform this procedure in infants. A pediatric thoracoscopic model of a 1-year-old patient was developed in our previous study, and this model was used to evaluate the use of a surgical robot for infant surgery. Eight pediatric surgeons performed an intracorporeal suturing and knot-tying task using the da Vinci Xi Robotic Surgical System. The task completion time, number of needle manipulations, and force applied during suturing of the robot-assisted thoracoscopic surgery (RATS) group were compared with those of the video-assisted thoracoscopic surgery (VATS) group whose data had been collected from the same 8 surgeons in our previous study. The RATS group showed a significantly shorter completion time than the VATS group in the knot-tying phase (P = .016) and in the total phase (P = .0078). The RATS group showed a significantly smaller number of manipulations than the VATS group in the total phase (P = .039). The RATS group showed a significantly smaller pushing force index than the VATS group in the suturing phase (P = .031), knot-tying phase (P = .031), and in the total phase (P = .031). A seventh rib in the model was dislocated in all RATS group cases. The da Vinci Surgical System might be useful in infants because of fast movement and small pushing force. However, the robotic 8 mm instruments were too large for use in the thoracic cavity of the 1-year-old infant.
Pflieger, M; Bertram, D
2014-10-01
To address the lack of appropriate pediatric drugs available on the global market, in 2000 the International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) issued the ICH E11 guideline regarding the Clinical Investigation of Medicinal Products in the Pediatric Population. This guideline considerably changes the environment of drug development for children. It has been written specifically to harmonize, promote, and facilitate high-quality and ethical clinical research for children within the ICH regions, i.e., the United States of America (USA), the European Union (EU), and Japan. This article details the various regulations applicable in each ICH region following the publication of the guideline. The framework of rewards, incentives, and obligations for pharmaceutical companies established for the development of pediatric drugs are compared. It appears that the USA and the EU have both developed specific regulations for pediatric drug development while Japan has not. However, in Japan, pharmaceutical companies (PCs) are encouraged to develop pediatric drugs voluntarily, and they may be granted additional months of market exclusivity or the postponement of the drug re-examination deadline. In both the USA and the EU, regulations aimed to increase the number of clinical studies conducted in children, in order to ensure that the necessary data are generated, determining the conditions in which a drug may be authorized to treat the pediatric population. PCs are encouraged to develop pediatric assessment, including pediatric clinical trials, which is described in a pediatric plan submitted to the relevant authorities. A system of rewards for PCs submitting an application for marketing authorization containing pediatric use information has been put in place to cover the additional investment for testing drugs in children. Subject to conditions, these rewards consist in a 6-month extension of the patent or supplementary protection. Regarding the approval for new medicinal products in these two regions, regulations require PCs to include, when it is relevant, a pediatric assessment in their drug research and development plan, which must be approved. Although these regions have implemented the ICH guideline, the regulation differs with respect to the timing of studies in children relative to adults and approval of a pediatric drug development plan. Except for special cases, the pediatric investigation plan in the EU is required to be prepared and submitted to the competent authorities upon availability of adult pharmacokinetic studies (after phase I), which means at an early phase of a new drug development plan. In the USA, the pediatric plan is requested later during the phase II or III trials. In practice, it has become difficult for pharmaceutical industries to develop a practicable clinical program for pediatrics including timelines for studies in children that satisfy both EU and USA authorities. Nevertheless, at an early stage of the development strategy, direct support and advice from competent authorities can be obtained. For the ICH regions, pediatric committees are well-established albeit less structured in Japan. Their roles are to review and assess pediatric plans, to issue recommendations, to advise pharmaceutical companies on the content and format of pediatric data to be methodically collected and analyzed, and to avoid exposing children to unnecessary or redundant clinical trials. This regulatory framework encourages the study and the development of pediatric drugs, but it is still quite difficult to actually measure the impact of the ICH E11 on increasing the number of drugs for pediatric use. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
Hydroxyurea-Mediated Cytotoxicity Without Inhibition of Ribonucleotide Reductase.
Liew, Li Phing; Lim, Zun Yi; Cohen, Matan; Kong, Ziqing; Marjavaara, Lisette; Chabes, Andrei; Bell, Stephen D
2016-11-01
In many organisms, hydroxyurea (HU) inhibits class I ribonucleotide reductase, leading to lowered cellular pools of deoxyribonucleoside triphosphates. The reduced levels for DNA precursors is believed to cause replication fork stalling. Upon treatment of the hyperthermophilic archaeon Sulfolobus solfataricus with HU, we observe dose-dependent cell cycle arrest, accumulation of DNA double-strand breaks, stalled replication forks, and elevated levels of recombination structures. However, Sulfolobus has a HU-insensitive class II ribonucleotide reductase, and we reveal that HU treatment does not significantly impact cellular DNA precursor pools. Profiling of protein and transcript levels reveals modulation of a specific subset of replication initiation and cell division genes. Notably, the selective loss of the regulatory subunit of the primase correlates with cessation of replication initiation and stalling of replication forks. Furthermore, we find evidence for a detoxification response induced by HU treatment. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.
Furuya, Kanji; Takahashi, Kohta; Yanagida, Mitsuhiro
1998-01-01
The loss of sister chromatid cohesion triggers anaphase spindle movement. The budding yeast Mcd1/Scc1 protein, called cohesin, is required for associating chromatids, and proteins homologous to it exist in a variety of eukaryotes. Mcd1/Scc1 is removed from chromosomes in anaphase and degrades in G1. We show that the fission yeast protein, Mis4, which is required for equal sister chromatid separation in anaphase is a different chromatid cohesion molecule that behaves independent of cohesin and is conserved from yeast to human. Its inactivation in G1 results in cell lethality in S phase and subsequent premature sister chromatid separation. Inactivation in G2 leads to cell death in subsequent metaphase–anaphase progression but missegregation occurs only in the next round of mitosis. Mis4 is not essential for condensation, nor does it degrade in G1. Rather, it associates with chromosomes in a punctate fashion throughout the cell cycle. mis4 mutants are hypersensitive to hydroxyurea (HU) and UV irradiation but retain the ability to restrain cell cycle progression when damaged or sustaining a block to replication. The mis4 mutation results in synthetic lethality with a DNA ligase mutant. Mis4 may form a stable link between chromatids in S phase that is split rather than removed in anaphase. PMID:9808627
Schizosaccharomyces pombe Hsk1p Is a Potential Cds1p Target Required for Genome Integrity
Snaith, Hilary A.; Brown, Grant W.; Forsburg, Susan L.
2000-01-01
The fission yeast Hsk1p kinase is an essential activator of DNA replication. Here we report the isolation and characterization of a novel mutant allele of the gene. Consistent with its role in the initiation of DNA synthesis, hsk1ts genetically interacts with several S-phase mutants. At the restrictive temperature, hsk1ts cells suffer abnormal S phase and loss of nuclear integrity and are sensitive to both DNA-damaging agents and replication arrest. Interestingly, hsk1ts mutants released to the restrictive temperature after early S-phase arrest in hydroxyurea (HU) are able to complete bulk DNA synthesis but they nevertheless undergo an abnormal mitosis. These findings indicate a second role for hsk1 subsequent to HU arrest. Consistent with a later S-phase role, hsk1ts is synthetically lethal with Δrqh1 (RecQ helicase) or rad21ts (cohesin) mutants and suppressed by Δcds1 (RAD53 kinase) mutants. We demonstrate that Hsk1p undergoes Cds1p-dependent phosphorylation in response to HU and that it is a direct substrate of purified Cds1p kinase in vitro. These results indicate that the Hsk1p kinase is a potential target of Cds1p regulation and that its activity is required after replication initiation for normal mitosis. PMID:11027263
Pediatric thermal injury: acute care and reconstruction update.
Armour, Alexis D; Billmire, David A
2009-07-01
The acute and reconstructive care of each pediatric burn patient presents unique challenges to the plastic surgeon and the burn care team. : The purpose of this review article is to highlight the interdependence between the acute and reconstructive needs of pediatric burn patients as it pertains to each anatomical site. Relevant principles of acute pediatric burn care and burn reconstruction are outlined, based on the authors' experience and review of the literature. The need for late reconstruction in pediatric burn survivors is significantly influenced by the acute surgical and rehabilitative treatments. With their vulnerability to airway swelling, hypothermia, pulmonary edema, and ischemia-reperfusion injury, pediatric patients with large burns require precise, life-saving treatment in the acute phase. Decision-making in pediatric burn reconstruction must take into account the patient's future growth, maturity, and often lack of suitable donor sites. Appropriately selected reconstructive techniques are essential to optimize function, appearance, and quality of life in pediatric burn survivors.
Cell cycle G2/M arrest through an S phase-dependent mechanism by HIV-1 viral protein R.
Li, Ge; Park, Hyeon U; Liang, Dong; Zhao, Richard Y
2010-07-07
Cell cycle G2 arrest induced by HIV-1 Vpr is thought to benefit viral proliferation by providing an optimized cellular environment for viral replication and by skipping host immune responses. Even though Vpr-induced G2 arrest has been studied extensively, how Vpr triggers G2 arrest remains elusive. To examine this initiation event, we measured the Vpr effect over a single cell cycle. We found that even though Vpr stops the cell cycle at the G2/M phase, but the initiation event actually occurs in the S phase of the cell cycle. Specifically, Vpr triggers activation of Chk1 through Ser345 phosphorylation in an S phase-dependent manner. The S phase-dependent requirement of Chk1-Ser345 phosphorylation by Vpr was confirmed by siRNA gene silencing and site-directed mutagenesis. Moreover, downregulation of DNA replication licensing factors Cdt1 by siRNA significantly reduced Vpr-induced Chk1-Ser345 phosphorylation and G2 arrest. Even though hydroxyurea (HU) and ultraviolet light (UV) also induce Chk1-Ser345 phosphorylation in S phase under the same conditions, neither HU nor UV-treated cells were able to pass through S phase, whereas vpr-expressing cells completed S phase and stopped at the G2/M boundary. Furthermore, unlike HU/UV, Vpr promotes Chk1- and proteasome-mediated protein degradations of Cdc25B/C for G2 induction; in contrast, Vpr had little or no effect on Cdc25A protein degradation normally mediated by HU/UV. These data suggest that Vpr induces cell cycle G2 arrest through a unique molecular mechanism that regulates host cell cycle regulation in an S-phase dependent fashion.
Barbui, Tiziano; Barosi, Giovanni; Birgegard, Gunnar; Cervantes, Francisco; Finazzi, Guido; Griesshammer, Martin; Harrison, Claire; Hasselbalch, Hans Carl; Hehlmann, Rudiger; Hoffman, Ronald; Kiladjian, Jean-Jacques; Kröger, Nicolaus; Mesa, Ruben; McMullin, Mary F; Pardanani, Animesh; Passamonti, Francesco; Vannucchi, Alessandro M; Reiter, Andreas; Silver, Richard T; Verstovsek, Srdan; Tefferi, Ayalew
2011-02-20
We present a review of critical concepts and produce recommendations on the management of Philadelphia-negative classical myeloproliferative neoplasms, including monitoring, response definition, first- and second-line therapy, and therapy for special issues. Key questions were selected according the criterion of clinical relevance. Statements were produced using a Delphi process, and two consensus conferences involving a panel of 21 experts appointed by the European LeukemiaNet (ELN) were convened. Patients with polycythemia vera (PV) and essential thrombocythemia (ET) should be defined as high risk if age is greater than 60 years or there is a history of previous thrombosis. Risk stratification in primary myelofibrosis (PMF) should start with the International Prognostic Scoring System (IPSS) for newly diagnosed patients and dynamic IPSS for patients being seen during their disease course, with the addition of cytogenetics evaluation and transfusion status. High-risk patients with PV should be managed with phlebotomy, low-dose aspirin, and cytoreduction, with either hydroxyurea or interferon at any age. High-risk patients with ET should be managed with cytoreduction, using hydroxyurea at any age. Monitoring response in PV and ET should use the ELN clinicohematologic criteria. Corticosteroids, androgens, erythropoiesis-stimulating agents, and immunomodulators are recommended to treat anemia of PMF, whereas hydroxyurea is the first-line treatment of PMF-associated splenomegaly. Indications for splenectomy include symptomatic portal hypertension, drug-refractory painful splenomegaly, and frequent RBC transfusions. The risk of allogeneic stem-cell transplantation-related complications is justified in transplantation-eligible patients whose median survival time is expected to be less than 5 years.
Barbui, Tiziano; Barosi, Giovanni; Birgegard, Gunnar; Cervantes, Francisco; Finazzi, Guido; Griesshammer, Martin; Harrison, Claire; Hasselbalch, Hans Carl; Hehlmann, Rudiger; Hoffman, Ronald; Kiladjian, Jean-Jacques; Kröger, Nicolaus; Mesa, Ruben; McMullin, Mary F.; Pardanani, Animesh; Passamonti, Francesco; Vannucchi, Alessandro M.; Reiter, Andreas; Silver, Richard T.; Verstovsek, Srdan; Tefferi, Ayalew
2011-01-01
We present a review of critical concepts and produce recommendations on the management of Philadelphia-negative classical myeloproliferative neoplasms, including monitoring, response definition, first- and second-line therapy, and therapy for special issues. Key questions were selected according the criterion of clinical relevance. Statements were produced using a Delphi process, and two consensus conferences involving a panel of 21 experts appointed by the European LeukemiaNet (ELN) were convened. Patients with polycythemia vera (PV) and essential thrombocythemia (ET) should be defined as high risk if age is greater than 60 years or there is a history of previous thrombosis. Risk stratification in primary myelofibrosis (PMF) should start with the International Prognostic Scoring System (IPSS) for newly diagnosed patients and dynamic IPSS for patients being seen during their disease course, with the addition of cytogenetics evaluation and transfusion status. High-risk patients with PV should be managed with phlebotomy, low-dose aspirin, and cytoreduction, with either hydroxyurea or interferon at any age. High-risk patients with ET should be managed with cytoreduction, using hydroxyurea at any age. Monitoring response in PV and ET should use the ELN clinicohematologic criteria. Corticosteroids, androgens, erythropoiesis-stimulating agents, and immunomodulators are recommended to treat anemia of PMF, whereas hydroxyurea is the first-line treatment of PMF-associated splenomegaly. Indications for splenectomy include symptomatic portal hypertension, drug-refractory painful splenomegaly, and frequent RBC transfusions. The risk of allogeneic stem-cell transplantation–related complications is justified in transplantation-eligible patients whose median survival time is expected to be less than 5 years. PMID:21205761
DOE Office of Scientific and Technical Information (OSTI.GOV)
Siegel, P.D.
1988-01-01
The present study utilized NO{sub 2} to fingerprint the biochemical reaction of the pulmonary compartment to oxidative damage and to correlate this with histopathology following acute and subacute exposures to NO{sub 2}. Acute exposure to NO{sub 2} produced dose-dependent immediate increases in the nonenzymatic parameters of pulmonary protein content, protease inhibitor activity and lung weight. The enzymatic activities of lactate dehydrogenase (LDH), choline kinase and beta-glucuronidase were elevated by two days following acute exposure. All of the above parameters were elevated following subacute exposure, however, nonenzymatic manifestations were attenuated with respect to enzymatic alterations. Hydroxyurea-induced granulocytopenia attenuated the increases inmore » activities of LDH and beta-glucuronidase following acute, but not subacute exposures. Cycloheximide-induced protein synthesis inhibition decrease the LDH and beta-glucuronidase response to NO{sub 2} without altering the increases in protein content or protease inhibitor activity.« less
Yasumoto, Sawa; Ohtsuka, Yoko; Sato, Katsuaki; Kurata, Atsuyo; Numachi, Yotaro; Shimizu, Masahiro
2018-05-31
To investigate the efficacy and safety of long-term lamotrigine (LTG) monotherapy in Japanese and South Korean pediatric patients with newly diagnosed typical absence seizures. Six Japanese patients and one South Korean patient were enrolled in the extension phase of the study after completing the 12-week maintenance phase of an open-label clinical study of LTG monotherapy. During the extension phase, patients underwent efficacy and safety evaluation every 12 weeks. Of the seven patients, six patients completed the extension phase. The seizure-free rate confirmed by hyperventilation (HV)-electroencephalography ranged from 71.4% to 100.0% at each visit up to Week 168 of the extension phase. Similar effects were confirmed by HV-clinical signs and seizure diaries. Although no unexpected adverse events were observed, one Japanese patient was withdrawn from the extension phase due to mild drug-related rash developed 842 days after the start of LTG. Although the number of patients is limited, long-term LTG monotherapy appeared to be effective and generally well tolerated in Japanese and South Korean pediatric patients with typical absence seizures. Copyright © 2018 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.
Blood transfusion for preventing primary and secondary stroke in people with sickle cell disease.
Wang, Winfred C; Dwan, Kerry
2013-11-14
In sickle cell disease, a common inherited haemoglobin disorder, abnormal haemoglobin distorts red blood cells, causing anaemia, vaso-occlusion and dysfunction in most body organs. Without intervention, stroke affects around 10% of children with sickle cell anaemia (HbSS) and recurrence is likely. Chronic blood transfusion dilutes the sickled red blood cells, reducing the risk of vaso-occlusion and stroke. However, side effects can be severe. To assess risks and benefits of chronic blood transfusion regimens in people with sickle cell disease to prevent first stroke or recurrences. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register, comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and conference proceedings.Date of the latest search of the Group's Haemoglobinopathies Trials Register: 28 January 2013. Randomised and quasi-randomised controlled trials comparing blood transfusion as prophylaxis for stroke in people with sickle cell disease to alternative or no treatment. Both authors independently assessed the risk of bias of the included trials and extracted data. Searches identified three eligible randomised trials (n = 342). The first two trials addressed the use of chronic transfusion to prevent primary stroke; the third utilized the drug hydroxycarbamide (hydroxyurea) and phlebotomy to prevent both recurrent (secondary) stroke and iron overload in patients who had already experienced an initial stroke. In the first trial (STOP) a chronic transfusion regimen for maintaining sickle haemoglobin lower than 30% was compared with standard care in 130 children with sickle cell disease judged (through transcranial Doppler ultrasonography) as high-risk for first stroke. During the trial, 11 children in the standard care group suffered a stroke compared to one in the transfusion group, odds ratio 0.08 (95% confidence interval 0.01 to 0.66). This meant the trial was terminated early. The transfusion group had a high complications rate, including iron overload, alloimmunisation, and transfusion reactions. The second trial (STOP II) investigated risk of stroke when transfusion was stopped after at least 30 months in this population. The trial closed early due to a significant difference in risk of stroke between participants who stopped transfusion and those who continued as measured by reoccurrence of abnormal velocities on Doppler examination or the occurrence of overt stroke in the group that stopped transfusion. The third trial (SWiTCH) was a non-inferiority trial comparing transfusion and iron chelation (standard management) with hydroxyurea and phlebotomy (alternative treatment) with the combination endpoint of prevention of stroke recurrence and reduction of iron overload. This trial was stopped early after enrolment and follow up of 133 children because of analysis showing futility in reaching the composite primary endpoint. The stroke rate (seven strokes on hydroxyurea and phlebotomy, none on transfusion and chelation, odds ratio 16.49 (95% confidence interval 0.92 to 294.84)) was within the non-inferiority margin, but the liver iron content was not better in the alternative arm. The STOP trial demonstrated a significantly reduced risk of stroke in participants with abnormal transcranial Doppler ultrasonography velocities receiving regular blood transfusions. The follow-up trial (STOP 2) indicated that individuals may revert to former risk status if transfusion is discontinued. The degree of risk must be balanced against the burden of chronic transfusions. The combination of hydroxyurea and phlebotomy is not as effective as "standard" transfusion and chelation in preventing secondary stroke and iron overload. Ongoing multicentre trials are investigating the use of chronic transfusion to prevent silent infarcts, the use of hydroxyurea as an alternative to transfusion in children with abnormal transcranial Doppler ultrasonography velocities, and the use of hydroxyurea to prevent conversion of transcranial Doppler ultrasonography velocities from conditional (borderline) to abnormal values.
Wattier, Rachel L; Levy, Emily R; Sabnis, Amit J; Dvorak, Christopher C; Auerbach, Andrew D
2017-09-01
OBJECTIVE To evaluate interventions to reduce avoidable antibiotic use on pediatric oncology and hematopoietic stem cell transplantation (HSCT) services. DESIGN Interrupted time series. SETTING Academic pediatric hospital with separate oncology and HSCT services. PARTICIPANTS Children admitted to the services during baseline (October 2011-August 2013) and 2 intervention periods, September 2013-June 2015 and July 2015-June 2016, including 1,525 oncology hospitalizations and 301 HSCT hospitalizations. INTERVENTION In phase 1, we completed an update of the institutional febrile neutropenia (FN) guideline for the pediatric oncology service, recommending first-line β-lactam monotherapy rather than routine use of 2 gram-negative agents. Phase 2 included updating the HSCT service FN guideline and engagement with a new pediatric antimicrobial stewardship program. The use of target antibiotics (tobramycin and ciprofloxacin) was measured in days of therapy per 1,000 patient days collected from administrative data. Intervention effects were evaluated using interrupted time series with segmented regression. RESULTS Phase 1 had mixed effects-long-term reduction in tobramycin use (97% below projected at 18 months) but rebound with increasing slope in ciprofloxacin use (+18% per month). Following phase 2, tobramycin and ciprofloxacin use on the oncology service were both 99% below projected levels at 12 months. On the HSCT service, tobramycin use was 99% below the projected level and ciprofloxacin use was 96% below the projected level at 12 months. CONCLUSIONS Locally adapted guidelines can facilitate practice changes in oncology and HSCT settings. More comprehensive and ongoing interventions, including follow-up education, feedback, and engagement of companion services may be needed to sustain changes. Infect Control Hosp Epidemiol 2017;38:1039-1047.
Bertoldi, Julia; Ferreira, Aline; Scancetti, Luiza; Padilha, Patricia
2018-01-01
Quality indicators for nutritional therapy (QINT) are important in assessing care and monitoring of resources. Among the 30 indicators proposed by International Life Sciences Institute, Brazil, there is still no evaluation of the most pertinent for Pediatrics. To list the 10 main quality indicators for nutritional therapies (QINTs) for Pediatrics. This was a two-phase cross-sectional study. Firstly, a questionnaire was answered by physicians, nutritionists, nurses, and pharmacists, all with having experience in nutritional therapy (NT) with Pediatrics, in Rio de Janeiro, Brazil. Participants assessed four attributes of QINT by using the Likert scale. A Top 10 ranked QINT list for Pediatrics was established. To verify the consistency of the questionnaire, Cronbach's Alpha coefficient was calculated. Secondly, the opinions of the participants on the results that were obtained were requested and the percentages of the positive responses were calculated. A total of 33 professionals participated in the first phase and 92% ( n = 23 of 25) in the second phase approved the results of the selected indicators. Among the Top 10 QINTs, the three main ones were: #1: "Frequency of diarrhea in those patients on enteral nutrition" (mean = 13.194; α = 0.827); #2: "Frequency of dietary nutritional prescriptions upon the hospital discharge of the NT patients" (mean = 12.871; α = 0.822); #3: "Frequency of the NT patients who recovered their oral intake" (mean = 12.839; α = 0.859). When considering the consistency and the concordance that were obtained, it can be suggested that the list of Top 10 QINTs as proposed in this study will help in the evaluation of NT quality indicators for Pediatrics.
Translation of alcohol screening and brief intervention guidelines to pediatric trauma centers.
Mello, Michael J; Bromberg, Julie; Baird, Janette; Nirenberg, Ted; Chun, Thomas; Lee, Christina; Linakis, James G
2013-10-01
As part of the American College of Surgeons verification to be a Level 1 trauma center, centers are required to have the capacity to identify trauma patients with risky alcohol use and provide an intervention. Despite supporting scientific evidence and national policy statements encouraging alcohol Screening, Brief Intervention and Referral to Treatment (SBIRT), barriers still exist, which prevent the integration of SBIRT into clinical care. Study objectives of this multisite translational research study were to identify best practices for integrating SBIRT services into routine care for pediatric trauma patients, to measure changes in practice with adoption and implementation of a SBIRT policy, and to define barriers and opportunities for adoption and implementation of SBIRT services at pediatric trauma centers. This translational research study was conducted at seven US pediatric trauma centers during a 3-year period. Changes in SBIRT practice were measured through self-report and medical record review at three different study phases, namely, adoption, implementation, and maintenance phases. According to medical record review, at baseline, 11% of eligible patients were screened and received a brief intervention (if necessary) across all sites. After completion of the SBIRT technical assistance activities, all seven participating trauma centers had effectively developed, adopted, and implemented SBIRT policies for injured adolescent inpatients. Furthermore, across all sites, 73% of eligible patients received SBIRT services after both the implementation and maintenance phases. Opportunities and barriers for successful integration were identified. This model may serve as method for translating SBIRT services into practice within pediatric trauma centers.
2018-04-20
Leukemia; Leukemia,Pediatric; Leukemia, Myleiod; Leukemia, Mylegenous, Chronic; Leukemia, Mylegenous, Accelerated; BCR-ABL Positive; Myeloproliferative Disorder; Bone Marrow Disease; Hematologic Diseases; Neoplastic Processes; Imatinib; Dasatinib; Enzyme Inhibitor; Protein Kinase Inhibitor
Novel insights in the management of sickle cell disease in childhood
Iughetti, Lorenzo; Bigi, Elena; Venturelli, Donatella
2016-01-01
Sickle cell disease (SCD) is a life-threatening genetic disorder characterized by chronic hemolytic anemia, vascular injury and multiorgan dysfunctions. Over the last few decades, there have been significant improvements in SCD management in Western countries, especially in pediatric population. An early onset of prophylaxis with Penicillin and a proper treatment of the infections have increased the overall survival in childhood. Nevertheless, management of painful episodes and prevention of organ damage are still challenging and more efforts are needed to better understand the mechanisms behind the development of chronic organ damages. Hydroxyurea (Hydroxycarbamide, HU), the only medication approved as a disease-modifying agent by the United States Food and Drug Administration and the European Medicines Agency, is usually under-used, especially in developing countries. Currently, hematopoietic stem-cell transplantation is considered the only curative option, although its use is limited by lack of donors and transplant-related toxicity. SCD symptoms are similar in children and adults, but complications and systemic organ damages increase with age, leading to early mortality worldwide. Experts in comprehensive care of young patients with SCD, especially those approaching the transition age to adulthood, are missing, leading people to rely on urgent care, increasing health care utilization costs and inappropriate treatments. It would be important to establish programs of comprehensive healthcare for patients with SCD from birth to adulthood, to improve their quality and expectancy of life. PMID:26862499
Communicating and understanding the purpose of pediatric phase I cancer trials.
Cousino, Melissa K; Zyzanski, Stephen J; Yamokoski, Amy D; Hazen, Rebecca A; Baker, Justin N; Noll, Robert B; Rheingold, Susan R; Geyer, J Russell; Alexander, Stewart C; Drotar, Dennis; Kodish, Eric D
2012-12-10
Quality informed consent should provide a clear understanding of the purpose of the research. Given the ethical challenges of pediatric phase I cancer trials, it is important to investigate physician-parent communication during informed consent conferences (ICCs) and parental understanding of the purpose of these studies. In the multisite Informed Consent in Pediatric Phase I Cancer Trials study, 85 ICCs for phase I research between June 2008 and May 2011 were directly observed, and 60 parents were subsequently interviewed. The scientific purpose was defined as composite understanding of drug safety, dose finding, and dose escalation. We determined the frequency with which physicians explained these and other phase I-related concepts during the ICC. Parent interviews were analyzed to determine understanding. The child was present at 83 of 85 ICCs. Only 32% of parents demonstrated substantial understanding of the scientific purpose of phase I cancer trials; 35% demonstrated little or no understanding. Parents of higher socioeconomic status and racial majority status were more likely to understand the scientific purpose. Factors associated with understanding included physician explanation of the goal of the applicable phase I protocol offered (explained in 85% of ICCs) and explanation of the dose cohorts (explained in 43% of ICCs). Physicians explained drug safety in 23% of ICCs, dose finding in 52% of ICCs, and dose escalation in 53% of ICCs. Many parents of children participating in phase I trials do not understand the purpose of these trials. Physician-parent communication about the purpose of phase I research is lacking during ICCs.
Distinct RAD51 Associations with RAD52 and BCCIP in Response to DNA Damage and Replication Stress
Wray, Justin; Liu, Jingmei; Nickoloff, Jac A.; Shen, Zhiyuan
2009-01-01
RAD51 has critical roles in homologous recombination (HR) repair of DNA double-strand breaks (DSB) and restarting stalled or collapsed replication forks. In yeast, Rad51 function is facilitated by Rad52 and other “mediators.” Mammalian cells express RAD52, but BRCA2 may have supplanted RAD52 in mediating RAD51 loading onto ssDNA. BCCIP interacts with BRCA2, and both proteins are important for RAD51 focus formation after ionizing radiation and HR repair of DSBs. Nonetheless, mammalian RAD52 shares biochemical activities with yeast Rad52, including RAD51 binding and single-strand annealing, suggesting a conserved role in HR. Because RAD52 and RAD51 associate, and RAD51 and BCCIP associate, we investigated the colocalization of RAD51 with BCCIP and RAD52 in human cells. We found that RAD51 colocalizes with BCCIP early after ionizing radiation, with RAD52 later, and there was little colocalization of BCCIP and RAD52. RAD52 foci are induced to a greater extent by hydroxyurea, which stalls replication forks, than by ionizing radiation. Using fluorescence recovery after photo bleaching, we show that RAD52 mobility is reduced to a greater extent by hydroxyurea than ionizing radiation. However, BCCIP showed no changes in mobility after hydroxyurea or ionizing radiation. We propose that BCCIP-dependent repair of DSBs by HR is an early RAD51 response to ionizing radiation–induced DNA damage, and that RAD52-dependent HR occurs later to restart a subset of blocked or collapsed replication forks. RAD52 and BRCA2 seem to act in parallel pathways, suggesting that targeting RAD52 in BRCA2-deficient tumors may be effective in treating these tumors. PMID:18413737
A mutated dph3 gene causes sensitivity of Schizosaccharomyces pombe cells to cytotoxic agents.
Villahermosa, Desirée; Knapp, Karen; Fleck, Oliver
2017-12-01
Dph3 is involved in diphthamide modification of the eukaryotic translation elongation factor eEF2 and in Elongator-mediated modifications of tRNAs, where a 5-methoxycarbonyl-methyl moiety is added to wobble uridines. Lack of such modifications affects protein synthesis due to inaccurate translation of mRNAs at ribosomes. We have discovered that integration of markers at the msh3 locus of Schizosaccharomyces pombe impaired the function of the nearby located dph3 gene. Such integrations rendered cells sensitive to the cytotoxic drugs hydroxyurea and methyl methanesulfonate. We constructed dph3 and msh3 strains with mutated ATG start codons (ATGmut), which allowed investigating drug sensitivity without potential interference by marker insertions. The dph3-ATGmut and a dph3::loxP-ura4-loxM gene disruption strain, but not msh3-ATGmut, turned out to be sensitive to hydroxyurea and methyl methanesulfonate, likewise the strains with cassettes integrated at the msh3 locus. The fungicide sordarin, which inhibits diphthamide modified eEF2 of Saccharomyces cerevisiae, barely affected survival of wild type and msh3Δ S. pombe cells, while the dph3Δ mutant was sensitive. The msh3-ATG mutation, but not dph3Δ or the dph3-ATG mutation caused a defect in mating-type switching, indicating that the ura4 marker at the dph3 locus did not interfere with Msh3 function. We conclude that Dph3 is required for cellular resistance to the fungicide sordarin and to the cytotoxic drugs hydroxyurea and methyl methanesulfonate. This is likely mediated by efficient translation of proteins in response to DNA damage and replication stress.
Lopes, Flavia C. M.; Traina, Fabiola; Almeida, Camila B.; Leonardo, Flavia C.; Franco-Penteado, Carla F.; Garrido, Vanessa T.; Colella, Marina P.; Soares, Raquel; Olalla-Saad, Sara T.; Costa, Fernando F.; Conran, Nicola
2015-01-01
As hypoxia-induced inflammatory angiogenesis may contribute to the manifestations of sickle cell disease, we compared the angiogenic molecular profiles of plasma from sickle cell disease individuals and correlated these with in vitro endothelial cell-mediated angiogenesis-stimulating activity and in vivo neovascularization. Bioplex demonstrated that plasma from patients with steady-state sickle cell anemia contained elevated concentrations of pro-angiogenic factors (angiopoietin-1, basic fibroblast growth factor, vascular endothelial growth factor, vascular endothelial growth factor-D and placental growth factor) and displayed potent pro-angiogenic activity, significantly increasing endothelial cell proliferation, migration and capillary-like structure formation. In vivo neovascularization of Matrigel plugs was significantly greater in sickle cell disease mice than in non-sickle cell disease mice, consistent with an up-regulation of angiogenesis in the disease. In plasma from patients with hemoglobin SC disease without proliferative retinopathy, anti-angiogenic endostatin and thrombospondin-2 were significantly elevated. In contrast, plasma from hemoglobin SC individuals with proliferative retinopathy had a pro-angiogenic profile and more significant effects on endothelial cell proliferation and capillary formation than plasma from patients without retinopathy. Hydroxyurea therapy was associated with significant reductions in plasma angiogenic factors and inhibition of endothelial cell-mediated angiogenic mechanisms and neovascularization. Thus, individuals with sickle cell anemia or hemoglobin SC disease with retinopathy present a highly angiogenic circulating milieu, capable of stimulating key endothelial cell-mediated angiogenic mechanisms. Combination anti-angiogenic therapy to prevent the progression of unregulated neovascularization and associated manifestations in sickle cell disease, such as pulmonary hypertension, may be indicated; furthermore, the benefits and drawbacks of the potent anti-angiogenic effects of hydroxyurea should be clarified. PMID:25769545
Elalfy, Mohsen S; Adly, Amira A M; Ismail, Eman A; Elhenawy, Yasmine I; Elghamry, Islam R
2013-12-01
To assess the efficacy and safety of combined hydroxyurea (HU) and recombinant human erythropoietin (rHuEPO) in β-thalassemia intermedia (TI) patients compared with single HU therapy. An interventional prospective randomized study registered in the ClinicalTrials.gov (NCT01624038) was performed on 80 TI patients (≤ 18 yr) divided into group A (40 patients received combined HU and rHuEPO) and group B (40 patients received single HU therapy). Baseline serum EPO levels were measured, and both groups were followed up for a mean period of 1 yr with regular assessment of transfusion requirements, blood pressure, ferritin, liver and renal functions, hemoglobin, and HbF. Quality of life (QoL) was assessed at the start and end of the study. Transfusion frequency and index were significantly decreased, while QoL was increased in group A compared with group B where 85% of patients showed improvement on combined therapy compared with 50% of patients on HU. Hemoglobin and HbF were significantly increased in both TI groups; however, this was more evident in group A than in group B. Also, 37.5% of patients in group A became transfusion-independent compared with 15% in group B. EPO levels were negatively related to increments of hemoglobin and HbF. Splenectomized patients and those with initial HbF% >40% had the best response to combined therapy. No serious adverse events necessitating discontinuation of therapy in both groups. HU was effective in management of TI; however, combination with rHuEPO gave a superior therapeutic effect resulting in the best clinical and hematological responses without adverse events. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Badawy, Sherif M; Thompson, Alexis A; Liem, Robert I
2016-05-01
Hydroxyurea is the only Food and Drug Administration approved medication for sickle cell disease (SCD) with short- and long-term benefits for both morbidity and mortality. However, hydroxyurea underutilization and adherence remain challenges for patients with SCD. The objectives of this study were to determine access to technology among adolescents and young adults (AYA) with SCD and to identify their preferred technology-based strategies for improving medication adherence. A cross-sectional survey was administered in a variety of clinical settings from October 2014 through May 2015 to AYA (12-22 years) with SCD (all genotypes) followed in a Comprehensive Sickle Cell Program. Eighty of 107 eligible participants completed the survey for a 75% response rate. Participants (51% female, 94% Black) had a mean age of 15.3 ± 2.8 years. Most participants (75%) were on a daily medication with about half on hydroxyurea. Forgetfulness (67%) was the most common barrier to medication adherence. The majority of participants (85%) owned smartphones and either owned or had access to electronic tablets (83%), laptops (72%), or desktops (70%). Of the proposed smartphone app features, daily medication reminders were ranked first most frequently, followed by education about SCD, adherence text prompts, education about SCD medications, and medication log. The majority of our AYA with SCD owned smartphones and had access to other electronic devices. Our survey results provided valuable insight into the preferred app features and optimal strategies for developing technology-based interventions, such as a multicomponent app, to increase medication adherence for AYA with SCD or other chronic conditions. © 2016 Wiley Periodicals, Inc.
The mammalian INO80 chromatin remodeling complex is required for replication stress recovery
Vassileva, Ivelina; Yanakieva, Iskra; Peycheva, Michaela; Gospodinov, Anastas; Anachkova, Boyka
2014-01-01
A number of studies have implicated the yeast INO80 chromatin remodeling complex in DNA replication, but the function of the human INO80 complex during S phase remains poorly understood. Here, we have systematically investigated the involvement of the catalytic subunit of the human INO80 complex during unchallenged replication and under replication stress by following the effects of its depletion on cell survival, S-phase checkpoint activation, the fate of individual replication forks, and the consequences of fork collapse. We report that INO80 was specifically needed for efficient replication elongation, while it was not required for initiation of replication. In the absence of the Ino80 protein, cells became hypersensitive to hydroxyurea and displayed hyperactive ATR-Chk1 signaling. Using bulk and fiber labeling of DNA, we found that cells deficient for Ino80 and Arp8 had impaired replication restart after treatment with replication inhibitors and accumulated double-strand breaks as evidenced by the formation of γ-H2AX and Rad51 foci. These data indicate that under conditions of replication stress mammalian INO80 protects stalled forks from collapsing and allows their subsequent restart. PMID:25016522
Han, Qiaoyan; Sun, Miao; Wu, Lingyu; Chen, Jing; Wang, Wei; Liu, Chunhua; Chen, Haoyue; Du, Guibin
2014-04-01
Post-transplant lymphoproliferative disorders originating from T lymphocytes are a rare complication of allogeneic haematopoietic stem cell transplantation (allo-HSCT) that are not usually associated with Epstein-Barr virus infection. A male patient diagnosed at the age of 15 years with chronic myeloid leukaemia (in the chronic phase) was initially treated with oral hydroxyurea. The disease entered an accelerated phase when the patient was 22 years old. Complete remission was achieved after one course of homoharringtonine and cytarabine. The patient then underwent human leucocyte antigen-matched sibling donor allo-HSCT. Just over 6.5 years after the allo-HSCT, a second primary tumour was located in the distal femur and diagnosed as T-cell non-Hodgkin's lymphoma (stage IV, group B). This was treated with various chemotherapy and radiotherapy regimens, but the outcomes were poor and the disease progressed. The T-cell lymphoma invaded many sites, including the skeleton, spleen and skin, and the patient died within 8 months of the diagnosis. This current case report highlights the need for the early detection and prevention of subsequent primary malignancies after allo-HSCT.
Interventions for chronic kidney disease in people with sickle cell disease
Roy, Noemi BA; Fortin, Patricia M; Bull, Katherine R; Doree, Carolyn; Trivella, Marialena; Hopewell, Sally; Estcourt, Lise J
2017-01-01
Background Sickle cell disease (SCD) is one of the commonest severe monogenic disorders in the world, due to the inheritance of two abnormal haemoglobin (beta-globin) genes. SCD can cause severe pain, significant end-organ damage, pulmonary complications, and premature death. Kidney disease is a frequent and potentially severe complication in people with SCD. Chronic kidney disease is defined as abnormalities of kidney structure or function, present for more than three months. Sickle cell nephropathy refers to the spectrum of kidney complications in SCD. Glomerular damage is a cause of microalbuminuria and can develop at an early age in children with SCD, and increases in prevalence in adulthood. In people with sickle cell nephropathy, outcomes are poor as a result of the progression to proteinuria and chronic kidney insufficiency. Up to 12% of people who develop sickle cell nephropathy will develop end-stage renal disease. Objectives To assess the effectiveness of any intervention in preventing or reducing kidney complications or chronic kidney disease in people with SCD (including red blood cell transfusions, hydroxyurea and angiotensin-converting enzyme inhibitor (ACEI)), either alone or in combination with each other. Search methods We searched for relevant trials in the Cochrane Library, MEDLINE (from 1946), Embase (from 1974), the Transfusion Evidence Library (from 1980), and ongoing trial databases; all searches current to 05 April 2016. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register: 13 April 2017. Selection criteria Randomised controlled trials comparing interventions to prevent or reduce kidney complications or chronic kidney disease in people with SCD. There were no restrictions by outcomes examined, language or publication status. Data collection and analysis Two authors independently assessed trial eligibility, extracted data and assessed the risk of bias. Main results We included two trials with 215 participants. One trial was published in 2011 and included 193 children aged 9 months to 18 months, and compared treatment with hydroxyurea to placebo. The second trial was published in 1998 and included 22 adults with normal blood pressure and microalbuminuria and compared ACEI to placebo. We rated the quality of evidence as low to very low across different outcomes according to GRADE methodology. This was due to trials having: a high or unclear risk of bias including attrition and detection bias; indirectness (the available evidence was for children aged 9 months to 18 months in one trial and a small and select adult sample size in a second trial); and imprecise outcome effect estimates of significant benefit or harm. Hydroxyurea versus placebo We are very uncertain if hydroxyurea reduces or prevents progression of kidney disease (assessed by change in glomerular filtration rate), or reduces hyperfiltration in children aged 9 to 18 months, mean difference (MD) 0.58 (95% confidence interval (CI) -14.60 to 15.76 (mL/min per 1.73 m2)) (one study; 142 participants; very low-quality evidence). In children aged 9 to 18 months, hydroxyurea may improve the ability to concentrate urine, MD 42.23 (95% CI 12.14 to 72.32 (mOsm/kg)) (one study; 178 participants; low-quality evidence). Hydroxyurea may make little or no difference to SCD-related serious adverse events including: incidence of acute chest syndrome, risk ratio (RR) 0.39 (99% CI 0.13 to 1.16); painful crisis, RR 0.68 (99% CI 0.45 to 1.02); and hospitalisations, RR 0.83 (99% CI 0.68 to 1.01) (one study, 193 participants; low-quality evidence). No deaths occurred in the trial. Quality of life was not reported. ACEI versus placebo We are very uncertain if ACEI reduces proteinuria in adults with SCD who have normal blood pressure and microalbuminuria, MD - 49.00 (95% CI -124.10 to 26.10 (mg per day)) (one study; 22 participants; very low-quality evidence). We are very uncertain if ACEI reduce or prevent kidney disease as measured by creatinine clearance. The authors state that creatinine clearance remained constant over six months in both groups, but no comparative data were provided (very low-quality evidence). All-cause mortality, serious adverse events and quality of life were not reported. Authors’ conclusions In young children aged 9 months to 18 months, we are very uncertain if hydroxyurea improves glomerular filtration rate or reduces hyperfiltration, but it may improve young children’s ability to concentrate urine and may make little or no difference on the incidence of acute chest syndrome, painful crises and hospitalisations. We are very uncertain if giving ACEI to adults with normal blood pressure and microalbuminuria has any effect on preventing or reducing kidney complications. This review identified no trials that looked at red cell transfusions nor any combinations of interventions to prevent or reduce kidney complications. Due to lack of evidence this review cannot comment on the management of either children aged over 18 months or adults with any known genotype of SCD. We have identified a lack of adequately-designed and powered studies, and no ongoing trials which address this critical question. Trials of hydroxyurea, ACEI or red blood cell transfusion in older children and adults are urgently needed to determine any effect on prevention or reduction kidney complications in people with SCD. PMID:28672087
Improvement of Pediatric Drug Development: Regulatory and Practical Frameworks.
Tsukamoto, Katusra; Carroll, Kelly A; Onishi, Taku; Matsumaru, Naoki; Brasseur, Daniel; Nakamura, Hidefumi
2016-03-01
A dearth in pediatric drug development often leaves pediatricians with no alternative but to prescribe unlicensed or off-label drugs with a resultant increased risk of adverse events. We present the current status of pediatric drug development and, based on our data analysis, clarify the problems in this area. Further action is proposed to improve the drug development that has pediatric therapeutic orphan status. We analyzed all Phase II/III and Phase III trials in ClinicalTrials.gov that only included pediatric participants (<18 years old) between 2006 and 2014. Performance index, an indicator of pediatric drug development, was calculated by dividing the annual number of pediatric clinical trials by million pediatric populations acquired from Census.gov. Effects of the 2 Japanese premiums introduced in 2010, for the enhancement of pediatric drug development, were analyzed by comparing mean performance index prepremiums (2006-2009) and postpremiums (2010-2014) among Japan, the European Union, and the United States. The European Union Clinical Trials Register and published reports from the European Medicines Agency were also surveyed to investigate the Paediatric Committee effect on pediatric clinical trials in the European Union. Mean difference of the performance index in prepremiums and postpremiums between Japan and the European Union were 0.296 (P < 0.001) and 0.066 (P = 0.498), respectively. Those between Japan and the United States were 0.560 (P < 0.001) and 0.281 (P = 0.002), indicating that pediatric drug development in Japan was more active after the introduction of these premiums, even reaching the level of the European Union. The Pediatric Regulation and the Paediatric Committee promoted pediatric drug development in the European Union. The registered number of clinical trials that includes at least 1 participants <18 years old in the European Union Clinical Trials Register increased by 247 trials (from 672) in the 1000 days after regulation. The ratio of pediatric clinical trials with an approved Paediatric Investigation Plan increased to >15% after 2008. Recruitment and ethical obstacles make conducting pediatric clinical trials challenging. An improved operational framework for conducting clinical trials should mirror the ever-improving regulatory framework that incentivizes investment in pediatric clinical trials. Technological approaches, enhancements in electronic medical record systems, and community approaches that actively incorporate input from physicians, researchers, and patients could offer a sustainable solution to recruitment of pediatric study participants. The key therefore is to improve pediatric pharmacotherapy collaboration among industry, government, academia, and community. Expanding the regulatory steps taken in the European Union, United States, and Japan and using innovative clinical trial tools can move pediatric pharmacotherapy out of its current therapeutic orphan state. Copyright © 2016 Elsevier HS Journals, Inc. All rights reserved.
Guzauskas, Gregory F; Villa, Kathleen F; Vanhove, Geertrui F; Fisher, Vicki L; Veenstra, David L
2017-03-01
To estimate the risk-benefit trade-off of a pediatric-inspired regimen versus hyperfractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone (hyper-CVAD) for first-line treatment of adolescents/young adult (AYA; ages 16-39 years) patients with Philadelphia-negative acute lymphoblastic leukemia. Patient outcomes were simulated using a 6-state Markov model, including complete response (CR), no CR, first relapse, second CR, second relapse, and death. A Weibull distribution was fit to the progression-free survival curve of hyper-CVAD-treated AYA patients from a single-center study, and comparable patient data from a retrospective study of pediatric regimen-treated AYA patients were utilized to estimate a relative progression difference (hazard ratio = 0.51) and model survival differences. Health-state utilities were estimated based on treatment stage, with an assumption that the pediatric protocol had 0.10 disutility compared with hyper-CVAD before the maintenance phase of treatment. Total life-years and quality-adjusted life-years (QALYs) were compared between treatment protocols at 1, 5, and 10 years, with additional probabilistic sensitivity analyses. Treatment with the pediatric-inspired protocol was associated with a 0.04 increase in life-years, but a 0.01 decrease in QALYs at 1 year. By years 5 and 10, the pediatric-inspired protocol resulted in 0.18 and 0.24 increase in life-years and 0.25 and 0.32 increase in QALYs, respectively, relative to hyper-CVAD. The lower quality of life associated with the induction and intensification phases of pediatric treatment was offset by more favorable progression-free survival and overall survival relative to hyper-CVAD. Our exploratory analysis suggests that, compared with hyper-CVAD, pediatric-inspired protocols may increase life-years throughout treatment stages and QALYs in the long term.
Beyond hydroxyurea: new and old drugs in the pipeline for sickle cell disease
2016-01-01
Despite Food and Drug Administration (FDA) approval of hydroxyurea to reduce the frequency of vaso-occlusive episodes, sickle cell disease (SCD) has continued to be treated primarily with analgesics for pain relief. However, elucidation of the multiple pathophysiologic mechanisms leading to vaso-occlusion and tissue injury in SCD has now resulted in a burgeoning effort to identify new treatment modalities to prevent or ameliorate the consequences of the disease. Development of new drugs as well as investigation of drugs previously used in other settings have targeted cell adhesion, inflammatory pathways, upregulation of hemoglobin F, hemoglobin polymerization and sickling, coagulation, and platelet activation. Although these efforts have not yet yielded drugs ready for FDA approval, several early studies have been extremely encouraging. Moreover, the marked increase in clinical pharmaceutical research addressing SCD and the new and old drugs in the pipeline make it reasonable to expect that we will soon have new treatments for SCD. PMID:26758919
Laser Photobiomodulation for a Complex Patient with Severe Hydroxyurea-Induced Oral Ulcerations.
Cabras, Marco; Cafaro, Adriana; Gambino, Alessio; Broccoletti, Roberto; Romagnoli, Ercole; Marina, Davide; Arduino, Paolo G
2016-01-01
Patients affected by polycythemia vera (PV), a myeloproliferative neoplasm characterized by an elevated red blood cell mass, are at high risk of vascular and thrombotic complications. Conventional therapeutic options aim at reducing vascular and thrombotic risk; low-dose aspirin and phlebotomy are first-line recommendations, for patients at low risk of thrombotic events, whereas cytoreductive therapy, usually hydroxyurea (HU) or interferon alpha, is recommended for high-risk patients. In the present study, we report the case of a patient with persistent oral ulcerations, possibly related to long-lasting HU treatment, firstly treated with topic and systemic corticosteroids and then more effectively with the addition of low-level laser therapy. Laser photobiomodulation has achieved pain control and has contributed to the healing of oral ulcers without any adverse effect; this has permitted a reduction in the dose of systemic corticosteroids and the suspension of the use of the topic ones, due to the long-term stability of oral health, even after the interruption of low-level laser therapy sessions.
Laser Photobiomodulation for a Complex Patient with Severe Hydroxyurea-Induced Oral Ulcerations
Cabras, Marco; Cafaro, Adriana; Broccoletti, Roberto; Romagnoli, Ercole; Marina, Davide
2016-01-01
Patients affected by polycythemia vera (PV), a myeloproliferative neoplasm characterized by an elevated red blood cell mass, are at high risk of vascular and thrombotic complications. Conventional therapeutic options aim at reducing vascular and thrombotic risk; low-dose aspirin and phlebotomy are first-line recommendations, for patients at low risk of thrombotic events, whereas cytoreductive therapy, usually hydroxyurea (HU) or interferon alpha, is recommended for high-risk patients. In the present study, we report the case of a patient with persistent oral ulcerations, possibly related to long-lasting HU treatment, firstly treated with topic and systemic corticosteroids and then more effectively with the addition of low-level laser therapy. Laser photobiomodulation has achieved pain control and has contributed to the healing of oral ulcers without any adverse effect; this has permitted a reduction in the dose of systemic corticosteroids and the suspension of the use of the topic ones, due to the long-term stability of oral health, even after the interruption of low-level laser therapy sessions. PMID:27957350
Feng, Wenyi; Collingwood, David; Boeck, Max E; Fox, Lindsay A; Alvino, Gina M; Fangman, Walton L; Raghuraman, Mosur K; Brewer, Bonita J
2006-02-01
During DNA replication one or both strands transiently become single stranded: first at the sites where initiation of DNA synthesis occurs (known as origins of replication) and subsequently on the lagging strands of replication forks as discontinuous Okazaki fragments are generated. We report a genome-wide analysis of single-stranded DNA (ssDNA) formation in the presence of hydroxyurea during DNA replication in wild-type and checkpoint-deficient rad53 Saccharomyces cerevisiae cells. In wild-type cells, ssDNA was first observed at a subset of replication origins and later 'migrated' bi-directionally, suggesting that ssDNA formation is associated with continuously moving replication forks. In rad53 cells, ssDNA was observed at virtually every known origin, but remained there over time, suggesting that replication forks stall. Telomeric regions seemed to be particularly sensitive to the loss of Rad53 checkpoint function. Replication origins in Schizosaccharomyces pombe were also mapped using our method.
Douglas, Genevieve; Harrison, Claire; Forsyth, Cecily; Bennett, Michael; Stevenson, William; Hounsell, John; Ratnasingam, Sumita; Ritchie, David; Ross, David M; Grigg, Andrew
2017-01-01
Hydroxyurea (Hu) is widely used as first-line cytoreductive therapy for patients with high-risk Philadelphia-negative myeloproliferative neoplasms (Ph-neg MPN), but a small proportion of patients have refractory disease or experience adverse effects. Studies have demonstrated busulfan (Bu) to be an active first-line agent, but data on its role as second-line or later therapy are minimal. To evaluate its efficacy and safety in this context, we undertook a multicenter audit of Ph-neg MPN patients who had received Bu as therapy for Hu intolerance or failure. Of 51 patients identified, 38 (75%) achieved either complete or partial hematological response following at least one Bu cycle. Bu was generally well tolerated, with only 21/135 (15%) cycles complicated by adverse effects, predominantly cytopenia; only 6% of cycles were ceased due to treatment complications. Bu is an effective and well-tolerated agent in patients with Ph-neg MPN in the setting of Hu intolerance or unresponsiveness.
Glazer, I.; Orion, D.
1984-01-01
Urea (U), hydroxyurea (HU), and thiourea (TU), in various concentrations, were added to chemically defined plant tissue culture medium on which Meloidogyne javanica was reared on excised tomato roots. Concentrations as low as 3 ppm HU or 12 ppm TU inhibited nematode maturation by 70-90% 4 weeks after inoculation, and the coenocytes in the parasitized tissue were poorly developed. Gall weight was also inhibited by 50% in cultures treated with 3 and 6 ppm HU. However, exposing juveniles of M. javanica and Tylenchulus semipenetrans or juveniles and adults of Pratylenchus thornei to increasing concentrations of HU or TU, up to 100 ppm, was not lethal. These two urea derivatives still inhibited nematode maturation when the infected region of the root was not in direct contact with the chemicals. Therefore, we suggest that these urea derivatives inhibit nematode development by affecting the plant metabolism essential to coenocyte formation, an occurrence similar to the hypersensitive reaction in a naturally resistant plant. PMID:19295888
Does Phase I Trial Enrollment Preclude Quality End of Life Care?
Levine, Deena R; Johnson, Liza-Marie; Mandrell, Belinda; Yang, Jie; West, Nancy; Hinds, Pamela S; Baker, Justin N
2015-01-01
BACKGROUND End-of-life care (EOLC) discussions and treatment-related decisions, including phase I trial enrollment, in patients with incurable disease are complex and can influence the quality of EOLC received. This study was conducted in pediatric oncology patients to determine if end-of-life characteristics differed between those who were and were not enrolled in a phase I trial. METHODS We reviewed medical records of 380 pediatric oncology patients (<22 years old at time of death) who died during a 3 ½ year period. 277 patients, with a diagnosis of a brain tumor or other solid tumor malignancy (n=103 hematologic malignancies excluded), were divided into two groups based on phase I trial enrollment; Phase I Cohort (PIC, n=120) and Non–Phase I Cohort (NPIC, n=157). EOLC characteristics of these two cohorts were compared by regression analysis and chi-square testing. RESULTS Comparison of patients in PIC and NPIC revealed no significant differences in a)demographics including: sex, race, religious affiliation, referral origin, diagnosis, or age at diagnosis, with the exception of age of death (P = 0.03) or in b)EOLC indices such as: utilization or timing of DNAR orders, hospice utilization or length of stay, forgoing life-sustaining therapies, location of death, time from first EOLC discussion to death and total number of EOLC discussions. CONCLUSION Our study of a large cohort of deceased pediatric cancer patients indicates that enrollment on a phase I trial does not affect EOLC characteristics, suggesting that quality EOLC can be delivered regardless of phase I trial participation. PMID:25557437
The Role of Salivary Neuropeptides in Pediatrics: Potential Biomarkers for Integrated Therapies.
Gershan, Lynn A; Durham, Paul L; Skidmore, Jaci; Shimizu, Joshua; Cady, Ryan J; Sheng, Xiaoming; Maloney, Christopher G
2015-08-01
Objective measures of symptom response to integrated complementary approaches in pediatrics are evolving. The purpose of this study was to document the concentration range of salivary neuropeptides in healthy controls and in children with cancer, to explore correlations between serum and salivary measurements for Calcitonin Gene-Related Peptide (CGRP) and Vasoactive Intestinal Polypeptide (VIP), and to determine whether there is a change in these salivary neuropeptide levels in response to integrated mind-body therapies. A non-randomized pragmatic study with three phases: Phase 1- Healthy Control Saliva-10 healthy controls provided saliva samples; Phase 2- Cancer Diagnosis Serum-Saliva- 16 mixed-type cancer patients provided blood and saliva samples; Phase 3- Acute Lymphocytic Leukemia (ALL) Saliva Intervention- 12 patients with ALL provided pre- and post-complementary intervention saliva samples. 20-minutes of structured touch or scripted relaxation breathing were administered to patients in Phase 3; Phase 1 and 2 patients did not receive this intervention. cortisol, CGRP, VIP, State/Trait Anxiety Scale, visual analogue scale, vital signs. Salivary CGRP and VIP were similar for children in Phases 1 and 2. There was a correlation between serum and salivary VIP in the mixed cancer group, though not between serum and salivary CGRP. In Phase 3 children, following a complementary intervention, salivary CGRP, heart rate, and systolic blood pressure decreased. These data provide evidence of a decrease in sympathetic output after integrative/complementary therapy intervention in children with cancer. The study underscores the potential role of salivary neuropeptides as non-invasive biomarkers for integrated therapies in pediatrics.
The Role of Salivary Neuropeptides in Pediatrics: Potential Biomarkers for Integrated Therapies
Gershan, Lynn A; Durham, Paul L; Skidmore, Jaci; Shimizu, Joshua; Cady, Ryan J; Sheng, Xiaoming; Maloney, Christopher G
2015-01-01
Introduction Objective measures of symptom response to integrated complementary approaches in pediatrics are evolving. The purpose of this study was to document the concentration range of salivary neuropeptides in healthy controls and in children with cancer, to explore correlations between serum and salivary measurements for Calcitonin Gene-Related Peptide (CGRP) and Vasoactive Intestinal Polypeptide (VIP), and to determine whether there is a change in these salivary neuropeptide levels in response to integrated mind-body therapies. Methods A non-randomized pragmatic study with three phases: Phase 1- Healthy Control Saliva-10 healthy controls provided saliva samples; Phase 2- Cancer Diagnosis Serum-Saliva- 16 mixed-type cancer patients provided blood and saliva samples; Phase 3- Acute Lymphocytic Leukemia (ALL) Saliva Intervention- 12 patients with ALL provided pre- and post-complementary intervention saliva samples. Interventions 20-minutes of structured touch or scripted relaxation breathing were administered to patients in Phase 3; Phase 1 and 2 patients did not receive this intervention. Outcome Measures cortisol, CGRP, VIP, State/Trait Anxiety Scale, visual analogue scale, vital signs. Results Salivary CGRP and VIP were similar for children in Phases 1 and 2. There was a correlation between serum and salivary VIP in the mixed cancer group, though not between serum and salivary CGRP. In Phase 3 children, following a complementary intervention, salivary CGRP, heart rate, and systolic blood pressure decreased. Discussion/Conclusions These data provide evidence of a decrease in sympathetic output after integrative/complementary therapy intervention in children with cancer. The study underscores the potential role of salivary neuropeptides as non-invasive biomarkers for integrated therapies in pediatrics. PMID:26388958
Bridging Adult Experience to Pediatrics in Oncology Drug Development.
Leong, Ruby; Zhao, Hong; Reaman, Gregory; Liu, Qi; Wang, Yaning; Stewart, Clinton F; Burckart, Gilbert
2017-10-01
Pediatric drug development in the United States has grown under the current regulations made permanent by the Food and Drug Administration Safety and Innovation Act of 2012. Over 1200 pediatric studies have now been submitted to the US FDA, but there is still a high rate of failure to obtain pediatric labeling for the indication pursued. Pediatric oncology represents special problems in that the disease is most often dissimilar to any cancer found in the adult population. Therefore, the development of drug dosing in pediatric oncology patients represents a special challenge. Potential approaches to pediatric dosing in oncology patients include extrapolation of efficacy from adult studies in those few cases where the disease is similar, inclusion of adolescent patients in adult trials when possible, and bridging the adult dose to the pediatric dose. An analysis of the recommended phase 2 dose for 40 molecularly targeted agents in pediatric patients provides some insight into current practices. Increased knowledge of tumor biology and efforts to identify and validate molecular targets and genetic abnormalities that drive childhood cancers can lead to increased opportunities for precision medicine in the treatment of pediatric cancers. © 2017, The American College of Clinical Pharmacology.
A developmental history of the Society of Pediatric Psychology.
White, S
1991-08-01
Presented history of the field of pediatric psychology in general and, more specifically, the development of the Society of Pediatric Psychology. Review began with 1896 concepts of Lightner Witmer and followed with 1960 activities by Logan Wright which led to the formation of the Society. The developmental phases of the Society are described with respect to goals, publications, financial status, training issues, and awards established. Present activities of liaisons with numerous outside organizations and agencies and regional conferences are detailed.
Sidhu, Manrita K; Goske, Marilyn J; Coley, Brian J; Connolly, Bairbre; Racadio, John; Yoshizumi, Terry T; Utley, Tara; Strauss, Keith J
2009-09-01
In the past several decades, advances in imaging and interventional techniques have been accompanied by an increase in medical radiation dose to the public. Radiation exposure is even more important in children, who are more sensitive to radiation and have a longer lifespan during which effects may manifest. To address radiation safety in pediatric computed tomography, in 2008 the Alliance for Radiation Safety in Pediatric Imaging launched an international social marketing campaign entitled Image Gently. This article describes the next phase of the Image Gently campaign, entitled Step Lightly, which focuses on radiation safety in pediatric interventional radiology.
Cellular biophysical markers of hydroxyurea treatment in sickle cell disease
NASA Astrophysics Data System (ADS)
So, Peter T. C.; Hosseini, Poorya; Abidi, Sabia Z.; Du, E.; Papageorgiou, Dimitrios P.; Park, YongKeun; Higgins, John; Kato, Gregory J.; Suresh, Subra; Dao, Ming; Yaqoob, Zahid
2017-04-01
Using a common-path interferometric technique, we measure biomechanical and morphological properties of individual red blood cells in SCD patients as a function of cell density, and investigate the correlation of these biophysical properties with drug intake as well as other clinically measured parameters.
NTP-CERHR Expert Panel Report on the reproductive and developmental toxicity of hydroxyurea
The National Toxicology Program (NTP) and the National Institute of Environmental Health Sciences (NIEHS) established the NTP Center for the Evaluation of Risks to Human Reproduction (CERHR) in June 1998. The purpose of CERHR is to provide timely, unbiased, scientifically sound e...
Levine, Deena R; Johnson, Liza-Marie; Mandrell, Belinda N; Yang, Jie; West, Nancy K; Hinds, Pamela S; Baker, Justin N
2015-05-01
End-of-life care (EOLC) discussions and treatment-related decisions, including phase 1 trial enrollment, in patients with incurable disease are complex and can influence the quality of EOLC received. The current study was conducted in pediatric oncology patients to determine whether end-of-life characteristics differed between those who were and were not enrolled in a phase 1 trial. The authors reviewed the medical records of 380 pediatric oncology patients (aged <22 years at the time of death) who died during a 3.5-year period. Of these, 103 patients with hematologic malignancies were excluded. A total of 277 patients with a diagnosis of a brain tumor or other solid tumor malignancy were divided into 2 groups based on phase 1 trial enrollment: a phase 1 cohort (PIC; 120 patients) and a non-phase 1 cohort (NPIC; 157 patients). The EOLC characteristics of these 2 cohorts were compared using regression analysis and chi-square testing. A comparison of patients in the PIC and NPIC revealed no significant differences in either demographic characteristics (including sex, race, religious affiliation, referral origin, diagnosis, or age at diagnosis, with the exception of age at the time of death [P =.03]) or in EOLC indices (such as use or timing of do not attempt resuscitation orders, hospice use or length of stay, forgoing life-sustaining therapies, location of death, time from first EOLC discussion to death, and total number of EOLC discussions). The results of the current study of a large cohort of deceased pediatric cancer patients indicate that enrollment on a phase 1 trial does not affect EOLC characteristics, suggesting that quality EOLC can be delivered regardless of phase 1 trial participation. © 2014 American Cancer Society.
Hankins, Jane S; Wynn, Lynn W; Brugnara, Carlo; Hillery, Cheryl A; Li, Chin-Shang; Wang, Winfred C
2008-01-01
In sickle cell anaemia, red cell dehydration increases intracellular HbS concentration and promotes sickling. Higher erythrocyte magnesium reduces water loss through negative regulation of membrane transporters. Hydroxycarbamide (also known as hydroxyurea) reduces sickling partly by increasing intracellular HbF. Combining drugs with distinct mechanisms could offer additive effects. A phase I trial combining oral magnesium pidolate and hydroxycarbamide was performed to estimate the maximum tolerated dose (MTD) and toxicity of magnesium. Cohorts of three children with HbSS, who were on a stable dose of hydroxycarbamide (median 28.5 mg/kg/d), received magnesium pidolate for 6 months beginning at 83 mg/kg/d. The dose was escalated by 50% for subsequent cohorts. Laboratory evaluations were performed at 0, 3, 6 and 9 months. Sixteen children (aged 4-12 years) participated. All four dose-limiting toxicities (grade III diarrhoea and abdominal pain) occurred within the first month of starting magnesium. Additionally, diarrhoea grades I (n = 1) and II (n = 3), and abdominal pain grade II (n = 3) occurred. Hydroxycarbamide dose reduction or interruption was not required. The MTD for magnesium pidolate used in combination with hydroxycarbamide was 125 mg/kg/d. KCl co-transporter activity declined after 3 months of magnesium pidolate (P = 0.02). A phase II study is needed to investigate the efficacy of this drug combination.
Cundy, Thomas P; Gattas, Nicholas E; White, Alan D; Najmaldin, Azad S
2015-08-01
The cumulative summation (CUSUM) method for learning curve analysis remains under-utilized in the surgical literature in general, and is described in only a small number of publications within the field of pediatric surgery. This study introduces the CUSUM analysis technique and applies it to evaluate the learning curve for pediatric robot-assisted laparoscopic pyeloplasty (RP). Clinical data were prospectively recorded for consecutive pediatric RP cases performed by a single-surgeon. CUSUM charts and tests were generated for set-up time, docking time, console time, operating time, total operating room time, and postoperative complications. Conversions and avoidable operating room delay were separately evaluated with respect to case experience. Comparisons between case experience and time-based outcomes were assessed using the Student's t-test and ANOVA for bi-phasic and multi-phasic learning curves respectively. Comparison between case experience and complication frequency was assessed using the Kruskal-Wallis test. A total of 90 RP cases were evaluated. The learning curve transitioned beyond the learning phase at cases 10, 15, 42, 57, and 58 for set-up time, docking time, console time, operating time, and total operating room time respectively. All comparisons of mean operating times between the learning phase and subsequent phases were statistically significant (P=<0.001-0.01). No significant difference was observed between case experience and frequency of post-operative complications (P=0.125), although the CUSUM chart demonstrated a directional change in slope for the last 12 cases in which there were high proportions of re-do cases and patients <6 months of age. The CUSUM method has a valuable role for learning curve evaluation and outcome quality monitoring. In applying this statistical technique to the largest reported single surgeon series of pediatric RP, we demonstrate numerous distinctly shaped learning curves and well-defined learning phase transition points. Copyright © 2015 Elsevier Inc. All rights reserved.
Spence, Nicholas D; Newton, Amanda S; Keaschuk, Rachel A; Ambler, Kathryn A; Jetha, Mary M; Holt, Nicholas L; Rosychuk, Rhonda J; Spence, John C; Sharma, Arya M; Ball, Geoff D C
Attrition in pediatric weight management is a substantial problem. This study examined factors associated with short- and long-term attrition from a lifestyle and behavioral intervention for parents of children with overweight or obesity. Fifty-two families with children ages 6 to 12 years old and body mass index at or above the 85th percentile participated in a randomized controlled trial focused on parents, comparing parent-based cognitive behavioral therapy with parent-based psychoeducation for pediatric weight management. We examined program attrition using two clinical phases of the intervention: short-term and long-term attrition, modeled using the general linear model. Predictors included intervention type, child/parent weight status, sociodemographic factors, and health of the family system. Higher self-assessed health of the family system was associated with lower short-term attrition; higher percentage of intervention sessions attended by parents was associated with lower long-term attrition. Different variables were significant in our short- and long-term models. Attrition might best be conceptualized based on short- and long-term phases of clinical, parent-based interventions for pediatric weight management. Copyright © 2016 National Association of Pediatric Nurse Practitioners. Published by Elsevier Inc. All rights reserved.
Kemmanu, Vasudha; Hegde, Kaushik; Giliyar, Subramanya K; Shetty, Bhujanga K; Kumaramanickavel, G; McCarty, Catherine A
2016-06-01
To determine the prevalence of childhood blindness and ocular morbidity in a rural pediatric population in South India. A population-based, cross-sectional survey of children was conducted in three phases in Pavagada and Madhugiri taluks (subdivisions) of Tumkur district in the state of Karnataka, India. In the first phase, trained fieldworkers screened 23,100 children. In the second phase, children with eye diseases were referred to the peripheral hospital to be examined by a general ophthalmologist. In the third phase, children with major eye diseases were examined by a pediatric ophthalmologist. The prevalence of ocular morbidity was 2.66% (95% confidence interval, CI, 2.46-2.87%). The most commonly observed ocular morbidity was Bitot spots (1%) followed by refractive error (0.6%). In total, 18 children were blind and the prevalence of childhood blindness (best-corrected visual acuity <3/60) was 0.08% (95% CI 0.04-0.11%); 8 (44.44%) had retinal blindness, 5 (27.76%) had lens-related blindness, 2 (11.11%) had bilateral microphthalmos, 1 (5.56%) was blind due to anterior staphyloma in the right eye and anophthalmos in the left eye, 1 (5.56%) had bilateral uveal coloboma and 1 (5.56%) had cortical visual impairment. Nearly half of the blindness in the population was due to unavoidable causes (retinal). In addition to providing eye care services, an appropriate service delivery model would include the provision of rehabilitative and low vision services and implementation of genetic studies to understand the causes and increase awareness of inherited eye diseases.
Scialpi, Michele; Schiavone, Raffaele; D'Andrea, Alfredo; Palumbo, Isabella; Magli, Michelle; Gravante, Sabrina; Falcone, Giuseppe; De Filippi, Claudio; Manganaro, Lucia; Palumbo, Barbara
2015-05-01
To evaluate the image quality and the diagnostic efficacy by single-phase whole-body 64-slice multidetector CT (MDCT) for pediatric oncology. Chest-abdomen-pelvis CT examinations with single-phase split-bolus technique were evaluated for T: detection and delineation of primary tumor (assessment of the extent of the lesion to neighboring tissues), N: regional lymph nodes and M: distant metastasis. Quality scores (5-point scale) were assessed by two radiologists on parenchymal and vascular enhancement. Accurate TNM staging in term of detection and delineation of primary tumor, regional lymph nodes and distant metastasis was obtained in all cases. On the image quality and severity artifact, the Kappa value for the interobserver agreement measure obtained from the analysis was 0.754, (p<0.001), characterizing a very good agreement between observers. Single-pass total body CT split-bolus technique reached the highest overall image quality and an accurate TNM staging in pediatric patients with cancer. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.
Factores relacionados con la elección de una especialidad en médicos residentes mexicanos.
Gutiérrez-Cirlos, Carlos; Naveja-Romero, José de Jesús; Leenen, Iwin; Sánchez-Mendiola, Melchor
2017-01-01
This study explored choice factors in four specialties in Mexico. Mixed methods design. Qualitative phase: four focus groups with first-year residents, to obtain information of how specialty choice was done. With this information a web-based cross-sectional questionnaire was applied to residents registered in the 1st year of Postgraduate Studies Division, UNAM. 32 residents participated in qualitative phase and for the quantitative phase, the survey was answered by 35 surgical, 28 gynecology, 61 internal medicine and 62 pediatric residents. The specialty choice decision was done during the last years of the medical career. The majority of the resident choice was a subspecialty after the general residency. The type of patient was more crucial to choose pediatrics while a good academic program was for internal medicine. Negative models and bullying were decisive to rule out surgery as well as a not well-known hospital was to rule out pediatrics. The specialty choice is done during undergraduate training, with the intention of doing a subspecialty. Demographic and personality traits were identified. Copyright: © 2017 SecretarÍa de Salud
Bruny, Jennifer L; Hall, Bruce L; Barnhart, Douglas C; Billmire, Deborah F; Dias, Mark S; Dillon, Peter W; Fisher, Charles; Heiss, Kurt F; Hennrikus, William L; Ko, Clifford Y; Moss, Lawrence; Oldham, Keith T; Richards, Karen E; Shah, Rahul; Vinocur, Charles D; Ziegler, Moritz M
2013-01-01
The American College of Surgeons (ACS) National Surgical Quality Improvement Program Pediatric (NSQIP-P) expanded to beta phase testing with the enrollment of 29 institutions. Data collection and analysis were aimed at program refinement and development of risk-adjusted models for inter-institutional comparisons. Data from the first full year of beta-phase NSQIP-P were analyzed. Patient accrual used ACS-NSQIP methodology tailored to pediatric specialties. Preliminary risk adjusted modeling for all pediatric and neonatal operations and pediatric (excluding neonatal) abdominal operations was performed for all cause morbidity (other than death) and surgical site infections (SSI) using hierarchical logistic regression methodology and eight predictor variables. Results were expressed as odds ratios with 95% confidence intervals. During calendar year 2010, 29 institutions enrolled 37,141 patients. 1644 total CPT codes were entered, of which 456 accounted for 90% of the cases. 450 codes were entered only once (1.2% of cases). For all cases, overall mortality was 0.25%, overall morbidity 7.9%, and the SSI rate 1.8%. For neonatal cases, mortality was 2.39%, morbidity 18.7%, and the SSI rate 3%. For the all operations model, risk-adjusted morbidity institutional odds ratios ranged 0.48-2.63, with 9/29 hospitals categorized as low outliers and 9/29 high outliers, while risk-adjusted SSI institutional odds ratios ranged 0.36-2.04, with 2/29 hospitals low outliers and 7/29 high outliers. This report represents the first risk-adjusted hospital-level comparison of surgical outcomes in infants and children using NSQIP-P data. Programmatic and analytic modifications will improve the impact of this program as it moves into full implementation. These results indicate that NSQIP-P has the potential to serve as a model for determining risk-adjusted outcomes in the neonatal and pediatric population with the goal of developing quality improvement initiatives for the surgical care of children. Copyright © 2013 Elsevier Inc. All rights reserved.
Interventions for preventing silent cerebral infarcts in people with sickle cell disease
Estcourt, Lise J; Fortin, Patricia M; Hopewell, Sally; Trivella, Marialena; Doree, Carolyn; Abboud, Miguel R
2017-01-01
This is the protocol for a review and there is no abstract. The objectives are as follows: To assess the effectiveness of red blood transfusions and hydroxyurea alone or in combination and HSCT to reduce or prevent SCI in people with SCD. PMID:28344510
Role of ABCB5 P-Glycoprotein in Breast Cancer Multidrug Resistance
2005-09-01
Hydroxyurea Doxorubicin Porfiromycin Mechlorethamine Fluorodopan Mitomycin Cytarabine (araC) Dianhydrogalactitol Gemcitabine Thiotepa N-N-Dibenzyl-daunomycin...0.0196 Mitomycin 0.4173 0.0318 Cytarabine (araC) 0.4163 0.0288 Dianhydrogalactitol 0.4105 0.0354 Gemcitabine 0.4088 0.0302 Thiotepa 0.4015 0.0232
New Business Models to Accelerate Innovation in Pediatric Oncology Therapeutics: A Review.
Das, Sonya; Rousseau, Raphaël; Adamson, Peter C; Lo, Andrew W
2018-06-02
Few patient populations are as helpless and in need of advocacy as children with cancer. Pharmaceutical companies have historically faced significant financial disincentives to pursue pediatric oncology therapeutics, including low incidence, high costs of conducting pediatric trials, and a lack of funding for early-stage research. Review of published studies of pediatric oncology research and the cost of drug development, as well as clinical trials of pediatric oncology therapeutics at ClinicalTrials.gov, identified 77 potential drug development projects to be included in a hypothetical portfolio. The returns of this portfolio were simulated so as to compute the financial returns and risk. Simulated business strategies include combining projects at different clinical phases of development, obtaining partial funding from philanthropic grants, and obtaining government guarantees to reduce risk. The purely private-sector portfolio exhibited expected returns ranging from -24.2% to 10.2%, depending on the model variables assumed. This finding suggests significant financial disincentives for pursuing pediatric oncology therapeutics and implies that financial support from the public and philanthropic sectors is essential. Phase diversification increases the likelihood of a successful drug and yielded expected returns of -5.3% to 50.1%. Standard philanthropic grants had a marginal association with expected returns, and government guarantees had a greater association by reducing downside exposure. An assessment of a proposed venture philanthropy fund demonstrated stronger performance than the purely private-sector-funded portfolio or those with traditional amounts of philanthropic support. A combination of financial and business strategies has the potential to maximize expected return while eliminating some downside risk-in certain cases enabling expected returns as high as 50.1%-that can overcome current financial disincentives and accelerate the development of pediatric oncology therapeutics.
Mahabee-Gittens, E Melinda; Dexheimer, Judith W; Khoury, Jane C; Miller, Julie A; Gordon, Judith S
2016-04-20
Tobacco smoke exposure (TSE) is unequivocally harmful to children's health, yet up to 48% of children who visit the pediatric emergency department (PED) and urgent care setting are exposed to tobacco smoke. The incorporation of clinical decision support systems (CDSS) into the electronic health records (EHR) of PED patients may improve the rates of screening and brief TSE intervention of caregivers and result in decreased TSE in children. We propose a study that will be the first to develop and evaluate the integration of a CDSS for Registered Nurses (RNs) into the EHR of pediatric patients to facilitate the identification of caregivers who smoke and the delivery of TSE interventions to caregivers in the urgent care setting. We will conduct a two-phase project to develop, refine, and integrate an evidence-based CDSS into the pediatric urgent care setting. RNs will provide input on program content, function, and design. In Phase I, we will develop a CDSS with prompts to: (1) ASK about child TSE and caregiver smoking, (2) use a software program, Research Electronic Data Capture (REDCap), to ADVISE caregivers to reduce their child's TSE via total smoking home and car bans and quitting smoking, and (3) ASSESS their interest in quitting and ASSIST caregivers to quit by directly connecting them to their choice of free cessation resources (eg, Quitline, SmokefreeTXT, or SmokefreeGOV) during the urgent care visit. We will create reports to provide feedback to RNs on their TSE counseling behaviors. In Phase II, we will conduct a 3-month feasibility trial to test the results of implementing our CDSS on changes in RNs' TSE-related behaviors, and child and caregiver outcomes. This trial is currently underway with funding support from the National Institutes of Health/National Cancer Institute. We have completed Phase I. The CDSS has been developed with input from our advisory panel and RNs, and pilot tested. We are nearing completion of Phase II, in which we are conducting the feasibility trial, analyzing data, and disseminating results. This project will develop, iteratively refine, integrate, and pilot test the use of an innovative CDSS to prompt RNs to provide TSE reduction and smoking cessation counseling to caregivers who smoke. If successful, this approach will create a sustainable and disseminable model for prompting pediatric practitioners to apply tobacco-related guideline recommendations. This systems-based approach has the potential to reach at least 12 million smokers a year and significantly reduce TSE-related pediatric illnesses and related costs.
Yacoub, A; Odenike, O; Verstovsek, S
2014-12-01
Considerable clinical experience regarding the long-term efficacy and safety of ruxolitinib has been gathered since the drug was approved in the USA for patients with intermediate or high-risk myelofibrosis (MF) in November 2011. Findings from the pivotal phase 3 COMFORT studies showed that ruxolitinib-associated reductions in MF-related splenomegaly and symptom burden occur rapidly and in the majority of patients. Two- and 3-year follow-up data further suggest that the benefits of ruxolitinib are durable and associated with a survival advantage compared with conventional therapies. However, careful management of treatment-related thrombocytopenia and anemia with dose modifications and supportive care is critical to allow chronic therapy. Based on preliminary evidence, ruxolitinib also allows spleen size and symptom reduction before allogeneic stem cell transplantation without negative effect on engraftment or outcomes. In recent studies, ruxolitinib provided effective management of hematologic parameters and symptoms in patients with polycythemia vera refractory to or intolerant of hydroxyurea.
Chk1 and Wee1 kinases coordinate DNA replication, chromosome condensation, and anaphase entry
Fasulo, Barbara; Koyama, Carol; Yu, Kristina R.; Homola, Ellen M.; Hsieh, Tao S.; Campbell, Shelagh D.; Sullivan, William
2012-01-01
Defects in DNA replication and chromosome condensation are common phenotypes in cancer cells. A link between replication and condensation has been established, but little is known about the role of checkpoints in monitoring chromosome condensation. We investigate this function by live analysis, using the rapid division cycles in the early Drosophila embryo. We find that S-phase and topoisomerase inhibitors delay both the initiation and the rate of chromosome condensation. These cell cycle delays are mediated by the cell cycle kinases chk1 and wee1. Inhibitors that cause severe defects in chromosome condensation and congression on the metaphase plate result in delayed anaphase entry. These delays are mediated by wee1 and are not the result of spindle assembly checkpoint activation. In addition, we provide the first detailed live analysis of the direct effect of widely used anticancer agents (aclarubicin, ICRF-193, VM26, doxorubicin, camptothecin, aphidicolin, hydroxyurea, cisplatin, mechlorethamine and x-rays) on key nuclear and cytoplasmic cell cycle events. PMID:22262459
Current and future treatment options for polycythemia vera.
Griesshammer, Martin; Gisslinger, Heinz; Mesa, Ruben
2015-06-01
Patients with polycythemia vera (PV), a myeloproliferative neoplasm characterized by an elevated red blood cell mass, are at high risk of vascular and thrombotic complications and have reduced quality of life due to a substantial symptom burden that includes pruritus, fatigue, constitutional symptoms, microvascular disturbances, and bleeding. Conventional therapeutic options aim at reducing vascular and thrombotic risk, with low-dose aspirin and phlebotomy as first-line recommendations for patients at low risk of thrombotic events and cytoreductive therapy (usually hydroxyurea or interferon alpha) recommended for high-risk patients. However, long-term effective and well-tolerated treatments are still lacking. The discovery of mutations in Janus kinase 2 (JAK2) as the underlying molecular basis of PV has led to the development of several targeted therapies, including JAK inhibitors, and results from the first phase 3 clinical trial with a JAK inhibitor in PV are now available. Here, we review the current treatment landscape in PV, as well as therapies currently in development.
Code of Federal Regulations, 2011 CFR
2011-04-01
... Phase 3 plan and protocols and the adequacy of current studies and plans to assess pediatric safety and...) “End-of-Phase 2” meetings and meetings held before submission of a marketing application. At specific... and evaluation process. In particular, FDA has found that meetings at the end of Phase 2 of an...
Zeng, Guohui; Teng, Yaoshu; Zhu, Jin; Zhu, Darong; Yang, Bin; Hu, Linping; Chen, Manman; Fu, Xiao
2018-01-01
The objective of the present study was to investigate the clinical application of magnetic resonance imaging (MRI)-respiratory gating technology for assessing illness severity in children with obstructive sleep apnea hypopnea syndrome (OSAHS).MRI-respiratory gating technology was used to scan the nasopharyngeal cavities of 51 children diagnosed with OSAHS during 6 respiratory phases. Correlations between the ratio of the area of the adenoid to the area of the nasopalatine pharyngeal cavity (Sa/Snp), with the main indexes of polysomnography (PSG), were analyzed. Receiver operator characteristic (ROC) curve and Kappa analysis were used to determine the diagnostic accuracy of Sa/Snp in pediatric OSAHS.The Sa/Snp was positively correlated with the apnea hypopnea index (AHI) (P < .001) and negatively correlated with the lowest oxygen saturation of blood during sleep (LaSO2) (P < .001). ROC analysis in the 6 respiratory phases showed that the area under the curve (AUC) of the Sa/Snp in the end-expiratory phase was the largest (0.992, P < .001), providing a threshold of 69.5% for the diagnosis of severe versus slight-moderate OSAHS in children. Consistency analysis with the AHI showed a diagnosis accordance rate of 96.0% in severe pediatric OSAHS and 96.2% in slight-moderate pediatric OSAHS (Kappa = 0.922, P < .001).Stenosis of the nasopalatine pharyngeal cavity in children with adenoidal hypertrophy was greatest at the end-expiration phase during sleep. The end-expiratory Sa/Snp obtained by a combination of MRI and respiratory gating technology has potential as an important imaging index for diagnosing and evaluating severity in pediatric OSAHS.
Transfusion Medicine in Sub-Saharan Africa: Conference Summary.
Dzik, Walter Sunny; Kyeyune, Dorothy; Otekat, Grace; Natukunda, Bernard; Hume, Heather; Kasirye, Phillip G; Ddungu, Henry; Kajja, Isaac; Dhabangi, Aggrey; Mugyenyi, Godfrey R; Seguin, Claire; Barnes, Linda; Delaney, Meghan
2015-07-01
In November 2014, a 3-day conference devoted to transfusion medicine in sub-Saharan Africa was held in Kampala, Uganda. Faculty from academic institutions in Uganda provided a broad overview of issues pertinent to transfusion medicine in Africa. The conference consisted of lectures, demonstrations, and discussions followed by 5 small group workshops held at the Uganda Blood Transfusion Service Laboratories, the Ugandan Cancer Institute, and the Mulago National Referral Hospital. Highlighted topics included the challenges posed by increasing clinical demands for blood, the need for better patient identification at the time of transfusion, inadequate application of the antiglobulin reagent during pretransfusion testing, concern regarding proper recognition and evaluation of transfusion reactions, the expanded role for nurse leadership as a means to improve patient outcomes, and the need for an epidemiologic map of blood usage in Africa. Specialty areas of focus included the potential for broader application of transcranial Doppler and hydroxyurea therapy in sickle cell disease, African-specific guidelines for transfusion support of cancer patients, the challenges of transfusion support in trauma, and the importance of African-centered clinical research in pediatric and obstetric transfusion medicine. The course concluded by summarizing the benefits derived from an organized quality program that extended from the donor to the recipient. As an educational tool, the slide-audio presentation of the lectures will be made freely available at the International Society of Blood Transfusion Academy Web site: http://www.isbtweb.org/academy/. Copyright © 2015 Elsevier Inc. All rights reserved.
Blood transfusion for preventing primary and secondary stroke in people with sickle cell disease.
Estcourt, Lise J; Fortin, Patricia M; Hopewell, Sally; Trivella, Marialena; Wang, Winfred C
2017-01-17
Sickle cell disease is one of the commonest severe monogenic disorders in the world, due to the inheritance of two abnormal haemoglobin (beta globin) genes. Sickle cell disease can cause severe pain, significant end-organ damage, pulmonary complications, and premature death. Stroke affects around 10% of children with sickle cell anaemia (HbSS). Chronic blood transfusions may reduce the risk of vaso-occlusion and stroke by diluting the proportion of sickled cells in the circulation.This is an update of a Cochrane Review first published in 2002, and last updated in 2013. To assess risks and benefits of chronic blood transfusion regimens in people with sickle cell disease for primary and secondary stroke prevention (excluding silent cerebral infarcts). We searched for relevant trials in the Cochrane Library, MEDLINE (from 1946), Embase (from 1974), the Transfusion Evidence Library (from 1980), and ongoing trial databases; all searches current to 04 April 2016.We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Trials Register: 25 April 2016. Randomised controlled trials comparing red blood cell transfusions as prophylaxis for stroke in people with sickle cell disease to alternative or standard treatment. There were no restrictions by outcomes examined, language or publication status. Two authors independently assessed trial eligibility and the risk of bias and extracted data. We included five trials (660 participants) published between 1998 and 2016. Four of these trials were terminated early. The vast majority of participants had the haemoglobin (Hb)SS form of sickle cell disease.Three trials compared regular red cell transfusions to standard care in primary prevention of stroke: two in children with no previous long-term transfusions; and one in children and adolescents on long-term transfusion.Two trials compared the drug hydroxyurea (hydroxycarbamide) and phlebotomy to long-term transfusions and iron chelation therapy: one in primary prevention (children); and one in secondary prevention (children and adolescents).The quality of the evidence was very low to moderate across different outcomes according to GRADE methodology. This was due to the trials being at a high risk of bias due to lack of blinding, indirectness and imprecise outcome estimates. Red cell transfusions versus standard care Children with no previous long-term transfusionsLong-term transfusions probably reduce the incidence of clinical stroke in children with a higher risk of stroke (abnormal transcranial doppler velocities or previous history of silent cerebral infarct), risk ratio 0.12 (95% confidence interval 0.03 to 0.49) (two trials, 326 participants), moderate quality evidence.Long-term transfusions may: reduce the incidence of other sickle cell disease-related complications (acute chest syndrome, risk ratio 0.24 (95% confidence interval 0.12 to 0.48)) (two trials, 326 participants); increase quality of life (difference estimate -0.54, 95% confidence interval -0.92 to -0.17) (one trial, 166 participants); but make little or no difference to IQ scores (least square mean: 1.7, standard error 95% confidence interval -1.1 to 4.4) (one trial, 166 participants), low quality evidence.We are very uncertain whether long-term transfusions: reduce the risk of transient ischaemic attacks, Peto odds ratio 0.13 (95% confidence interval 0.01 to 2.11) (two trials, 323 participants); have any effect on all-cause mortality, no deaths reported (two trials, 326 participants); or increase the risk of alloimmunisation, risk ratio 3.16 (95% confidence interval 0.18 to 57.17) (one trial, 121 participants), very low quality evidence. Children and adolescents with previous long-term transfusions (one trial, 79 participants)We are very uncertain whether continuing long-term transfusions reduces the incidence of: stroke, risk ratio 0.22 (95% confidence interval 0.01 to 4.35); or all-cause mortality, Peto odds ratio 8.00 (95% confidence interval 0.16 to 404.12), very low quality evidence.Several review outcomes were only reported in one trial arm (sickle cell disease-related complications, alloimmunisation, transient ischaemic attacks).The trial did not report neurological impairment, or quality of life. Hydroxyurea and phlebotomy versus red cell transfusions and chelationNeither trial reported on neurological impairment, alloimmunisation, or quality of life. Primary prevention, children (one trial, 121 participants)Switching to hydroxyurea and phlebotomy may have little or no effect on liver iron concentrations, mean difference -1.80 mg Fe/g dry-weight liver (95% confidence interval -5.16 to 1.56), low quality evidence.We are very uncertain whether switching to hydroxyurea and phlebotomy has any effect on: risk of stroke (no strokes); all-cause mortality (no deaths); transient ischaemic attacks, risk ratio 1.02 (95% confidence interval 0.21 to 4.84); or other sickle cell disease-related complications (acute chest syndrome, risk ratio 2.03 (95% confidence interval 0.39 to 10.69)), very low quality evidence. Secondary prevention, children and adolescents (one trial, 133 participants)Switching to hydroxyurea and phlebotomy may: increase the risk of sickle cell disease-related serious adverse events, risk ratio 3.10 (95% confidence interval 1.42 to 6.75); but have little or no effect on median liver iron concentrations (hydroxyurea, 17.3 mg Fe/g dry-weight liver (interquartile range 10.0 to 30.6)); transfusion 17.3 mg Fe/g dry-weight liver (interquartile range 8.8 to 30.7), low quality evidence.We are very uncertain whether switching to hydroxyurea and phlebotomy: increases the risk of stroke, risk ratio 14.78 (95% confidence interval 0.86 to 253.66); or has any effect on all-cause mortality, Peto odds ratio 0.98 (95% confidence interval 0.06 to 15.92); or transient ischaemic attacks, risk ratio 0.66 (95% confidence interval 0.25 to 1.74), very low quality evidence. There is no evidence for managing adults, or children who do not have HbSS sickle cell disease.In children who are at higher risk of stroke and have not had previous long-term transfusions, there is moderate quality evidence that long-term red cell transfusions reduce the risk of stroke, and low quality evidence they also reduce the risk of other sickle cell disease-related complications.In primary and secondary prevention of stroke there is low quality evidence that switching to hydroxyurea with phlebotomy has little or no effect on the liver iron concentration.In secondary prevention of stroke there is low-quality evidence that switching to hydroxyurea with phlebotomy increases the risk of sickle cell disease-related events.All other evidence in this review is of very low quality.
Blood transfusion for preventing primary and secondary stroke in people with sickle cell disease
Estcourt, Lise J; Fortin, Patricia M; Hopewell, Sally; Trivella, Marialena; Wang, Winfred C
2017-01-01
Background Sickle cell disease is one of the commonest severe monogenic disorders in the world, due to the inheritance of two abnormal haemoglobin (beta globin) genes. Sickle cell disease can cause severe pain, significant end-organ damage, pulmonary complications, and premature death. Stroke affects around 10% of children with sickle cell anaemia (HbSS). Chronic blood transfusions may reduce the risk of vaso-occlusion and stroke by diluting the proportion of sickled cells in the circulation. This is an update of a Cochrane Review first published in 2002, and last updated in 2013. Objectives To assess risks and benefits of chronic blood transfusion regimens in people with sickle cell disease for primary and secondary stroke prevention (excluding silent cerebral infarcts). Search methods We searched for relevant trials in the Cochrane Library, MEDLINE (from 1946), Embase (from 1974), the Transfusion Evidence Library (from 1980), and ongoing trial databases; all searches current to 04 April 2016. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Trials Register: 25 April 2016. Selection criteria Randomised controlled trials comparing red blood cell transfusions as prophylaxis for stroke in people with sickle cell disease to alternative or standard treatment. There were no restrictions by outcomes examined, language or publication status. Data collection and analysis Two authors independently assessed trial eligibility and the risk of bias and extracted data. Main results We included five trials (660 participants) published between 1998 and 2016. Four of these trials were terminated early. The vast majority of participants had the haemoglobin (Hb)SS form of sickle cell disease. Three trials compared regular red cell transfusions to standard care in primary prevention of stroke: two in children with no previous long-term transfusions; and one in children and adolescents on long-term transfusion. Two trials compared the drug hydroxyurea (hydroxycarbamide) and phlebotomy to long-term transfusions and iron chelation therapy: one in primary prevention (children); and one in secondary prevention (children and adolescents). The quality of the evidence was very low to moderate across different outcomes according to GRADE methodology. This was due to the trials being at a high risk of bias due to lack of blinding, indirectness and imprecise outcome estimates. Red cell transfusions versus standard care Children with no previous long-term transfusions Long-term transfusions probably reduce the incidence of clinical stroke in children with a higher risk of stroke (abnormal transcranial doppler velocities or previous history of silent cerebral infarct), risk ratio 0.12 (95% confidence interval 0.03 to 0.49) (two trials, 326 participants), moderate quality evidence. Long-term transfusions may: reduce the incidence of other sickle cell disease-related complications (acute chest syndrome, risk ratio 0.24 (95% confidence interval 0.12 to 0.48)) (two trials, 326 participants); increase quality of life (difference estimate -0.54, 95% confidence interval -0.92 to -0.17) (one trial, 166 participants); but make little or no difference to IQ scores (least square mean: 1.7, standard error 95% confidence interval -1.1 to 4.4) (one trial, 166 participants), low quality evidence. We are very uncertain whether long-term transfusions: reduce the risk of transient ischaemic attacks, Peto odds ratio 0.13 (95% confidence interval 0.01 to 2.11) (two trials, 323 participants); have any effect on all-cause mortality, no deaths reported (two trials, 326 participants); or increase the risk of alloimmunisation, risk ratio 3.16 (95% confidence interval 0.18 to 57.17) (one trial, 121 participants), very low quality evidence. Children and adolescents with previous long-term transfusions (one trial, 79 participants) We are very uncertain whether continuing long-term transfusions reduces the incidence of: stroke, risk ratio 0.22 (95% confidence interval 0.01 to 4.35); or all-cause mortality, Peto odds ratio 8.00 (95% confidence interval 0.16 to 404.12), very low quality evidence. Several review outcomes were only reported in one trial arm (sickle cell disease-related complications, alloimmunisation, transient ischaemic attacks). The trial did not report neurological impairment, or quality of life. Hydroxyurea and phlebotomy versus red cell transfusions and chelation Neither trial reported on neurological impairment, alloimmunisation, or quality of life. Primary prevention, children (one trial, 121 participants) Switching to hydroxyurea and phlebotomy may have little or no effect on liver iron concentrations, mean difference -1.80 mg Fe/g dry-weight liver (95% confidence interval -5.16 to 1.56), low quality evidence. We are very uncertain whether switching to hydroxyurea and phlebotomy has any effect on: risk of stroke (no strokes); all-cause mortality (no deaths); transient ischaemic attacks, risk ratio 1.02 (95% confidence interval 0.21 to 4.84); or other sickle cell disease-related complications (acute chest syndrome, risk ratio 2.03 (95% confidence interval 0.39 to 10.69)), very low quality evidence. Secondary prevention, children and adolescents (one trial, 133 participants) Switching to hydroxyurea and phlebotomy may: increase the risk of sickle cell disease-related serious adverse events, risk ratio 3.10 (95% confidence interval 1.42 to 6.75); but have little or no effect on median liver iron concentrations (hydroxyurea, 17.3 mg Fe/g dry-weight liver (interquartile range 10.0 to 30.6)); transfusion 17.3 mg Fe/g dry-weight liver (interquartile range 8.8 to 30.7), low quality evidence. We are very uncertain whether switching to hydroxyurea and phlebotomy: increases the risk of stroke, risk ratio 14.78 (95% confidence interval 0.86 to 253.66); or has any effect on all-cause mortality, Peto odds ratio 0.98 (95% confidence interval 0.06 to 15.92); or transient ischaemic attacks, risk ratio 0.66 (95% confidence interval 0.25 to 1.74), very low quality evidence. Authors’ conclusions There is no evidence for managing adults, or children who do not have HbSS sickle cell disease. In children who are at higher risk of stroke and have not had previous long-term transfusions, there is moderate quality evidence that long-term red cell transfusions reduce the risk of stroke, and low quality evidence they also reduce the risk of other sickle cell disease-related complications. In primary and secondary prevention of stroke there is low quality evidence that switching to hydroxyurea with phlebotomy has little or no effect on the liver iron concentration. In secondary prevention of stroke there is low-quality evidence that switching to hydroxyurea with phlebotomy increases the risk of sickle cell disease-related events. All other evidence in this review is of very low quality. PMID:24226646
Hydrogen Treatment Protects against Cell Death and Senescence Induced by Oxidative Damage.
Han, A Lum; Park, Seong-Hoon; Park, Mi Sung
2017-02-28
Hydrogen has potential for preventive and therapeutic applications as an antioxidant. However, micro- and macroparticles of hydrogen in water disappear easily over time. In order to eliminate reactive oxygen species (ROS) related with the aging process, we used functional water containing nanoparticle hydrogen. Nanoparticle hydrogen does not disappear easily and collapse under water after long periods of time. We used murine embryonic fibroblasts that were isolated from 12.5-day embryos of C57BL/6 mice. We investigated the ability of nanoparticle hydrogen in water to suppress hydroxyurea-induced ROS production, cytotoxicity, and the accumulation of β-galactosidase (an indicator of aging), and promote cell proliferation. The accumulation of β-galactosidase in the cytoplasm and the appearance of abnormal nuclei were inhibited by daily treatment of cells with hydrogen water. When the aging process was accelerated by hydroxyurea-induced oxidative stress, the effect of hydrogen water was even more remarkable. Thus, this study showed the antioxidant and anti-senescence effects of hydrogen water. Nanoparticle hydrogen water is potentially a potent anti-aging agent.
Pule, Gift D.; Mowla, Shaheen; Novitzky, Nicolas; Wiysonge, Charles S.; Wonkam, Ambroise
2016-01-01
Aims To report on molecular mechanisms of foetal haemoglobin (HbF) induction by hydroxyurea (HU) for the treatment of Sickle Cell Disease (SCD). Study Design Systematic review. Results Studies have provided consistent associations between genomic variations in HbF-promoting loci and variable HbF level in response to HU. Numerous signal transduction pathways have been implicated, through the identification of key genomic variants in BCL11A, HBS1L-MYB, SAR1 or XmnI polymorphism that predispose the response to the treatment, and signal transduction pathways, that modulate γ-globin expression (cAMP/cGMP; Giα/JNK/Jun; methylation and microRNA). Three main molecular pathways have been reported: 1) Epigenetic modifications, transcriptional events and signalling pathways involved in HU-mediated response, 2) Signalling pathways involving HU-mediated response and 3) Post-transcriptional pathways (regulation by microRNAs). Conclusions The complete picture of HU-mediated mechanisms of HbF production in SCD remains elusive. Research on post-transcriptional mechanisms could lead to therapeutic targets that may minimize alterations to the cellular transcriptome. PMID:26327494
Pule, Gift D; Mowla, Shaheen; Novitzky, Nicolas; Wiysonge, Charles S; Wonkam, Ambroise
2015-10-01
To report on molecular mechanisms of fetal hemoglobin (HbF) induction by hydroxyurea (HU) for the treatment of sickle cell disease. Systematic review. Studies have provided consistent associations between genomic variations in HbF-promoting loci and variable HbF level in response to HU. Numerous signal transduction pathways have been implicated, through the identification of key genomic variants in BCL11A, HBS1L-MYB, SAR1 or XmnI polymorphism that predispose the response to the treatment, and signal transduction pathways that modulate γ-globin expression (cAMP/cGMP; Giα/c-Jun N-terminal kinase/Jun; methylation and miRNA). Three main molecular pathways have been reported: i) Epigenetic modifications, transcriptional events and signaling pathways involved in HU-mediated response, ii) Signaling pathways involving HU-mediated response and iii) Post-transcriptional pathways (regulation by miRNAs). The complete picture of HU-mediated mechanisms of HbF production in Sickle Cell Disease remains elusive. Research on post-transcriptional mechanisms could lead to therapeutic targets that may minimize alterations to the cellular transcriptome.
Liu, Xiaodan; Liao, Wang; Peng, Hongxia; Luo, Xuequn; Luo, Ziyan; Jiang, Hua; Xu, Ling
2016-01-01
Abnormal expression of miRNAs is intimately related to a variety of human cancers. The purpose of this study is to confirm the expression of miR-181a and elucidate its physiological function and mechanism in pediatric acute myeloid leukemia (AML). Pediatric AML patients and healthy controls were enrolled, and the expression of miR-181a and ataxia telangiectasia mutated (ATM) in tissues were examined using quantitative PCR. Moreover, cell proliferation and cell cycle were evaluated in several cell lines (HL60, NB4 and K562) by using flow cytometry after transfected with miR-181a mimics and inhibitors, or ATM siRNA and control siRNA. Finally, ATM as the potential target protein of miR-181a was examined. We found that miR-181a was significantly increased in pediatric AML, which showed an inverse association with ATM expression. Overexpressed miR-181a in cell lines significantly enhanced cell proliferation, as well as increased the ratio of S-phase cells by miR-181a mimics transfection in vitro. Luciferase activity of the reporter construct identified ATM as the direct molecular target of miR-181a. ATM siRNA transfection significantly enhanced cell proliferation and increased the ratio of S-phase cells in vitro. The results revealed novel mechanism through which miR-181a regulates G1/S transition and cell proliferation in pediatric AML by regulating the tumor suppressor ATM, providing insights into the molecular mechanism in pediatric AML.
Validation of different pediatric triage systems in the emergency department
Aeimchanbanjong, Kanokwan; Pandee, Uthen
2017-01-01
BACKGROUND: Triage system in children seems to be more challenging compared to adults because of their different response to physiological and psychosocial stressors. This study aimed to determine the best triage system in the pediatric emergency department. METHODS: This was a prospective observational study. This study was divided into two phases. The first phase determined the inter-rater reliability of five triage systems: Manchester Triage System (MTS), Emergency Severity Index (ESI) version 4, Pediatric Canadian Triage and Acuity Scale (CTAS), Australasian Triage Scale (ATS), and Ramathibodi Triage System (RTS) by triage nurses and pediatric residents. In the second phase, to analyze the validity of each triage system, patients were categorized as two groups, i.e., high acuity patients (triage level 1, 2) and low acuity patients (triage level 3, 4, and 5). Then we compared the triage acuity with actual admission. RESULTS: In phase I, RTS illustrated almost perfect inter-rater reliability with kappa of 1.0 (P<0.01). ESI and CTAS illustrated good inter-rater reliability with kappa of 0.8–0.9 (P<0.01). Meanwhile, ATS and MTS illustrated moderate to good inter-rater reliability with kappa of 0.5–0.7 (P<0.01). In phase II, we included 1 041 participants with average age of 4.7±4.2 years, of which 55% were male and 45% were female. In addition 32% of the participants had underlying diseases, and 123 (11.8%) patients were admitted. We found that ESI illustrated the most appropriate predicting ability for admission with sensitivity of 52%, specificity of 81%, and AUC 0.78 (95%CI 0.74–0.81). CONCLUSION: RTS illustrated almost perfect inter-rater reliability. Meanwhile, ESI and CTAS illustrated good inter-rater reliability. Finally, ESI illustrated the appropriate validity for triage system. PMID:28680520
Nitric oxide-dependent killing of aerobic, anaerobic and persistent Burkholderia pseudomallei
Jones-Carson, Jessica; Laughlin, James R.; Stewart, Amanda L.; Voskuil, Martin I.; Vázquez-Torres, Andrés
2012-01-01
Burkholderia pseudomallei infections are fastidious to treat with conventional antibiotic therapy, often involving a combination of drugs and long-term regimes. Bacterial genetic determinants contribute to the resistance of B. pseudomallei to many classes of antibiotics. In addition, anaerobiosis and hypoxia in abscesses typical of melioidosis select for persistent populations of B. pseudomallei refractory to a broad spectrum of antibacterials. We tested the susceptibility of B. pseudomallei to the drugs hydroxyurea, spermine NONOate and DETA NONOate that release nitric oxide (NO). Our investigations indicate that B. pseudomallei are killed by NO in a concentration and time-dependent fashion. The cytoxicity of this diatomic radical against B. pseudomallei depends on both the culture medium and growth phase of the bacteria. Rapidly growing, but not stationary phase, B. pseudomallei are readily killed upon exposure to the NO donor spermine NONOate. NO also has excellent antimicrobial activity against anaerobic B. pseudomallei. In addition, persistent bacteria highly resistant to most conventional antibiotics are remarkably susceptible to NO. Sublethal concentrations of NO inhibited the enzymatic activity of [4Fe-4S]-cofactored aconitase of aerobic and anaerobic B. pseudomallei. The strong anti-B. pseudomallei activity of NO described herein merits further studies on the application of NO-based antibiotics for the treatment of melioidosis. PMID:22521523
Nitric oxide-dependent killing of aerobic, anaerobic and persistent Burkholderia pseudomallei.
Jones-Carson, Jessica; Laughlin, James R; Stewart, Amanda L; Voskuil, Martin I; Vázquez-Torres, Andrés
2012-06-30
Burkholderia pseudomallei infections are fastidious to treat with conventional antibiotic therapy, often involving a combination of drugs and long-term regimes. Bacterial genetic determinants contribute to the resistance of B. pseudomallei to many classes of antibiotics. In addition, anaerobiosis and hypoxia in abscesses typical of melioidosis select for persistent populations of B. pseudomallei refractory to a broad spectrum of antibacterials. We tested the susceptibility of B. pseudomallei to the drugs hydroxyurea, spermine NONOate and DETA NONOate that release nitric oxide (NO). Our investigations indicate that B. pseudomallei are killed by NO in a concentration and time-dependent fashion. The cytoxicity of this diatomic radical against B. pseudomallei depends on both the culture medium and growth phase of the bacteria. Rapidly growing, but not stationary phase, B. pseudomallei are readily killed upon exposure to the NO donor spermine NONOate. NO also has excellent antimicrobial activity against anaerobic B. pseudomallei. In addition, persistent bacteria highly resistant to most conventional antibiotics are remarkably susceptible to NO. Sublethal concentrations of NO inhibited the enzymatic activity of [4Fe-4S]-cofactored aconitase of aerobic and anaerobic B. pseudomallei. The strong anti-B. pseudomallei activity of NO described herein merits further studies on the application of NO-based antibiotics for the treatment of melioidosis. Copyright © 2012 Elsevier Inc. All rights reserved.
How I treat polycythemia vera.
Passamonti, Francesco
2012-07-12
Polycythemia vera (PV) is a clonal disorder characterized by unwarranted production of red blood cells. In the majority of cases, PV is driven by oncogenic mutations that constitutively activate the JAK-STAT signal transduction pathway, such as JAK2 V617F, or exon 12 mutations or LNK mutations. Diagnosis of PV is based on the WHO criteria. Diagnosis of post-PV myelofibrosis is established according to the International Working Group for Myeloproliferative Neoplasms Research and Treatment criteria. Different clinical presentations of PV are discussed. Prognostication of PV is tailored to the most frequent complication during follow-up, namely, thrombosis. Age older than 60 years and prior history of thrombosis are the 2 main risk factors for disease stratification. Correlations are emerging between leukocytosis, JAK2(V617F) mutation, BM fibrosis, and different outcomes of PV, which need to be confirmed in prospective studies. In my practice, hydroxyurea is still the "gold standard" when cytoreduction is needed, even though pegylated IFN-alfa-2a and ruxolitinib might be useful in particular settings. Results of phase 1 or 2 studies concerning these latter agents should however be confirmed by the ongoing randomized phase 3 clinical trials. In this paper, I discuss the main problems encountered in daily clinical practice with PV patients regarding diagnosis, prognostication, and therapy.
Hansen, Matthew; Meckler, Garth; Dickinson, Caitlyn; Dickenson, Kathryn; Jui, Jonathan; Lambert, William; Guise, Jeanne-Marie
2014-01-01
Objective Emergency Medical Services (EMS) providers may have critical knowledge gaps in pediatric care due to lack of exposure and training. There is currently little evidence to guide educators to the knowledge gaps most likely to improve patient safety. The objective of this study was to identify educational needs of EMS providers related to pediatric care in various domains in order to inform development of curricula. Methods The Children’s Safety Initiative-EMS performed a three-phase Delphi survey on patient safety in pediatric emergencies among providers and content experts in pediatric emergency care including physicians, nurses and pre-hospital providers of all levels. Each round included questions related to educational needs of providers or the effect of training on patient safety events. We identified knowledge gaps in the following domains: case exposure, competency and knowledge, assessment and decision making, and critical thinking and proficiency. Individual knowledge gaps were ranked by portion of respondents who ranked them “highly likely” (likert-type score 7–10 out of 10) to contribute to safety events. Results There were 737 respondents who were included in analysis of the first phase of the survey. Paramedics were 50.8% of respondents; EMT-Basics/first responders were 22% and physicians 11.4%. The top educational priorities identified in the final round of the survey include: pediatric airway management, responder anxiety when working with children, and general pediatric skills among providers. The top three needs in decision-making include knowing when to alter plans mid-course, knowing when to perform and advanced airway, and assessing pain in children. The top 3 technical or procedural skills needs were pediatric advanced airway, neonatal resuscitation, and intravenous/intraosseos access. For neonates, specific educational needs identified included knowing appropriate vital signs and preventing hypothermia. Conclusions This is the first large-scale Delphi survey related to pediatric pre-hospital education. Our results provide foundational information related to the educational needs of pre-hospital providers. Medical directors and educators can use the results to shape future curricular development. PMID:25296191
Hansen, Matthew; Meckler, Garth; Dickinson, Caitlyn; Dickenson, Kathryn; Jui, Jonathan; Lambert, William; Guise, Jeanne-Marie
2015-01-01
Emergency medical services (EMS) providers may have critical knowledge gaps in pediatric care due to lack of exposure and training. There is currently little evidence to guide educators to the knowledge gaps that most need to be addressed to improve patient safety. The objective of this study was to identify educational needs of EMS providers related to pediatric care in various domains in order to inform development of curricula. The Children's Safety Initiative-EMS performed a three-phase Delphi survey on patient safety in pediatric emergencies among providers and content experts in pediatric emergency care, including physicians, nurses, and prehospital providers of all levels. Each round included questions related to educational needs of providers or the effect of training on patient safety events. We identified knowledge gaps in the following domains: case exposure, competency and knowledge, assessment and decision making, and critical thinking and proficiency. Individual knowledge gaps were ranked by portion of respondents who ranked them "highly likely" (Likert-type score 7-10 out of 10) to contribute to safety events. There were 737 respondents who were included in analysis of the first phase of the survey. Paramedics were 50.8% of respondents, EMT-basics/first responders were 22%, and physicians 11.4%. The top educational priorities identified in the final round of the survey include pediatric airway management, responder anxiety when working with children, and general pediatric skills among providers. The top three needs in decision-making include knowing when to alter plans mid-course, knowing when to perform an advanced airway, and assessing pain in children. The top 3 technical or procedural skills needs were pediatric advanced airway, neonatal resuscitation, and intravenous/intraosseous access. For neonates, specific educational needs identified included knowing appropriate vital signs and preventing hypothermia. This is the first large-scale Delphi survey related to pediatric prehospital education. Our results provide foundational information related to the educational needs of prehospital providers. Medical directors and educators can use the results to shape future curricular development.
Smaldone, Arlene; Findley, Sally; Manwani, Deepa; Jia, Haomiao; Green, Nancy S
2018-06-01
To examine the effect of a community health worker (CHW) intervention, augmented by tailored text messages, on adherence to hydroxyurea therapy in youths with sickle cell disease, as well as on generic and disease-specific health-related quality of life (HrQL) and youth-parent self-management responsibility concordance. We conducted a 2-site randomized controlled feasibility study (Hydroxyurea Adherence for Personal Best in Sickle Cell Treatment [HABIT]) with 2:1 intervention allocation. Youths and parents participated as dyads. Intervention dyads received CHW visits and text message reminders. Data were analyzed using descriptive statistics, the Wilcoxon signed-rank test, and growth models adjusting for group assignment, time, and multiple comparisons. Changes in outcomes from 0 to 6 months were compared with their respective minimal clinically important differences. A total of 28 dyads (mean age of youths, 14.3 ± 2.6 years; 50% Hispanic) participated (18 in the intervention group, 10 in the control group), with 10.7% attrition. Accounting for group assignment, time, and multiple comparisons, at 6 months intervention youths reported improved generic HrQL total score (9.8 points; 95% CI, 0.4-19.2) and Emotions subscale score (15.0 points; 95% CI, 1.6-28.4); improved disease-specific subscale scores for Worry I (30.0 points; 95% CI, 8.5-51.5), Emotions (37.0 points, 95% CI, 9.4-64.5), and Communication I (17.8 points; 95% CI, 0.5-35.1); and 3-month dyad self-management responsibility concordance (3.5 points; 95% CI, -0.2 to 7.1). There were no differences in parent proxy-reported HrQL measures at 6 months. These findings add to research examining effects of behavioral interventions on HrQL outcomes in youths with sickle cell disease. ClinicalTrials.gov: NCT02029742. Copyright © 2018 Elsevier Inc. All rights reserved.
Where to Turn for Second-Line Cytoreduction After Hydroxyurea in Polycythemia Vera?
Nazha, Aziz; Gerds, Aaron T
2016-04-01
The goals of therapy in patients with polycythemia vera (PV) are to improve disease-related symptoms, prevent the incidence or recurrence of thrombosis, and possibly delay or prevent the transformation into myelofibrosis or acute myeloid leukemia (AML). Cytoreductive therapies have been used in older patients and those with a history of thrombosis to achieve these goals. Hydroxyurea (HU) remains the first-line cytoreductive choice; however, up to one in four patients treated with HU over time will develop resistance or intolerance to HU. More importantly, patients who fail HU have a 5.6-fold increase in mortality and a 6.8-fold increase risk of transformation to myelofibrosis or AML; therefore, alternative therapies are needed for these patients. Interferon-α has been used in PV and has shown significant activity in achieving hematologic responses and decreasing JAK2 V617F mutation allele burden. JAK inhibition has also been investigated and recently garnered regulatory approval for this indication. In this review, we will discuss the current treatment options that are available for patients after HU and the novel therapies that are currently under investigation. The outcomes of PV patients who fail or who are intolerant of hydroxyurea are poor. Although pegylated interferon can be considered in younger patients, currently, ruxolitinib is the only U.S. Food and Drug Administration-approved agent in this setting, representing a viable option, leading to hematocrit control and a reduction in spleen size and constitutional symptoms. Although a small number of patients will achieve a molecular response with continuous treatment, the implications of such response on the clinical outcomes are still unknown. Patients whose disease is not adequately controlled with ruxolitinib, or who lose their response, can be treated with low-dose busulfan or pipobroman; however, they should be encouraged to participate in trials with novel therapies. ©AlphaMed Press.
Gore, Lia; Kearns, Pamela R; de Martino, Maria Lucia; Lee; De Souza, Carmino Antonio; Bertrand, Yves; Hijiya, Nobuko; Stork, Linda C; Chung, Nack-Gyun; Cardos, Rocio Cardenas; Saikia, Tapan; Fagioli, Franca; Seo, Jong Jin; Landman-Parker, Judith; Lancaster, Donna; Place, Andrew E; Rabin, Karen R; Sacchi, Mariana; Swanink, Rene; Zwaan, C Michel
2018-05-01
Purpose Safe, effective treatments are needed for pediatric patients with chronic myeloid leukemia in chronic phase (CML-CP). Dasatinib is approved for treatment of adults and children with CML-CP. A phase I study determined suitable dosing for children with Philadelphia chromosome-positive (Ph+) leukemias. Methods CA180-226/NCT00777036 is a phase II, open-label, nonrandomized prospective trial of patients < 18 years of age receiving dasatinib. There are three cohorts: (1) imatinib-resistant/intolerant CML-CP, (2) imatinib-resistant/intolerant CML in accelerated/blast phase or Ph+ acute lymphoblastic leukemia (n = 17), and (3) newly diagnosed CML-CP treated with tablets or powder for oral suspension. Major cytogenetic response > 30% for imatinib-resistant/intolerant patients and complete cytogenetic response (CCyR) > 55% for newly diagnosed patients were of clinical interest. Results Of 113 patients with CML-CP, 14 (48%) who were imatinib-resistant/intolerant and 61 (73%) who were newly diagnosed remained on treatment at time of analysis. Major cytogenetic response > 30% was reached by 3 months in the imatinib-resistant/intolerant group and CCyR > 55% was reached by 6 months in the newly diagnosed CML-CP group. CCyR and major molecular response by 12 months, respectively, were 76% and 41% in the imatinib-resistant/intolerant group and 92% and 52% in newly diagnosed CML-CP group. Progression-free survival by 48 months was 78% and 93% in the imatinib-resistant/intolerant and newly diagnosed CML-CP groups, respectively. No dasatinib-related pleural or pericardial effusion, pulmonary edema, or pulmonary arterial hypertension were reported. Bone growth and development events were reported in 4% of patients. Conclusion In the largest prospective trial to date in children with CML-CP, we demonstrate that dasatinib is a safe, effective treatment of pediatric CML-CP. Target responses to first- or second-line dasatinib were met early, and deep molecular responses were observed. Safety of dasatinib in pediatric patients was similar to that observed in adults; however, no cases of pleural or pericardial effusion or pulmonary arterial hypertension were reported.
Manley, Peter E; Trippett, Tanya; Smith, Amy A; Macy, Margaret E; Leary, Sarah E S; Boklan, Jessica; Cohen, Kenneth J; Goldman, Stewart; Kilburn, Lindsay B; Dhall, Girish; Devin, Jeanne; Herzog, Cynthia E; Partap, Sonia; Fauchet, Floris; Badreddine, Emmy; Bernard, John P; Chi, Susan N
2018-05-11
This phase 1/2 study (NCT01751308) evaluated cabazitaxel in pediatric patients. Phase 1 determined the maximum tolerated dose (MTD) in patients with recurrent/refractory solid tumors, including central nervous system (CNS) tumors. Phase 2 evaluated activity in pediatric recurrent high-grade glioma (HGG) or diffuse intrinsic pontine glioma (DIPG). In phase 1, a 3 + 3 dose-escalation study design was followed. Cabazitaxel was administered at a starting dose of 20 mg/m 2 . Dose-limiting toxicities (DLTs) during cycle 1 were assessed to determine the MTD. Tumor response and cabazitaxel pharmacokinetics were also assessed. In phase 2, patients received cabazitaxel at the MTD determined in phase 1. Tumor responses were assessed every 9 weeks (modified Response Assessment in Neuro-oncology criteria). Progression-free survival and cabazitaxel pharmacokinetics were evaluated, and overall survival was estimated. In phase 1, 23 patients were treated, including 19 with CNS tumors. One patient had a partial response; five had stable disease for >3 cycles. Common adverse events included fatigue, diarrhea, nausea and vomiting, febrile neutropenia, and hypersensitivity reactions. Two of three DLTs (febrile neutropenia) occurred with a dose of 35 mg/m 2 ; the MTD was 30 mg/m 2 . Slightly higher cabazitaxel clearance was observed compared with adult trials. In phase 2, 16 patients (eight HGG and eight DIPG) were enrolled; 11 were evaluable for response and five withdrew (three due to anaphylaxis). All 11 patients progressed within four cycles. No responses were observed; the study was stopped due to futility. The safety profile of cabazitaxel was consistent with previous studies. The MTD (30 mg/m 2 ) was higher than the adult MTD. Cabazitaxel did not demonstrate activity in recurrent/refractory HGG or DIPG. © 2018 Wiley Periodicals, Inc.
Enhanced Cleaning and Education to Prevent Transmission of Clostridium difficile in Pediatrics
Aslam, Anoshé; Melendez, Giselle; Wang, Min; Stell, Frederic; Kelly, Paulette; Killinger, James; Dannaoui, Aimee; Riedman, Scott; Lopez, Ruben; Ackerman, Jill; Chou, Alexander; Wexler, Leonard; Smith, David; Sanchez, Stacy; Robilotti, Elizabeth; Kamboj, Mini; Eagan, Janet
2017-01-01
Abstract Background Transmission of healthcare-associated Clostridium difficile infection (HA-CDI) has been shown to occur directly or indirectly through a contaminated environment. At a tertiary-care cancer center, HA-CDI rates were higher for pediatric units than for other general oncology units. To address the problem, a multidisciplinary team, including Infection Control, Nursing, and Environmental Services (EVS), was convened and identified refusals and room clutter as barriers to proper cleaning of rooms on the unit. Aim: The aim of this study seeks to reduce HA-CDI in the inpatient pediatrics setting through environmental and educational interventions. Methods In the first phase of the study from February to April 2016, a baseline assessment of prevalent environmental disinfection practices was made among Nursing, EVS, Physicians, and Patient Representatives. Based on this feedback, the following were implemented during Phase 2, from June through October 2016: 1) Unit-wide disinfection with bleach twice a day including common and high traffic areas; 2) Initiation of a “preferred time for cleaning” program to engage families; 3) Enhanced visitor and family education on PPE use; 4) Creation of a communication plan in case of refusal to clean rooms; and 5) Dedicated use of diaper scales. Results During the first phase of the study, the following barriers to cleaning were identified: 1) High refusal rate as cleaning was perceived as inconvenient by families due to timing; 2) Common perception among EVS staff that multiple requests for cleaning the room may appear intrusive to the families; 3) Excessive clutter in the room; 4) Lack of education regarding PPE use; and 5) Shared equipment for diapers. To overcome these barriers, several interventions as outlined in methods were implemented. In Phase 2, there were 0 cases of HA-CDI identified in pediatric patients starting in July through October, 2016. Conclusion Control of CDI on pediatric units poses unique challenges. Engagement of key stakeholders is essential to identify and meet these challenges and to devise effective strategies that will ultimately lead to reduced hospital-based transmission of CDI. Disclosures All authors: No reported disclosures.
1988-12-01
day old tadpoles have completed most of organogenesis and, therefore, are usually not susceptible to malformation . An exception is limb development...antagonistic response may have b.een the result of poorer absorption of hydroxyurea by the severly malformed embryos, as isoniazid had a much greater...Short-chain carboxylic acids showed concentration additive joint actionsfor induction of malformation . Combinations of DNA synthesis inhibitors
Interventions for chronic kidney disease in people with sickle cell disease
Roy, Noemi BA; Fortin, Patricia M; Bull, Katherine R; Doree, Carolyn; Trivella, Marialena; Hopewell, Sally; Estcourt, Lise J
2017-01-01
This is the protocol for a review and there is no abstract. The objectives are as follows: To assess the effectiveness of any intervention in preventing or reducing kidney complications or CKD in people with SCD (including red blood cell transfusions, hydroxyurea and ACEI (either alone or in combination with each other)). PMID:28344511
Galal, Yasmine S; Labib, John R; Abouelhamd, Walaa A
2014-04-01
Healthcare-associated infection is a prominent problem among patients in pediatric intensive care units (PICU) as it could result in significant morbidity, prolonged hospitalization, and increase in medical care costs. The role of nurses is extremely important in preventing hazards and sequela of healthcare-associated infections. The aim of this study was to assess the effect of a health education program regarding infection-control measures on nurses' knowledge and attitude in PICUs at Cairo University hospitals. This was a pre-post test interventional study in which a convenient sample of 125 nurses was taken from the nursing staff in different PICUs at Cairo University hospitals. The study took place in three phases. In the first phase, the nursing staff's knowledge, attitude and practice concerning infection-control measures were tested using a self-administered pretested questionnaire and an observation checklist. The second phase included health education sessions in the form of powerpoint and video presentations; and in the third phase the nurses' knowledge and attitude on infection-control measures were reassessed. A significantly higher level of knowledge was revealed in the postintervention phase as compared with the preintervention phase with regards to the types of nosocomial infections (94.4 vs. 76.8%, P<0.001), the at-risk groups for acquiring infection (95.2 vs. 86.4%, P=0.035) and the measures applied to control nosocomial infections (89.6 vs. 68%, P<0.001). Nurses in the postintervention phase had significantly more knowledge about the types of hand washing (99.2 vs. 91.2%, P=0.006). A significantly higher percent of nurses in the postintervention phase knew the importance of avoiding recapping syringes (72.8 vs. 34.4%, P<0.001) and believed that infection-control measures could protect them completely from acquiring infection (79.2 vs. 65.6%, P=0.033). Statistically significant higher total knowledge and attitude scores were revealed in the postintervention phase as compared with the preintervention one (P<0.001). The percentage practice score of observed units was the highest among nurses in the neonatal intensive care unit at the Japanese Hospital (88%), whereas it was the lowest in the emergency pediatric unit (65%). There is scope for improvement in knowledge and attitude after educational program was offered to the nursing staff. Educational training programs should be multidisciplinary interventions in the era of quality control to help healthcare workers realize the importance of basic infection-control measures in reducing pediatric morbidity and mortality and improving the quality of care.
A case of non-Hodgkin lymphoma in a patient with chronic myeloid leukemia.
Găman, Amelia Maria; Dobrea, Camelia; Rotaru, Ionela
2013-01-01
Chronic myeloid leukemia is a clonal expansion of hematopoietic progenitor cells characterized by exaggerated proliferation of granulocytic lineage, with chronic phase, accelerated phase and blast crisis. Accelerated phase and blast crisis may be associated with extramedulary disease. Extramedullary transformation of CML can be determined both in nodal and extranodal sites. Non-Hodgkin lymphoma is rare in chronic myeloid leukemia and may be misdiagnosed as an extramedullary lymphoid blast transformation; the majorities are T-cell lymphomas with an immature thymic phenotype, while peripheral B-cell lymphomas are rarer. We report the case of a 79-year-old woman carrier Ph+ chronic myeloid leukemia who developed at eight months of diagnosis an accelerated phase of CML associated simultaneous with a tumor of soft palate, which was initial considering an extramedullary disease. The patient was treated with specific chemotherapy for accelerated phase of CML (Cytosinarabinoside) + Anagrelide, and reversed to secondary chronic phase of CML, but soft palate tumor persists. The immunohistochemical findings of bone marrow trephine biopsy examination showed chronic phase of CML (negativity for immature cells such as CD34, Tdt) and the biopsy of soft palate tumor and immunohistochemical findings revealed a primitive non-Hodgkin lymphoma (NHL) with medium B-cells (CD20, CD79a positive) and excluding an extramedullary blast crisis (CD34 negative, Tdt negative). Cytogenetic analysis in tumor revealed absence of Philadelphia chromosome. The patient was treated with local radiotherapy for NHL, with a favorable evolution and Hydroxyurea 1 g/day for CML with hematological remission. A localized lymphoid neoplasm may be an extramedullary localized blast crisis of CML or a distinct malignancy, with distinguished therapy and prognosis. A correct diagnosis based on a complex investigation: immunohistochemistry, conventional cytogenetic analysis and fluorescence in situ hybridization (FISH), molecular analysis (Southern blot and RT-PCR) is necessary. Further studies are required to clarify the pathogenetic relationship between chronic myeloid leukemia and non-Hodgkin lymphomas.
Characteristics of pediatric chemotherapy medication errors in a national error reporting database.
Rinke, Michael L; Shore, Andrew D; Morlock, Laura; Hicks, Rodney W; Miller, Marlene R
2007-07-01
Little is known regarding chemotherapy medication errors in pediatrics despite studies suggesting high rates of overall pediatric medication errors. In this study, the authors examined patterns in pediatric chemotherapy errors. The authors queried the United States Pharmacopeia MEDMARX database, a national, voluntary, Internet-accessible error reporting system, for all error reports from 1999 through 2004 that involved chemotherapy medications and patients aged <18 years. Of the 310 pediatric chemotherapy error reports, 85% reached the patient, and 15.6% required additional patient monitoring or therapeutic intervention. Forty-eight percent of errors originated in the administering phase of medication delivery, and 30% originated in the drug-dispensing phase. Of the 387 medications cited, 39.5% were antimetabolites, 14.0% were alkylating agents, 9.3% were anthracyclines, and 9.3% were topoisomerase inhibitors. The most commonly involved chemotherapeutic agents were methotrexate (15.3%), cytarabine (12.1%), and etoposide (8.3%). The most common error types were improper dose/quantity (22.9% of 327 cited error types), wrong time (22.6%), omission error (14.1%), and wrong administration technique/wrong route (12.2%). The most common error causes were performance deficit (41.3% of 547 cited error causes), equipment and medication delivery devices (12.4%), communication (8.8%), knowledge deficit (6.8%), and written order errors (5.5%). Four of the 5 most serious errors occurred at community hospitals. Pediatric chemotherapy errors often reached the patient, potentially were harmful, and differed in quality between outpatient and inpatient areas. This study indicated which chemotherapeutic agents most often were involved in errors and that administering errors were common. Investigation is needed regarding targeted medication administration safeguards for these high-risk medications. Copyright (c) 2007 American Cancer Society.
Singh, Amit; Rhee, Kyung E; Brennan, Jesse J; Kuelbs, Cynthia; El-Kareh, Robert; Fisher, Erin S
2016-03-01
Increase parent/caregiver ability to correctly identify the attending in charge and define terminology of treatment team members (TTMs). We hypothesized that correct TTM identification would increase with use of an electronic communication tool. Secondary aims included assessing subjects' satisfaction with and trust of TTM and interest in computer activities during hospitalization. Two similar groups of parents/legal guardians/primary caregivers of children admitted to the Pediatric Hospital Medicine teaching service with an unplanned first admission were surveyed before (Phase 1) and after (Phase 2) implementation of a novel electronic medical record (EMR)-based tool with names, photos, and definitions of TTMs. Physicians were also surveyed only during Phase 1. Surveys assessed TTM identification, satisfaction, trust, and computer use. More subjects in Phase 2 correctly identified attending physicians by name (71% vs. 28%, P < .001) and correctly defined terms intern, resident, and attending (P ≤ .03) compared with Phase 1. Almost all subjects (>79%) and TTMs (>87%) reported that subjects' ability to identify TTMs moderately or strongly impacted satisfaction and trust. The majority of subjects expressed interest in using computers to understand TTMs in each phase. Subjects' ability to correctly identify attending physicians and define TTMs was significantly greater for those who used our tool. In our study, subjects reported that TTM identification impacted aspects of the TTM relationship, yet few could correctly identify TTMs before tool use. This pilot study showed early success in engaging subjects with the EMR in the hospital and suggests that families would engage in computer-based activities in this setting. Copyright © 2016 by the American Academy of Pediatrics.
Gross, Oliver; Friede, Tim; Hilgers, Reinhard; Görlitz, Anke; Gavénis, Karsten; Ahmed, Raees; Dürr, Ulrike
2012-01-01
Introduction. Retrospective observational data show that ACE-inhibitor therapy delays renal failure and improves life expectancy in Alport patients with proteinuria. The EARLY PRO-TECT Alport trial assesses the safety and efficacy of early therapy onset with ramipril in pediatric Alport patients. Methods and analysis. This double-blind, randomized, placebo-controlled, multicenter phase III trial (NCT01485978; EudraCT-number 2010-024300-10) includes 120 pediatric patients aged 24 months to 18 years with early stages of Alport syndrome (isolated hematuria or microalbuminuria). From March 2012, up to 80 patients will be randomized 1:1 to ramipril or placebo. In the event of disease progression during 3-year treatment, patients are unblinded and ramipril is initiated, if applicable. Approximately 40 patients receive open-label ramipril contributing to the safety database. Primary end-points are "time to progression to next disease level" and "incidence of adverse drug events before disease progression." Treatment effect estimates from the randomized comparison and Alport registry data will be combined in supportive analyses to maximize evidence. Conclusion. Without this trial, ACE inhibitors may become standard off-label treatment in Alport syndrome without satisfactory evidence base. The results are expected to be of relevance for therapy of all pediatric patients with kidney disease, and the trial protocol might serve as a model for other rare pediatric glomerulopathies.
Cripe, Timothy P; Chen, Chun-Yu; Denton, Nicholas L; Haworth, Kellie B; Hutzen, Brian; Leddon, Jennifer L; Streby, Keri A; Wang, Pin-Yi; Markert, James M; Waters, Alicia M; Gillespie, George Yancey; Beierle, Elizabeth A; Friedman, Gregory K
2015-01-01
Progress for improving outcomes in pediatric patients with solid tumors remains slow. In addition, currently available therapies are fraught with numerous side effects, often causing significant life-long morbidity for long-term survivors. The use of viruses to kill tumor cells based on their increased vulnerability to infection is gaining traction, with several viruses moving through early and advanced phase clinical testing. The prospect of increased efficacy and decreased toxicity with these agents is thus attractive for pediatric cancer. In part I of this two-part review, we focus on strategies for utilizing oncolytic engineered herpes simplex virus (HSV) to target pediatric malignancies. We discuss mechanisms of action, routes of delivery, and the role of preexisting immunity on antitumor efficacy. Challenges to maximizing oncolytic HSV in children are examined, and we highlight how these may be overcome through various arming strategies. We review the preclinical and clinical evidence demonstrating safety of a variety of oncolytic HSVs. In Part II, we focus on the antitumor efficacy of oncolytic HSV in pediatric tumor types, pediatric clinical advances made to date, and future prospects for utilizing HSV in pediatric patients with solid tumors. PMID:26436135
Evidence-based interventions in pediatric psychology: progress over the decades.
Palermo, Tonya M
2014-09-01
This introduction to the special issue on Evidence-Based Interventions in Pediatric Psychology provides background on the process used to develop the special issue, a summary of the key findings from the series of reviews, and discussion of the implications for evidence-based practice. Authors followed a three-phase approach to develop their systematic reviews using rigorous systematic review methodology drawn heavily from the Cochrane Collaboration. The strength of the evidence for each pediatric psychology intervention was evaluated using Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. The introduction discusses the progress that has been made in the evidence base for pediatric psychology interventions since the first special series published in 1999. Recommendations to stimulate further research and expand and strengthen the quality of the evidence base are described. The introduction concludes with implications from the special issue for pediatric psychology training in evidence-based practice. © The Author 2014. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
The interaction of hydroxyurea and ionizing radiation in human cervical carcinoma cells.
Kuo, M L; Kunugi, K A; Lindstrom, M J; Kinsella, T J
1997-01-01
The results from prior in vitro and in vivo studies and recent phase 3 clinical trials suggest a significant potential role for hydroxyurea (HU) as a clinical radiosensitizer for cervix cancer. However, a detailed study of possible cellular mechanisms of radiosensitization in human cervix cancer cells as a consequence of dose and timing of HU and ionizing radiation (IR) has not been performed. This in vitro study analyses the interactions of HU and IR in a human cervical carcinoma cell line, Caski. Exponentially growing Caski cells were continuously exposed to clinically achievable but minimally cytotoxic concentrations of HU (0.3-3.0 mM) for various time intervals (6, 12, 18, 24, and 30 hours) up to one population doubling time either prior to or immediately following IR (2-8 Gy). The radiation survival data were analyzed using our modification of the linear-quadratic model to test for an interaction (greater than additive). The effects of HU alone, IR alone, and the combination on cell cycle progression and on apoptotic cell death in exponentially growing Caski cells were measured. We report a significant HU-IR interaction (radiosensitization) based on the sequence of HU exposure (post- > pre-IR) and with increasing concentrations of HU (0.3-3.0 mM), but no effect on radiosensitization with the duration of exposure to HU for up to one cell population doubling (6-30 hours). HU concentration has a significant effect on both alpha and beta linear-quadratic values in the post-IR sequences. Exposures of exponentially growing Caski cells to 1 mM and 3 mM HU alone result in a complete block in early S phase throughout the 30-hour exposure, while 0.3 mM HU causes a transient early S-phase block over the initial 12 to 18 hours of exposure. HU alone has no effect on cell cycle progression in G1 or G2/M populations but results in a large apoptotic population (31% following 1 mM HU x 30 hours), which appears to be the principal mechanism of drug cytotoxicity in these cells. IR alone (4 or 6 Gy) results in a significant G2 delay for 6 to 18 hours following IR but no G1 delay and a small apoptotic population at 30 hours post-IR (5.4% vs 2.1% in non-IR controls). The use of HU (0.3 or 1.0 mM) following IR (4 or 6 Gy) results in a significantly larger G2 delay compared with IR alone, but with only an additive effect on the apoptotic population. These in vitro data demonstrate that radiosensitization of Caski cells is more significant with post-IR exposures to clinically achievable concentrations of HU. This HU-IR interaction is associated with an increased G2 delay, suggesting a reduction in IR damage repair. However, this interaction appears to be independent of the cytotoxicity (principally by apoptosis) from HU alone.
Kol, Emine; Aydın, Perihan; Dursun, Oguz
2015-07-01
Noise is a substantial problem for both patients and healthcare workers in hospitals. This study aimed to determine the effectiveness of environmental strategies (creating single-patient rooms and reducing noise sources) in noise reduction in a pediatric intensive care unit. Noise measurement in the unit was conducted in two phases. In the first phase, measurements aimed at determining the unit's present level of noise were performed over 4 weeks in December 2013. During the month following the first measurement phase, the intensive care unit (ICU) was moved to a new location and noise-reducing strategies were implemented. The second phase, in May 2014, measured noise levels in the newly constructed environment. The noise levels before and after environmental changes were statistically significant at 72.6 dB-A and 56 dB-A, respectively (p < .05). Single-patient rooms and noise-reducing strategies can be effective in controlling environmental noise in the ICU. © 2015, Wiley Periodicals, Inc.
Blumfield, Einat; Zember, Jonathan; Guelfguat, Mark; Blumfield, Amit; Goldman, Harold
2015-12-01
We would like to share our experience of reducing pediatric radiation exposure. Much of the recent literature regarding successes of reducing radiation exposure has come from dedicated children's hospitals. Nonetheless, over the past two decades, there has been a considerable increase in CT imaging of children in the USA, predominantly in non-pediatric-focused facilities where the majority of children are treated. In our institution, two general hospitals with limited pediatric services, a dedicated initiative intended to reduce children's exposure to CT radiation was started by pediatric radiologists in 2005. The initiative addressed multiple issues including eliminating multiphase studies, decreasing inappropriate scans, educating referring providers, training residents and technologists, replacing CT with ultrasound or MRI, and ensuring availability of pediatric radiologists for consultation. During the study period, the total number of CT scans decreased by 24 %. When accounting for the number of scans per visit to the emergency department (ED), the numbers of abdominal and head CT scans decreased by 37.2 and 35.2 %, respectively. For abdominal scans, the average number of phases per scan decreased from 1.70 to 1.04. Upon surveying the pediatric ED staff, it was revealed that the most influential factors on ordering of scans were daily communication with pediatric radiologists, followed by journal articles and lectures by pediatric radiologists. We concluded that a non-pediatric-focused facility can achieve dramatic reduction in CT radiation exposure to children; however, this is most effectively achieved through a dedicated, multidisciplinary process led by pediatric radiologists.
Gill, Fenella J; Wilson, Sally; Aydon, Laurene; Leslie, Gavin D; Latour, Jos M
2017-11-01
To translate, culturally adapt, and psychometrically test the EMpowerment of PArents in The Intensive Care-30 questionnaire in Australian pediatric critical care, neonatal, and pediatric ward settings. Cross-sectional, descriptive, multicenter study conducted in two phases; 1) translation and cultural adaptation and 2) validation of the EMpowerment of PArents in The Intensive Care-30 questionnaire. Two Western Australian sites, the PICU and two pediatric wards of a children's hospital and the neonatal unit of a women's and newborn hospital. Parents whose baby or child was admitted to the participating wards or units with a length of hospital stay greater than 24 hours. None. Phase 1: A structured 10-step translation process adhered to international principles of good practice for translation and cultural adaptation of patient-reported outcomes. Thirty parents participated in cognitive debriefing. Phase 2: A total of 328 parents responded to the EMpowerment of PArents in The Intensive Care-30-AUS questionnaire. Reliability was sufficient (Cronbach α at domain level 0.70 -0.82, for each clinical area 0.56-0.86). Congruent validity was adequate between the domains and three general satisfaction items (rs 0.38-0.69). Nondifferential validity showed no significant effect size between three patient or parent demographic characteristics and the domains (Cohen's d < 0.36). Between the different clinical areas, significant differences in responses were found in all domains. The translated and culturally adapted EMpowerment of PArents in The Intensive Care-30-AUS is a reliable and valid questionnaire to measure parent-reported outcomes in pediatric critical care, pediatric ward, and neonatal hospital settings. Using this questionnaire can provide a framework for a standardized quality improvement approach and identification of best practices across specialties, hospital services and for benchmarking similar health services worldwide.
Iglesias, Alex; Iglesias, Adam
2014-01-01
A case of pediatric oppositional defiant disorder (ODD) with concomitant emotional dysregulation and secondary behavioral disruptiveness was treated with hypnosis by means of the hypnotic hold, a method adapted by the authors. An A-B-A-B time-series design with multiple replications was employed to measure the relationship of the hypnotic treatment to the dependent measure: episodes of emotional dysregulation with accompanying behavioral disruptiveness. The findings indicated a statistically significant relationship between the degree of change from phase to phase and the treatment. Follow-up at 6 months indicated a significant reduction of the frequency of targeted episodes of emotional dysregulation and behavioral disruptiveness at home.
Czajkowski, Susan M
2016-06-01
Pediatric obesity increases the risk of later-life obesity and chronic diseases. Basic research to better understand factors associated with excessive weight gain in early life and studies translating research findings into preventive and therapeutic strategies are essential to our ability to better prevent and treat childhood obesity. This overview describes several National Institutes of Health efforts designed to stimulate basic and translational research in childhood obesity prevention and treatment. These examples demonstrate the value of research in early phase translational pediatric obesity research and highlight some promising directions for this important area of research. Published by Elsevier Inc.
Ware, Russell E; Davis, Barry R; Schultz, William H; Brown, R Clark; Aygun, Banu; Sarnaik, Sharada; Odame, Isaac; Fuh, Beng; George, Alex; Owen, William; Luchtman-Jones, Lori; Rogers, Zora R; Hilliard, Lee; Gauger, Cynthia; Piccone, Connie; Lee, Margaret T; Kwiatkowski, Janet L; Jackson, Sherron; Miller, Scott T; Roberts, Carla; Heeney, Matthew M; Kalfa, Theodosia A; Nelson, Stephen; Imran, Hamayun; Nottage, Kerri; Alvarez, Ofelia; Rhodes, Melissa; Thompson, Alexis A; Rothman, Jennifer A; Helton, Kathleen J; Roberts, Donna; Coleman, Jamie; Bonner, Melanie J; Kutlar, Abdullah; Patel, Niren; Wood, John; Piller, Linda; Wei, Peng; Luden, Judy; Mortier, Nicole A; Stuber, Susan E; Luban, Naomi L C; Cohen, Alan R; Pressel, Sara; Adams, Robert J
2016-02-13
For children with sickle cell anaemia and high transcranial doppler (TCD) flow velocities, regular blood transfusions can effectively prevent primary stroke, but must be continued indefinitely. The efficacy of hydroxycarbamide (hydroxyurea) in this setting is unknown; we performed the TWiTCH trial to compare hydroxyurea with standard transfusions. TWiTCH was a multicentre, phase 3, randomised, open-label, non-inferiority trial done at 26 paediatric hospitals and health centres in the USA and Canada. We enrolled children with sickle cell anaemia who were aged 4-16 years and had abnormal TCD flow velocities (≥ 200 cm/s) but no severe vasculopathy. After screening, eligible participants were randomly assigned 1:1 to continue standard transfusions (standard group) or hydroxycarbamide (alternative group). Randomisation was done at a central site, stratified by site with a block size of four, and an adaptive randomisation scheme was used to balance the covariates of baseline age and TCD velocity. The study was open-label, but TCD examinations were read centrally by observers masked to treatment assignment and previous TCD results. Participants assigned to standard treatment continued to receive monthly transfusions to maintain 30% sickle haemoglobin or lower, while those assigned to the alternative treatment started oral hydroxycarbamide at 20 mg/kg per day, which was escalated to each participant's maximum tolerated dose. The treatment period lasted 24 months from randomisation. The primary study endpoint was the 24 month TCD velocity calculated from a general linear mixed model, with the non-inferiority margin set at 15 cm/s. The primary analysis was done in the intention-to-treat population and safety was assessed in all patients who received at least one dose of assigned treatment. This study is registered with ClinicalTrials.gov, number NCT01425307. Between Sept 20, 2011, and April 17, 2013, 159 patients consented and enrolled in TWiTCH. 121 participants passed screening and were then randomly assigned to treatment (61 to transfusions and 60 to hydroxycarbamide). At the first scheduled interim analysis, non-inferiority was shown and the sponsor terminated the study. Final model-based TCD velocities were 143 cm/s (95% CI 140-146) in children who received standard transfusions and 138 cm/s (135-142) in those who received hydroxycarbamide, with a difference of 4·54 (0·10-8·98). Non-inferiority (p=8·82 × 10(-16)) and post-hoc superiority (p=0·023) were met. Of 29 new neurological events adjudicated centrally by masked reviewers, no strokes were identified, but three transient ischaemic attacks occurred in each group. Magnetic resonance brain imaging and angiography (MRI and MRA) at exit showed no new cerebral infarcts in either treatment group, but worsened vasculopathy in one participant who received standard transfusions. 23 severe adverse events in nine (15%) patients were reported for hydroxycarbamide and ten serious adverse events in six (10%) patients were reported for standard transfusions. The most common serious adverse event in both groups was vaso-occlusive pain (11 events in five [8%] patients with hydroxycarbamide and three events in one [2%] patient for transfusions). For high-risk children with sickle cell anaemia and abnormal TCD velocities who have received at least 1 year of transfusions, and have no MRA-defined severe vasculopathy, hydroxycarbamide treatment can substitute for chronic transfusions to maintain TCD velocities and help to prevent primary stroke. National Heart, Lung, and Blood Institute, National Institutes of Health. Copyright © 2016 Elsevier Ltd. All rights reserved.
Stepney, Cesalie; Kane, Katelyn; Bruzzese, Jean-Marie
2011-10-01
Pediatric asthma is often undiagnosed, and therefore untreated. It negatively impacts children's functioning, including school attendance and performance, as well as quality of life. Schoolwide screening for asthma is becoming increasingly common, making identification of possible asthma particularly relevant for school nurses. Nurses may need to help parents cope with the new diagnosis, and teach them skills to manage the illness. The aim of this article is to present a three-phase model of how parents cope with a newly diagnosed pediatric chronic illness. Using asthma as an example, we describe these phases (Emotional Crisis, Facing Reality, and Reclaiming Life), illustrate how parents progress through the phases, and discuss situations associated with possible regression. Next, we offer strategies framed around a theory of asthma self-management to assist school nurses and other medical providers to motivate parents to develop successful disease management skills.
Joint Actions of Developmental Toxicants.
1991-06-01
antagonistic response may have been the result of poorer absorption of hydroxyurea by the severly malformed embryos, as isoniazid had a much greater...chain carboxylic acids showed concentration additive joint actions for induction of malformation . Combinations of DNA synthesis inhibitors showed...response additive to antagonistic joint actions at malformation -inducing con- centrations. Since each compound inhibits a different enzyme in the process of
Fetal hemoglobin in sickle cell anemia: The Arab-Indian haplotype and new therapeutic agents.
Habara, Alawi H; Shaikho, Elmutaz M; Steinberg, Martin H
2017-11-01
Fetal hemoglobin (HbF) has well-known tempering effects on the symptoms of sickle cell disease and its levels vary among patients with different haplotypes of the sickle hemoglobin gene. Compared with sickle cell anemia haplotypes found in patients of African descent, HbF levels in Saudi and Indian patients with the Arab-Indian (AI) haplotype exceed that in any other haplotype by nearly twofold. Genetic association studies have identified some loci associated with high HbF in the AI haplotype but these observations require functional confirmation. Saudi patients with the Benin haplotype have HbF levels almost twice as high as African patients with this haplotype but this difference is unexplained. Hydroxyurea is still the only FDA approved drug for HbF induction in sickle cell disease. While most patients treated with hydroxyurea have an increase in HbF and some clinical improvement, 10 to 20% of adults show little response to this agent. We review the genetic basis of HbF regulation focusing on sickle cell anemia in Saudi Arabia and discuss new drugs that can induce increased levels of HbF. © 2017 Wiley Periodicals, Inc.
Fertility challenges for women with sickle cell disease.
Ghafuri, Djamila L; Stimpson, Sarah-Jo; Day, Melissa E; James, Andra; DeBaun, Michael R; Sharma, Deva
2017-10-01
Sickle cell disease (SCD) represents one of the most common monogenic blood disorders worldwide, with an incidence of over 300,000 newborns affected per year. Reproductive challenges for men and women with SCD have been previously reviewed; however, evidence-based strategies to prevent and manage infertility and increase fecundity are lacking in women with SCD, which is one of the most important factors for quality of life. Areas covered: This review article summarizes the known risk factors for infertility, low fecundity, and premature menopause related to SCD. Expert commentary: Women with SCD have unique risk factors that may impact their ability to conceive, including chronic inflammation, oxidative stress, transfusion-related hemochromatosis, and ovarian sickling, causing ischemia and reperfusion injury to the ovary. Contraception is strongly recommended while on hydroxyurea therapy during reproductive years and discontinuing hydroxyurea for family planning and during pregnancy based on teratogenicity in animal studies. Hematopoietic stem cell transplantation (HSCT), the only curative therapy, sometimes involves conditioning regimens containing alkylating agents and total body irradiation that contribute to infertility and premature ovarian failure. Prior to HSCT or gene therapy, we strongly recommend referral to a reproductive endocrinologist to discuss fertility preservation and surrogacy options for all women with SCD.
Prasugrel hydrochloride for the treatment of sickle cell disease.
Conran, Nicola; Rees, David C
2017-07-01
Therapeutic options for sickle cell disease (SCD) are limited and, currently, only one drug (hydroxyurea) has FDA approval for the treatment of adult SCD. While this genetic disease is caused by hemoglobin polymerization, subsequent downstream events trigger platelet activation, vaso-occlusion and the disease's complex pathophysiology. Areas covered: The oral thienopyridine, prasugrel hydrochloride, irreversibly inhibits the P2Y12 receptors, inhibiting ADP-dependent platelet activation. We discuss recent clinical trials evaluating the pharmokinetics of prasugrel and its potential for use in SCD. Expert opinion: Prasugrel administration in SCD appears to be well tolerated and safe. However, although this drug modestly inhibits platelet activity in these patients, administration of prasugrel to a large group of children and adolescents for up to 24 months failed to convincingly reduce vaso-occlusive complications. Speculatively, prasugrel may be of occasional use for off-license purposes in patients unable or unwilling to take hydroxyurea (particularly in 12-17-year olds). Although there is currently no prospect of prasugrel being licensed for use in SCD, the success of on-going trials of other antiplatelet agents in SCD might lead to further trials of prasugrel in SCD.
Splanchnic vein thrombosis in myeloproliferative neoplasms: treatment algorithm 2018.
Finazzi, Guido; De Stefano, Valerio; Barbui, Tiziano
2018-06-26
Myeloproliferative neoplasms (MPNs) are a leading cause of splanchnic vein thrombosis (SVT). SVT is observed in all MPNs and frequently affects young patients. Therapy should be addressed to three main goals: preventing thrombosis recurrence, managing the underlying MPN, and supporting liver dysfunction. Life-long oral anticoagulation with vitamin K antagonists is the cornerstone of the antithrombotic treatment. However, recurrences of SVT or other thrombosis may occur in 15-20% of patients. Direct oral anticoagulants can represent an alternative and preliminary data encourage comparative studies. Survival of patients with SVT in MPN is primarily influenced by the natural history of the underlying neoplasms, rather than the SVT event. An aggressive management is recommended and a treatment algorithm based on the different MPN subtypes is proposed. Hydroxyurea is the cytoreductive drug of choice in polycythemia vera and essential thrombocythemia, whereas ruxolitinib is indicated in intermediate and high-risk patients with myelofibrosis and in PV patients resistant or intolerant to hydroxyurea. The management of SVT in MPNs requires a multidisciplinary approach that may include a hematologist, a gastroenterologist, an interventional radiologist, and a surgeon. In the case of clinical deterioration despite pharmacological therapy, patients with SVT should be considered for invasive procedures or liver transplantation.
Lassmann, G; Curtis, J; Liermann, B; Mason, R P; Eling, T E
1993-01-01
Using ESR spectroscopy, the ability of enzyme inhibitors to quench protein-derived tyrosyl radicals was studied in two different enzymes, prostaglandin H synthase and ribonucleotide reductase. The prostaglandin H synthase inhibitors indomethacin, eugenol, and MK-410 effectively prevent the formation of tyrosyl radicals during the oxidation of arachidonic acid by prostaglandin H synthase from ram seminal vesicles. A direct reaction with preformed tyrosyl radicals was observed only with eugenol. The other prostaglandin H synthase inhibitors were ineffective. The ribonucleotide reductase inhibitors hydroxyurea and 4-hydroxyanisole, which effectively inactivate the tyrosyl radical in the active site of ribonucleotide reductase present in tumor cells, exhibit a different reactivity with tyrosyl radicals formed by prostaglandin H synthase. Hydroxyurea quenches preformed tyrosyl radicals in prostaglandin H synthase weakly, whereas 4-hydroxyanisole does not quench tyrosyl radicals in prostaglandin H synthase at all. Eugenol, which quenches preformed prostaglandin H synthase-derived tyrosyl radicals, also quenches the tyrosyl radical in ribonucleotide reductase. The results suggest that the reactivity of protein-linked tyrosyl radicals in ribonucleotide reductase and those formed during prostaglandin H synthase catalysis are very different and have unrelated roles in enzyme catalysis.
Inpatient management of sickle cell pain: a 'snapshot' of current practice.
Miller, Scott T; Kim, Hae-Young; Weiner, Debra; Wager, Carrie G; Gallagher, Dianne; Styles, Lori; Dampier, Carlton D
2012-03-01
The Sickle Cell Disease Clinical Research Network (SCDCRN) designed the PROACTIVE Feasibility Study (ClinicalTrials.gov NCT00951808) to determine whether elevated serum levels of secretory phospholipase A2 (sPLA2) during hospitalization for pain would permit preemptive therapy of sickle cell acute chest syndrome (ACS) by blood transfusion. While PROACTIVE was not designed to assess pain management and was terminated early due to inadequate patient accrual, collection of clinical data allowed a "snapshot" of current care by expert providers. Nearly half the patients admitted for pain were taking hydroxyurea; hydroxyurea did not affect length of stay. Providers commonly administered parenteral opioid analgesia, usually morphine or hydromorphone, to adults and children, generally by patient-controlled analgesia (PCA). Adult providers were more likely to prescribe hydromorphone and did so at substantially higher morphine equivalent doses than were given to adults receiving morphine; the latter received doses similar to children who received either medication. All subjects treated with PCA received higher daily doses of opioids than those treated by time-contingent dosing. Physicians often restricted intravenous fluids to less than a maintenance rate and underutilized incentive spirometry, which reduces ACS in patients hospitalized for pain.
Inpatient Management of Sickle Cell Pain: a Snapshot of Current Practice
Miller, Scott T.; Kim, Hae-Young; Weiner, Debra; Wager, Carrie G.; Gallagher, Dianne; Styles, Lori; Dampier, Carlton D.
2012-01-01
The Sickle Cell Disease Clinical Research Network (SCDCRN) designed the PROACTIVE Feasibility Study (ClinicalTrials.gov NCT00951808) to determine whether elevated serum levels of secretory phospholipase A2 (sPLA2) during hospitalization for pain would permit preemptive therapy of sickle cell acute chest syndrome (ACS) by blood transfusion. [1, 2] While PROACTIVE was not designed to assess pain management and terminated early due to inadequate patient accrual, collection of clinical data allowed a “snapshot” of current care by expert providers. Nearly half the patients admitted for pain were taking hydroxyurea; hydroxyurea did not affect length of stay. Providers commonly administered parenteral opioid analgesia, usually morphine or hydromorphone, to adults and children, generally by patient-controlled analgesia (PCA). Adult providers were more likely to prescribe hydromorphone and did so at substantially higher morphine equivalent doses than were given to adults receiving morphine; the latter received doses similar to children who received either medication. All subjects treated with PCA received higher daily doses of opioids than those treated by time-contingent dosing. Physicians often restricted intravenous fluids to less than a maintenance rate and underutilized incentive spirometry, which reduces ACS in patients hospitalized for pain. [3] PMID:22231150
Ribonucleotide Reductase Inhibitors Reduce Atherosclerosis in a Double-Injury Rabbit Model
Gallaugher, Laura D; Henry, Jon C; Kearns, Patrick N; Elford, Howard L; Bergdall, Valerie K; Cardounel, Arturo J
2009-01-01
Atheroproliferative disorders such as atherosclerosis are an important health problem and one of the leading causes of morbidity and mortality in the United States. Minimally invasive therapeutic procedures, including angioplasty with stent deployment, are used frequently for obstructive coronary artery disease. However, restenosis, a proliferative vascular response, is a common sequela to this procedure. The current study investigated the effect of inhibiting ribonucleotide reductase (RR), an enzyme necessary for cellular proliferation, in an attempt to ameliorate the proliferative response. Two RR inhibitors, didox and hydroxyurea, were chosen for their potent antiproliferative properties. Studies were carried out by using a double-injury rabbit model, in which endothelial denudation was followed by the administration of a high-fat diet. At 4 wk after initial endothelial denudation, the developing atherosclerotic lesion was subjected to transluminal balloon dilation to simulate clinical intervention with percutaneous transluminal angioplasty. The degree of restenosis and atheroproliferation was assessed at 8 wk. Histologic evaluation of the lesion demonstrated that treatment with didox and hydroxyurea significantly decreased lesion area and lumen loss. These results suggest that RR inhibition may be an effective new tool for the treatment of atheroproliferative disorders. PMID:20034432
An exceptional case of renal artery restenosis in a patient with polycythaemia vera.
Gavriilaki, Eleni; Sampanis, Nikolaos; Kavlakoudis, Christos; Papaioannou, George; Vasileiou, Sotirios
2014-12-01
Polycythaemia vera represents a rare chronic myeloproliferative neoplasm characterized by an increased thrombotic risk. Previous case reports have documented a link between primary or secondary polycythemia and the presence of renal artery stenosis and renovascular hypertension. Herein, we report an exceptional case of renal artery restenosis leading to uncontrolled hypertension in a patient with PV and high haematocrit levels. A 52-year-old female patient with a history of polycythaemia vera under treatment with hydroxyurea and phlebotomy presented in our outpatient clinic with newly diagnosed hypertension caused by left renal artery stenosis. Six months after stenting, patient returned for a follow-up visit due to uncontrolled hypertension and high haematocrit levels. Total restenosis of the left renal artery was found. Patient received optical medical treatment and was prescribed to higher doses of hydroxyurea by her treating haematologist. Since then, blood pressure and Hct levels remain adequately controlled. As described by earlier case reports, renal artery stenosis, hypertension and polycythemia often coexist. However, renovascular hypertension may not only lead to secondary erythrocytosis but also be a thrombotic complication of primary erythrocytosis. Thus, patients with polycythaemia vera should be carefully evaluated and optimally managed when hypertension or impaired renal function coexist.
From HeLa cell division to infectious diarrhoea
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stephen, J.; Osborne, M.P.; Spencer, A.J.
1990-09-01
Hela S3 cells were grown in suspension both randomly and, synchronously using hydroxyurea which blocks cells at the G1/S interface. Cryosections were prepared, freeze-dried and analyzed by X-ray microanalysis. As cells moved into S and through M phases (Na) and (Cl) increased; both returned to normal levels upon re-entering G1 phase. The Na/K ratio was 1:1 in G1 phase. Infection of HeLa S3 cells in G1 phase with vaccinia virus resulted in no change in intracellular (Na). Infection of neonatal mice with murine rotavirus was localized to villus tip enterocytes and gave rise to diarrhoea which was maximal at 72hmore » post-infection (p.i.). Diarrhoea was preceded by ischemia of villi (18-42h p.i.) and villus shortening (maximal at 42h p.i.), and was also coincident with a dramatic regrowth of villi. At 48h p.i. a proliferative zone of electron lucent cells was observed in villus base regions. Cryosections of infected gut, taken before, during, and after infection, together with corresponding age-matched controls, were freeze-dried and analysed by X-ray microanalysis. At 48h p.i. electron lucent villus base cells were shown to be more hydrated, and, to contain higher levels of both Na and Cl and lower levels of P, S, K and Mg than corresponding control cells. These studies increase confidence in the use of X-ray microanalysis in studying biological systems, provide some insight into the process of cell division, and constitute the basis of a new concept of diarrhoeal secretion.27 references.« less
The Cellular Phenotype of Roberts Syndrome Fibroblasts as Revealed by Ectopic Expression of ESCO2
van der Lelij, Petra; van Gosliga, Djoke; Oostra, Anneke B.; Steltenpool, Jûrgen; de Groot, Jan; Scheper, Rik J.; Wolthuis, Rob M.; Waisfisz, Quinten; Darroudi, Firouz; Joenje, Hans; de Winter, Johan P.
2009-01-01
Cohesion between sister chromatids is essential for faithful chromosome segregation. In budding yeast, the acetyltransferase Eco1/Ctf7 establishes cohesion during DNA replication in S phase and in response to DNA double strand breaks in G2/M phase. In humans two Eco1 orthologs exist: ESCO1 and ESCO2. Both proteins are required for proper sister chromatid cohesion, but their exact function is unclear at present. Since ESCO2 has been identified as the gene defective in the rare autosomal recessive cohesinopathy Roberts syndrome (RBS), cells from RBS patients can be used to elucidate the role of ESCO2. We investigated for the first time RBS cells in comparison to isogenic controls that stably express V5- or GFP-tagged ESCO2. We show that the sister chromatid cohesion defect in the transfected cell lines is rescued and suggest that ESCO2 is regulated by proteasomal degradation in a cell cycle-dependent manner. In comparison to the corrected cells RBS cells were hypersensitive to the DNA-damaging agents mitomycin C, camptothecin and etoposide, while no particular sensitivity to UV, ionizing radiation, hydroxyurea or aphidicolin was found. The cohesion defect of RBS cells and their hypersensitivity to DNA-damaging agents were not corrected by a patient-derived ESCO2 acetyltransferase mutant (W539G), indicating that the acetyltransferase activity of ESCO2 is essential for its function. In contrast to a previous study on cells from patients with Cornelia de Lange syndrome, another cohesinopathy, RBS cells failed to exhibit excessive chromosome aberrations after irradiation in G2 phase of the cell cycle. Our results point at an S phase-specific role for ESCO2 in the maintenance of genome stability. PMID:19738907
MicroRNA-106b~25 cluster is upregulated in relapsed MLL-rearranged pediatric acute myeloid leukemia
Verboon, Lonneke J.; Obulkasim, Askar; de Rooij, Jasmijn D.E.; Katsman, Jenny E.; Sonneveld, Edwin; Baruchel, André; Trka, Jan; Reinhardt, Dirk; Pieters, Rob; Cloos, Jacqueline; Kaspers, Gertjan J.L.; Klusmann, Jan-Henning; Zwaan, Christian Michel; Fornerod, Maarten; van den Heuvel-Eibrink, Marry M.
2016-01-01
The most important reason for therapy failure in pediatric acute myeloid leukemia (AML) is relapse. In order to identify miRNAs that contribute to the clonal evolution towards relapse in pediatric AML, miRNA expression profiling of 127 de novo pediatric AML cases were used. In the diagnostic phase, no miRNA signatures could be identified that were predictive for relapse occurrence, in a large pediatric cohort, nor in a nested mixed lineage leukemia (MLL)-rearranged pediatric cohort. AML with MLL- rearrangements are found in 15-20% of all pediatric AML samples, and reveal a relapse rate up to 50% for certain translocation partner subgroups. Therefore, microRNA expression profiling of six paired initial diagnosis-relapse MLL-rearranged pediatric AML samples (test cohort) and additional eight paired initial diagnosis-relapse samples with MLL-rearrangements (validation cohort) was performed. A list of 53 differentially expressed miRNAs was identified of which the miR-106b~25 cluster, located in intron 13 of MCM7, was the most prominent. These differentially expressed miRNAs however could not predict a relapse in de novo AML samples with MLL-rearrangements at diagnosis. Furthermore, higher mRNA expression of both MCM7 and its upstream regulator E2F1 was found in relapse samples with MLL-rearrangements. In conclusion, we identified the miR-106b~25 cluster to be upregulated in relapse pediatric AML with MLL-rearrangements. PMID:27351222
Chenault, Kristin; Moga, Michael-Alice; Shin, Minah; Petersen, Emily; Backer, Carl; De Oliveira, Gildasio S; Suresh, Santhanam
2016-05-01
Transfer of patient care among clinicians (handovers) is a common source of medical errors. While the immediate efficacy of these initiatives is well documented, sustainability of practice changes that results in better processes of care is largely understudied. The objective of the current investigation was to evaluate the sustainability of a protocolized handover process in pediatric patients from the operating room after cardiac surgery to the intensive care unit. This was a prospective study with direct observation assessment of handover performance conducted in the cardiac ICU (CICU) of a free-standing, tertiary care children's hospital in the United States. Patient transitions from the operating room to the CICU, including the verbal handoff, were directly observed by a single independent observer in all phases of the study. A checklist of key elements identified errors classified as: (1) technical, (2) information omissions, and (3) realized errors. Total number of errors was compared across the different times of the study (preintervention, postintervention, and the current sustainability phase). A total of 119 handovers were studied: 41 preintervention, 38 postintervention, and 40 in the current sustainability phase. The median [Interquartile range (IQR)] number of technical errors was significantly reduced in the sustainability phase compared to the preintervention and postintervention phase, 2 (1-3), 6 (5-7), and 2.5 (2-4), respectively P = 0.0001. Similarly, the median (IQR) number of verbal information omissions was also significantly reduced in the sustainability phase compared to the preintervention and postintervention phases, 1 (1-1), 4 (3-5) and 2 (1-3), respectively. We demonstrate sustainability of an improved handover process using a checklist in children being transferred to the intensive care unit after cardiac surgery. Standardized handover processes can be a sustainable strategy to improve patient safety after pediatric cardiac surgery. © 2016 John Wiley & Sons Ltd.
Pediatric multiple sclerosis: Clinical features and outcome.
Waldman, Amy; Ness, Jayne; Pohl, Daniela; Simone, Isabella Laura; Anlar, Banu; Amato, Maria Pia; Ghezzi, Angelo
2016-08-30
Multiple sclerosis (MS) in children manifests with a relapsing-remitting MS (RRMS) disease course. Acute relapses consist of new neurologic deficits persisting greater than 24 hours, in the absence of intercurrent illness, and occur with a higher frequency early in the disease as compared to adult-onset RRMS. Most pediatric patients with MS recover well from these early relapses, and cumulative physical disability is rare in the first 10 years of disease. Brainstem attacks, poor recovery from a single attack, and a higher frequency of attacks portend a greater likelihood of future disability. Although prospective pediatric-onset MS cohorts have been established in recent years, there remains very limited prospective data detailing the longer-term clinical outcome of pediatric-onset MS into adulthood. Whether the advent of MS therapies, and the largely off-label access to such therapies in pediatric MS, has improved prognosis is unknown. MS onset during the key formative academic years, concurrent with active cognitive maturation, is an important determinant of long-term outcome, and is discussed in detail in another article in this supplement. Finally, increasing recognition of pediatric MS worldwide, recent launch of phase III trials for new agents in the pediatric MS population, and the clear imperative to more fully appreciate health-related quality of life in pediatric MS through adulthood highlight the need for standardized, validated, and robust outcome measures. © 2016 American Academy of Neurology.
Pastores, Gregory M; Petakov, Milan; Giraldo, Pilar; Rosenbaum, Hanna; Szer, Jeffrey; Deegan, Patrick B; Amato, Dominick J; Mengel, Eugen; Tan, Ee Shien; Chertkoff, Raul; Brill-Almon, Einat; Zimran, Ari
2014-12-01
Taliglucerase alfa is a β-glucosidase enzyme replacement therapy (ERT) approved in the US and other countries for the treatment of Gaucher disease (GD) in adults and is approved in pediatric and adult patients in Australia and Canada. It is the first approved plant cell-expressed recombinant human protein. A Phase 3, multicenter, open-label, 9-month study assessed safety and efficacy of switching to taliglucerase alfa in adult and pediatric patients with GD treated with imiglucerase for at least the previous 2years. Patients with stable disease were offered taliglucerase alfa treatment using the same dose (9-60U/kg body weight) and regimen of administration (every 2weeks) as imiglucerase. This report summarizes results from 26 adult and 5 pediatric patients who participated in the trial. Disease parameters (spleen and liver volumes, hemoglobin concentration, platelet count, and biomarker levels) remained stable through 9months of treatment in adults and children following the switch from imiglucerase. All treatment-related adverse events were mild or moderate in severity and transient in nature. Exploratory parameters of linear growth and development showed positive outcomes in pediatric patients. These findings provide evidence of the efficacy and safety profile of taliglucerase alfa as an ERT for GD in patients previously treated with imiglucerase. This trial was registered at www.clinicaltrials.gov as # NCT00712348. Copyright © 2014 Elsevier Inc. All rights reserved.
Efficacy of an Interinstitutional Mentoring Program Within Pediatric Rheumatology.
Moorthy, Lakshmi Nandini; Muscal, Eyal; Riebschleger, Meredith; Klein-Gitelman, Marisa; Nigrovic, Lise E; Horon, Jeffrey R; Rouster-Stevens, Kelly; Ferguson, Polly J; Eberhard, B Anne; Brunner, Hermine I; Prahalad, Sampath; Schneider, Rayfel; Nigrovic, Peter A
2016-05-01
The small size of many pediatric rheumatology programs translates into limited mentoring options for early career physicians. To address this problem, the American College of Rheumatology (ACR) and the Childhood Arthritis and Rheumatology Research Alliance (CARRA) developed a subspecialty-wide interinstitutional mentoring program, the ACR/CARRA Mentoring Interest Group (AMIGO). We sought to assess the impact of this program on mentoring within pediatric rheumatology. In a longitudinal 3-year study, participant ratings from the AMIGO pilot program were compared with those after the program was opened to general enrollment. Access to mentoring as a function of career stage was assessed by surveys of the US and Canadian pediatric rheumatologists in 2011 and 2014, before and after implementation of AMIGO. Participants in the pilot phase (19 dyads) and the general implementation phase (112 dyads) reported comparable success in establishing mentor contact, suitability of mentor-mentee pairing, and benefit with respect to career development, scholarship, and work-life balance. Community surveys showed that AMIGO participation as mentee was high among fellows (86%) and modest among junior faculty (31%). Implementation correlated with significant gains in breadth of mentorship and in overall satisfaction with mentoring for fellows but not junior faculty. AMIGO is a career mentoring program that serves most fellows and many junior faculty in pediatric rheumatology across the US and Canada. Program evaluation data confirm that a subspecialty-wide interinstitutional mentoring program is feasible and can translate into concrete improvement in mentoring, measurable at the level of the whole professional community. © 2016, American College of Rheumatology.
Raal, Frederick J; Braamskamp, Marjet J; Selvey, Sheryl L; Sensinger, Charlotte H; Kastelein, John J
2016-01-01
Homozygous familial hypercholesterolemia (HoFH) is a rare, inherited condition resulting in severely elevated low-density lipoprotein cholesterol levels (LDL-C) leading to premature cardiovascular disease and, often, death. Mipomersen is an antisense oligonucleotide that inhibits apolipoprotein B (apo B) synthesis, lowering LDL-C levels. Mipomersen has demonstrated efficacy in adult HoFH patients, possibly providing a therapeutic option for pediatric patients. Study objectives were to summarize mipomersen efficacy and safety in the pediatric cohort of a phase 3 randomized controlled trial (RCT) and subsequent open-label extension study (OLE). Seven patients aged 12-18 years were randomized to 200-mg mipomersen or placebo weekly (26 weeks) and received mipomersen in the OLE (52 or 104 weeks). Plasma LDL-C and apo B concentrations and adverse events were assessed. All pediatric patients completed the RCT and entered OLE. The 3 mipomersen patients in the RCT experienced mean reductions from baseline to RCT end of 42.7% and 46.1% for LDL-C and apo B, respectively. Of the 4 placebo patients, 3 responded well to mipomersen during OLE, with reductions in LDL-C of 26.5%-42.1%. Three patients completed OLE treatment, and 4 patients discontinued therapy due to adverse events. Lipid level fluctuations were observed and were likely due to poor compliance. Long-term mipomersen treatment was successful regarding efficacy parameters for pediatric HoFH patients. The safety profile was consistent with other phase 3 clinical trials. Long-term compliance was an issue. Measures supporting adherence should be encouraged. Copyright © 2016 Sanofi-Genzyme. Published by Elsevier Inc. All rights reserved.
Kabani, Sarah; Waterfall, Martin; Matthews, Keith R
2010-01-01
Studies on the cell-cycle of Trypanosoma brucei have revealed several unusual characteristics that differ from the model eukaryotic organisms. However, the inability to isolate homogenous populations of parasites in distinct cell-cycle stages has limited the analysis of trypanosome cell division and complicated the understanding of mutant phenotypes with possible impact on cell-cycle related events. Although hydroxyurea-induced cell-cycle arrest in procyclic and bloodstream forms has been applied recently with success, such block-release protocols can complicate the analysis of cell-cycle regulated events and have the potential to disrupt important cell-cycle checkpoints. An alternative approach based on flow cytometry of parasites stained with Vybrant DyeCycle Orange circumvents this problem, but is restricted to procyclic form parasites. Here, we apply Vybrant Dyecycle Violet staining coupled with flow cytometry to effectively select different cell-cycle stages of bloodstream form trypanosomes. Moreover, the sorted parasites remain viable, although synchrony is rapidly lost. This method enables cell-cycle enrichment of populations of trypanosomes in their mammal infective stage, particularly at the G1 phase.
Kabani, Sarah; Waterfall, Martin; Matthews, Keith R.
2010-01-01
Studies on the cell-cycle of Trypanosoma brucei have revealed several unusual characteristics that differ from the model eukaryotic organisms. However, the inability to isolate homogenous populations of parasites in distinct cell-cycle stages has limited the analysis of trypanosome cell division and complicated the understanding of mutant phenotypes with possible impact on cell-cycle related events. Although hydroxyurea-induced cell-cycle arrest in procyclic and bloodstream forms has been applied recently with success, such block-release protocols can complicate the analysis of cell-cycle regulated events and have the potential to disrupt important cell-cycle checkpoints. An alternative approach based on flow cytometry of parasites stained with Vybrant DyeCycle Orange circumvents this problem, but is restricted to procyclic form parasites. Here, we apply Vybrant Dyecycle Violet staining coupled with flow cytometry to effectively select different cell-cycle stages of bloodstream form trypanosomes. Moreover, the sorted parasites remain viable, although synchrony is rapidly lost. This method enables cell-cycle enrichment of populations of trypanosomes in their mammal infective stage, particularly at the G1 phase. PMID:19729042
FANCJ/BRIP1 recruitment and regulation of FANCD2 in DNA damage responses
Zhang, Fan; Fan, Qiang; Ren, Keqin; Auerbach, Arleen D.; Andreassen, Paul R.
2016-01-01
FANCJ/BRIP1 encodes a helicase that has been implicated in the maintenance of genomic stability. Here, to better understand FANCJ function in DNA damage responses, we have examined the regulation of its cellular localization. FANCJ nuclear foci assemble spontaneously during S phase and are induced by various stresses. FANCJ foci colocalize with the replication fork following treatment with hydroxyurea, but not spontaneously. Using FANCJ mutants, we find that FANCJ helicase activity and the capacity to bind BRCA1 are both involved in FANCJ recruitment. Given similarities to the recruitment of another Fanconi anemia protein, FANCD2, we tested for colocalization of FANCJ and FANCD2. Importantly, these proteins show substantial colocalization, and FANCJ promotes the assembly of FANCD2 nuclear foci. This process is linked to the proper localization of FANCJ itself since both FANCJ and FANCD2 nuclear foci are compromised by FANCJ mutants that abrogate its helicase activity or interaction with BRCA1. Our results suggest that FANCJ is recruited in response to replication stress and that FANCJ/BRIP1 may serve to link FANCD2 to BRCA1. PMID:20676667
Genome-wide expression profiling in pediatric septic shock
Wong, Hector R.
2013-01-01
For nearly a decade, our research group has had the privilege of developing and mining a multi-center, microarray-based, genome-wide expression database of critically ill children (≤ 10 years of age) with septic shock. Using bioinformatic and systems biology approaches, the expression data generated through this discovery-oriented, exploratory approach have been leveraged for a variety of objectives, which will be reviewed. Fundamental observations include wide spread repression of gene programs corresponding to the adaptive immune system, and biologically significant differential patterns of gene expression across developmental age groups. The data have also identified gene expression-based subclasses of pediatric septic shock having clinically relevant phenotypic differences. The data have also been leveraged for the discovery of novel therapeutic targets, and for the discovery and development of novel stratification and diagnostic biomarkers. Almost a decade of genome-wide expression profiling in pediatric septic shock is now demonstrating tangible results. The studies have progressed from an initial discovery-oriented and exploratory phase, to a new phase where the data are being translated and applied to address several areas of clinical need. PMID:23329198
The Impact of Cancer and its Treatment on the Growth and Development of the Pediatric Patient.
Brand, Sarah; Wolfe, Joanne; Samsel, Chase
2017-01-01
Cancer treatment can have profound effects on the growth and development of pediatric patients. Different models of psychosocial development and behavioral treatment approaches aid children receiving medical treatment. Providing education, anticipatory guidance, and individualized support to child and their families is a psychosocial standard. Clarify the different models of psychosocial development and applicable psychosocial interventions to better prepare and tailor cancer treatment to pediatric patients. Authors reviewed existing evidenced-based literature in oncology, psychology, developmental, and psychiatric while drawing on case examples and expert knowledge to illustrate the impact of cancer treatment on pediatric patients, analyze developmentally individualized needs, and describe facilitative interventions. Pediatric patients of all ages cope and adjust better to all phases of treatment when their care is delivered in a developmentally-informed and psychosocially thoughtful way. Providers can comprehensively prepare their patients and families for treatment better by utilizing a psychosocially- and developmentally-informed framework while meeting individualized unique needs of patients. An integrated multidisciplinary psychosocial support team is facilitative in anticipating and meeting the needs of pediatric cancer patients and has recently become a psychosocial standard of care. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Narus, Scott P.; Srivastava, Rajendu; Gouripeddi, Ramkiran; Livne, Oren E.; Mo, Peter; Bickel, Jonathan P.; de Regt, David; Hales, Joseph W.; Kirkendall, Eric; Stepanek, Richard L.; Toth, Jamie; Keren, Ron
2011-01-01
Integrating clinical data with administrative data across disparate electronic medical record systems will help improve the internal and external validity of comparative effectiveness research. The Pediatric Health Information System (PHIS) currently collects administrative information from 43 pediatric hospital members of the Child Health Corporation of America (CHCA). Members of the Pediatric Research in Inpatient Settings (PRIS) network have partnered with CHCA and the University of Utah Biomedical Informatics Core to create an enhanced version of PHIS that includes clinical data. A specialized version of a data federation architecture from the University of Utah (“FURTHeR”) is being developed to integrate the clinical data from the member hospitals into a common repository (“PHIS+”) that is joined with the existing administrative data. We report here on our process for the first phase of federating lab data, and present initial results. PMID:22195159
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ainsworth, William B.; Hughes, Bridget Todd; Au, Wei Chun
2013-10-04
Highlights: •Hug1p overexpression sensitizes wild-type cells to DNA damage and hydroxyurea (HU). •Expression of Hug1p in response to HU treatment is delayed relative to Rnr3p. •MEC1 pathway genes are required for cytoplasmic localization of Hug1p. •Hug1p subcellular compartmentalization to the cytoplasm coincides with Rnr2p–Rnr4p. -- Abstract: The evolutionarily conserved MEC1 checkpoint pathway mediates cell cycle arrest and induction of genes including the RNR (Ribonucleotide reductase) genes and HUG1 (Hydroxyurea, ultraviolet, and gamma radiation) in response to DNA damage and replication arrest. Rnr complex activity is in part controlled by cytoplasmic localization of the Rnr2p–Rnr4p subunits and inactivation of negative regulatorsmore » Sml1p and Dif1p upon DNA damage and hydroxyurea (HU) treatment. We previously showed that a deletion of HUG1 rescues lethality of mec1Δ and suppresses dun1Δ strains. In this study, multiple approaches demonstrate the regulatory response of Hug1p to DNA damage and HU treatment and support its role as a negative effector of the MEC1 pathway. Consistent with our hypothesis, wild-type cells are sensitive to DNA damage and HU when HUG1 is overexpressed. A Hug1 polyclonal antiserum reveals that HUG1 encodes a protein in budding yeast and its MEC1-dependent expression is delayed compared to the rapid induction of Rnr3p in response to HU treatment. Cell biology and subcellular fractionation experiments show localization of Hug1p-GFP to the cytoplasm upon HU treatment. The cytoplasmic localization of Hug1p-GFP is dependent on MEC1 pathway genes and coincides with the cytoplasmic localization of Rnr2p–Rnr4p. Taken together, the genetic interactions, gene expression, and localization studies support a novel role for Hug1p as a negative regulator of the MEC1 checkpoint response through its compartmentalization with Rnr2p–Rnr4p.« less
Zohaib, Muhammad; Ansari, Saqib H; Hashim, Zehra; Shamsi, Tahir S; Zarina, Shamshad
2016-07-01
β-Thalassemia is the most common hereditary disorder characterized by reduced production of β-globin chains of hemoglobin A (HbA). In recent years, hydroxyurea (HU) has shown promising therapeutic benefits in patients with β-thalassemia by fetal hemoglobin augmentation. We have analyzed effects of hydroxyurea treatment on oxidative stress in β-thalassemia patients by assessing activities of paraoxonase (PON) and arylesterase along with malondialdehyde (MDA) and total reactive oxygen species (ROS) concentrations. Blood samples from 159 individuals including 56 HU-treated and 58 untreated β-thalassemia patients and 45 healthy controls were analyzed. PON activity was found to be highest in healthy individuals (177.76 ± 4.44 U/mL) as compared to treated (52.67 ± 3.65 U/mL) and untreated (55.11 ± 3.26 U/mL) patients. A similar trend was observed in the case of arylesterase activity in normal, β-thalassemia-treated, and untreated (210.0 ± 11.25 U/mL, 163.03 ± 9.04 U/mL, 139.77 ± 10.10 U/mL) subjects. Serum MDA concentrations (2.59 ± 0.09 nmol/mL, 2.45 ± 0.08 nmol/mL, and 1.15 ± 0.05 nmol/mL) and total ROS concentrations (3.73 ± 0.20 nmol/mL, 3.54 ± 0.23 nmol/mL, and 2.45 ± 0.14 nmol/mL) were significantly elevated in both groups (untreated and treated) as compared to healthy individuals (P < .01). Oxidative stress was found to be markedly elevated in β-thalassemia patients as compared to healthy controls. Insignificant differences were, however, observed in mean concentrations of PON1 paraoxonase and arylesterase activities, serum MDA concentration and total ROS concentrations between HU-treated and untreated patients. We propose that HU therapy alone seems to be ineffective in managing oxidative stress and is likely to offer a better clinical outcome when supplemented with efficient iron chelation therapy and antioxidants. © 2015, The American College of Clinical Pharmacology.
Ladra, Matthew M.; Edgington, Samantha K.; Mahajan, Anita; Grosshans, David; Szymonifka, Jackie; Khan, Fazal; Moteabbed, Maryam; Friedmann, Alison M.; MacDonald, Shannon M.; Tarbell, Nancy J.; Yock, Torunn I.
2015-01-01
Background Pediatric rhabdomyosarcoma (RMS) is highly curable, however, cure may come with significant radiation related toxicity in developing tissues. Proton therapy (PT) can spare excess dose to normal structures, potentially reducing the incidence of adverse effects. Methods Between 2005 and 2012, 54 patients were enrolled on a prospective multi-institutional phase II trial using PT in pediatric RMS. As part of the protocol, intensity modulated radiation therapy (IMRT) plans were generated for comparison with clinical PT plans. Results Target coverage was comparable between PT and IMRT plans with a mean CTV V95 of 100% for both modalities (p=0.82). However, mean integral dose was 1.8 times higher for IMRT (range 1.0-4.9). By site, mean integral dose for IMRT was 1.8 times higher for H&N (p<0.01) and GU (p=0.02), 2.0 times higher for trunk/extremity (p<0.01), and 3.5 times higher for orbit (p<0.01) compared to PT. Significant sparing was seen with PT in 26 of 30 critical structures assessed for orbital, head and neck, pelvic, and trunk/extremity patients. Conclusions Proton radiation lowers integral dose and improves normal tissue sparing when compared to IMRT for pediatric RMS. Correlation with clinical outcomes is necessary once mature long-term toxicity data are available. PMID:25443861
Lee, Sae Mi; Kim, Yae Jean; Yoo, Keon Hee; Sung, Ki Woong; Koo, Hong Hoe; Kang, Eun Suk
2017-05-01
Cytomegalovirus (CMV) is a well-established cause of morbidity and mortality in pediatric recipients of allogeneic hematopoietic stem cell transplantation (allo-HSCT). CD8⁺ T-cells are important for controlling CMV infection. We conducted a prospective pilot study to investigate the clinical utility of measuring the CMV-specific T-cell immune response using the QuantiFERON-CMV assay (QF-CMV) in pediatric allo-HSCT recipients. Overall, 16 of 25 (64%) patients developed CMV infection. QF-CMV was evaluated in these 16 patients during the early and late phases of the first CMV infection post allo-HSCT. Whereas the initial QF-CMV results during the early phase of CMV infection did not correlate with the course of the corresponding infection, the QF-CMV results post resolution of the first CMV infection correlated with the recurrence of CMV infection until 12 months post allo-HSCT; no recurrent infections occurred in the four QF-CMV-positive patients, while recurrent infections manifested in five of eight QF-CMV-negative (62.5%) and all three QF-CMV-indeterminate patients (P=0.019). In spite of the small number of patients examined, this study supports the potential application of monitoring CMV-specific T-cell immunity using the QF-CMV assay to predict the recurrence of CMV infection in pediatric allo-HSCT recipients. © The Korean Society for Laboratory Medicine.
Phase I Trial and Pharmacokinetic Study of Lexatumumab in Pediatric Patients With Solid Tumors
Merchant, Melinda S.; Geller, James I.; Baird, Kristin; Chou, Alexander J.; Galli, Susana; Charles, Ava; Amaoko, Martha; Rhee, Eunice H.; Price, Anita; Wexler, Leonard H.; Meyers, Paul A.; Widemann, Brigitte C.; Tsokos, Maria; Mackall, Crystal L.
2012-01-01
Purpose Lexatumumab is an agonistic, fully human monoclonal antibody against tumor necrosis factor–related apoptosis-inducing ligand receptor 2 with preclinical evidence of activity in pediatric solid tumors. Patients and Methods This phase I dose-escalation study examined the safety, tolerability, pharmacokinetics, and immunogenicity of lexatumumab at doses up to, but not exceeding, the adult maximum-tolerated dose (3, 5, 8, and 10 mg/kg), administered once every 2 weeks to patients age ≤ 21 years with recurrent or progressive solid tumors. Results Twenty-four patients received a total of 56 cycles of lexatumumab over all four planned dose levels. One patient had grade 2 pericarditis consistent with radiation recall, and one patient developed grade 3 pneumonia with hypoxia during the second cycle. Five patients experienced stable disease for three to 24 cycles. No patients experienced complete or partial response, but several showed evidence of antitumor activity, including one patient with recurrent progressive osteosarcoma who experienced resolution of clinical symptoms and positron emission tomography activity, ongoing more than 1 year off therapy. One patient with hepatoblastoma showed a dramatic biomarker response. Conclusion Pediatric patients tolerate 10 mg/kg of lexatumumab administered once every 14 days, the maximum-tolerated dose identified in adults. The drug seems to mediate some clinical activity in pediatric solid tumors and may work with radiation to enhance antitumor effects. PMID:23071222
Yoshida, Hideki; Imamura, Toshihiko; Saito, Akiko M.; Takahashi, Yoshihiro; Suenobu, So-ichi; Hasegawa, Daiichiro; Deguchi, Takao; Hashii, Yoshiko; Kawasaki, Hirohide; Endo, Mikiya; Hori, Hiroki; Suzuki, Nobuhiro; Kosaka, Yoshiyuki; Kato, Koji; Yumura-Yagi, Keiko; Hara, Junichi; Oda, Megumi; Sato, Atsushi; Horibe, Keizo
2015-01-01
Although L-asparaginase related hyperglycemia is well known adverse event, it is not studied whether the profile of this adverse event is affected by intensification of L-asparaginase administration. Here, we analyzed the profile of L-asparaginase related hyperglycemia in a 1,176 patients with pediatric acute lymphoblastic leukemia treated according to the Japan Association of Childhood Leukemia Study ALL-02 protocol using protracted L-asparaginase administration in maintenance phase. We determined that a total of 75 L-asparaginase related hyperglycemia events occurred in 69 patients. Although 17 events (17/1176, 1.4%) developed in induction phase, which was lower incidence than those (10–15%) in previous reports, 45 events developed during the maintenance phase with protracted L-asparaginase administration. Multivariate analysis showed that older age at onset (≥10 years) was a sole independent risk factor for L-asparaginase-related hyperglycemia (P<0.01), especially in maintenance phase. Contrary to the previous reports, obesity was not associated with L-asparaginase-related hyperglycemia. These findings suggest that protracted administration of L-asparaginase is the risk factor for hyperglycemia when treating adolescent and young adult acute lymphoblastic leukemia patients. PMID:26317422
Siegel, Stuart E; Stock, Wendy; Johnson, Rebecca H; Advani, Anjali; Muffly, Lori; Douer, Dan; Reed, Damon; Lewis, Mark; Freyer, David R; Shah, Bijal; Luger, Selina; Hayes-Lattin, Brandon; Jaboin, Jerry J; Coccia, Peter F; DeAngelo, Daniel J; Seibel, Nita; Bleyer, Archie
2018-05-01
The incidence of acute lymphoblastic leukemia (ALL) and lymphoblastic lymphoma (LBL) in adolescent and young adult (AYA) patients (age range, 15-39 years) in the United States is increasing at a greater rate than in younger or older persons. Their optimal treatment has been increasingly debated as pediatric regimens have become more widely used in the age group. This review compares the basic features of pediatric and adult chemotherapy regimens for ALL and LBL, recognizes and describes the challenges of the pediatric regimen, and suggests strategies to facilitate its adoption for AYAs with ALL and LBL. All but 2 of 25 published comparisons of outcomes with pediatric and adult regimens for ALL and LBL in AYAs and 1 meta-analysis favor the pediatric regimen. After more than a half-century of clinical trials of the pediatric regimens, including at least 160 phase 3 trials in the United States, the pediatric regimens have become far more complex than most adult regimens. Asparaginase, a critical component of the pediatric regimens, is more difficult to administer to AYAs (and older patients) but nonetheless has a favorable benefit to toxicity ratio for AYAs. A dramatic reduction in outcome of ALL and LBL during the AYA years (the "survival cliff") is coincident with similar reductions in proportions of AYAs referred to academic centers and enrolled on clinical trials (the "accrual cliff" and "referral cliff"). The accumulating data increasingly support treating AYAs with ALL and LBL with a pediatric-inspired regimen or an approved institutional or national clinical trial tailored for this patient group. A need to develop clinical trials specifically for AYAs and to encourage their participation is paramount, with a goal to improve both the quantity and quality of survival.
Restoration of energy level in the early phase of acute pediatric pancreatitis.
Mosztbacher, Dóra; Farkas, Nelli; Solymár, Margit; Pár, Gabriella; Bajor, Judit; Szűcs, Ákos; Czimmer, József; Márta, Katalin; Mikó, Alexandra; Rumbus, Zoltán; Varjú, Péter; Hegyi, Péter; Párniczky, Andrea
2017-02-14
Acute pancreatitis (AP) is a serious inflammatory disease with rising incidence both in the adult and pediatric populations. It has been shown that mitochondrial injury and energy depletion are the earliest intracellular events in the early phase of AP. Moreover, it has been revealed that restoration of intracellular ATP level restores cellular functions and defends the cells from death. We have recently shown in a systematic review and meta-analysis that early enteral feeding is beneficial in adults; however, no reviews are available concerning the effect of early enteral feeding in pediatric AP. In this minireview, our aim was to systematically analyse the literature on the treatment of acute pediatric pancreatitis. The preferred reporting items for systematic review (PRISMA-P) were followed, and the question was drafted based on participants, intervention, comparison and outcomes: P: patients under the age of twenty-one suffering from acute pancreatitis; I: early enteral nutrition (per os and nasogastric- or nasojejunal tube started within 48 h); C: nil per os therapy; O: length of hospitalization, need for treatment at an intensive care unit, development of severe AP, lung injury (including lung oedema and pleural effusion), white blood cell count and pain score on admission. Altogether, 632 articles (PubMed: 131; EMBASE: 501) were found. After detailed screening of eligible papers, five of them met inclusion criteria. Only retrospective clinical trials were available. Due to insufficient information from the authors, it was only possible to address length of hospitalization as an outcome of the study. Our mini-meta-analysis showed that early enteral nutrition significantly (SD = 0.806, P = 0.034) decreases length of hospitalization compared with nil per os diet in acute pediatric pancreatitis. In this minireview, we clearly show that early enteral nutrition, started within 24-48 h, is beneficial in acute pediatric pancreatitis. Prospective studies and better presentation of research are crucially needed to achieve a higher level of evidence.
Restoration of energy level in the early phase of acute pediatric pancreatitis
Mosztbacher, Dóra; Farkas, Nelli; Solymár, Margit; Pár, Gabriella; Bajor, Judit; Szűcs, Ákos; Czimmer, József; Márta, Katalin; Mikó, Alexandra; Rumbus, Zoltán; Varjú, Péter; Hegyi, Péter; Párniczky, Andrea
2017-01-01
Acute pancreatitis (AP) is a serious inflammatory disease with rising incidence both in the adult and pediatric populations. It has been shown that mitochondrial injury and energy depletion are the earliest intracellular events in the early phase of AP. Moreover, it has been revealed that restoration of intracellular ATP level restores cellular functions and defends the cells from death. We have recently shown in a systematic review and meta-analysis that early enteral feeding is beneficial in adults; however, no reviews are available concerning the effect of early enteral feeding in pediatric AP. In this minireview, our aim was to systematically analyse the literature on the treatment of acute pediatric pancreatitis. The preferred reporting items for systematic review (PRISMA-P) were followed, and the question was drafted based on participants, intervention, comparison and outcomes: P: patients under the age of twenty-one suffering from acute pancreatitis; I: early enteral nutrition (per os and nasogastric- or nasojejunal tube started within 48 h); C: nil per os therapy; O: length of hospitalization, need for treatment at an intensive care unit, development of severe AP, lung injury (including lung oedema and pleural effusion), white blood cell count and pain score on admission. Altogether, 632 articles (PubMed: 131; EMBASE: 501) were found. After detailed screening of eligible papers, five of them met inclusion criteria. Only retrospective clinical trials were available. Due to insufficient information from the authors, it was only possible to address length of hospitalization as an outcome of the study. Our mini-meta-analysis showed that early enteral nutrition significantly (SD = 0.806, P = 0.034) decreases length of hospitalization compared with nil per os diet in acute pediatric pancreatitis. In this minireview, we clearly show that early enteral nutrition, started within 24-48 h, is beneficial in acute pediatric pancreatitis. Prospective studies and better presentation of research are crucially needed to achieve a higher level of evidence. PMID:28246469
Breitwieser, Carrie L; Vaughn, Lisa M
2014-01-01
A photovoice project was conducted with pediatric bone marrow transplant (BMT) patients to examine their coping skills and interpretation of their experience during a BMT, especially when hospitalized. We also wanted to determine how photovoice could be used within a pediatric BMT unit. Sixteen children (ages 4-14) and 2 young adults (ages 22 and 25) from a pediatric BMT unit participated in the project. Six BMT outpatients participated in the data analysis and evaluation phase. Fourteen clinical staff evaluated the impact of the project on their practice. Three primary themes emerged from the pre- and post-BMT photos, accompanying detailed notes, and BMT outpatient analysis of the photos: (a) BMT is "torture," (b) BMT is "time slipping away," and (c) BMT requires normalization, comfort, distraction, and support. BMT patients and staff concluded that photovoice helped express and release emotions regarding the challenges of BMT. BMT staff noted that the results of this project reminded them of the importance of being patient-centered and mindful of patient experience and the therapeutic relationship. © 2014 by Association of Pediatric Hematology/Oncology Nurses.
Lindaman, L M
2001-01-01
Just as pediatric fractures and bones are basically similar to adult fractures and bones, pediatric bone healing is basically similar to adult bone healing. They both go through the three same phases of inflammation, reparation, and remodeling. It is those differences between pediatric and adult bone, however, that affect the differences in the healing of pediatric bone. Because pediatric bone can fail in compression, less initial stability and less callus formation is required to achieve a clinically stable or healed fracture. The greater subperiosteal hematoma and the stronger periosteum all contribute to a more rapid formation of callous strong enough to render the fracture healed more rapidly than the adult. Genes and hormones that are necessary for the initial formation of the skeleton are the same as, or at least similar in most instances, to those necessary for the healing of fractures. This osteogenic environment of the pediatric bone means that these fracture healing processes are already ongoing in the child at the time of the fracture. In the adult, these factors must be reawakened, leading to the slower healing time in the adult. Once the fracture is healed, the still-growing pediatric bone can correct any "sins" of fracture alignment or angulation leaving the bone with no signs of having ever been broken. The final result is bone that is, in the child's words, "as good as new."
Severe pediatric Graves orbitopathy in adolescents of African origin.
Papp, Andrea; Vasserot-Merle, Clemence; Dorner, Guido; Paridaens, Dion
2016-12-01
This article reports on two cases of severe pediatric Graves orbitopathy (GO) in two adolescents of African origin. Two black male adolescents presented with highly active GO and signs of beginning compressive optic neuropathy. Neither of them were smokers nor had a family history of GO. Besides urgent referral to pediatric endocrinologists, intravenous methylprednisolon pulse therapy was initiated. In spite of the fluctuating thyroid hormone levels in the initial phase of antithyroid therapy, intravenous steroid administration stopped the progression of malignant GO rapidly in both of our patients without any considerable side effects. Although the course of GO during childhood is considered to be mild, severe, sight threatening GO-requiring immunosuppression-may occur at young age, as in the reported adolescent patients of African descent.
Jison, Maria L.; Munson, Peter J.; Barb, Jennifer J.; Suffredini, Anthony F.; Talwar, Shefali; Logun, Carolea; Raghavachari, Nalini; Beigel, John H.; Shelhamer, James H.; Danner, Robert L.; Gladwin, Mark T.
2016-01-01
In sickle cell disease, deoxygenation of intra-erythrocytic hemoglobin S leads to hemoglobin polymerization, erythrocyte rigidity, hemolysis, and microvascular occlusion. Ischemia-reperfusion injury, plasma hemoglobin-mediated nitric oxide consumption, and free radical generation activate systemic inflammatory responses. To characterize the role of circulating leukocytes in sickle cell pathogenesis we performed global transcriptional analysis of blood mononuclear cells from 27 patients in steady-state sickle cell disease (10 patients treated and 17 patients untreated with hydroxyurea) compared with 13 control subjects. We used gender-specific gene expression to validate human microarray experiments. Patients with sickle cell disease demonstrated differential gene expression of 112 genes involved in heme metabolism, cell-cycle regulation, antioxidant and stress responses, inflammation, and angiogenesis. Inducible heme oxygenase-1 and downstream proteins biliverdin reductase and p21, a cyclin-dependent kinase, were up-regulated, potentially contributing to phenotypic heterogeneity and absence of atherosclerosis in patients with sickle cell disease despite endothelial dysfunction and vascular inflammation. Hydroxyurea therapy did not significantly affect leukocyte gene expression, suggesting that such therapy has limited direct anti-inflammatory activity beyond leukoreduction. Global transcriptional analysis of circulating leukocytes highlights the intense oxidant and inflammatory nature of steady-state sickle cell disease and provides insight into the broad compensatory responses to vascular injury. PMID:15031206
Karimi, Mehran; Zarei, Tahereh; Haghpanah, Sezaneh; Moghadam, Mohamad; Ebrahimi, Ahmad; Rezaei, Narges; Heidari, Ghazaleh; Vazin, Afsaneh; Khavari, Maryam; Miri, Hamid R
2017-05-01
To evaluate the possible relationship between hydroxyurea (HU) response and some single-nucleotide polymorphism (SNP) in patients affected by β-thalassemia intermedia. In this cross-sectional study, 100 β-thalassemia intermedia patients who were taking HU with a dose of 8 to 15 mg/kg body weight per day for a period of at least 6 months were randomly selected between February 2013 and October 2014 in southern Iran. HU response was defined based on decrease or cessation of the blood transfusion need and evaluation of Hb level. In univariate analysis, from all evaluated SNPs, only rs10837814 SNP of olfactory receptors (ORs) OR51B2 showed a significant association with HU response (P=0.038) and from laboratory characteristics, only nucleated red blood cells showed significant associations (116%±183%) in good responders versus (264%±286%) in poor responders (P=0.045). In multiple logistic regression, neither laboratory variables nor different SNPs, showed significant association with HU response. Three novel nucleotide variations (-665 [A→C], -1301 [T→G],-1199 delA) in OR51B2 gene were found in good responders. None of the evaluated SNPs in our study showed significant association with HU response. Further larger studies and evaluation of other genes are suggested.
Hydroxyurea for hemoglobin E/β-thalassemia: a systematic review and meta-analysis.
Algiraigri, Ali H; Kassam, Aliya
2017-12-01
Hemoglobin E-beta thalassemia (Hb E/β-thalassemia) is a distinct, yet common, type of β-thalassemia, in which the patient co-inherits a β-thalassemia allele from one parent, and a structural variant, Hb E, from the other parent. This co-inheritance leads to remarkable clinical heterogeneity, varying degrees of chronic anemia, and a wide spectrum of complications due to ineffective erythropoiesis and iron overload. Hydroxyurea (HU), an oral chemotherapeutic drug, is expected to decrease disease severity. To assess the clinical efficacy and safety of HU in Hb E/β-thalassemia patients. We searched MEDLINE, EMBASE, Cochrane databases, and major preceding conferences for studies that assessed HU in Hb E/β-thalassemias patients. The effect size was estimated as a proportion (responder/sample size). Qualities of eligible studies were assessed using NIH tools. A total of five [one randomized clinical trial (RCT) and four observational] studies involving 106 patients were included. HU was associated with a significant RR of 46% with no statistical heterogeneity. No serious adverse effects were reported. Patients with Hb E/β-thalassemia may benefit from a trial of HU, though large RCTs assessing efficacy should be conducted to confirm the findings of this meta-analysis and to assess long-term toxicity and response sustainability.
A high-yield procedure for isolation of metaphase chromosomes from root tips of Vicia faba L.
Doležel, J; Cíhalíková, J; Lucretti, S
1992-08-01
A new method is described for the isolation of large quantities of Vicia faba metaphase chromosomes. Roots were treated with 2.5 mM hydroxyurea for 18 h to accumulate meristem tip cells at the G1/S interface. After release from the block, the cells re-entered the cell cycle with a high degree of synchrony. A treatment with 2.5 μM amiprophos-methyl (APM) was used to accumulate mitotic cells in metaphase. The highest metaphase index (53.9%) was achieved when, 6 h after the release from the hydroxyurea block, the roots were exposed to APM for 4 h. The chromosomes were released from formaldehyde-fixed root tips by chopping with a scalpel in LB01 lysis buffer. Both the quality and the quantity of isolated chromosomes, examined microscopically and by flow cytometry, depended on the extent of the fixation. The best results were achieved after fixation with 6% formaldehyde for 30 min. Under these conditions, 1 · 10(6) chromosomes were routinely obtained from 30 root tips. The chromosomes were morphologically intact and suitable both for high-resolution chromosome studies and for flow-cytometric analysis and sorting. After the addition of hexylene glycol, the chromosome suspensions could be stored at 4° C for six months without any signs of deterioration.
Winnicki, Konrad; Maszewski, Janusz
2012-11-01
Genotoxic stress caused by a variety of chemical and physical agents may lead to DNA breaks and genome instability. Response to DNA damage depends on ATM/ATR sensor kinases and their downstream proteins, which arrange cell cycle checkpoints. Activation of ATM (ataxia-telangiectasia-mutated)/ATR (ATM and Rad 3-related) signaling pathway triggers cell cycle arrest (by keeping cyclin-Cdk complexes inactive), combined with gamma-phosphorylation of histone H2A.X and induction of DNA repair processes. However, genotoxic stress activates also mitogen-activated protein kinases (MAPKs) which may control the functions of checkpoint proteins both directly, by post-translational modifications, or indirectly, by regulation of their expression. Our results indicate that in root meristem cells of Vicia faba, MAP kinase signaling pathway takes part in response to hydroxyurea-induced genotoxic stress. It is shown that SB202190, an inhibitor of p38 MAP kinase, triggers PCC (premature chromosome condensation) more rapidly, but only if cell cycle checkpoints are alleviated by caffeine. Since SB202190 and, independently, caffeine reduces HU-mediated histone H4 Lys5 acetylation, it may be that there is a cooperation of MAP kinase signaling pathways and ATM/ATR-dependent checkpoints during response to genotoxic stress. Copyright © 2012 Elsevier Masson SAS. All rights reserved.
A Phase I Study of Mebendazole for the Treatment of Pediatric Gliomas
2018-03-07
Pilomyxoid Astrocytoma; Pilocytic Astrocytoma; Glioma, Astrocytic; Optic Nerve Glioma; Pleomorphic Xanthoastrocytoma; Glioblastoma Multiforme; Anaplastic Astrocytoma; Gliosarcoma; Diffuse Intrinsic Pontine Glioma; DIPG; Low-grade Glioma; Brainstem Glioma
Togni Filho, Paulo Henrique; Casagrande, João Luiz Marin; Lederman, Henrique Manoel
2017-01-01
Objective To evaluate the utility of the inspiratory phase in high-resolution computed tomography (HRCT) of the chest for the diagnosis of post-bone marrow transplantation bronchiolitis obliterans. Materials and Methods This was a retrospective, observational, cross-sectional study. We selected patients of either gender who underwent bone marrow transplantation and chest HRCT between March 1, 2002 and December 12, 2014. Ages ranged from 3 months to 20.7 years. We included all examinations in which the HRCT was performed appropriately. The examinations were read by two radiologists, one with extensive experience in pediatric radiology and another in the third year of residency, who determined the presence or absence of the following imaging features: air trapping, bronchiectasis, alveolar opacities, nodules, and atelectasis. Results A total of 222 examinations were evaluated (mean, 5.4 ± 4.5 examinations per patient). The expiratory phase findings were comparable to those obtained in the inspiratory phase, except in one patient, in whom a small uncharacteristic nodule was identified only in the inspiratory phase. Air trapping was identified in a larger number of scans in the expiratory phase than in the inspiratory phase, as was atelectasis, although the difference was statistically significant only for air trapping. Conclusion In children being evaluated for post-bone marrow transplantation bronchiolitis obliterans, the inspiratory phase can be excluded from the chest HRCT protocol, thus reducing by half the radiation exposure in this population. PMID:28428651
Allen, Carl E; Laetsch, Theodore W; Mody, Rajen; Irwin, Meredith S; Lim, Megan S; Adamson, Peter C; Seibel, Nita L; Parsons, D Williams; Cho, Y Jae; Janeway, Katherine
2017-05-01
Over the past decades, outcomes for children with cancer have improved dramatically through serial clinical trials based in large measure on dose intensification of cytotoxic chemotherapy for children with high-risk malignancies. Progress made through such dose intensification, in general, is no longer yielding further improvements in outcome. With the revolution in sequencing technologies and rapid development of drugs that block specific proteins and pathways, there is now an opportunity to improve outcomes for pediatric cancer patients through mutation-based targeted therapeutic strategies. The Children's Oncology Group (COG), in partnership with the National Cancer Institute (NCI), is planning a trial entitled the COG-NCI Pediatric Molecular Analysis for Therapeutic Choice (Pediatric MATCH) protocol utilizing an umbrella design. This protocol will have centralized infrastructure and will consist of a biomarker profiling protocol and multiple single-arm phase II trials of targeted therapies. Pediatric patients with recurrent or refractory solid tumors, lymphomas, or histiocytoses with measurable disease will be eligible. The Pediatric MATCH Target and Agent Prioritization (TAP) committee includes membership representing COG disease committees, the Food and Drug Administration, and the NCI. The TAP Committee systematically reviewed target and agent pairs for inclusion in the Pediatric MATCH trial. Fifteen drug-target pairs were reviewed by the TAP Committee, with seven recommended for further development as initial arms of the Pediatric MATCH trial. The current evidence for availability, efficacy, and safety of targeted agents in children for each class of mutation considered for inclusion in the Pediatric MATCH trial is discussed in this review. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Trippett, Tanya M.; Herzog, Cynthia; Whitlock, James A.; Wolff, Johannes; Kuttesch, John; Bagatell, Rochelle; Hunger, Stephen P.; Boklan, Jessica; Smith, Amy A.; Arceci, Robert J.; Katzenstein, Howard M.; Harbison, Christopher; Zhou, Xiaofei; Lu, Haolan; Langer, Christiane; Weber, Martin; Gore, Lia
2009-01-01
Purpose To determine the dose of cetuximab that can be safely combined with irinotecan for treatment of pediatric and adolescent patients with refractory solid tumors. Patients and Methods This open-label, phase I study enrolled patients ages 1 to 18 years with advanced refractory solid tumors, including tumors of the CNS. Patient cohorts by age group (children, ages 1 to 12 years; adolescents, ages 13 to 18 years) received escalating weekly doses of cetuximab (75, 150, 250 mg/m2) in a 3 + 3 design, plus irinotecan (16 or 20 mg/m2/d) for 5 days for 2 consecutive weeks every 21 days. The primary end points were establishing the maximum-tolerated dose (MTD), recommended phase II dose (RPIID), and pharmacokinetics of the combination. Preliminary safety and efficacy data were also collected. Results Twenty-seven children and 19 adolescents received a median of 7.1 and 6.0 weeks of cetuximab therapy, respectively. Cetuximab 250 mg/m2 weekly plus irinotecan 16 mg/m2/d (pediatric) or 20 mg/m2/d (adolescent) have been established as the MTD/RPIID. Dose-limiting toxicities included diarrhea and neutropenia. Mild to moderate (grade 1 to 2) acneiform rash occurred in a majority of patients; no grade 3 to 4 rashes were observed. Cetuximab demonstrated dose-dependent clearance in both children and adolescents, similar to that in adults. There were two confirmed partial responses, both in patients with CNS tumors. Stable disease was achieved in 18 patients overall, including 10 patients with CNS tumors (38.5%). Conclusion The cetuximab/irinotecan combination can be given safely to children and adolescents with cancer. Promising activity, particularly in CNS tumors, warrants phase II evaluation of this regimen. PMID:19770383
Guidelines for Mass Screening of Congenital Hypothyroidism (2014 revision)
Nagasaki, Keisuke; Minamitani, Kanshi; Anzo, Makoto; Adachi, Masanori; Ishii, Tomohiro; Onigata, Kazumichi; Kusuda, Satoshi; Harada, Shohei; Horikawa, Reiko; Minagawa, Masanori; Mizuno, Haruo; Yamakami, Yuji; Fukushi, Masaru; Tajima, Toshihiro
2015-01-01
Purpose of developing the guidelines: Mass screening for congenital hypothyroidism started in 1979 in Japan, and the prognosis for intelligence has been improved by early diagnosis and treatment. The incidence was about 1/4000 of the birth population, but it has increased due to diagnosis of subclinical congenital hypothyroidism. The disease requires continuous treatment, and specialized medical facilities should make a differential diagnosis and treat subjects who are positive in mass screening to avoid unnecessary treatment. The Guidelines for Mass Screening of Congenital Hypothyroidism (1998 version) were developed by the Mass Screening Committee of the Japanese Society for Pediatric Endocrinology in 1998. Subsequently, new findings on prognosis and problems in the adult phase have emerged. Based on these new findings, the 1998 guidelines were revised in the current document (hereinafter referred to as the Guidelines). Target disease/conditions: Primary congenital hypothyroidism. Users of the Guidelines: Physician specialists in pediatric endocrinology, pediatric specialists, physicians referring patients to pediatric practitioners, general physicians, laboratory technicians in charge of mass screening, and patients. PMID:26594093
Pindrik, Jonathan; Hoang, Nguyen; Tubbs, R Shane; Rocque, Brandon J; Rozzelle, Curtis J
2017-08-01
Phase II monitoring with intracranial electroencephalography (ICEEG) occasionally requires bilateral placement of subdural (SD) strips, grids, and/or depth electrodes. While phase I monitoring often demonstrates a preponderance of unilateral findings, individual studies (video EEG, single photon emission computed tomography [SPECT], and positron emission tomography [PET]) can suggest or fail to exclude a contralateral epileptogenic onset zone. This study describes previously unreported techniques of trans-falcine and sub-frontal insertion of contralateral SD grids and depth electrodes for phase II monitoring in pediatric epilepsy surgery patients when concern about bilateral abnormalities has been elicited during phase I monitoring. Pediatric patients with medically refractory epilepsy undergoing stage I surgery for phase II monitoring involving sub-frontal and/or trans-falcine insertion of SD grids and/or depth electrodes at the senior author's institution were retrospectively reviewed. Intra-operative technical details of sub-frontal and trans-falcine approaches were studied, while intra-operative complications or events were noted. Operative techniques included gentle subfrontal retraction and elevation of the olfactory tracts (while preserving the relationship between the olfactory bulb and cribriform plate) to insert SD grids across the midline for coverage of the contralateral orbito-frontal regions. Trans-falcine approaches involved accessing the inter-hemispheric space, bipolar cauterization of the anterior falx cerebri below the superior sagittal sinus, and sharp dissection using a blunt elevator and small blade scalpel. The falcine window allowed contralateral SD strip, grid, and depth electrodes to be inserted for coverage of the contralateral frontal regions. The study cohort included seven patients undergoing sub-frontal and/or trans-falcine insertion of contralateral SD strip, grid, and/or depth electrodes from February 2012 through June 2015. Five patients (71%) experienced no intra-operative events related to contralateral ICEEG electrode insertion. Intra-operative events of frontal territory venous engorgement (1/7, 14%) due to sacrifice of anterior bridging veins draining into the SSS and avulsion of a contralateral bridging vein (1/7, 14%), probably due to prior anterior corpus callosotomy, each occurred in one patient. There were no intra-operative or peri-operative complications in any of the patients studied. Two patients required additional surgery for supplemental SD strip and/or depth electrodes via burr hole craniectomy to enhance phase II monitoring. All patients proceeded to stage II surgery for resection of ipsilateral epileptogenic onset zones without adverse events. Trans-falcine and sub-frontal insertion of contralateral SD strip, grid, and depth electrodes are previously unreported techniques for achieving bilateral frontal coverage in phase II monitoring in pediatric epilepsy surgery. This technique obviates the need for contralateral craniotomy and parenchymal exposure with limited, remediable risks. Larger case series using the method described herein are now necessary.
Department of Clinical Investigation Annual Research Progress Report, Fiscal Year 1984. Volume 2,
1984-10-01
Brooke Army Medical Center Dept/Svc Associate Investigators: Department of Pediatrics Key Words: Ewing ’s sarcoma Accumulative MEDCASE Eat Accumulative...Modality Therapy for Disseminated Soft Tissue 289 Sarcomas , Phase III. (0) SWOG 8025 Combination Chemotherapy for Chronic Lymphocytic Leukemia. 290 *(C...Metastatic Islet Cell 318 Carcinoma, Phase I1. (0) SWOG 8209 A Study of AZQ in Soft Tissue and Bony Sarcomas , Phase 1I. 319 (C) SWOG 8210 A Comparison
Brown, Patrick; Megason, Gail; Ahn, Hyo Seop; Cho, Bin; Kirov, Ivan; Frankel, Lawrence; Aplenc, Richard; Bensen-Kennedy, Debra; Munteanu, Mihaela; Weaver, Jennifer; Harker-Murray, Paul
2014-01-01
This open-label, single-arm, phase I/II, dose-escalation study was designed to determine the recommended phase II dose (RP2D), pharmacokinetics, tolerability, and efficacy of bendamustine in pediatric patients (age ranging from 1 to 20 y) with histologically proven relapsed/refractory acute lymphoblastic leukemia (ALL) or acute myeloid leukemia (AML). Patients (27 with ALL, 16 with AML) received intravenous bendamustine on days 1 and 2 of each treatment cycle. Phase I involved planned dose escalation of bendamustine to establish the RP2D for phase II. Objectives included overall response rate, duration of response, and tolerability. Eleven patients were treated in phase I, and the RP2D was 120 mg/m2. In phase II, 32 patients received bendamustine 120 mg/m2. Two patients with ALL (bendamustine 90 mg/m2) experienced complete response (CR). Among patients who received bendamustine 120 mg/m2, 2 experienced partial response (PR); 7 had stable disease. The overall response rate (CR+CR without platelet recovery [CRp]) was 4.7% and biological activity rate (CR+CRp+PR) was 9.3%. No AML patients responded. The most common adverse events were anemia, neutropenia, thrombocytopenia, pyrexia, nausea, vomiting, and diarrhea. Bendamustine monotherapy has acceptable tolerability in heavily pretreated children with relapsed/refractory ALL or AML and appears to have some activity in ALL, warranting further studies in combination trials. PMID:24072240
Moler, Frank W; Silverstein, Faye S; Meert, Kathleen L; Clark, Amy E; Holubkov, Richard; Browning, Brittan; Slomine, Beth S; Christensen, James R; Dean, J Michael
2013-09-01
To describe the rationale, timeline, study design, and protocol overview of the Therapeutic Hypothermia after Pediatric Cardiac Arrest trials. Multicenter randomized controlled trials. Pediatric intensive care and cardiac ICUs in the United States and Canada. Children from 48 hours to 18 years old, who have return of circulation after cardiac arrest, who meet trial eligibility criteria, and whose guardians provide written consent. Therapeutic hypothermia or therapeutic normothermia. From concept inception in 2002 until trial initiation in 2009, 7 years were required to plan and operationalize the Therapeutic Hypothermia after Pediatric Cardiac Arrest trials. Two National Institute of Child Health and Human Development clinical trial planning grants (R21 and R34) supported feasibility assessment and protocol development. Two clinical research networks, Pediatric Emergency Care Applied Research Network and Collaborative Pediatric Critical Care Research Network, provided infrastructure resources. Two National Heart Lung Blood Institute U01 awards provided funding to conduct separate trials of in-hospital and out-of-hospital cardiac arrest. A pilot vanguard phase that included half the clinical sites began on March 9, 2009, and this was followed by full trial funding through 2015. Over a decade will have been required to plan, design, operationalize, and conduct the Therapeutic Hypothermia after Pediatric Cardiac Arrest trials. Details described in this report, such as participation of clinical research networks and clinical trial planning grants utilization, may be of utility for individuals who are planning investigator-initiated, federally supported clinical trials.
Kanter, Robert K
2012-09-01
To empirically describe the integration of pediatric disaster services into regional systems of care after the April 27, 2011, tornado in Tuscaloosa, Alabama, a community with no pediatric emergency department or pediatric intensive care unit and few pediatric subspecialists. Data were obtained in interviews with key informants including professional staff and managers from public health and emergency management agencies, prehospital emergency medical services, fire departments, hospital nurses, physicians, and the trauma program coordinator. A single hospital in Tuscaloosa served 800 patients on the night of the tornado. More than 100 of these patients were children, including more than 20 with critical injuries. Many children were unaccompanied and unidentified on arrival. Resuscitation and stabilization were performed by nonpediatric prehospital and emergency department staff. More than 20 children were secondarily transported to the nearest children's hospital an hour's drive away under the care of nonpediatric local emergency medical services providers. No preventable adverse events were identified in the resuscitation and secondary transport phases of care. Stockpiled supplies and equipment were adequate to serve the needs of the disaster victims, including the children. Essential aspects of preparation include pediatric-specific clinical skills, supplies and equipment, operational disaster plans, and interagency practice embedded in everyday work. Opportunities for improvement identified include more timely response to warnings, improved practices for identifying unaccompanied children, and enhanced child safety in shelters. Successful responses depended on integration of pediatric services into regional systems of care. Copyright © 2012 Mosby, Inc. All rights reserved.
The pediatric mandible: II. Management of traumatic injury or fracture.
Smartt, James M; Low, David W; Bartlett, Scott P
2005-08-01
After studying this article, the participant should be able to: 1. Describe the changing epidemiology of mandibular fractures in children and adolescents. 2. Discuss the appropriate use of internal fixation in the treatment of pediatric mandibular fractures. 3. Describe the difficulties posed by the deciduous dentition in the use of interdental wiring. 4. Understand reasons why techniques specific to adult fractures may not be applicable to the growing mandible. 5. Understand the etiology and epidemiology of pediatric mandibular fractures. 6. Understand the reasons for conservative (closed) versus aggressive (open) treatment of mandibular injury. Fractures of the pediatric mandible are complicated by the anatomic complexity of the developing mandible, particularly by the presence of tooth buds and the eruption of deciduous and permanent teeth. Traditional methods of fracture reduction and fixation employed in adults have little applicability in the pediatric population. The authors describe the surgical techniques that have been used at their institution and those that can be used safely in the pediatric setting. In most cases, "conservative" management is the preferred option, especially in the treatment of condylar fractures. In cases requiring surgical intervention, interdental wiring, drop wires in combination with circummandibular wires, and acrylic splints are suited well to specific phases of dental maturation. Open reduction and internal fixation using monocortical screws and microplates or resorbable plates and screws are acceptable techniques in the pediatric patient, but they require special safeguards. Algorithms are presented to simplify management of these complicated injuries.
Aloni, Michel Ntetani; Nkee, Leonard
2014-01-01
In the Democratic Republic of Congo (DRC), sickle cell disease is not yet really regarded as a health care priority. The patterns of sickle cell disease in patients living in Kinshasa, DRC are discussed and the difficulties encountered in their management are highlighted. The cross-sectional survey is of sickle cell patients and their families attending the Centre de Médecine Mixte et d'Anémie SS de Yolo (CMMASS), Kinshasa, DRC, between January and April 2009. Completed questionnaires were received from 168 respondents (111 girls; 57 boys). Seventy-one percent of the subjects were diagnosed before the age of 2 years but none in the neonatal period. Sickle cell disease was diagnosed in 54.8% of the patients after they had suffered pain crises. Of the 168 subjects, 74.0% had previously received blood transfusions. Seventy-five (45.0%) had more than three severe pain crises per year. A minority of 35.0% reported that they regularly took an antibioprophylaxis. Seventy-five (45.0%) subjects were eligible for hydroxyurea (HU) therapy but in all cases this drug was taken irregularly. Eighty-two percent of drugs were purchased by the parents. One hundred and sixty-three children (97.0%) were vaccinated according to the Expanded Programme on Immunization (EPI), 61.0% against Streptococcus pneumoniae and 16.0% against the Hepatitis B virus (HBV). No case of immunization against Hemophilus influenzae and Salmonella sp was reported. Neonatal screening programs, early educational detection programs for families, use of current method treatments and an implementation of a health insurance system for sickle cell disease will improve detection and management for these and future patients in our population.
[Sickle cell anemia: experience in a center].
Gómez-Chiari, M; Tusell Puigbert, J; Ortega Aramburu, J
2003-02-01
Sickle cell anemia is a structural hemoglobinopathy in which morphological and physical changes in erythrocytes cause vaso-occlusive episodes in various organs and tissues. The disease is common among blacks and the African population. As a result of the growing migratory flow, this is an emerging disease in Spain. To present the casuistics of a pediatric hospital: clinical onset, the most frequent features and complications, and treatment. We performed a retrospective study of 22 patients aged less than 18 years old diagnosed with sickle cell anemia between January 1985 and December 2001. Epidemiologic data, symptoms, complications, blood test results, treatment, and response were recorded. The mean age of the patients was 39 months. In 54 %, diagnosis was established before the age of 2 years. No differences were found in sex. The countries of origin were Gambia in 32 %, Morocco in 23 %, and Senegal in 18 % as well as other African and Central America countries; 53 % of the children were born in Spain. The most common complaint was vaso-occlusive pain localized in the abdomen (45 %). The most frequent complications were infections and 13.7 % suffered stroke. Twenty-eight percent of the patients diagnosed before the age of 2 years presented complications. Eleven patients received hydroxyurea for recurrent vaso-occlusive crises with favorable results; one patient underwent splenectomy and another received an allogenic bone marrow transplant from an HLA-identical brother with excellent results. This study reproduces the data described in the literature from countries with a high prevalence of the disease. Morbidity could be minimized by early diagnosis and preventive treatment and good healthcare. Given the increasing incidence of the disease, screening of black and African neonates and genetic counseling are recommended together with guidelines for prompt and appropriate treatment in primary health centers and emergency departments.
Characterization of opioid use in sickle cell disease.
Han, Jin; Zhou, Jifang; Saraf, Santosh L; Gordeuk, Victor R; Calip, Gregory S
2018-05-01
Opioid analgesics are commonly used to treat vaso-occlusive pain episodes in sickle cell disease (SCD), but comprehensive evidence characterizing opioid use in this patient population is limited. Our objective was to characterize opioid use patterns among SCD patients using a large nationwide database. A large, US medical claims database was utilized to identify a cohort of 3882 SCD patients, and characteristics of opioid use were analyzed. Clinical variables including age, gender, medication use, health care utilization, and medical history were evaluated for correlations with opioid use. Forty percent of patients took opioid medications during a 12-month span, and the prevalence of any opioid use was highest for 20 to 29-year-old patients (58%). The median daily opioid dose was 1.85 mg (interquartile range: 0.62-10.68 mg) oral morphine equivalents (OME). While most opioid users took between 0 and 5 mg OME daily, 3% of pediatric patients and 23% of adult patients used more than 30-mg OME daily. High-dose opioid use was associated with older age, hydroxyurea therapy, nonsteroidal anti-inflammatory drug (NSAID) use, and frequent inpatient hospitalizations. In multivariable-adjusted analyses, patients with vaso-occlusive complications such as pain crisis (OR = 3.8, 95% CI 2.7-5.3) and avascular necrosis (AVN) (OR = 3.7, 95% CI 2.7-5.1) were associated with high-dose opioid use. Our study showed that only 40% SCD patients were on opioid analgesics during a 12-month span. However, a non-trivial number of patients used a much higher dose of opioids despite a relatively low average daily opioid dose among SCD patients, particularly with vaso-occlusive complications. Copyright © 2017 John Wiley & Sons, Ltd.
Musso, Loana; Cincinelli, Raffaella; Zuco, Valentina; Zunino, Franco; Nurisso, Alessandra; Cuendet, Muriel; Giannini, Giuseppe; Vesci, Loredana; Pisano, Claudio; Dallavalle, Sabrina
2015-10-15
A series of alternative Zn-binding groups were explored in the design of phenyl-4-yl-acrylohydroxamic acid derivatives as histone deacetylase (HDAC) inhibitors. Most of the synthesized compounds were less effective than the parent hydroxamic acid. However, the profile of activity shown by the analog bearing a hydroxyurea head group, makes this derivative promising for further investigation. Copyright © 2015 Elsevier Ltd. All rights reserved.
Partnering with parents in a pediatric ambulatory care setting: a new model.
Tourigny, Jocelyne; Chartrand, Julie
2015-06-01
Pediatric care has greatly evolved during the past 30 years, moving from a traditional, medically oriented approach to a more consultative, interactive model. In the literature, the concept of partnership has been explored and presented in various terms, including presence, collaboration, involvement, and participation. The models of partnership that have been proposed have rarely been evaluated, and do not take the unique environment of ambulatory care into account. Based on a literature review, strong clinical experience with families, and previous research with parents and health professionals, both the conceptual and empirical phases of a new model are described. This model can be adapted to other pediatric health care contexts in either primary or tertiary care and should be evaluated in terms of efficacy and usefulness.
Price, Julia; Kassam-Adams, Nancy; Alderfer, Melissa A; Christofferson, Jennifer; Kazak, Anne E
2016-01-01
The objective of this systematic review is to reevaluate and update the Integrative Model of Pediatric Medical Traumatic Stress (PMTS; Kazak et al., 2006), which provides a conceptual framework for traumatic stress responses across pediatric illnesses and injuries. Using established systematic review guidelines, we searched PsycINFO, Cumulative Index to Nursing and Allied Health Literature, and PubMed (producing 216 PMTS papers published since 2005), extracted findings for review, and organized and interpreted findings within the Integrative Model framework. Recent PMTS research has included additional pediatric populations, used advanced longitudinal modeling techniques, clarified relations between parent and child PMTS, and considered effects of PMTS on health outcomes. Results support and extend the model's five assumptions, and suggest a sixth assumption related to health outcomes and PMTS. Based on new evidence, the renamed Integrative Trajectory Model includes phases corresponding with medical events, adds family-centered trajectories, reaffirms a competency-based framework, and suggests updated assessment and intervention implications. © The Author 2015. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Fehr, Folkert; Weiß-Becker, Christoph; Becker, Hera; Opladen, Thomas
2017-01-01
There is an absence of broad-based and binding curricular requirements for structured competency-based post-graduate medical training in Germany, and thus no basis for comparing the competencies of physicians undergoing training in a medical specialty ( Ärzte im Weiterbildung ). In response, the German Society of Primary Care Pediatrics' working group on post-graduate education (DGAAP) has identified realistic entrustable professional activities (EPAs) in primary care, defined their number, scope and content, selected competency domains, specified required knowledge and skills, and described appropriate assessment methods. These guidelines are referred to as PaedCompenda and can be accessed electronically by educators in pediatric medicine; the use and effectiveness of these guidelines are monitored by the German Association for Medical Education's committee on post-graduate education (GMA). Teaching and training in pediatric medicine should take EPAs into consideration. To accomplish this, phases dedicated to primary care should be integrated into formal medical specialty training. Primary care pediatrics must enhance the sites where such training takes place into learning environments that prepare physicians trainees and turn the practicing specialists into mentoring educators.
Pediatrics Milestone Project: Next Steps Toward Meaningful Outcomes Assessment
Hicks, Patricia J.; Englander, Robert; Schumacher, Daniel J.; Burke, Ann; Benson, Bradley J.; Guralnick, Susan; Ludwig, Stephen; Carraccio, Carol
2010-01-01
In the September 2010 issue of JGME, the Pediatric Milestones Working Group published “The Pediatrics Milestones: Conceptual Framework, Guiding Principles, and Approach to Development”, a document that describes the construction of the first iteration of the Pediatric Milestones. These Milestones were developed by the Working Group as a group of practical behavioral expectations for each of the 52 sub-competencies. In constructing these Milestones, the authors were cognizant of the need to ground the Milestones themselves in evidence, theories or other conceptual frameworks that would provide the basis for the ontogeny of development for each sub-competency. During this next phase of the Milestones development, the process will continue with consultation with content experts and consideration of assessment of Milestones. We have described possible measurement tools, explored threats to validity, establishment of benchmarks, and possible approaches to reporting of performance. The vision of the Pediatrics Milestone Project is to understand the development of a pediatrician from entry into medical school through the twilight of a physician’s career, and the work will require a collaborative effort of the undergraduate and graduate medical education communities, and the accrediting and certifying bodies. PMID:22132281
Phoenix, Michelle; Rosenbaum, Peter; Watson, Denise; Camden, Chantal
2016-01-01
Pediatric rehabilitation centers constantly reorganize services to accommodate changes in funding, client needs, evidence-based practices, accountability requirements, theoretical models, and values. However, there are few service delivery models or descriptions of how organizations plan for change to guide organizations through this complex task. This case report presents the "5Rs of Reorganization," a novel process for planning service delivery reorganization projects in pediatric rehabilitation centers. The 5Rs include: 1. Recognize the need for change, 2. Reallocate resources for project management, 3. Review the reality of clients, service delivery, and the community, 4. Reconstruct reality, and 5. Report results. The implementation and outcomes of the "5Rs of Reorganization" process are described for one pediatric rehabilitation center to illustrate how use of this process led to effective service delivery reorganization planning. The resulting multi-component customized service delivery plan reflects high levels of stakeholder involvement. Principles of project management can be applied to support service delivery reorganization planning within pediatric rehabilitation centers using the "5Rs of Reorganization." Strong communication throughout the planning phase is key to developing and sharing a plan for service delivery reorganization. Communication can be supported through use of the 5R process.
Goldman, Stewart; Yamada, Tohru; Beattie, Craig W.; Bressler, Linda; Pacini, Michael; Pollack, Ian F.; Fisher, Paul Graham; Packer, Roger J.; Dunkel, Ira J.; Dhall, Girish; Wu, Shengjie; Onar, Arzu; Boyett, James M.; Fouladi, Maryam
2016-01-01
Background p53 is a promising target in human cancer. p28 is a cell-penetrating peptide that preferentially enters cancer cells and binds to both wild-type and mutant p53 protein, inhibiting COP1-mediated ubiquitination and proteasomal degradation. This results in increased levels of p53, which induces cell cycle arrest at G2/M. We conducted a phase I study to determine the maximum-tolerated dose (MTD) and describe the dose-limiting toxicities (DLTs) and pharmacokinetics (PKs) of p28 in children. Methods Children aged 3–21 years with recurrent or progressive central nervous system tumors were eligible. Intravenous p28 was administered 3 times weekly for 4 consecutive weeks of a 6-week cycle at 4.16 mg/kg/dose (the adult recommended phase II dose) using a rolling-6 study design. Expression status of p53 was characterized by immunohistochemistry, and serum PK parameters were established on the second dose. Results Of the 18 eligible patients enrolled in the study, 12 completed the DLT monitoring period and were evaluable for toxicity. p28 was well-tolerated; 7 participants received ≥2 courses, and the most common adverse event attributed to the drug was transient grade 1 infusion-related reaction. PK analysis revealed a profile similar to adults; however, an increased area under the curve was observed in pediatric patients. High p53 expression in tumor cell nuclei was observed in 6 of 12 available tissue samples. There were no objective responses; 2 participants remained stable on the study for >4 cycles. Conclusions This phase I study demonstrated that p28 is well-tolerated in children with recurrent CNS malignancies at the adult recommended phase II dose. PMID:27022131
Prognosis for children with acute liver failure due to Amanita phalloides poisoning
NASA Astrophysics Data System (ADS)
Wachulski, Marcin F.; Kamińska-Gocał, Diana; Dądalski, Maciej; Socha, Piotr; Mulawka, Jan J.
2011-10-01
The primary objective of this article is to find new effective methods of diagnosis of urgent liver transplantation after Amanita phalloides intoxication amongst pediatric patients. The research was carried out using a medical database of pediatric patients who suffered from acute liver failure after amatoxin consumption. After data preprocessing and attribute selection steps, a two-phase experiment was conducted, which incorporated a wide variety of data mining algorithms. The results deliver two equivalent classification models with simple decision structure and reasonable quality of surgery prediction.
Da Silveira, Rita De Cássia Viveiros; Da Silva, Marcelo Santos; Nunes, Vinícius Santana; Perez, Arina Marina; Cano, Maria Isabel Nogueira
2013-04-01
We have previously shown that the subunit 1 of Leishmania amazonensis RPA (LaRPA-1) alone binds the G-rich telomeric strand and is structurally different from other RPA-1. It is analogous to telomere end-binding proteins described in model eukaryotes whose homologues were not identified in the protozoan´s genome. Here we show that LaRPA-1 is involved with damage response and telomere protection although it lacks the RPA1N domain involved with the binding with multiple checkpoint proteins. We induced DNA double-strand breaks (DSBs) in Leishmania using phleomycin. Damage was confirmed by TUNEL-positive nuclei and triggered a G1/S cell cycle arrest that was accompanied by nuclear accumulation of LaRPA-1 and RAD51 in the S phase of hydroxyurea-synchronized parasites. DSBs also increased the levels of RAD51 in non-synchronized parasites and of LaRPA-1 and RAD51 in the S phase of synchronized cells. More LaRPA-1 appeared immunoprecipitating telomeres in vivo and associated in a complex containing RAD51, although this interaction needs more investigation. RAD51 apparently co-localized with few telomeric clusters but it did not immunoprecipitate telomeric DNA. These findings suggest that LaRPA-1 and RAD51 work together in response to DNA DSBs and at telomeres, upon damage, LaRPA-1 works probably to prevent loss of single-stranded DNA and to assume a capping function.
POB3 is required for both transcription and replication in the yeast Saccharomyces cerevisiae.
Schlesinger, M B; Formosa, T
2000-01-01
Spt16 and Pob3 form stable heterodimers in Saccharomyces cerevisiae, and homologous proteins have also been purified as complexes from diverse eukaryotes. This conserved factor has been implicated in both transcription and replication and may affect both by altering the characteristics of chromatin. Here we describe the isolation and properties of a set of pob3 mutants and confirm that they have defects in both replication and transcription. Mutation of POB3 caused the Spt(-) phenotype, spt16 and pob3 alleles displayed severe synthetic defects, and elevated levels of Pob3 suppressed some spt16 phenotypes. These results are consistent with previous reports that Spt16 and Pob3 act in a complex that modulates transcription. Additional genetic interactions were observed between pob3 mutations and the genes encoding several DNA replication factors, including POL1, CTF4, DNA2, and CHL12. pob3 alleles caused sensitivity to the ribonucleotide reductase inhibitor hydroxyurea, indicating a defect in a process requiring rapid dNTP synthesis. Mutation of the S phase checkpoint gene MEC1 caused pob3 mutants to lose viability rapidly under restrictive conditions, revealing defects in a process monitored by Mec1. Direct examination of DNA contents by flow cytometry showed that S phase onset and progression were delayed when POB3 was mutated. We conclude that Pob3 is required for normal replication as well as for transcription. PMID:10924459
Post-Acute Effectiveness of Lithium in Pediatric Bipolar I Disorder
Kafantaris, Vivian; Pavuluri, Mani; McNamara, Nora K; Frazier, Jean A; Sikich, Linmarie; Kowatch, Robert; Rowles, Brieana M; Clemons, Traci E; Taylor-Zapata, Perdita
2013-01-01
Abstract Objective This study examined the long-term effectiveness of lithium for the treatment of pediatric bipolar disorder within the context of combination mood stabilizer therapy for refractory mania and pharmacological treatment of comorbid psychiatric conditions. Methods Outpatients, ages 7–17 years, meeting American Psychiatric Association, Diagnostic and Statistical Manual of Mental Disorders, 4th ed. (DSM-IV) diagnostic criteria for bipolar disorder I (BP-I) (manic or mixed) who demonstrated at least a partial response to 8 weeks of open-label treatment with lithium (Phase I) were eligible to receive open-label lithium for an additional 16 weeks (Phase II). Up to two adjunctive medications could be prescribed to patients experiencing residual symptoms of mania or comorbid psychiatric conditions, following a standardized algorithm. Results Forty-one patients received continued open-label long-term treatment with lithium for a mean of 14.9 (3.0) weeks during Phase II. The mean weight-adjusted total daily dose at end of Phase II was 27.8 (6.7) mg/kg/day, with an average lithium concentration of 1.0 (0.3) mEq/L. Twenty-five of the 41 patients (60.9%) were prescribed adjunctive psychotropic medications for residual symptoms. The most frequent indications for adjunctive medications were refractory mania (n=13; 31.7%) and attention-deficit/hyperactivity disorder (ADHD) (n=15; 36.6%). At the end of this phase 28 (68.3%) patients met a priori criteria for response (≥50% reduction from Phase I baseline in Young Mania Rating Scale [YMRS] summary score and a Clinical Global Impressions-Improvement [CGI-I] score of 1 or 2), with 22 (53.7%) considered to be in remission (YMRS summary score≤12 and CGI-Severity score of 1 or 2). These data suggest that patients who initially responded to lithium maintained mood stabilization during continuation treatment, but partial responders did not experience further improvement during Phase II, despite the opportunity to receive adjunctive medications. The most commonly reported (≥20%) adverse events associated with lithium treatment were vomiting, headache, abdominal pain, and tremor. Conclusions Lithium may be a safe and effective longer-term treatment for patients with pediatric bipolar disorder who respond to acute treatment with lithium. Partial responders to acute lithium did not appear to experience substantial symptom improvement during the continuation phase, despite the possibility that adjunctive medications could be prescribed. PMID:23510444
Hu, Zhubing; Cools, Toon; Kalhorzadeh, Pooneh; Heyman, Jefri; De Veylder, Lieven
2015-01-01
To maintain genome integrity, DNA replication is executed and regulated by a complex molecular network of numerous proteins, including helicases and cell cycle checkpoint regulators. Through a systematic screening for putative replication mutants, we identified an Arabidopsis thaliana homolog of human Regulator of Telomere Length 1 (RTEL1), which functions in DNA replication, DNA repair, and recombination. RTEL1 deficiency retards plant growth, a phenotype including a prolonged S-phase duration and decreased cell proliferation. Genetic analysis revealed that rtel1 mutant plants show activated cell cycle checkpoints, specific sensitivity to DNA cross-linking agents, and increased homologous recombination, but a lack of progressive shortening of telomeres, indicating that RTEL1 functions have only been partially conserved between mammals and plants. Surprisingly, RTEL1 deficiency induces tolerance to the deoxynucleotide-depleting drug hydroxyurea, which could be mimicked by DNA cross-linking agents. This resistance does not rely on the essential replication checkpoint regulator WEE1 but could be blocked by a mutation in the SOG1 transcription factor. Taken together, our data indicate that RTEL1 is required for DNA replication and that its deficiency activates a SOG1-dependent replication checkpoint. PMID:25595823
Awoda, Shiekh; Daak, Ahmed A; Husain, Nazik Elmalaika; Ghebremeskel, Kebreab; Elbashir, Mustafa I
2017-01-01
It has been reported that patients with SCD do have an abnormal coagulation profile. Coagulopathy is thought to be one of the key factors that contribute to the vaso-occlusive crisis that characterises sickle cell disease (SCD). In this study, we investigated whether Sudanese sickle cell patients have an abnormal coagulation profile. In addition, the effect of treatment with either omega-3 fatty acids or hydroxyurea on coagulation profile was assessed. Homozygous SCD patients untreated ( n = 52), omega-3 treated ( n = 44), hydroxyurea (HU) treated ( n = 8) and healthy (HbAA) controls ( n = 52) matched for age (4-20 years), gender and socioeconomic status were enrolled. Patients on omega-3 fatty acids, according to age, received one to four capsules containing 277.8 mg DHA and 39.0 mg eicosapentnoic. Patients on Hydroxyurea were in on dosage more than 20 mg/kg/day. The steady state levels of the coagulation parameters and the effect of the treatments with either HU or omega-3 fatty acids on markers of coagulation were investigated. Compared to the healthy controls, treated and untreated HbSS patients had lower hemoglobin, plasma Protein C, proteins S and higher white blood cell count (WBC), platelets count (PLTs) and plasma D-dimer levels,( p < 0.05). In comparison to untreated HbSS, treatment with neither omega-3 nor HU had effect on the WBC, plasma proteins C and S, ( p > 0.05). HU treated group had a lower PLTs count compared to HbSS untreated group ( p < 0.5). The prothrombin and activated partial thromboplastin times and international normalized ratio (INR) of untreated patients are significantly higher than n-3 treated, HU-treated patients and health controls, ( p < 0.05). Patients treated with omega-3 had lowered D-dimer levels in comparison to HU-treated and untreated HbSS patients, ( p < 0.001). This study provides evidence that Sudanes patients have abnormal coagulation profile and treatment with either HU or omega-3 fatty acids might partially ameliorate SCD-associated chronic coagulopathic state.
Tanaka, Jun; Kasai, Hidefumi; Shimizu, Kenji; Shimasaki, Shigeki; Kumagai, Yuji
2013-03-01
We performed a population pharmacokinetic analysis of phenytoin after intravenous administration of fosphenytoin sodium in healthy, neurosurgical, and epileptic subjects, including pediatric patients, and determined the optimal dose and infusion rate for achieving the therapeutic range. We used pooled data obtained from two phase I studies and one phase III study performed in Japan. The population pharmacokinetic analysis was performed using NONMEM software. The optimal dose and infusion rate were determined using simulation results obtained using the final model. The therapeutic range for total plasma phenytoin concentration is 10-20 μg/mL. We used a linear two-compartment model with conversion of fosphenytoin to phenytoin. Pharmacokinetic parameters of phenytoin, such as total clearance and central and peripheral volume of distribution were influenced by body weight. The dose simulations are as follows. In adult patients, the optimal dose and infusion rate of phenytoin for achieving the therapeutic range was 22.5 mg/kg and 3 mg/kg/min respectively. In pediatric patients, the total plasma concentration of phenytoin was within the therapeutic range for a shorter duration than that in adult patients at 22.5 mg/kg (3 mg/kg/min). However, many pediatric patients showed phenytoin concentration within the toxic range after administration of a dose of 30 mg/kg. The pharmacokinetics of phenytoin after intravenous administration of fosphenytoin sodium could be described using a linear two-compartment model. The administration of fosphenytoin sodium 22.5 mg/kg at an infusion rate of 3 mg/kg/min was optimal for achieving the desired plasma phenytoin concentration.
Mesa, Ruben; Verstovsek, Srdan; Kiladjian, Jean-Jacques; Griesshammer, Martin; Masszi, Tamas; Durrant, Simon; Passamonti, Francesco; Harrison, Claire N; Pane, Fabrizio; Zachee, Pierre; Zhen, Huiling; Jones, Mark M; Parasuraman, Shreekant; Li, Jingjin; Côté, Isabelle; Habr, Dany; Vannucchi, Alessandro M
2016-08-01
Polycythemia vera (PV)-related symptoms may not be adequately controlled with conventional therapy. This current analysis of the RESPONSE trial evaluated the effects of ruxolitinib compared with standard therapy on quality of life (QoL) and symptoms in patients with PV who were hydroxyurea resistant/intolerant. In the previously reported primary analysis, ruxolitinib achieved the primary composite endpoint of hematocrit control and ≥35% reduction in spleen volume at Week 32. The current analysis evaluated patient-reported outcomes using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30), the Myeloproliferative Neoplasm Symptom Assessment Form (MPN-SAF), the Pruritus Symptom Impact Scale (PSIS), and the Patient Global Impression of Change (PGIC). Compared with standard therapy, ruxolitinib was associated with greater improvements in global health status/QoL, functional subscales, and individual symptom scores of the EORTC QLQ-C30. At Week 32, more patients in the ruxolitinib arm (44%) achieved a ≥10-point improvement in global health status/QoL vs. standard therapy (9%). Improvements in MPN-SAF symptom scores were consistent with improvements in EORTC QLQ-C30, PSIS, and PGIC scores. Ruxolitinib provides clinically relevant improvements in QoL and ameliorates symptom burden in patients with PV who are hydroxyurea resistant/intolerant. © 2016 The Authors. European Journal of Haematology Published by John Wiley & Sons Ltd.
Davis, L; Barbera, M; McDonnell, A; McIntyre, K; Sternglanz, R; Jin , Q; Loidl, J; Engebrecht, J
2001-01-01
The Saccharomyces cerevisiae MUM2 gene is essential for meiotic, but not mitotic, DNA replication and thus sporulation. Genetic interactions between MUM2 and a component of the origin recognition complex and polymerase alpha-primase suggest that MUM2 influences the function of the DNA replication machinery. Early meiotic gene expression is induced to a much greater extent in mum2 cells than in meiotic cells treated with the DNA synthesis inhibitor hydroxyurea. This result indicates that the mum2 meiotic arrest is downstream of the arrest induced by hydroxyurea and suggests that DNA synthesis is initiated in the mutant. Genetic analyses indicate that the recombination that occurs in mum2 mutants is dependent on the normal recombination machinery and on synaptonemal complex components and therefore is not a consequence of lesions created by incompletely replicated DNA. Both meiotic ectopic and allelic recombination are similarly reduced in the mum2 mutant, and the levels are consistent with the levels of meiosis-specific DSBs that are generated. Cytological analyses of mum2 mutants show that chromosome pairing and synapsis occur, although at reduced levels compared to wild type. Given the near-wild-type levels of meiotic gene expression, pairing, and synapsis, we suggest that the reduction in DNA replication is directly responsible for the reduced level of DSBs and meiotic recombination. PMID:11238403
Kubovcakova, Lucia; Lundberg, Pontus; Grisouard, Jean; Hao-Shen, Hui; Romanet, Vincent; Andraos, Rita; Murakami, Masato; Dirnhofer, Stephan; Wagner, Kay-Uwe; Radimerski, Thomas; Skoda, Radek C
2013-02-14
To establish a preclinical animal model for testing drugs with potential effects on myeloproliferative neoplasms (MPNs), we first performed a detailed phenotypic characterization of Cre-inducible transgenic JAK2-V617F mice. Deleting the conditional mouse Jak2-knockout alleles increased erythropoiesis and accentuated the polycythemia vera phenotype, but did not alter platelet or granulocyte levels. In a transplantation assay, JAK2-V617F(+) BM cells had an advantage over wild-type competitor cells. Using this competitive repopulation assay, we compared the effects of INC424 (ruxolitinib), a dual Jak1/Jak2 inhibitor, and hydroxyurea (HU). HU led to weight loss, but did not reduce spleen weight. The hematologic parameters were lowered and a slight decrease of the mutant allele burden was noted. INC424 had little effect on body weight, but strongly decreased spleen size and rapidly normalized RBC and neutrophil parameters. No significant decrease in the mutant allele burden was observed. INC424 reduced the phospho-Stat5 levels, whereas HU strongly increased phospho-Stat5, most likely because of the elevated erythropoietin levels in response to the HU-induced anemia. This compensatory increase in JAK/STAT signaling may counteract the beneficial effects of cytoreduction at higher doses of HU and represents an adverse effect that should be avoided.
Regulation of DNA repair in serum-stimulated xeroderma pigmentosum cells
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gupta, P.K.; Sirover, M.A.
1984-10-01
The regulation of DNA repair during serum stimulation of quiescent cells was examined in normal human cells, in fibroblasts from three xeroderma pigmentosum complementation groups (A, C, and D), in xeroderma pigmentosum variant cells, and in ataxia telangiectasia cells. The regulation of nucleotide excision repair was examined by exposing cells to ultraviolet irradiation at discrete intervals after cell stimulation. Similarly, base excision repair was quantitated after exposure to methylmethane sulfonate. WI-38 normal human diploid fibroblasts, xeroderma pigmentosum variant cells, as well as ataxia telangiectasia cells enhanced their capacity for both nucleotide excision repair and for base excision repair prior tomore » their enhancement of DNA synthesis. Further, in each cell strain, the base excision repair enzyme uracil DNA glycosylase was increased prior to the induction of DNA polymerase using the identical cells to quantitate each activity. In contrast, each of the three xeroderma complementation groups that were examined failed to increase their capacity for nucleotide excision repair above basal levels at any interval examined. This result was observed using either unscheduled DNA synthesis in the presence of 10 mM hydroxyurea or using repair replication in the absence of hydroxyurea to quantitate DNA repair. However, each of the three complementation groups normally regulated the enhancement of base excision repair after methylmethane sulfonate exposure and each induced the uracil DNA glycosylase prior to DNA synthesis. 62 references, 3 figures, 2 tables.« less
Hydroxyurea inhibits parvovirus B19 replication in erythroid progenitor cells.
Bonvicini, Francesca; Bua, Gloria; Conti, Ilaria; Manaresi, Elisabetta; Gallinella, Giorgio
2017-07-15
Parvovirus B19 (B19V) infection is restricted to erythroid progenitor cells (EPCs) of the human bone marrow, leading to transient arrest of erythropoiesis and severe complications mainly in subjects with underlying hematological disorders or with immune system deficits. Currently, there are no specific antiviral drugs for B19V treatment, but identification of compounds inhibiting B19V replication can be pursued by a drug repositioning strategy. In this frame, the present study investigates the activity of hydroxyurea (HU), the only disease-modifying therapy approved for sickle cell disease (SCD), towards B19V replication in the two relevant cellular systems, the UT7/EpoS1 cell line and EPCs. Results demonstrate that HU inhibits B19V replication with EC 50 values of 96.2µM and 147.1µM in UT7/EpoS1 and EPCs, respectively, providing experimental evidence of the antiviral activity of HU towards B19V replication, and confirming the efficacy of a drug discovery process by drug repositioning strategy. The antiviral activity occurs in vitro at concentrations lower than those affecting cellular DNA replication and viability, and at levels measured in plasma samples of SCD patients undergoing HU therapy. HU might determine a dual beneficial effect on SCD patients, not only for the treatment of the disease but also towards a virus responsible for severe complications. Copyright © 2017 Elsevier Inc. All rights reserved.
Hydroxyurea for nontransfusion-dependent β-thalassemia: A systematic review and meta-analysis.
Algiraigri, Ali H; Wright, Nicola A M; Paolucci, Elizabeth Oddone; Kassam, Aliya
2017-09-01
Nontransfusion-dependent β-thalassemia (NTDβT) syndromes consist of β-thalassemia intermedia and moderate hemoglobin E/β thalassemias. They are characterized by varying degrees of chronic anemia and a wide spectrum of complications due to ineffective erythropoiesis and iron overload from chronic transfusions. Hydroxyurea (HU), an oral chemotherapeutic drug, is anticipated to decrease disease severity. We performed a meta-analysis to evaluate the clinical efficacy and safety of HU in NTDβT patients of any age. MEDLINE, EMBASE, Cochrane databases, and major conference proceedings for studies that assessed HU in NTDβT patients were searched. Qualities of eligible studies were assessed by National Institutes of Health tools. Seventeen studies, collectively involving 709 patients, fulfilled the eligibility criteria. HU was associated with a significant decrease in transfusion need in severe NTDβT with complete and overall (≥50%) response rates of 42% and 79%, respectively. For mild NTDβT, HU was effective in raising hemoglobin by 1g/L in 64% of patients. HU appears to be effective, well tolerated, and associated with mild and transient adverse events. NTDβT patients may benefit from a trial of HU, although large randomized clinical trials assessing its efficacy should be conducted to confirm the findings of this meta-analysis and to assess its long-term toxicity and response sustainability. Copyright © 2017 King Faisal Specialist Hospital & Research Centre. Published by Elsevier B.V. All rights reserved.
Anagrelide reduces thrombotic risk in essential thrombocythaemia vs. hydroxyurea plus aspirin.
Dombi, Péter; Illés, Árpád; Demeter, Judit; Homor, Lajos; Simon, Zsofia; Karadi, Eva; Udvardy, Miklos; Egyed, Miklos
2017-02-01
To evaluate the reduction in thrombotic events (TE) in patients with essential thrombocythaemia (ET) treated with anagrelide versus hydroxyurea + aspirin (HU + ASA). A questionnaire was developed using 2008 WHO diagnostic criteria, and thrombotic risk factors were stratified according to Landolfi criteria. Through questionnaire completion, clinicians at Hungarian haematological centres entered data into the Hungarian MPN Registry on patients with myeloproliferative neoplasms. Based on ET registry data, TEs in anagrelide-treated patients (n = 139) were compared with HU + ASA-treated patients (n = 141). Patients were followed up for (median) 6 yr. TEs were reported in significantly fewer anagrelide-treated patients versus HU + ASA (15.1% versus 49.6%; P < 0.001). Numbers of major arterial and major venous events were similar between the groups, although there were over fivefold more minor arterial and minor venous events in the HU + ASA group (P < 0.001). While median age at diagnosis was older and length of follow-up shorter in the HU + ASA group (P < 0.05), this did not influence TE incidence; medication and TE before diagnosis only influenced TE incidence. Anagrelide significantly decreased the number of patients experiencing minor arterial and minor venous TEs versus HU + ASA over 6 yr. Risk of TE after diagnosis was significantly increased if the patient had TE before diagnosis. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Adachi, Hideki; Uematsu, Yasuaki; Yamada, Toru
2016-11-15
To evaluate the suitability of the rat Pig-a assay on reticulocytes (PIGRET assay) as a short-term test, red blood cell (RBC) Pig-a and PIGRET assays after single doses with hydroxyurea (HU) and melphalan (L-PAM) were conducted and the results of both assays were compared. HU was administered once orally to male SD rats at 250, 500 and 1000mg/kg, and both assays were conducted using peripheral blood withdrawn from the jugular vein at 1, 2 and 4 weeks after dosing. L-PAM was administered at 1.25, 2.5 and 5mg/kg in the same manner. L-PAM produced significant dose-dependent increases in mutant frequencies in the PIGRET assay after single oral doses, but did not produce dose-dependent increases in mutant frequencies in the RBC Pig-a assay. These results suggest that the PIGRET assay is more sensitive for the evaluation of the mutagenic potential of L-PAM than the RBC Pig-a assay. In contrast, HU, a clastogenic but not DNA-reactive compound, gave negative results in both assays. The results with these 2 chemicals indicate that the single-dose PIGRET assay in rats has the potential to properly detect DNA-reactive compounds that directly cause DNA damage in a short-term assay. Copyright © 2016 Elsevier B.V. All rights reserved.
Effects of hydroxyurea on blood rheology in sickle cell anemia: A two-years follow-up study.
Lemonne, Nathalie; Möckesch, Berenike; Charlot, Keyne; Garnier, Yohann; Waltz, Xavier; Lamarre, Yann; Antoine-Jonville, Sophie; Etienne-Julan, Maryse; Hardy-Dessources, Marie-Dominique; Romana, Marc; Connes, Philippe
2017-01-01
The aim of the present study was to test the effects of hydroxyurea (HU) therapy on clinical, hematological and hemorheological parameters in adult patients with sickle cell anemia (SCA). Hematological and hemorheological parameters were measured in 28 SCA patients before HU therapy (i.e., baseline) and at 6, 12 and 24 months of treatment. RBC deformability was determined by ektacytometry at 30 Pa. RBC aggregation properties were investigated by light-backscatter method. Blood viscosity was measured at 225 s-1 by a cone-plate viscometer. The rates of vaso-occlusive crises and acute chest syndrome were lower at 1 and 2 years of HU therapy compared to baseline. The proportion of patients with leg ulcers tended to decrease after 2 years of treatment. Hemoglobin oxygen saturation improved with HU therapy. HU therapy induced a decrease of platelet and white blood cell counts and a rise in fetal hemoglobin level and mean cell volume. While hemoglobin concentrations increased under HU, blood viscosity remained unchanged all along the study. RBC deformability increased over baseline values at 6 months of HU therapy and continued to rise until the end of the follow-up period. In conclusion, the improvement in RBC deformability probably compensates the increase of hemoglobin on blood viscosity and participates to the improvement of the clinical status of patients.
Pediatric Perioperative Nurses and the Ethics of Organ Donation After Cardiac Death.
Austin, Elizabeth A; Lovett, Pamela; Moore, Wendy C; Zuzarte, Ingrid
2018-04-01
Pediatric perioperative nurses are experiencing increased opportunities to participate in donations after cardiac death. An increased public awareness regarding transplantation has inspired more people to donate than in previous years. The demand for transplantable organs has led to opportunities that have increased donor candidates including living donors and cardiac death donors. Cardiac death in children is often sudden and unexpected, and is an emotional time not only for the family members but also for the hospital staff members, including perioperative nurses. However, when perioperative nurses adhere to standards and guidelines, they can perform their responsibilities in an ethical and compassionate manner and assist their team in doing so. This article reviews the guiding principles of pediatric organ donation after cardiac death, the phases of the process, and the ethical and moral issues surrounding donation. © AORN, Inc, 2018.
International Pediatric MS Study Group Clinical Trials Summit: meeting report.
Chitnis, Tanuja; Tardieu, Marc; Amato, Maria Pia; Banwell, Brenda; Bar-Or, Amit; Ghezzi, Angelo; Kornberg, Andrew; Krupp, Lauren B; Pohl, Daniela; Rostasy, Kevin; Tenembaum, Silvia; Waubant, Emmanuelle; Wassmer, Evangeline
2013-03-19
Pediatric studies for new biological agents are mandated by recent legislation, necessitating careful thought to evaluation of emerging multiple sclerosis (MS) therapies in children with MS. Challenges include a small patient population, the lack of prior randomized clinical trials, and ethical concerns. The goal of this meeting was to assess areas of consensus regarding clinical trial design and outcome measures among academic experts involved in pediatric MS care and research. The Steering Committee of the International Pediatric MS Study Group identified key focus areas for discussion. A total of 69 meeting attendees were assembled, including 35 academic experts. Regulatory and pharmaceutical representatives also attended, and provided input, which informed academic expert consensus decisions. The academic experts agreed that clinical trials were necessary in pediatric MS to obtain pharmacokinetic, safety and efficacy data, and regulatory approval allowing for greater medication access. The academic experts agreed that relapse was an appropriate primary outcome measure for phase III pediatric trials. An international standardized cognitive battery was identified. The pros and cons of various trial designs were discussed. Guidelines surrounding MRI studies, pharmacokinetics, pharmacodynamics, and registries were developed. The academic experts agreed that given the limited subject pool, a stepwise approach to the launch of clinical trials for the most promising medications is necessary in order to ensure study completion. Alternative approaches could result in unethical exposure of patients to trial conditions without gaining knowledge. Consensus points for conduct of clinical trials in the rare disease pediatric MS were identified amongst a panel of academic experts, informed by regulatory and industry stakeholders.
Moler, Frank W.; Silverstein, Faye S.; Meert, Kathleen L.; Clark, Amy E.; Holubkov, Richard; Browning, Brittan; Slomine, Beth S.; Christensen, James R.; Dean, Michael
2014-01-01
Objective To describe the rationale, timeline, study design, and protocol overview of the Therapeutic Hypothermia after Pediatric Cardiac Arrest trials. Design Multicenter randomized controlled trials. Setting Pediatric intensive care and cardiac ICUs in the United States and Canada. Patients Children from 48 hours to 18 years old, who have return of circulation after cardiac arrest, who meet trial eligibility criteria, and whose guardians provide written consent. Interventions Therapeutic hypothermia or therapeutic normothermia. Measurements and Main Results From concept inception in 2002 until trial initiation in 2009, 7 years were required to plan and operationalize the Therapeutic Hypothermia after Pediatric Cardiac Arrest trials. Two National Institute of Child Health and Human Development clinical trial planning grants (R21 and R34) supported feasibility assessment and protocol development. Two clinical research networks, Pediatric Emergency Care Applied Research Network and Collaborative Pediatric Critical Care Research Network, provided infrastructure resources. Two National Heart Lung Blood Institute U01 awards provided funding to conduct separate trials of in-hospital and out-of-hospital cardiac arrest. A pilot vanguard phase that included half the clinical sites began on March 9, 2009, and this was followed by full trial funding through 2015. Conclusions Over a decade will have been required to plan, design, operationalize, and conduct the Therapeutic Hypothermia after Pediatric Cardiac Arrest trials. Details described in this report, such as participation of clinical research networks and clinical trial planning grants utilization, may be of utility for individuals who are planning investigator-initiated, federally supported clinical trials. PMID:23842585
Avila, M L; Brandão, L R; Williams, S; Ward, L C; Montoya, M I; Stinson, J; Kiss, A; Lara-Corrales, I; Feldman, B M
2016-08-01
Our goal was to conduct the item generation and piloting phases of a new discriminative and evaluative tool for pediatric post-thrombotic syndrome. We followed a formative model for the development of the tool, focusing on the signs/symptoms (items) that define post-thrombotic syndrome. For item generation, pediatric thrombosis experts and subjects diagnosed with extremity post-thrombotic syndrome during childhood nominated items. In the piloting phase, items were cross-sectionally measured in children with limb deep vein thrombosis to examine item performance. Twenty-three experts and 16 subjects listed 34 items, which were then measured in 140 subjects with previous diagnosis of limb deep vein thrombosis (70 upper extremity and 70 lower extremity). The items with strongest correlation with post-thrombotic syndrome severity and largest area under the curve were pain (in older children), paresthesia, and swollen limb for the upper extremity group, and pain (in older children), tired limb, heaviness, tightness and paresthesia for the lower extremity group. The diagnostic properties of the items and their correlations with post-thrombotic syndrome severity varied according to the assessed venous territory. The information gathered in this study will help experts decide which item should be considered for inclusion in the new tool. Copyright © 2016 Elsevier Ltd. All rights reserved.
Ethical issues in pediatric oncology phase I-II trials based on a mother's point of view.
Oppenheim, D; Geoerger, B; Hartmann, O
2005-11-01
Phase I-II trials are developing in Pediatrics and raise many complex relational, psychological and ethical issues. We present and discuss these based on an interview in a pediatric oncology setting, with a mother who accepted that her daughter be included in such trials and who expressed why she accepted with great sensitivity and profoundness. She explained that after many years of inefficient treatments she had lost all her landmarks and was ready to accept any proposition, even those she would have considered unacceptable earlier. She did not know whether there is a limit to what is acceptable. Her only objective was to gain any time possible in order to continue living with her daughter. She found it important that the research doctor be different from the doctor involved in patient care, and that the latter remains the major decision-maker and correspondent: thus the child's best interests take precedence over that of research. Interviews with the psycho-oncologist can help the parents and the doctors gain a better insight into the various aspects, rational and irrational, conscious and unconscious, involved in the proposition to participate in a clinical trial and in the parents' or the child's acceptance or refusal.
Taborri, Juri; Scalona, Emilia; Palermo, Eduardo; Rossi, Stefano; Cappa, Paolo
2015-09-23
Gait-phase recognition is a necessary functionality to drive robotic rehabilitation devices for lower limbs. Hidden Markov Models (HMMs) represent a viable solution, but they need subject-specific training, making data processing very time-consuming. Here, we validated an inter-subject procedure to avoid the intra-subject one in two, four and six gait-phase models in pediatric subjects. The inter-subject procedure consists in the identification of a standardized parameter set to adapt the model to measurements. We tested the inter-subject procedure both on scalar and distributed classifiers. Ten healthy children and ten hemiplegic children, each equipped with two Inertial Measurement Units placed on shank and foot, were recruited. The sagittal component of angular velocity was recorded by gyroscopes while subjects performed four walking trials on a treadmill. The goodness of classifiers was evaluated with the Receiver Operating Characteristic. The results provided a goodness from good to optimum for all examined classifiers (0 < G < 0.6), with the best performance for the distributed classifier in two-phase recognition (G = 0.02). Differences were found among gait partitioning models, while no differences were found between training procedures with the exception of the shank classifier. Our results raise the possibility of avoiding subject-specific training in HMM for gait-phase recognition and its implementation to control exoskeletons for the pediatric population.
Taborri, Juri; Scalona, Emilia; Palermo, Eduardo; Rossi, Stefano; Cappa, Paolo
2015-01-01
Gait-phase recognition is a necessary functionality to drive robotic rehabilitation devices for lower limbs. Hidden Markov Models (HMMs) represent a viable solution, but they need subject-specific training, making data processing very time-consuming. Here, we validated an inter-subject procedure to avoid the intra-subject one in two, four and six gait-phase models in pediatric subjects. The inter-subject procedure consists in the identification of a standardized parameter set to adapt the model to measurements. We tested the inter-subject procedure both on scalar and distributed classifiers. Ten healthy children and ten hemiplegic children, each equipped with two Inertial Measurement Units placed on shank and foot, were recruited. The sagittal component of angular velocity was recorded by gyroscopes while subjects performed four walking trials on a treadmill. The goodness of classifiers was evaluated with the Receiver Operating Characteristic. The results provided a goodness from good to optimum for all examined classifiers (0 < G < 0.6), with the best performance for the distributed classifier in two-phase recognition (G = 0.02). Differences were found among gait partitioning models, while no differences were found between training procedures with the exception of the shank classifier. Our results raise the possibility of avoiding subject-specific training in HMM for gait-phase recognition and its implementation to control exoskeletons for the pediatric population. PMID:26404309
Chua, Siew-Siang; Choo, Sim-Mei; Sulaiman, Che Zuraini; Omar, Asma; Thong, Meow-Keong
2017-01-01
Background and purpose Drug administration errors are more likely to reach the patient than other medication errors. The main aim of this study was to determine whether the sharing of information on drug administration errors among health care providers would reduce such problems. Patients and methods This study involved direct, undisguised observations of drug administrations in two pediatric wards of a major teaching hospital in Kuala Lumpur, Malaysia. This study consisted of two phases: Phase 1 (pre-intervention) and Phase 2 (post-intervention). Data were collected by two observers over a 40-day period in both Phase 1 and Phase 2 of the study. Both observers were pharmacy graduates: Observer 1 just completed her undergraduate pharmacy degree, whereas Observer 2 was doing her one-year internship as a provisionally registered pharmacist in the hospital under study. A drug administration error was defined as a discrepancy between the drug regimen received by the patient and that intended by the prescriber and also drug administration procedures that did not follow standard hospital policies and procedures. Results from Phase 1 of the study were analyzed, presented and discussed with the ward staff before commencement of data collection in Phase 2. Results A total of 1,284 and 1,401 doses of drugs were administered in Phase 1 and Phase 2, respectively. The rate of drug administration errors reduced significantly from Phase 1 to Phase 2 (44.3% versus 28.6%, respectively; P<0.001). Logistic regression analysis showed that the adjusted odds of drug administration errors in Phase 1 of the study were almost three times that in Phase 2 (P<0.001). The most common types of errors were incorrect administration technique and incorrect drug preparation. Nasogastric and intravenous routes of drug administration contributed significantly to the rate of drug administration errors. Conclusion This study showed that sharing of the types of errors that had occurred was significantly associated with a reduction in drug administration errors. PMID:28356748
Auchus, Richard J.; Witchel, Selma Feldman; Leight, Kelly R.; Aisenberg, Javier; Azziz, Ricardo; Bachega, Tânia A.; Baker, Linda A.; Baratz, Arlene B.; Baskin, Laurence S.; Berenbaum, Sheri A.; Breault, David T.; Cerame, Barbara I.; Conway, Gerard S.; Eugster, Erica A.; Fracassa, Stephanie; Gearhart, John P.; Geffner, Mitchell E.; Harris, Katharine B.; Hurwitz, Richard S.; Katz, Aviva L.; Kalro, Brinda N.; Lee, Peter A.; Alger Lin, Gretchen; Loechner, Karen J.; Marshall, Ian; Merke, Deborah P.; Migeon, Claude J.; Miller, Walter L.; Nenadovich, Tamara L.; Oberfield, Sharon E.; Pass, Kenneth A.; Poppas, Dix P.; Lloyd-Puryear, Michele A.; Quigley, Charmian A.; Riepe, Felix G.; Rink, Richard C.; Rivkees, Scott A.; Sandberg, David E.; Schaeffer, Traci L.; Schlussel, Richard N.; Schneck, Francis X.; Seely, Ellen W.; Snyder, Diane; Speiser, Phyllis W.; Therrell, Bradford L.; VanRyzin, Carol; Vogiatzi, Maria G.; Wajnrajch, Michael P.; White, Perrin C.; Zuckerman, Alan E.
2010-01-01
Patients with rare and complex diseases such as congenital adrenal hyperplasia (CAH) often receive fragmented and inadequate care unless efforts are coordinated among providers. Translating the concepts of the medical home and comprehensive health care for individuals with CAH offers many benefits for the affected individuals and their families. This manuscript represents the recommendations of a 1.5 day meeting held in September 2009 to discuss the ideal goals for comprehensive care centers for newborns, infants, children, adolescents, and adults with CAH. Participants included pediatric endocrinologists, internal medicine and reproductive endocrinologists, pediatric urologists, pediatric surgeons, psychologists, and pediatric endocrine nurse educators. One unique aspect of this meeting was the active participation of individuals personally affected by CAH as patients or parents of patients. Representatives of Health Research and Services Administration (HRSA), New York-Mid-Atlantic Consortium for Genetics and Newborn Screening Services (NYMAC), and National Newborn Screening and Genetics Resource Center (NNSGRC) also participated. Thus, this document should serve as a “roadmap” for the development phases of comprehensive care centers (CCC) for individuals and families affected by CAH. PMID:21274448
Ozkaynak, M Fevzi; Sahdev, Indira; Gross, Thomas G; Levine, John E; Cheerva, Alexandra C; Richards, Michael K; Rozans, Marta K; Shaw, Peter J; Kadota, Richard P
2008-03-01
Limited information is available regarding the use of amifostine in pediatric hematopoietic stem cell transplant (HSCT) patients. Melphalan, carboplatin, etoposide +/- cyclophosphamide is a commonly used preparatory regimen in pediatric solid tumor HSCT. Therefore, we decided to determine the feasibility of the addition of amifostine (750 mg/m b.i.d. x 4 d) to melphalan (200 mg/m), carboplatin (1200 mg/m), and etoposide (800 mg/m) (level 1) and escalating doses of cyclophosphamide (3000 mg/m and 3800 mg/m, levels 2 and 3, respectively) followed by autologous HSCT. Thirty-two patients with a variety of pediatric solid tumors were studied. Seventeen patients were accrued at level 1, 9 at level 2, and 6 at level 3. Major toxicities during the administration of the preparatory regimen were hypocalcemia, emesis, and hypotension. Hypocalcemia required aggressive calcium supplementation during the conditioning phase. No dose limiting toxicities were encountered at level 3. Amifostine at 750 mg/m b.i.d. for 4 days can be administered with a double alkylator regimen consisting of melphalan (200 mg/m), cyclophosphamide (up to 3800 mg/m), carboplatin (1200 mg/m), and etoposide (800 mg/m) with manageable toxicities.
Ying, Gui-shuang; Maguire, Maureen; Quinn, Graham; Kulp, Marjean Taylor; Cyert, Lynn
2011-12-28
To evaluate, by receiver operating characteristic (ROC) analysis, the accuracy of three instruments of refractive error in detecting eye conditions among 3- to 5-year-old Head Start preschoolers and to evaluate differences in accuracy between instruments and screeners and by age of the child. Children participating in the Vision In Preschoolers (VIP) Study (n = 4040), had screening tests administered by pediatric eye care providers (phase I) or by both nurse and lay screeners (phase II). Noncycloplegic retinoscopy (NCR), the Retinomax Autorefractor (Nikon, Tokyo, Japan), and the SureSight Vision Screener (SureSight, Alpharetta, GA) were used in phase I, and Retinomax and SureSight were used in phase II. Pediatric eye care providers performed a standardized eye examination to identify amblyopia, strabismus, significant refractive error, and reduced visual acuity. The accuracy of the screening tests was summarized by the area under the ROC curve (AUC) and compared between instruments and screeners and by age group. The three screening tests had a high AUC for all categories of screening personnel. The AUC for detecting any VIP-targeted condition was 0.83 for NCR, 0.83 (phase I) to 0.88 (phase II) for Retinomax, and 0.86 (phase I) to 0.87 (phase II) for SureSight. The AUC was 0.93 to 0.95 for detecting group 1 (most severe) conditions and did not differ between instruments or screeners or by age of the child. NCR, Retinomax, and SureSight had similar and high accuracy in detecting vision disorders in preschoolers across all types of screeners and age of child, consistent with previously reported results at specificity levels of 90% and 94%.
Guix-Comellas, Eva Maria; Rozas-Quesada, Librada; Velasco-Arnaiz, Eneritz; Ferres-Canals, Ariadna; Estrada-Masllorens, Joan Maria; Force-Sanmartín, Enriqueta; Noguera-Julian, Antoni
2018-05-03
To evaluate the association of a new nursing intervention on the adherence to antituberculosis treatment in a pediatric cohort (<18 years). Tuberculosis remains a public health problem worldwide. The risk of developing tuberculosis after primary infection and its severity are higher in children. Proper adherence to antituberculosis treatment is critical for disease control. Non-randomized controlled trial; Phase 1, retrospective (2011-2013), compared with Phase 2, prospective with intervention (2015-2016), in a referral center for pediatric tuberculosis in Spain (NCT03230409). A total of 359 patients who received antituberculosis drugs after close contact with a smear-positive patient (primary chemoprophylaxis) or were treated for latent tuberculosis infection or tuberculosis disease were included, 261 in Phase 1 and 98 in Phase 2. In phase 2, a new nurse-led intervention was implemented in all patients and included two educational steps (written information in the child's native language and follow-up telephone calls) and two monitoring steps (Eidus-Hamilton test and follow-up questionnaire) that were exclusively carried out by nurses. Adherence to antituberculosis treatment increased from 74.7% in Phase 1 to 87.8% in Phase 2 (p=0.014; Chi-square test), after the implementation of the nurse-led intervention. In Phase 2, non-adherence was only associated with being born abroad (28.6% versus 7.8%; p=0.019; Chi-square test) and with foreign origin families (27.3% versus 0%; p<0.0001; Chi-square test). The nurse-led intervention was associated to an increase in adherence to antituberculosis treatment. Immigrant-related variables remained major risk factors for sub-optimal adherence in a low-endemic setting. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Dupuis, L Lee; Kelly, Kara M; Krischer, Jeffrey P; Langevin, Anne-Marie; Tamura, Roy N; Xu, Ping; Chen, Lu; Kolb, E Anders; Ullrich, Nicole J; Sahler, Olle Jane Z; Hendershot, Eleanor; Stratton, Ann; Sung, Lillian; McLean, Thomas W
2018-03-15
Chemotherapy-induced nausea and vomiting remain common, distressing side effects of chemotherapy. It has been reported that acupressure prevents chemotherapy-induced nausea in adults, but it has not been well studied in children. In this multicenter, prospective, randomized, single-blind, sham-controlled trial, the authors compared acute-phase nausea severity in patients ages 4 to 18 years who were receiving highly emetic chemotherapy using standard antiemetic agents combined with acupressure wrist bands, the most common type of acupressure, versus sham bands. Patients wore acupressure or sham bands continuously on each day of chemotherapy and for up to 7 days afterward. Chemotherapy-induced nausea severity in the delayed phase and chemotherapy-induced vomiting control in the acute and delayed phases also were compared. Of the 187 patients randomized, 165 contributed nausea severity assessments during the acute phase. Acupressure bands did not reduce the severity of chemotherapy-induced nausea in the acute phase (odds ratio [OR], 1.33; 95% confidence limits, 0.89-2.00, in which an OR <1.00 favored acupressure) or in the delayed phase (OR, 1.23; 95% CL, 0.75-2.01). Furthermore, acupressure bands did not improve daily vomiting control during the acute phase (OR, 1.57; 95% CL, 0.95-2.59) or the delayed phase (OR, 0.84; 95% CL, 0.45-1.58). No serious adverse events were reported. Acupressure bands were safe but did not improve chemotherapy-induced nausea or vomiting in pediatric patients who were receiving highly emetic chemotherapy. Cancer 2018;124:1188-96. © 2017 American Cancer Society. © 2017 American Cancer Society.
Singer, Kanakadurga; Subbaiah, Perla; Hutchinson, Raymond; Odetola, Folafoluwa; Shanley, Thomas P
2011-11-01
To describe the clinical course, resource use, and mortality of patients with leukemia admitted to the pediatric intensive care unit with sepsis and nonsepsis diagnoses over a 10-yr period. Retrospective analysis. Tertiary medical-surgical pediatric intensive care unit at C.S. Mott Children's Hospital, University of Michigan. All patients with leukemia admitted to the pediatric intensive care unit from January 1, 1998, to December 31, 2008. None; chart review. Clinical course was characterized by demographics, leukemia diagnosis, phase of therapy, leukocyte count on admission, presence of sepsis, steroid administration, intensity of care, and Pediatric Risk of Mortality score on admission to the pediatric intensive care unit. The primary outcome was survival to pediatric intensive care unit discharge. Among 68 single admissions to the pediatric intensive care unit with leukemia during the study period, 33 (48.5%) were admitted with sepsis. Admission to the pediatric intensive care unit for sepsis was associated with greater compromise of hemodynamic and renal function and use of stress dose steroids (p = .016), inotropic and/or vasopressor drugs (p = .01), and renal replacement therapy (p = .028) than nonsepsis admission. There was higher mortality among children with sepsis than other diagnoses (52% vs. 17%, p = .004). Also, mortality among children with sepsis was higher among those with acute lymphoblastic leukemia (60% vs. 44%) compared with acute myelogenous leukemia. Administration of stress dose steroids was associated with higher mortality (50% vs. 17%, p = .005) and neutropenia. Patients with acute lymphoblastic leukemia and sepsis showed the greatest mortality and resource use. Patients with acute leukemia and sepsis had a much higher mortality rate compared with previously described sepsis mortality rates for the general pediatric intensive care unit patient populations. Patients who received steroids had an increased mortality rate, but given the retrospective nature of this study, we maintain a position of equipoise with regard to this association. Variation in mortality and resource use by leukemia type suggests further research is needed to develop targeted intervention strategies to enhance patient outcomes.
Ewing sarcoma of the rib with normal blood flow and blood pool imagings on a 3-phase bone scan.
Alfeeli, Mahmoud A; Naddaf, Sleiman Y; Syed, Ghulam M S
2005-09-01
Ewing sarcoma is the second most common pediatric malignant bone tumor. It usually presents as a hot spot on a 3-phase bone scan as a result of increased vascularity of the tumor and new bone formation. However, aggressive Ewing sarcoma can also appear as a cold lesion. We present the features of a Ewing sarcoma of the rib on a 3-phase bone scan in a child who was being investigated for rib fracture after trauma.
Knebel, William; Palmen, Mary; Dowell, James A; Gastonguay, Marc
2008-07-01
This analysis quantifies the population pharmacokinetics of subcutaneous and intravenous epoetin delta, an epoetin produced in a human cell line, in pediatric patients with chronic kidney disease and estimates the effects of covariate factors on epoetin delta and epoetin alfa pharmacokinetic parameters. Erythropoietin serum concentration data, taken from a phase III study conducted in 60 patients aged 1 to 17 years, were best described by a 1-compartment model with first-order absorption and elimination. The typical point estimates were clearance (0.268 L/h), central volume of distribution (1.03 L), absorption rate constant (0.0554 h(-1)), and bioavailability (0.708) for a 35-kg male < or = 10 years who was predialysis and on subcutaneous epoetin delta treatment. Erythropoietin pharmacokinetic parameters were similar in pediatric patients as compared with adults when scaled by weight. The subcutaneous administration of epoetin alfa exhibited lower systemic bioavailability than subcutaneous administration of epoetin delta.
Robinson, Giles W.; Orr, Brent A.; Wu, Gang; Gururangan, Sridharan; Lin, Tong; Qaddoumi, Ibrahim; Packer, Roger J.; Goldman, Stewart; Prados, Michael D.; Desjardins, Annick; Chintagumpala, Murali; Takebe, Naoko; Kaste, Sue C.; Rusch, Michael; Allen, Sariah J.; Onar-Thomas, Arzu; Stewart, Clinton F.; Fouladi, Maryam; Boyett, James M.; Gilbertson, Richard J.; Curran, Tom; Ellison, David W.; Gajjar, Amar
2015-01-01
Purpose Two phase II studies assessed the efficacy of vismodegib, a sonic hedgehog (SHH) pathway inhibitor that binds smoothened (SMO), in pediatric and adult recurrent medulloblastoma (MB). Patients and Methods Adult patients enrolled onto PBTC-025B and pediatric patients enrolled onto PBTC-032 were treated with vismodegib (150 to 300 mg/d). Protocol-defined response, which had to be sustained for 8 weeks, was confirmed by central neuroimaging review. Molecular tests to identify patterns of response and insensitivity were performed when tissue was available. Results A total of 31 patients were enrolled onto PBTC-025B, and 12 were enrolled onto PBTC-032. Three patients in PBTC-025B and one in PBTC-032, all with SHH-subgroup MB (SHH-MB), exhibited protocol-defined responses. Progression-free survival (PFS) was longer in those with SHH-MB than in those with non-SHH–MB, and prolonged disease stabilization occurred in 41% of patient cases of SHH-MB. Among those with SHH-MB, loss of heterozygosity of PTCH1 was associated with prolonged PFS, and diffuse staining of P53 was associated with reduced PFS. Whole-exome sequencing identified mutations in SHH genes downstream from SMO in four of four tissue samples from nonresponders and upstream of SMO in two of four patients with favorable responses. Conclusion Vismodegib exhibits activity against adult recurrent SHH-MB but not against recurrent non-SHH–MB. Inadequate accrual of pediatric patients precluded conclusions in this population. Molecular analyses support the hypothesis that SMO inhibitor activity depends on the genomic aberrations within the tumor. Such inhibitors should be advanced in SHH-MB studies; however, molecular and genomic work remains imperative to identify target populations that will truly benefit. PMID:26169613
Getz, Kelly D.; Li, Yimei; Alonzo, Todd A.; Hall, Matthew; Gerbing, Robert B.; Sung, Lillian; Huang, Yuan-Shung; Arnold, Staci; Seif, Alix E.; Miller, Tamara P.; Bagatell, Rochelle; Fisher, Brian T.; Adamson, Peter C.; Gamis, Alan; Keren, Ron; Aplenc, Richard
2015-01-01
Background A better understanding of drivers of treatment costs may help identify effective cost containment strategies and prioritize resources. We aimed to develop a method for estimating inpatient costs for pediatric patients with acute myeloid leukemia (AML) enrolled on NCI-funded Phase III trials, compare costs between AAML0531 treatment arms (standard chemotherapy ± gemtuzumab ozogamicin (GMTZ)), and evaluate primary drivers of costs for newly diagnosed pediatric AML. Procedure Patients from the AAML0531 trial were matched on hospital, sex, and dates of birth and diagnosis to the Pediatric Health Information Systems (PHIS) database to obtain daily billing data. Inpatient treatment costs were calculated as adjusted charges multiplied by hospital-specific cost-to-charge ratios. Generalized linear models were used to compare costs between treatment arms and courses, and by patient characteristics. Results Inpatient costs did not differ by randomized treatment arm. Costs varied by course with stem cell transplant being most expensive, followed by Intensification II (cytarabine/mitoxantrone) and Induction I (cytarabine/daunorubicin/etoposide). Room/board and pharmacy were the largest contributors to inpatient treatment cost, representing 74% of the total cost. Higher AML risk group (P = 0.0003) and older age (P < 0.0001) were associated with significantly higher daily inpatient cost. Conclusions Costs from external data sources can be successfully integrated into NCI-funded Phase III clinical trials. Inpatient treatment costs did not differ by GMTZ exposure but varied by chemotherapy course. Variation in cost by course was driven by differences in duration of hospitalization through room/board charges as well as increased clinical and pharmacy charges in specific courses. Pediatr Blood Cancer PMID:25946708
Progesterone for Neuroprotection in Pediatric Traumatic Brain Injury
Robertson, Courtney L.; Fidan, Emin; Stanley, Rachel M.; MHSA; Noje, Corina; Bayir, Hülya
2016-01-01
Objective To provide an overview of the preclinical literature on progesterone for neuroprotection after traumatic brain injury (TBI), and to describe unique features of developmental brain injury that should be considered when evaluating the therapeutic potential for progesterone treatment after pediatric TBI. Data Sources National Library of Medicine PubMed literature review. Data Selection The mechanisms of neuroprotection by progesterone are reviewed, and the preclinical literature using progesterone treatment in adult animal models of TBI are summarized. Unique features of the developing brain that could either enhance or limit the efficacy of neuroprotection by progesterone are discussed, and the limited preclinical literature using progesterone after acute injury to the developing brain is described. Finally, the current status of clinical trials of progesterone for adult TBI is reviewed. Data Extraction and Synthesis Progesterone is a pleotropic agent with beneficial effects on secondary injury cascades that occur after TBI, including cerebral edema, neuroinflammation, oxidative stress, and excitotoxicity. More than 40 studies have used progesterone for treatment after TBI in adult animal models, with results summarized in tabular form. However, very few studies have evaluated progesterone in pediatric animal models of brain injury. To date, two human Phase II trials of progesterone for adult TBI have been published, and two multi-center Phase III trials are underway. Conclusions The unique features of the developing brain from that of a mature adult brain make it necessary to independently study progesterone in clinically relevant, immature animal models of TBI. Additional preclinical studies could lead to the development of a novel neuroprotective therapy that could reduce the long-term disability in head-injured children, and could potentially provide benefit in other forms of pediatric brain injury (global ischemia, stroke, statue epilepticus). PMID:25581631
Silber, Steven A; Diro, Ermias; Workneh, Netsanet; Mekonnen, Zeleke; Levecke, Bruno; Steinmann, Peter; Umulisa, Irenee; Alemu, Hailemaryam; Baeten, Benny; Engelen, Marc; Hu, Peter; Friedman, Andrew; Baseman, Alan; Mrus, Joseph
2017-12-01
This randomized, double-blind, placebo-controlled study evaluated the efficacy and safety of a new chewable, rapidly-disintegrating mebendazole (MBZ) 500 mg tablet for Ascaris lumbricoides and Trichuris trichiura infection treatment. Pediatric patients (1-15 years; N = 295; from Ethiopia and Rwanda) excreting A. lumbricoides and/or T. trichiura eggs were enrolled. The study had a screening phase (3 days), a double-blind treatment phase (DBP, 19 days), and an open-label phase (OLP, 7 days). Patients received MBZ or placebo on day 1 of DBP and open-label MBZ on day 19 ± 2 after stool sample collection. Cure rates (primary endpoint), defined as species-specific egg count of 0 at the end of DBP, were significantly higher in the MBZ group than placebo for A. lumbricoides (83.7% [72/86; 95% CI: 74.2%; 90.8%] versus 11.1% [9/81; 95% CI: 5.2%; 20.1%], P < 0.001) and for T. trichiura (33.9% [42/124; 95% CI: 25.6%; 42.9%] versus 7.6% [9/119; 95% CI: 3.5%; 13.9%], P < 0.001). Egg reduction rates (secondary endpoint) were significantly higher in the MBZ group than placebo for A. lumbricoides (97.9% [95% CI: 94.4; 99.9] versus 19.2% [95% CI: -5.9; 41.5]; P < 0.001) and T. trichiura (59.7% [95% CI: 33.9; 78.8] versus 10.5% [95% CI: -16.8; 32.9]; P = 0.003). Treatment-emergent adverse events (TEAEs) in MBZ group occurred in 6.3% (9/144) of patients during DBP and 2.5% (7/278) during OLP. No deaths, serious TEAEs, or TEAEs leading to discontinuations were reported. A 500 mg chewable MBZ tablet was more efficacious than placebo for the treatment of A. lumbricoides and T. trichiura infections in pediatric patients, and no safety concerns were identified.
Lulla, Rishi R; Goldman, Stewart; Yamada, Tohru; Beattie, Craig W; Bressler, Linda; Pacini, Michael; Pollack, Ian F; Fisher, Paul Graham; Packer, Roger J; Dunkel, Ira J; Dhall, Girish; Wu, Shengjie; Onar, Arzu; Boyett, James M; Fouladi, Maryam
2016-09-01
p53 is a promising target in human cancer. p28 is a cell-penetrating peptide that preferentially enters cancer cells and binds to both wild-type and mutant p53 protein, inhibiting COP1-mediated ubiquitination and proteasomal degradation. This results in increased levels of p53, which induces cell cycle arrest at G2/M. We conducted a phase I study to determine the maximum-tolerated dose (MTD) and describe the dose-limiting toxicities (DLTs) and pharmacokinetics (PKs) of p28 in children. Children aged 3-21 years with recurrent or progressive central nervous system tumors were eligible. Intravenous p28 was administered 3 times weekly for 4 consecutive weeks of a 6-week cycle at 4.16 mg/kg/dose (the adult recommended phase II dose) using a rolling-6 study design. Expression status of p53 was characterized by immunohistochemistry, and serum PK parameters were established on the second dose. Of the 18 eligible patients enrolled in the study, 12 completed the DLT monitoring period and were evaluable for toxicity. p28 was well-tolerated; 7 participants received ≥2 courses, and the most common adverse event attributed to the drug was transient grade 1 infusion-related reaction. PK analysis revealed a profile similar to adults; however, an increased area under the curve was observed in pediatric patients. High p53 expression in tumor cell nuclei was observed in 6 of 12 available tissue samples. There were no objective responses; 2 participants remained stable on the study for >4 cycles. This phase I study demonstrated that p28 is well-tolerated in children with recurrent CNS malignancies at the adult recommended phase II dose. © The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Raley, Jessica; Meenakshi, Rani; Dent, Daniel; Willis, Ross; Lawson, Karla; Duzinski, Sarah
Fatal errors due to miscommunication among members of trauma teams are 2 to 4 times more likely to occur than in other medical teams, yet most trauma team members do not receive communication effectiveness training. A needs assessment was conducted to examine trauma team members' miscommunication experiences and research scientists' evaluations of live trauma activations. The purpose of this study is to demonstrate that communication training is necessary and highlight specific team communication competencies that trauma teams should learn to improve communication during activations. Data were collected in 2 phases. Phase 1 required participants to complete a series of surveys. Phase 2 included live observations and assessments of pediatric trauma activations using the assessment of pediatric resuscitation team assessments (APRC-TA) and assessment of pediatric resuscitation leader assessments (APRC-LA). Data were collected at a southwestern pediatric hospital. Trauma team members and leaders completed surveys at a meeting and were observed while conducting activations in the trauma bay. Trained research scientists and clinical staff used the APRC-TA and APRC-LA to measure trauma teams' medical performance and communication effectiveness. The sample included 29 healthcare providers who regularly participate in trauma activations. Additionally, 12 live trauma activations were assessed monday to friday from 8am to 5pm. Team members indicated that communication training should focus on offering assistance, delegating duties, accepting feedback, and controlling emotional expressions. Communication scores were not significantly different from medical performance scores. None of the teams were coded as effective medical performance and ineffective team communication and only 1 team was labeled as ineffective leader communication and effective medical performance. Communication training may be necessary for trauma teams and offer a deeper understanding of the communication competencies that should be addressed. The APRC-TA and APRC-LA both include team communication competencies that could be used as a guide to design training for trauma team members and leaders. Researchers should also continue to examine recommendations for improved team and leader communication during activations using in-depth interviews and focus groups. Copyright © 2016 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.
Ren, Bingbing; Tan, Hwei Ling; Nguyen, Thi Thuy Trang; Sayed, Ahmed Mahmoud Mohammed; Li, Ying; Mok, Yu-Keung; Yang, Henry; Chen, Ee Sin
2018-01-09
Heterochromatin silencing is critical for genomic integrity and cell survival. It is orchestrated by chromodomain (CD)-containing proteins that bind to methylated histone H3 lysine 9 (H3K9me), a hallmark of heterochromatin. Here, we show that phosphorylation of tyrosine 41 (H3Y41p)-a novel histone H3 modification-participates in the regulation of heterochromatin in fission yeast. We show that a loss-of-function mutant of H3Y41 can suppress heterochromatin de-silencing in the centromere and subtelomere repeat regions, suggesting a de-silencing role for H3Y41p on heterochromatin. Furthermore, we show both in vitro and in vivo that H3Y41p differentially regulates two CD-containing proteins without the change in the level of H3K9 methylation: it promotes the binding of Chp1 to histone H3 and the exclusion of Swi6. H3Y41p is preferentially enriched on centromeric heterochromatin during M- to early S phase, which coincides with the localization switch of Swi6/Chp1. The loss-of-function H3Y41 mutant could suppress the hypersensitivity of the RNAi mutants towards hydroxyurea (HU), which arrests replication in S phase. Overall, we describe H3Y41p as a novel histone modification that differentially regulates heterochromatin silencing in fission yeast via the binding of CD-containing proteins. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.
Halicka, Dorota; Zhao, Hong; Li, Jiangwei; Garcia, Jorge; Podhorecka, Monika; Darzynkiewicz, Zbigniew
2017-01-01
Cell synchronization is often achieved by transient inhibition of DNA replication. When cultured in the presence of such inhibitors as hydroxyurea, aphidicolin or excess of thymidine the cells that become arrested at the entrance to S-phase upon release from the block initiate progression through S then G 2 and M. However, exposure to these inhibitors at concentrations commonly used to synchronize cells leads to activation of ATR and ATM protein kinases as well as phosphorylation of Ser139 of histone H2AX. This observation of DNA damage signaling implies that synchronization of cells by these inhibitors is inducing replication stress. Thus, a caution should be exercised while interpreting data obtained with use of cells synchronized this way since they do not represent unperturbed cell populations in a natural metabolic state. This chapter critically outlines virtues and vices of most cell synchronization methods. It also presents the protocol describing an assessment of phosphorylation of Ser139 on H2AX and activation of ATM in cells treated with aphidicolin, as a demonstrative of one of several DNA replication inhibitors that are being used for cell synchronization. Phosphorylation of Ser139H2AX and Ser1981ATM in individual cells is detected immunocytochemically with phospho-specific Abs and intensity of immunofluorescence is measured by flow cytometry. Concurrent measurement of cellular DNA content followed by multiparameter analysis allows one to correlate the extent of phosphorylation of these proteins in response to aphidicolin with the cell cycle phase.
Toupin April, Karine; Stinson, Jennifer; Boon, Heather; Duffy, Ciarán M.; Huber, Adam M.; Gibbon, Michele; Descarreaux, Martin; Spiegel, Lynn; Vohra, Sunita; Tugwell, Peter
2016-01-01
Objective Complementary and alternative medicine (CAM) is commonly used by children with juvenile idiopathic arthritis (JIA), yet no validated questionnaires assess that use. The objective of this study was to develop child self- and parent proxy-report questionnaires assessing CAM use and to determine the face and content validity of the “Which Health Approaches and Treatments are you using?” (WHAT) questionnaires in pediatric rheumatology. Methods A sequential phased mixed methods approach was used to develop the questionnaires. A Delphi Survey of 126 experts followed by an interdisciplinary consensus conference of 14 stakeholders in CAM, general pediatrics and pediatric rheumatology was held to develop consensus on the content of the questionnaires using a nominal group technique. To determine face and content validity of the questionnaires, two groups, including (a) a purposive sample of 22 children with JIA 8 to 18 years and their parents from the Children’s Hospital of Eastern Ontario and the Hospital for Sick Children, and (b) 21 Canadian pediatric rheumatology experts, participated in interviews. Participants were independently asked about the goal, understandability and comprehensiveness of the WHAT questionnaires, as well as the relevance of items. Results Consensus was reached on 17 items of the WHAT questionnaires. The domains found to be relevant were child’s CAM use, factors associated with CAM use, perceived impact of CAM use, and communication about CAM. A total of 15 items in the parent proxy-report questionnaire and 13 items in the child report questionnaire showed adequate content validity. Conclusions Consensus was reached by experts on the content of a pediatric CAM questionnaire. Face and content validity testing and modifications made to the WHAT questionnaires have helped ensure adequate preliminary validity for use in pediatric rheumatology. This constitutes the basis for further testing of these questionnaires in pediatric rheumatology and for adaptation to other chronic diseases. PMID:26964088
Toupin April, Karine; Stinson, Jennifer; Boon, Heather; Duffy, Ciarán M; Huber, Adam M; Gibbon, Michele; Descarreaux, Martin; Spiegel, Lynn; Vohra, Sunita; Tugwell, Peter
2016-01-01
Complementary and alternative medicine (CAM) is commonly used by children with juvenile idiopathic arthritis (JIA), yet no validated questionnaires assess that use. The objective of this study was to develop child self- and parent proxy-report questionnaires assessing CAM use and to determine the face and content validity of the "Which Health Approaches and Treatments are you using?" (WHAT) questionnaires in pediatric rheumatology. A sequential phased mixed methods approach was used to develop the questionnaires. A Delphi Survey of 126 experts followed by an interdisciplinary consensus conference of 14 stakeholders in CAM, general pediatrics and pediatric rheumatology was held to develop consensus on the content of the questionnaires using a nominal group technique. To determine face and content validity of the questionnaires, two groups, including (a) a purposive sample of 22 children with JIA 8 to 18 years and their parents from the Children's Hospital of Eastern Ontario and the Hospital for Sick Children, and (b) 21 Canadian pediatric rheumatology experts, participated in interviews. Participants were independently asked about the goal, understandability and comprehensiveness of the WHAT questionnaires, as well as the relevance of items. Consensus was reached on 17 items of the WHAT questionnaires. The domains found to be relevant were child's CAM use, factors associated with CAM use, perceived impact of CAM use, and communication about CAM. A total of 15 items in the parent proxy-report questionnaire and 13 items in the child report questionnaire showed adequate content validity. Consensus was reached by experts on the content of a pediatric CAM questionnaire. Face and content validity testing and modifications made to the WHAT questionnaires have helped ensure adequate preliminary validity for use in pediatric rheumatology. This constitutes the basis for further testing of these questionnaires in pediatric rheumatology and for adaptation to other chronic diseases.
Using a Multimedia Presentation to Enhance Informed Consent in a Pediatric Emergency Department.
Spencer, Sandra P; Stoner, Michael J; Kelleher, Kelly; Cohen, Daniel M
2015-08-01
Informed consent is an ethical process for ensuring patient autonomy. Multimedia presentations (MMPs) often aid the informed consent process for research studies. Thus, it follows that MMPs would improve informed consent in clinical settings. The aim of this study was to determine if an MMP for the informed consent process for ketamine sedation improves parental satisfaction and comprehension as compared with standard practice. This 2-phase study compared 2 methods of informed consent for ketamine sedation of pediatric patients. Phase 1 was a randomized, prospective study that compared the standard verbal consent to an MMP. Phase 2 implemented the MMP into daily work flow to validate the previous year's results. Parents completed a survey evaluating their satisfaction of the informed consent process and assessing their knowledge of ketamine sedation. Primary outcome measures were parental overall satisfaction with the informed consent process and knowledge of ketamine sedation. One hundred eighty-four families from a free-standing, urban, tertiary pediatric emergency department with over 85,000 annual visits were enrolled. Different demographics were not associated with a preference for the MMP or improved scores on the content quiz. Intervention families were more likely "to feel involved in the decision to use ketamine" and to understand that "they had the right to refuse the ketamine" as compared with control families. The intervention group scored significantly higher overall on the content section than the control group. Implementation and intervention families responded similarly to all survey sections. Multimedia presentation improves parental understanding of ketamine sedation, whereas parental satisfaction with the informed consent process remains unchanged. Use of MMP in the emergency department for informed consent shows potential for both patients and providers.
Rosenberg, Rebecca E; Devins, Lea; Geraghty, Gail; Bock, Steven; Dugan, Christina A; Transou, Marjorie; Phillips, Michael; Lighter-Fisher, Jennifer
2015-10-01
Central venous catheters are crucial devices in the care of hospitalized children, both in and out of critical care units, but the concomitant risk of central line-associated bloodstream infection (CLABSI) affects 15,000 Americans annually. In 2012, CLABSI rates varied among units from 6.8/1,000 to 1.0/1,000 in a 109-bed children's service within NYU Langone Medical Center (NYULMC; New York City), a 1,069-bed tertiary care academic medical center. In response to variation in central line-related practices and infection prevention rates, a CLABSI Prevention Core Team began an effort to standardize central venous catheter (CVC) care across all pediatric units (ICU and non-ICU). Momentum in this quality improvement (QI) work was interrupted when Superstorm Sandy shuttered the flagship hospital, but the relatively decreased clinical load provided a "downtime" opportunity to address CLABSI prevention. The first phase of the collaborative effort, Booster 1, Planning/Initial Phase: Development of a Pediatric Central Venous Catheter Working Group, was followed by Booster 2, Maintenance/Sustaining Phase: Transitioning for Sustainability and Adopting Model for Improvement. Data in the subsequent 21 months after the temporary closure of the facility (January 2013-September 2014) showed an increase in maintenance bundle reliability. The inpatient CLABSI rate for patients<18 years decreased from an annual rate of 2.7/1,000 line days (2012) to 0.6/1,000 line days (2013) to 0.5/1,000 line days as of August 2014. There was a decrease in pediatric CLABSI events and no significant change in line days. Key elements contributing to initial success with evolving QI capacity and resources were likely multi-factorial, including staff and leadership engagement, culture change, consistent guidelines, and accountability by individuals and by our multidisciplinary core team.
Kobayashi, Kyoko; Nakagami-Yamaguchi, Etsuko; Hayakawa, Akira; Adachi, Souichi; Hara, Junichi; Tokimasa, Sadao; Ohta, Hideaki; Hashii, Yoshiko; Rikiishi, Takeshi; Sawada, Machiko; Kuriyama, Kikuko; Kohdera, Urara; Kamibeppu, Kiyoko; Kawasaki, Hirohide; Oda, Megumi; Hori, Hiroki
2017-02-01
Quality of life (QOL) as a treatment outcome has not yet been evaluated among patients receiving a specific treatment regimen by treatment phase in a consistent manner. This exploratory cross-sectional study evaluated the QOL of children with acute lymphoblastic leukemia (ALL) receiving one of the most popular treatment regimens in Japan (Japan Association of Childhood Leukemia Study ALL-02 revised protocol). Children aged 5-18 years with newly diagnosed B-cell precursor ALL were included. The Pediatric Quality of Life Inventory ™ 4.0 Generic Core Scales (PedsQL-J) were completed by children with ALL and their siblings, as well as by age- and sex-matched healthy controls. PedsQL Cancer Module (PedsQL-C) scores were also collected from children with ALL. QOL in children with ALL of the consolidation phase group was significantly decreased compared with that of healthy controls, except in the area of emotional functioning. Regarding the maintenance phase group, QOL impairment was noted in the physical and school functioning, but no differences were noted in social functioning. The off-treatment group had a large effect size only for physical functioning, and the social functioning score was even better in children with ALL than in matched controls. QOL of children with ALL differed with treatment phase. Effect size varied with function and treatment phase. QOL may change with the progression of treatment, and the timing of these changes varied according to function and problem. © 2016 Japan Pediatric Society.
Yamada, Janet; Potestio, Melissa L; Cave, Andrew J; Sharpe, Heather; Johnson, David W; Patey, Andrea M; Presseau, Justin; Grimshaw, Jeremy M
2017-12-20
This study aimed to apply a theory-based approach to identify barriers and enablers to implementing the Alberta Primary Care Asthma Pediatric Pathway (PCAPP) into clinical practice. Phase 1 included an assessment of assumptions underlying the intervention from the perspectives of the developers. Phase 2 determined the perceived barriers and enablers for: 1) primary care physicians' prescribing practices, 2) allied health care professionals' provision of asthma education to parents, and 3) children and parents' adherence to their treatment plans. Interviews were conducted with 35 individuals who reside in Alberta, Canada. Phase 1 included three developers. Phase 2 included 11 primary care physicians, 10 allied health care professionals, and 11 parents of children with asthma. Phase 2 interviews were based on the 14 domains of the Theoretical Domains Framework (TDF). Transcribed interviews were analyzed using a directed content analysis. Key assumptions by the developers about the intervention, and beliefs by others about the barriers and enablers of the targeted behaviors were identified. Eight TDF domains mapped onto the assumptions of the pathway as described by the intervention developers. Interviews with health care professionals and parents identified nine TDF domains that influenced the targeted behaviors: knowledge, skills, beliefs about capabilities, social/professional role and identity, beliefs about consequences, environmental context and resources, behavioral regulation, social influences, and emotions. Barriers and enablers perceived by health care professionals and parents that influenced asthma management will inform the optimization of the PCAPP prior to its evaluation.
Wietecha, Linda A.; Wang, Shufang; Buchanan, Andrew S.; Kelsey, Douglas K.
2014-01-01
Abstract Objective: This meta-analysis examined suicide-related events in the acute phases of double-blind, placebo-controlled atomoxetine trials in pediatric and adult patients with attention-deficit/hyperactivity disorder (ADHD). Methods: A total of 3883 pediatric and 3365 adult patients were included. Potential events were identified from the adverse events database using a text-string search. Mantel–Haenszel risk ratios (MHRR) were calculated for potential suicide-related events categorized according to United States Food and Drug Administration defined codes. Results: In this data set, no completed suicides were reported in the pediatric or adult populations. One pediatric (attempted suicide) (and no adult patient events) was categorized as suicidal behavior in the atomoxetine group. The frequency of combined suicidal behavior or ideation with atomoxetine treatment was 0.37% in pediatric patients (vs. 0.07% with placebo) and 0.11% in adults (vs. 0.12% with placebo) and the risk compared with placebo was not statistically significant (MHRR=1.57; p=0.42 and MHRR=0.96; p=0.96, respectively). In pediatric patients, suicidal ideation only was reported more frequently compared with placebo (MHRR=1.63; p=0.41). Conclusions: Overall in this data set, no completed suicides and 1 pediatric patient suicidal behavior event were reported in atomoxetine-treated pediatric and adult patients. Suicidal ideation was uncommon among atomoxetine-treated pediatric and adult patients, although it was reported more frequently in atomoxetine-treated pediatric patients compared with placebo; the reporting rate difference was not statistically significant. The MHRR of suicidal ideation was consistent with a previous meta-analysis of similar design. There was no evidence of increased risk for suicidal behavior in atomoxetine-treated pediatric or adult patients. Clinical trial registration information: http://www.clinicaltrials.gov. The data reported are from an analysis of 23 pediatric and 9 adult clinical trials completed between 1998 and 2011. Ten pediatric (Studies HFBD, HFBK, LYAC, LYAS, LYAT, LYAW, LYAX, LYBG, LYBI, and LYBP) and two adult trials (Studies LYAA and LYAO) were conducted before the requirement to post trials at initiation (ongoing as of July 1, 2005) and, therefore, do not have a registration number. The registration numbers for the 13 pediatric trials meeting this requirement are: NCT00191698 (LYBX), NCT00486122 (LYCC), NCT00386581 (LYCZ), NCT00485459 (S010), NCT00191542 (LY15), NCT00191295 (LYBC), NCT00191906 (LYCK), NCT00192023 (LYCY), NCT00191945 (LYDM), NCT00546910 (LYDV), NCT00406354 (LYDW), NCT00380692 (S017), and NCT00607919 (LYEB). For the seven adult trials, the registration numbers are: NCT00190931 (LYBV), NCT00190957 (LYBY), NCT00190736 (LYCU), NCT00190775 (LYCW), NCT00190879 (LYDQ), NCT00510276 (LYDZ), and NCT00962104 (LYEE). PMID:25019647
Kim, Michael E; Orth, Robert C; Fallon, Sara C; Lopez, Monica E; Brandt, Mary L; Zhang, Wei; Bisset, George S
2015-04-01
Despite a recent focus on the preferential use of ultrasound over CT for pediatric appendicitis, most children transferred from community hospitals still undergo diagnostic CT scans. The purpose of this study was to evaluate CT techniques performed for children with acute appendicitis at nonpediatric treatment centers. All patients treated for acute appendicitis at our tertiary-care pediatric hospital from July 1, 2011, through June 30, 2012, were identified. Patient demographics, imaging modality used to diagnoses appendicitis (CT or ultrasound), location (home or referral institution), and CT technique parameters were collected. The estimated mean organ radiation dose, number of imaging phases, and use of contrast media were evaluated at home and referral institutions. During the study period, 1215 patients underwent appendectomies after imaging, with 442 (36.4%) imaged at referral facilities. Most referral patients received a diagnosis by CT (n=384, 87%), compared with 73 of 773 (9.4%) who received a diagnosis by CT at the home institution. The estimated mean (±SD) organ radiation dose was not statistically significantly different between home and referral institutions (13.5±7.3 vs 12.9±6.4 mGy; p=0.58) for single-phase examinations. Of 384 referral patients, 344 had images available for review. In total, 40% (138/344) of patients from referral centers were imaged with suboptimal CT techniques: 50 delayed phase only, 52 dual phase (eight of which were imaged twice in delayed phase), eight triple phase, and 36 without IV contrast agent. CT parameters and radiation doses from single-phase examinations in children with appendicitis were similar at nonpediatric treatment centers and a tertiary care children's hospital. Future educational outreach should focus on optimizing other technical parameters.
Flood, Emuella; Silberg, Debra G; Romero, Beverly; Beusterien, Kathleen; Erder, M Haim; Cuffari, Carmen
2017-09-25
The purpose of this study is to develop patient-reported (PRO) and observer-reported (ObsRO) outcome measures of ulcerative colitis (UC) signs/symptoms in children aged 5-17 with mild/moderate UC. The daily ulcerative colitis signs and symptoms scale (DUCS) was developed in two phases. Phase I involved concept elicitation interviews with patients and healthcare providers, review of website posts and item generation. Phase II involved cognitive debriefing and assessment of usability and feasibility of the eDiaries. Participants were recruited from five US clinical sites, a research recruitment agency, and internet advertising. Thematic and content analysis was performed to identify concepts from Phase I. The Phase II cognitive debriefing interviews were analyzed iteratively to identify problems with clarity and relevance of eDiary content. The US Food and Drug Administration (FDA) also reviewed and provided feedback on the eDiaries. Phase I included 32 participants (22 remission; 10 active disease). Phase II included 38 participants (22 remission; 16 active disease). A core set of seven signs and symptoms emerged that were reported by at least 30% of the patients interviewed: abdominal pain, blood in stool, frequent stools, diarrhea, stool urgency, nighttime stools, and tiredness. Participant input influenced changes such as refinement of item wording, revision of graphics, and selection of response scales. Revisions suggested by FDA included simplifying the response scale and adding questions to capture symptoms during sleeping hours. The findings of instrument development suggest that the DUCS PRO and ObsRO eDiaries are content-valid instruments for capturing the daily signs and symptoms of pediatric patients with mild to moderate UC in a clinical trial setting.
Hydroxyurea enhances SMN2 gene expression through nitric oxide release.
Xu, Cheng; Chen, Xin; Grzeschik, Susanna M; Ganta, Madhuri; Wang, Ching H
2011-02-01
Small molecules that increase full-length survivor motor neuron (SMN) gene transcript are promising therapeutic candidates for spinal muscular atrophy (SMA). Hydroxyurea (HU) has recently been shown to increase full-length SMN transcript in cultured lymphocytes from patients with SMA. We investigate the mechanism by which HU enhances full-length SMN2 gene expression in SMA lymphocytes. Nitric oxide (NO) is a major intracellular metabolite of HU. We test whether NO donors can themselves enhance full-length SMN2 expression. Eighteen cell lines (five type I, five type II, six type III SMA, and two non-SMA controls) were treated with or without NO donors for 48 h. SMA cells treated with HU and three NO donors: two long-acting donors, Deta-NONOate and S-nitrosoglutathione, and one short-acting donor, 3-ethyl-3-(ethylaminoethyl)-1-hydroxy-2-oxo-1-triazene, resulted in significant increase in full-length SMN2 mRNA. These effects were abolished by co-treatment with an NO scavenger 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide. One short-acting NO donor, S-nitroso-N-acetyl-DL-penicillamine, failed to show significant effect on full-length SMN2 expression, possibly due to high degree of cytotoxicity. These results were observed using both densitometry and quantitative PCR methods. We conclude that HU enhances SMN2 expression through the release of NO. NO donors may themselves be considered as new therapeutic candidates for SMA.
Azouani, R; Tieng, S; Chhor, K; Bocquet, J-F; Eloy, P; Gaigneaux, E M; Klementiev, K; Kanaev, A V
2010-10-07
We report an original method of preparation of OCN-doped TiO(2) for photocatalysis in the visible spectral range. The preparation is achieved by a sol-gel route using titanium tetraisopropoxide precursor. Special attention was paid to fluid micromixing, which enables homogeneous reaction conditions in the reactor bulk and monodispersity of the produced clusters/nanoparticles. The dopant hydroxyurea (HyU, CH(4)N(2)O(2)) is injected into the reactive fluid at the nucleation stage, which lasts tens of milliseconds. The doping results in a strong yellow coloration of the nanocolloids due to the absorption band in the spectral range 380-550 nm and accelerates the aggregation kinetics of both nuclei at the induction stage and sub-nuclei units (clusters) at the nucleation stage. FTIR, Raman and UV-visible absorption analyses show the formation of a stable HyU-TiO(2) complex. EXAFS spectra indicate no appreciable changes of the first-shell Ti atom environment. The doping agent takes available surface sites of TiO(2) clusters/nanoparticles attaining ∼10% molar loading. The reaction kinetics then accelerates due to a longer collisional lifetime between nanoparticles induced by the formation of a weak [double bond, length as m-dash]OTi bond. The OCN-group bonding to titanium atoms produces a weakening of the C[double bond, length as m-dash]O double bond and a strengthening of the C-N and N-O bonds.
Clinical Course of Two Children with Unstable Hemoglobins: The Effect of Hydroxyurea Therapy.
Loovers, Harriët M; Tamminga, Nienke; Mulder, André B; Tamminga, Rienk Y J
2016-09-01
Case reports on the effect of hydroxyurea (HU) therapy for unstable hemoglobins (Hbs) are sparse; only three adult cases have been reported. We report for the first time on the effect of HU therapy in children carrying unstable Hbs. The first case concerns a female child with a familial history of chronic hemolytic anemia. She was diagnosed with Hb Volga (HBB: c.83C>A) at the age of 7 months. At age 6, treatment options were reconsidered due to increasing fatigue and decreasing Hb concentration. The second case also concerns a female child with chronic hemolytic anemia and icterus since the age of 5. She was diagnosed with Hb Köln (HBB: c.295G>A) at the age of 9. At age 10, treatment options were reconsidered due to decreased general condition and poor school performance. Both children were started on HU therapy. The child with Hb Volga showed reduced clinical symptoms and increased average Hb concentrations. She has been on HU therapy for over 7 years at preparation of this manuscript. The child with Hb Köln showed decreasing Hb concentrations upon start of therapy; clinical symptoms did not improve. Therapy was discontinued after 3½ months. The Hb Volga case report suggests that HU therapy could improve clinical symptoms in some patients with unstable Hbs. Based on these and previously published cases, it was speculated that response can be predicted by the percentage of Hb F and reticulocyte counts.
Hojjati, Mohammad T; Azarkeivan, Azita; Pourfathollah, Ali A; Amirizadeh, Naser
2017-03-01
Drug induction of Hb F seems to be an ideal therapy for patients with hemoglobin (Hb) disorders, and many efforts have been made to reveal the mechanism behind it. Thus, we examined in vivo expression of some microRNAs (miRNAs) that are thought to be involved in this process. Among β-thalassemia (β-thal) patients who were undergoing hydroxyurea (HU) therapy in the past 3 months and five healthy individuals, five responders and five non-responders, were also included in the study. Erythroid progenitors were isolated by magnetic activated cell sorting (MACS) and miRNA expression analyzed using reverse transcription-polymerase chain reaction (RT-PCR). We showed that γ-globin, miR-210 and miR-486-3p had higher levels in the responders than the non-responders group. Moreover, miR-150 and miR-320 had higher levels in the healthy group than both non-responders and responders groups, but the expression of miR-96 did not show any significant difference between the study groups. To the best of our knowledge, this is the first study proposing that 'induction of cellular hypoxic condition by Hb F inducing agents' could be the milestone of possible mechanisms that explain why responders are able to reactivate γ-globin genes and subsequently, more production of Hb F, in response to these agents in comparison to non-responders. However, further investigations need to be performed to verify this hypothesis.
Rybaczek, Dorota; Musiałek, Marcelina Weronika; Balcerczyk, Aneta
2015-01-01
We have demonstrated that the activation of apoptosis-like programmed cell death (AL-PCD) was a secondary result of caffeine (CF) induced premature chromosome condensation (PCC) in hydroxyurea-synchronized Vicia faba root meristem cells. Initiation of the apoptotic-like cell degradation pathway seemed to be the result of DNA damage generated by treatment with hydroxyurea (HU) [double-stranded breaks (DSBs) mostly] and co-treatment with HU/CF [single-stranded breaks (SSBs) mainly]. A single chromosome comet assay was successfully used to study different types of DNA damage (neutral variant–DSBs versus alkaline–DSBs or SSBs). The immunocytochemical detection of H2AXS139Ph and PARP-2 were used as markers for DSBs and SSBs, respectively. Acridine orange and ethidium bromide (AO/EB) were applied for quantitative immunofluorescence measurements of dead, dying and living cells. Apoptotic-type DNA fragmentation and positive TUNEL reaction finally proved that CF triggers AL-PCD in stressed V. faba root meristem cells. In addition, the results obtained under transmission electron microscopy (TEM) further revealed apoptotic-like features at the ultrastructural level of PCC-type cells: (i) extensive vacuolization; (ii) abnormal chromatin condensation, its marginalization and concomitant degradation; (iii) formation of autophagy-like vesicles (iv) protoplast shrinkage (v) fragmentation of cell nuclei and (vi) extensive degeneration of the cells. The results obtained have been discussed with respect to the vacuolar/autolytic type of plant-specific AL-PCD. PMID:26545248
Koh, Katsuyoshi; Ogawa, Chitose; Okamoto, Yasuhiro; Kudo, Kazuko; Inagaki, Jiro; Morimoto, Tsuyoshi; Mizukami, Hideya; Ecstein-Fraisse, Evelyne; Kikuta, Atsushi
2016-08-01
A phase 1 study was conducted to evaluate the safety, pharmacokinetics (PK), efficacy and pharmacogenetic characteristics of clofarabine in seven Japanese pediatric patients with relapsed/refractory acute lymphoblastic leukemia (ALL). Patients in Cohort 1 received clofarabine 30 mg/m(2)/day for 5 days, followed by 52 mg/m(2)/day for 5 days in subsequent cycles. Cohort 2 patients were consistently treated with 52 mg/m(2)/day for 5 days. No more than six cycles were performed. Every patient had at least one ≥Grade 3 adverse event (AE). AEs (≥Grade 3) related to clofarabine were anaemia, neutropenia, febrile neutropenia, thrombocytopenia, alanine aminotransferase increased, aspartate aminotransferase increased, haemoglobin decreased, and platelet (PLT) count decreased. C max and AUC of clofarabine increased in a dose-dependent fashion, but its elimination half-life (T 1/2) did not appear to be dependent on dose or duration of treatment. Clofarabine at 52 mg/m(2)/day shows similarly tolerable safety and PK profiles compared to those in previous studies. No complete remission (CR), CR without PLT recovery, or partial remission was observed. Since clofarabine is already used as a key drug for relapsed/refractory ALL patients in many countries, the efficacy of clofarabine in Japanese pediatric patients should be evaluated in larger study including more patients, such as by post-marketing surveillance.
Rosenthal, Victor D; Ramachandran, Bala; Dueñas, Lourdes; Alvarez-Moreno, Carlos; Navoa-Ng, J A; Armas-Ruiz, Alberto; Ersoz, Gulden; Matta-Cortés, Lorena; Pawar, Mandakini; Nevzat-Yalcin, Ata; Rodríguez-Ferrer, Marena; Bran de Casares, Ana Concepción; Linares, Claudia; Villanueva, Victoria D; Campuzano, Roberto; Kaya, Ali; Rendon-Campo, Luis Fernando; Gupta, Amit; Turhan, Ozge; Barahona-Guzmán, Nayide; de Jesús-Machuca, Lilian; Tolentino, María Corazon V; Mena-Brito, Jorge; Kuyucu, Necdet; Astudillo, Yamileth; Saini, Narinder; Gunay, Nurgul; Sarmiento-Villa, Guillermo; Gumus, Eylul; Lagares-Guzmán, Alfredo; Dursun, Oguz
2012-07-01
A before-after prospective surveillance study to assess the impact of a multidimensional infection control approach for the reduction of catheter-associated urinary tract infection (CAUTI) rates. Pediatric intensive care units (PICUs) of hospital members of the International Nosocomial Infection Control Consortium (INICC) from 10 cities of the following 6 developing countries: Colombia, El Salvador, India, Mexico, Philippines, and Turkey. PICU inpatients. We performed a prospective active surveillance to determine rates of CAUTI among 3,877 patients hospitalized in 10 PICUs for a total of 27,345 bed-days. The study was divided into a baseline period (phase 1) and an intervention period (phase 2). In phase 1, surveillance was performed without the implementation of the multidimensional approach. In phase 2, we implemented a multidimensional infection control approach that included outcome surveillance, process surveillance, feedback on CAUTI rates, feedback on performance, education, and a bundle of preventive measures. The rates of CAUTI obtained in phase 1 were compared with the rates obtained in phase 2, after interventions were implemented. During the study period, we recorded 8,513 urinary catheter (UC) days, including 1,513 UC-days in phase 1 and 7,000 UC-days in phase 2. In phase 1, the CAUTI rate was 5.9 cases per 1,000 UC-days, and in phase 2, after implementing the multidimensional infection control approach for CAUTI prevention, the rate of CAUTI decreased to 2.6 cases per 1,000 UC-days (relative risk, 0.43 [95% confidence interval, 0.21-1.0]), indicating a rate reduction of 57%. Our findings demonstrated that implementing a multidimensional infection control approach is associated with a significant reduction in the CAUTI rate of PICUs in developing countries.
'Shovel-Ready' applications of stem cell advances for pediatric heart disease.
Files, Matthew D; Boucek, Robert J
2012-10-01
The past decade has seen remarkable advances in the field of stem cell biology. Many new technologies and applications are passing the translational phase and likely will soon be relevant for the clinical pediatric cardiologist. This review will focus on two advances in basic science that are now translating into clinical trials. The first advance is the recognition, characterization, and recent therapeutic application of resident cardiac progenitor cells (CPCs). Early results of adult trials and scattered case reports in pediatric patients support expanding CPC-based trials for end-stage heart failure in pediatric patients. The relative abundance of CPCs in the neonate and young child offers greater potential benefits in heart failure treatment than has been realized to date. The second advance is the technology of induced pluripotent stem cells (iPSCs), which reprograms differentiated somatic cells to an undifferentiated embryonic-like state. When iPSCs are differentiated into cardiomyocytes, they model a patient's specific disease, test pharmaceuticals, and potentially provide an autologous source for cell-based therapy. The therapeutic recruitment and/or replacement of CPCs has potential for enhancing cardiac repair and regeneration in children with heart failure. Use of iPSCs to model heart disease holds great potential to gain new insights into diagnosis, pathophysiology, and disease-specific management for genetic-based cardiovascular diseases that are prevalent in pediatric patients.
Eisen, Sarajane L; Ulrich, Roger S; Shepley, Mardelle M; Varni, James W; Sherman, Sandra
2008-09-01
Art is assumed to possess therapeutic benefits of healing for children, as part of patient-focused design in health care. Since the psychological and physiological well-being of children in health care settings is extremely important in contributing to the healing process, it is vitally important to identify what type of art supports stress reduction. Based on adult studies, nature art was anticipated to be the most preferred and to have stress-reducing effects on pediatric patients. Nature art refers to art images dominated by natural vegetation, flowers or water. The objective of this study was to investigate what type of art image children prefer, and what type of art image has potentially stress-reducing effects on children in hospitals. This study used a three-phase, multi-method approach with children aged 5-17 years: a focus group study (129 participants), a randomized study (48 participants), and a quasi-experimental study design (48 participants). Findings were evaluated from three phases.
Mackay, Alan; Burford, Anna; Molinari, Valeria; Jones, David T W; Izquierdo, Elisa; Brouwer-Visser, Jurriaan; Giangaspero, Felice; Haberler, Christine; Pietsch, Torsten; Jacques, Thomas S; Figarella-Branger, Dominique; Rodriguez, Daniel; Morgan, Paul S; Raman, Pichai; Waanders, Angela J; Resnick, Adam C; Massimino, Maura; Garrè, Maria Luisa; Smith, Helen; Capper, David; Pfister, Stefan M; Würdinger, Thomas; Tam, Rachel; Garcia, Josep; Thakur, Meghna Das; Vassal, Gilles; Grill, Jacques; Jaspan, Tim; Varlet, Pascale; Jones, Chris
2018-05-14
The HERBY trial was a phase II open-label, randomized, multicenter trial evaluating bevacizumab (BEV) in addition to temozolomide/radiotherapy in patients with newly diagnosed non-brainstem high-grade glioma (HGG) between the ages of 3 and 18 years. We carried out comprehensive molecular analysis integrated with pathology, radiology, and immune profiling. In post-hoc subgroup analysis, hypermutator tumors (mismatch repair deficiency and somatic POLE/POLD1 mutations) and those biologically resembling pleomorphic xanthoastrocytoma ([PXA]-like, driven by BRAF_V600E or NF1 mutation) had significantly more CD8 + tumor-infiltrating lymphocytes, and longer survival with the addition of BEV. Histone H3 subgroups (hemispheric G34R/V and midline K27M) had a worse outcome and were immune cold. Future clinical trials will need to take into account the diversity represented by the term "HGG" in the pediatric population. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.
Pediatric Scleroderma –Systemic and Localized Forms
Torok, Kathryn S.
2012-01-01
Synopsis statement Pediatric scleroderma includes two major groups of clinical entities, systemic sclerosis (SSc) and localized scleroderma (LS). Although both share a common pathophysiology, with an initial inflammatory phase associated with endothelial activation, and a later fibrotic phase evidenced by collagenization of tissue and appreciable skin thickness, their clinical manifestations differ. LS is typically confined to the skin and underlying subcutis, and though not fatal like SSc, up to a quarter of the patients may have extracutaneous disease manifestations, such as arthritis and uveitis. While any organ may be affected in SSc, vascular (Raynaud’s phenomenon), cutaneous (skin thickening), GI, pulmonary and musculoskeletal involvement are most commonly seen in children. Auto-antibody profiles in childhood onset SSc can assist in predicting internal organ involvement. Treatment for both forms of scleroderma targets the active inflammatory stage and halts disease progression; however, progress still needs to be made towards the development of a more effective anti-fibrotic therapy to help reverse disease damage. PMID:22560576
Kang, Min H.; Smith, Malcolm A.; Morton, Christopher L.; Keshelava, Nino; Houghton, Peter J.; Reynolds, C. Patrick
2010-01-01
Background The National Cancer Institute (NCI) has established the Pediatric Preclinical Testing Program (PPTP) for testing drugs against in vitro and in vivo childhood cancer models to aid in the prioritization of drugs considered for early phase pediatric clinical trials. Procedures In vitro cytotoxicity testing employs a semi-automated fluorescence-based digital imaging cytotoxicity assay (DIMSCAN) that has a 4-log dynamic range of detection. Curve fitting of the fractional survival data of the cell lines in response to various concentrations of the agents was used to calculate relative IC50, absolute IC50, and Ymin values The panel of 23 pediatric cancer cell lines included leukemia (n=6), lymphoma (n=2), rhabdomyosarcoma (n=4), brain tumors (n=3), Ewing family of tumors (EFT, n=4), and neuroblastoma (n=4). The doubling times obtained using DIMSCAN were incorporated into data analyses to estimate the relationship between input cell numbers and final cell number. Results We report in vitro activity data for three drugs (vincristine, melphalan, and etoposide) that are commonly used for pediatric cancer and for the mTOR inhibitor rapamycin, an agent that is currently under preclinical investigation for cancer. To date, the PPTP has completed in vitro testing of 39 investigational and approved agents for single drug activity and two investigational agents in combination with various “standard” chemotherapy drugs. Conclusions This robust in vitro cytotoxicity testing system for pediatric cancers will enable comparisons to response data for novel agents obtained from xenograft studies and from clinical trials. PMID:20922763
Nakata, Shiori; Watanabe, Tadashi; Nakagawa, Koji; Takeda, Hiroshi; Ito, Akihiro; Fujimuro, Masahiro
2016-03-25
Polyubiquitination plays key roles in proteasome-dependent and independent cellular events, whereas monoubiquitination is involved in gene expression, DNA repair, protein-protein interaction, and protein trafficking. We previously developed an FK2 antibody, which specifically recognizes poly-Ub moieties but not free Ub. To elucidate the role of Ub conjugation in response to cellular stress, we used FK2 to investigate whether chemical stress (rapamycin, ethanol, or hydroxyurea), ER stress (thapsigargin or tunicamycin), heat shock or DNA damage (H2O2 or methyl methanesulfonate) affect the formation of Ub conjugates including histone H2A (hH2A) ubiquitination. First, we found that all forms of stress tested increased poly-ubiquitinated proteins in HeLa cells. Furthermore, rapamycin and hydroxyurea treatment, and ER stress increased ubiquitination of hH2A, while methyl methanesulfonate (MMS) treatment induced deubiquitination of hH2A. The ethanol and H2O2 treatments, and heat shock transiently induced hH2A de-ubiquitination, although deubiquitinated hH2A were ubiquitinated again by subsequent cultivation. We also revealed that FK2 reacts with not only polyubiquitinated proteins but also mono-ubiquitinated hH2A. With the exception of MMS, all forms of stress tested increased the acetylation of K5-hH2A, K9-hH3 and K8-hH4 in addition to ubiquitination. K118 and K119 of hH2A were ubiquitinated in cells under normal conditions, and K119 was the major ubiquitination site. The MMS-treatment and heat shock induced the deubiquitination of both K118 and K119-histone H2A. Interestingly, MMS treatment did not affect cell HeLa cell viability expressing double-mutant hH2A (KK118,119AA-hH2A), while heat shock slightly but significantly decreased viability of double-mutant hH2A expressing cells, indicating that ubiquitination of both sites associates with recovery from heat shock but not MMS treatment. Thus, we characterized FK2 reactivity and demonstrated that various stresses alter the ubiquitination status, particularly ubiquitinated hH2A and with histone acetylation, and highlight the physiological importance of hH2A ubiquitination after exposure to stress stimuli. Copyright © 2016 Elsevier Inc. All rights reserved.
Khan, Tahira; Stewart, Mark; Blackman, Samuel; Rousseau, Raphaël; Donoghue, Martha; Cohen, Kenneth; Seibel, Nita; Fleury, Mark; Benettaib, Bouchra; Malik, Raleigh; Vassal, Gilles; Reaman, Gregory
2018-01-01
Although outcomes for children with cancer have significantly improved over the past 40 years, there has been little progress in the treatment of some pediatric cancers, particularly when advanced. Additionally, clinical trial options and availability are often insufficient. Improved genomic and immunologic understanding of pediatric cancers, combined with innovative clinical trial designs, may provide an enhanced opportunity to study childhood cancers. Master protocols, which incorporate the use of precision medicine approaches, coupled with the ability to quickly assess the safety and effectiveness of new therapies, have the potential to accelerate early-phase clinical testing of novel therapeutics and which may result in more rapid approval of new drugs for children with cancer. Designing and conducting master protocols for children requires addressing similar principles and requirements as traditional adult oncology trials, but there are also unique considerations for master protocols conducted in children with cancer. The purpose of this paper is to define the key challenges and opportunities associated with this approach in order to ensure that master protocols can be adapted to benefit children and adolescents and ensure that adequate data are captured to advance, in parallel, the clinical development of investigational agents for children with cancer.
Gentles, Stephen James; Lokker, Cynthia; McKibbon, K Ann
2010-06-18
Pediatric patients with health conditions requiring follow-up typically depend on a caregiver to mediate at least part of the necessary two-way communication with health care providers on their behalf. Health information technology (HIT) and its subset, information communication technology (ICT), are increasingly being applied to facilitate communication between health care provider and caregiver in these situations. Awareness of the extent and nature of published research involving HIT interventions used in this way is currently lacking. This scoping review was designed to map the health literature about HIT used to facilitate communication involving health care providers and caregivers (who are usually family members) of pediatric patients with health conditions requiring follow-up. Terms relating to care delivery, information technology, and pediatrics were combined to search MEDLINE, EMBASE, and CINAHL for the years 1996 to 2008. Eligible studies were selected after three rounds of duplicate screening in which all authors participated. Data regarding patient, caregiver, health care provider, HIT intervention, outcomes studied, and study design were extracted and maintained in a Microsoft Access database. Stage of research was categorized using the UK's Medical Research Council (MRC) framework for developing and evaluating complex interventions. Quantitative and qualitative descriptive summaries are presented. We included 104 eligible studies (112 articles) conducted in 17 different countries and representing 30 different health conditions. The most common conditions were asthma, type 1 diabetes, special needs, and psychiatric disorder. Most studies (88, 85%) included children 2 to 12 years of age, and 73 (71%) involved home care settings. Health care providers operated in hospital settings in 96 (92%) of the studies. Interventions featured 12 modes of communication (eg, Internet, intranets, telephone, video conferencing, email, short message service [SMS], and manual downloading of information) used to facilitate 15 categories of functions (eg, support, medication management, education, and monitoring). Numerous patient, caregiver, and health care relevant outcomes have been measured. Most outcomes concerned satisfaction, use, usability, feasibility, and resource use, although behavior changes and quality of life were also reported. Most studies (57 studies, 55%) were pilot phase, with a lesser proportion of development phase (24 studies, 23%) and evaluation phase (11 studies, 11%) studies. HIT interventions addressed several recurring themes in this review: establishing continuity of care, addressing time constraints, and bridging geographical barriers. HIT used in pediatric care involving caregivers has been implemented differently in a range of disease settings, with varying needs influencing the function, form and synchronicity of information transfer. Although some authors have followed a phased approach to development, evaluation and implementation, a greater emphasis on methodological standards such as the MRC guidance for complex interventions would produce more fruitful programs of development and more useful evaluations in the future. This review will be especially helpful to those deciding on areas where further development or research into HIT for this purpose may be warranted.
Geng, Feng; Tang, Li; Li, Yun; Yang, Lu; Choi, Kyoung-Soo; Kazim, A. Latif; Zhang, Yuesheng
2011-01-01
Allyl isothiocyanate (AITC) occurs in many commonly consumed cruciferous vegetables and exhibits significant anti-cancer activities. Available data suggest that it is particularly promising for bladder cancer prevention and/or treatment. Here, we show that AITC arrests human bladder cancer cells in mitosis and also induces apoptosis. Mitotic arrest by AITC was associated with increased ubiquitination and degradation of α- and β-tubulin. AITC directly binds to multiple cysteine residues of the tubulins. AITC induced mitochondrion-mediated apoptosis, as shown by cytochrome c release from mitochondria to cytoplasm, activation of caspase-9 and caspase-3, and formation of TUNEL-positive cells. Inhibition of caspase-9 blocked AITC-induced apoptosis. Moreover, we found that apoptosis induction by AITC depended entirely on mitotic arrest and was mediated via Bcl-2 phosphorylation at Ser-70. Pre-arresting cells in G1 phase by hydroxyurea abrogated both AITC-induced mitotic arrest and Bcl-2 phosphorylation. Overexpression of a Bcl-2 mutant prevented AITC from inducing apoptosis. We further showed that AITC-induced Bcl-2 phosphorylation was caused by c-Jun N-terminal kinase (JNK), and AITC activates JNK. Taken together, this study has revealed a novel anticancer mechanism of a phytochemical that is commonly present in human diet. PMID:21778226
De Souza, Colin P. C.; Ye, Xiang S.; Osmani, Stephen A.
1999-01-01
The G2 DNA damage and slowing of S-phase checkpoints over mitosis function through tyrosine phosphorylation of NIMXcdc2 in Aspergillus nidulans. We demonstrate that breaking these checkpoints leads to a defective premature mitosis followed by dramatic rereplication of genomic DNA. Two additional checkpoint functions, uvsB and uvsD, also cause the rereplication phenotype after their mutation allows premature mitosis in the presence of low concentrations of hydroxyurea. uvsB is shown to encode a rad3/ATR homologue, whereas uvsD displays homology to rad26, which has only previously been identified in Schizosaccharomyces pombe. uvsBrad3 and uvsDrad26 have G2 checkpoint functions over mitosis and another function essential for surviving DNA damage. The rereplication phenotype is accompanied by lack of NIMEcyclinB, but ectopic expression of active nondegradable NIMEcyclinB does not arrest DNA rereplication. DNA rereplication can also be induced in cells that enter mitosis prematurely because of lack of tyrosine phosphorylation of NIMXcdc2 and impaired anaphase-promoting complex function. The data demonstrate that lack of checkpoint control over mitosis can secondarily cause defects in the checkpoint system that prevents DNA rereplication in the absence of mitosis. This defines a new mechanism by which endoreplication of DNA can be triggered and maintained in eukaryotic cells. PMID:10564263
Hu, Zhubing; Cools, Toon; Kalhorzadeh, Pooneh; Heyman, Jefri; De Veylder, Lieven
2015-01-01
To maintain genome integrity, DNA replication is executed and regulated by a complex molecular network of numerous proteins, including helicases and cell cycle checkpoint regulators. Through a systematic screening for putative replication mutants, we identified an Arabidopsis thaliana homolog of human Regulator of Telomere Length 1 (RTEL1), which functions in DNA replication, DNA repair, and recombination. RTEL1 deficiency retards plant growth, a phenotype including a prolonged S-phase duration and decreased cell proliferation. Genetic analysis revealed that rtel1 mutant plants show activated cell cycle checkpoints, specific sensitivity to DNA cross-linking agents, and increased homologous recombination, but a lack of progressive shortening of telomeres, indicating that RTEL1 functions have only been partially conserved between mammals and plants. Surprisingly, RTEL1 deficiency induces tolerance to the deoxynucleotide-depleting drug hydroxyurea, which could be mimicked by DNA cross-linking agents. This resistance does not rely on the essential replication checkpoint regulator WEE1 but could be blocked by a mutation in the SOG1 transcription factor. Taken together, our data indicate that RTEL1 is required for DNA replication and that its deficiency activates a SOG1-dependent replication checkpoint. © 2015 American Society of Plant Biologists. All rights reserved.
Methods for Teratogenic Screening of Air Force Chemicals
1978-01-01
7 2 4 3 2.3 7 8 2 1 7 2.6 8 5 1 1 4 2.5 20 0 10 22 8 1 1 7 2.8 26 6 5 2 4 2.4 3 Gross Abnormalities Number of Fetuses with Abnormality Anophthalmia ...meningoencephalocoele), anophthalmia , cleft palate, cleft lip, misplaced ears, clubbed hind limbs, fused vertebrae, fused ribs, split centra and scoliosis.* In...experimentation with hydroxyurea in Fisher 344 rats, at 250 mg/kg on day nine of pregnancy, our results showed anophthalmia , brain abnormalities
Multiple myeloma on polycythemia vera following radioactive phosphorus therapy
DOE Office of Scientific and Technical Information (OSTI.GOV)
West, W.O.
1976-11-01
A 74-year-old white man with established polycythemia vera was treated with radioactive phosphorus after phlebotomies alone failed to control his disease. About 2/sup 3///sub 4/ years later he died of multiple myeloma. The mutagenic effect of radioactive phosphorus may have caused or possibly accelerated preexisting myeloma. Basic nonmalignant disease deserves careful consideration before radiation or radiomimetic agents are used. One might consider a probably less mutagenic drug such as hydroxyurea in patients with polycythemia vera when phlebotomy alone does not give good control of red cell mass and thrombocytosis.
Alteration of adenyl dinucleotide metabolism by environmental stress.
Baker, J C; Jacobson, M K
1986-01-01
Exposure of cultured mammalian cells to a variety of conditions that induce the synthesis of stress proteins, including hyperthermia, ethanol, cadmium, and arsenite resulted in an increased cellular content of adenyl dinucleotides including diadenosine tetraphosphate (Ap4A). Exposure to other agents that cause metabolic perturbations not known to induce the synthesis of stress proteins, such as cyclohexamide, cytosine arabinoside, hydroxyurea, and ultraviolet irradiation did not alter the content of these nucleotides. It is proposed that these unique nucleotides may mediate adaptive responses of mammalian cells to environmental stress. PMID:3458199
Malempati, Suman; Weigel, Brenda; Ingle, Ashish M.; Ahern, Charlotte H.; Carroll, Julie M.; Roberts, Charles T.; Reid, Joel M.; Schmechel, Stephen; Voss, Stephan D.; Cho, Steven Y.; Chen, Helen X.; Krailo, Mark D.; Adamson, Peter C.; Blaney, Susan M.
2012-01-01
Purpose A phase I/II study of cixutumumab (IMC-A12) in children with refractory solid tumors was conducted. This study was designed to assess the toxicities, pharmacokinetics, and pharmacodynamics of cixutumumab in children to determine a recommended phase II dose and to assess antitumor activity in Ewing sarcoma (ES). Patients and Methods Pediatric patients with relapsed or refractory solid tumors were treated with cixutumumab as a 1-hour intravenous infusion once per week. Two dose levels—6 and 9 mg/kg—were evaluated using a standard three-plus-three cohort design. Patients with refractory ES were treated in an expanded phase II cohort at each dose level. Results Forty-seven eligible patients with a median age of 15 years (range, 4 to 28 years) were enrolled. Twelve patients were treated in the dose-finding phase. Hematologic and nonhematologic toxicities were generally mild and infrequent. Dose-limiting toxicities included grade 4 thrombocytopenia at 6 mg/kg and grade 3 dehydration at 9 mg/kg. Mean trough concentration (± standard deviation) at 9 mg/kg was 106 ± 57 μg/mL, which exceeded the effective trough concentration of 60 μg/mL observed in xenograft models. Three patients with ES had confirmed partial responses: one of 10 at 6 mg/kg and two of 20 at 9 mg/kg. Serum insulin-like growth factor I (IGF-I) levels consistently increased after one dose of cixutumumab. Tumor IGF-I receptor expression by immunohistochemistry did not correlate with response in patients with ES. Conclusion Cixutumumab is well tolerated in children with refractory solid tumors. The recommended phase II dose is 9 mg/kg. Limited single-agent activity of cixutumumab was seen in ES. PMID:22184397
Nobili, V; Alisi, A; Newton, Kimberly P.; Schwimmer, Jeffrey B.
2016-01-01
Nonalcoholic fatty liver disease (NAFLD) is one of the main chronic non-communicable diseases in westernized societies; its worldwide prevalence has doubled during the last 20 years. NAFLD has serious health implications not only for adults, but also for children. However, pediatric NAFLD is not only an important global problem in itself, but it is likely to be associated with increases in comorbidities such as metabolic syndrome and cardiovascular diseases. There are several differences between NAFLD in children and adults and it is not clear whether the disease observed in children is the initial phase of a process that progresses with age. The increasing prevalence of pediatric NAFLD has serious implications for the future adult population requiring appropriate action. Studies of NAFLD progression, pathogenesis, and management should evaluate disease phenotypes in children and follow these over patient lifetimes. We review the similarities and differences of NAFLD between children and adults. PMID:27003600
Haylett, Wendy J
An antileukemic agent prescribed for pediatric oncology patients during the maintenance phase of therapy for acute lymphoblastic leukemia, 6-mercaptopurine (6-MP), is highly influenced by genetic variations in the thiopurine S-methyltransferase enzyme. As such, 6-MP must be dosed so that patients with 1 or 2 inactive thiopurine S-methyltransferase alleles will not incur an increased risk for myelosuppression or other toxicities. Informatics tools such as clinical decision support systems are useful for the application of this and similar pharmacogenetics information to the realm of nursing and clinical practice for safe and effective patient care. This article will discuss pharmacogenetics and the associated use of 6-MP; present implications for nursing practice; identify informatics tools such as clinical decision support systems, which can greatly enhance the care of patients whose treatment is based on critical genetic information; and examine the relationship of genetics, nursing practice, and informatics for 6-MP dosing in pediatric oncology.
Feeding and Swallowing Disorders in Pediatric Neuromuscular Diseases: An Overview
van den Engel-Hoek, Lenie; de Groot, Imelda J.M.; de Swart, Bert J.M.; Erasmus, Corrie E.
2015-01-01
Feeding and swallowing problems in infants and children have a great impact on health and wellbeing. The aim of this study was to provide an overview of recognized feeding and swallowing problems in different groups of children with neuromuscular diseases, based on relevant literature and expert opinion, and to propose recommendations for the assessment and treatment of these problems. Almost all pediatric neuromuscular diseases are accompanied by feeding and swallowing problems during the different phases of deglutition, problems that give rise to a wide variety of signs and symptoms, which emphasizes the importance of a comprehensive feeding and swallowing assessment by a speech and language therapist. PMID:27858755
Scott, Shannon D; Albrecht, Lauren; Given, Lisa M; Hartling, Lisa; Johnson, David W; Jabbour, Mona; Klassen, Terry P
2018-01-01
The majority of children requiring emergency care are treated in general emergency departments (EDs) with variable levels of pediatric care expertise. The goal of the Translating Emergency Knowledge for Kids (TREKK) initiative is to implement the latest research in pediatric emergency medicine in general EDs to reduce clinical variation. To determine national pediatric information needs, seeking behaviours, and preferences of health care professionals working in general EDs. An electronic cross-sectional survey was conducted with health care professionals in 32 Canadian general EDs. Data were collected in the EDs using the iPad and in-person data collectors. Total of 1,471 surveys were completed (57.1% response rate). Health care professionals sought information on children's health care by talking to colleagues (n=1,208, 82.1%), visiting specific medical/health websites (n=994, 67.7%), and professional development opportunities (n=941, 64.4%). Preferred child health resources included protocols and accepted treatments for common conditions (n=969, 68%), clinical pathways and practice guidelines (n=951, 66%), and evidence-based information on new diagnoses and treatments (n=866, 61%). Additional pediatric clinical information is needed about multisystem trauma (n=693, 49%), severe head injury (n=615, 43%), and meningitis (n=559, 39%). Health care professionals preferred to receive child health information through professional development opportunities (n=1,131, 80%) and printed summaries (n=885, 63%). By understanding health care professionals' information seeking behaviour, information needs, and information preferences, knowledge synthesis and knowledge translation initiatives can be targeted to improve pediatric emergency care. The findings from this study will inform the following two phases of the TREKK initiative to bridge the research-practice gap in Canadian general EDs.
Khaderi, Saira; Shepherd, Ross; Goss, John A; Leung, Daniel H
2014-08-28
The number of children affected by the hepatitis C virus (HCV) in the United States is estimated to be between 23000 to 46000. The projected medical cost for children with HCV in the United States is $199-366 million over the next decade. The implementation of routine screening of blood supply has virtually eliminated transmission via transfusion and vertical transmission is now the most common mode of infection in children. Infections acquired during infancy are more likely to spontaneously resolve and fibrosis of the liver tends to increase with age suggesting slow progressive histologic injury. Anti-viral treatment may be warranted in children with persistently elevated liver enzymes or with significant fibrosis on liver biopsy. Current standard of care includes weekly pegylated interferon and ribavirin twice daily. Predictors of high sustained viral response include genotype 2 and 3 and low viral load in children with genotype 1 (< 600000 IU/mL). Phase 1 and 2 trials with triple therapy (interferon, ribavirin, and a protease inhibitor) are ongoing. Triple therapy is associated with a significantly higher rate of sustained virologic response (> 90%). Only 34 pediatric patients were transplanted with hepatitis C between January 2008 and April 2013. The majority of pediatric patients were born prior to universal screening of blood products and, as of June 2013, there are only two pediatric patients awaiting liver transplantation for end-stage liver disease secondary to hepatitis C. Pediatric survival rates post-transplant are excellent but graft survivals are noticeably reduced compared to adults (73.73% for pediatric patients at one year compared to 87.69% in adult patients). New safe and effective antiviral therapies for recurrent HCV should help increase graft survival.
Benito, Sandra; Sánchez, Alicia; Unceta, Nora; Andrade, Fernando; Aldámiz-Echevarria, Luis; Goicolea, M Aránzazu; Barrio, Ramón J
2016-01-01
Chronic kidney disease (CKD) is a major epidemiologic problem which causes several disturbances in adults and in pediatrics. Despite being a worldwide public health problem, information available for CKD in the pediatric population is scarce. For that reason, an ion-pair reversed-phase liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) method has been developed and validated in order to analyze 16 amino acids, amino acid derivatives, and analogous compounds related to the arginine-creatine metabolic pathway that are suspicious of being increased or decreased in plasma from patients with CKD. The analytical method involved the addition of dithiothreitol, a reducing agent which reduces disulfide and thus giving total aminothiol concentration, as well as a simple precipitation of plasma proteins. Moreover, despite amino acids being usually derivatized to improve their retention time and to enhance their signal, for this method, an ion-pairing reagent was used, thus avoiding the need for derivatization. Subsequently, analysis of plasma from pediatric patients suffering from CKD and control pediatrics was carried out. As a result, glycine, citrulline, creatinine, asymmetric dimethylarginine (ADMA), and symmetric dimethylarginine (SDMA) were significantly increased in patients with CKD, regardless of their creatinine level, whereas in addition to these compounds dimethylglycine was also increased when CKD patients had plasma creatinine concentrations above 12 μg mL(-1), thus all are suggested as potential biomarkers for renal impairment.
Integration Of An MR Image Network Into A Clinical PACS
NASA Astrophysics Data System (ADS)
Ratib, Osman M.; Mankovich, Nicholas J.; Taira, Ricky K.; Cho, Paul S.; Huang, H. K.
1988-06-01
A direct link between a clinical pediatric PACS module and a FONAR MRI image network was implemented. The original MR network combines together the MR scanner, a remote viewing station and a central archiving station. The pediatric PACS directly connects to the archiving unit through an Ethernet TCP-IP network adhering to FONAR's protocol. The PACS communication software developed supports the transfer of patient studies and the patient information directly from the MR archive database to the pediatric PACS. In the first phase of our project we developed a package to transfer data between a VAX-111750 and the IBM PC I AT-based MR archive database through the Ethernet network. This system served as a model for PACS-to-modality network communication. Once testing was complete on this research network, the software and network hardware was moved to the clinical pediatric VAX for full PACS integration. In parallel to the direct transmission of digital images to the Pediatric PACS, a broadband communication system in video format was developed for real-time broadcasting of images originating from the MR console to 8 remote viewing stations distributed in the radiology department. These analog viewing stations allow the radiologists to directly monitor patient positioning and to select the scan levels during a patient examination from remote locations in the radiology department. This paper reports (1) the technical details of this implementation, (2) the merits of this network development scheme, and (3) the performance statistics of the network-to-PACS interface.
Sun, Weili; Liu, Huaying; Kim, Young; Karras, Nicole; Pawlowska, Anna; Toomey, Debbie; Kyono, Wade; Gaynon, Paul; Rosenthal, Joseph; Stein, Anthony
2018-05-02
Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a highly aggressive hematological malignancy with extremely poor outcome. The median overall survival for adult patients is 9-13 months. Pediatric patients are exceedingly rare with an unclear clinical course. Currently, no standardized therapy has been established, although an acute lymphoblastic leukemia type of treatment appears to be more effective in those patients who are able to tolerate aggressive chemotherapy. SL-401 is a targeted therapy directed to CD123, a protein ubiquitously expressed at high level on the surface of BPDCN blasts. In adult phase 2 trials, it has demonstrated efficacy with 90% overall response rate. No pediatric patients with BPDCN using SL-401 have been reported. Here, we report the first pediatric experience of three children with BPDCN treated with SL-401 at our institution. All patients tolerated SL-401 without significant toxicities. One patient with multiply relapsed and refractory disease had no response. The other two cases had significant and rapid clinical improvement after the two courses of treatment. However, the response was transient, and growth of soft tissue mass was observed in-between cycles in both patients with large tumor burden. This is the first report of SL-401 in pediatric patients with BPDCN. Sl-401 was well tolerated and can produce a promising response. Further testing this agent in children is warranted.
Landscape of early clinical trials for childhood and adolescence cancer in Spain.
Bautista, F; Gallego, S; Cañete, A; Mora, J; Diaz de Heredia, C; Cruz, O; Fernández, J M; Rives, S; Madero, L; Castel, V; Cela, M E; Ramírez, G; Sábado, C; Acha, T; Astigarraga, I; Sastre, A; Muñoz, A; Guibelalde, M; Moreno, L
2016-07-01
Despite numerous advances, survival remains dismal for children and adolescents with poor prognosis cancers or those who relapse or are refractory to first line treatment. There is, therefore, a major unmet need for new drugs. Recent advances in the knowledge of molecular tumor biology open the door to more adapted therapies according to individual alterations. Promising results in the adult anticancer drug development have not yet been translated into clinical practice. We report the activity in early pediatric oncology trials in Spain. All members of the Spanish Society of Pediatric Hematology Oncology (SEHOP) were contacted to obtain information about early trials open in each center. 22 phase I and II trials were open as of May 2015: 15 for solid tumors (68 %) and 7 for hematological malignancies (32 %). Fourteen (64 %) were industry sponsored. Since 2010, four centers have joined the Innovative Therapies For Children With Cancer, an international consortium whose aim is developing novel therapies for pediatric cancers. A substantial number of studies have opened in these 5 years, improving the portfolio of trials for children. Results of recently closed trials show the contribution of Spanish investigators, the introduction of molecularly targeted agents and their benefits. Clinical trials are the way to evaluate new drugs, avoiding the use of off-label drugs that carry significant risks. The Spanish pediatric oncology community through the SEHOP is committed to develop and participate in collaborative academic trials, to favor the advancement and optimization of existing therapies in pediatric cancer.
Burckhardt, Bjoern B; Ramusovic, Sergej; Tins, Jutta; Laeer, Stephanie
2013-04-01
The orally active direct renin inhibitor aliskiren is approved for the treatment of essential hypertension in adults. Analytical methods utilized in clinical studies on efficacy and safety have not been fully described in the literature but need a large sample volume ranging from 200 to 700 μL, rendering them unsuitable particularly for pediatric applications. In the assay presented only 100 μL of serum is needed for mixed-mode solid-phase extraction. The chromatographic separation was performed on Xselect(TM) C18 CSH columns with mobile phase consisting of methanol-water-formic acid (75:25:0.005, v/v/v) and a flow rate of 0.4 mL/min. Running in positive electrospray ionization and multiple reaction monitoring the mass spectrometer was set to analyze precursor ion 552.2 m/z [M + H](+) to product ion 436.2 m/z during a total run time of 5 min. The method covers a linear calibration range of 0.146-1200 ng/mL. Intra-run and inter-run precisions were 0.4-7.2 and 0.6-12.9%. Mean recovery was at least 89%. Selectivity, accuracy and stability results comply with current European Medicines Agency and Food and Drug Administration guidelines. This successfully validated LC-MS/MS method with a wide linear calibration range requiring small serum amounts is suitable for pharmacokinetic investigations of aliskiren in pediatrics, adults and the elderly. Copyright © 2012 John Wiley & Sons, Ltd.
Li, Meng-Ju; Chang, Hsiu-Hao; Yang, Yung-Li; Lu, Meng-Yao; Shao, Pei-Lan; Fu, Chun-Min; Chou, An-Kuo; Liu, Yen-Lin; Lin, Kai-Hsin; Huang, Li-Min; Lin, Dong-Tsamn; Jou, Shiann-Tarng
2017-10-01
Infection is a major complication in pediatric patients with acute lymphoblastic leukemia during chemotherapy. In this study, the infection characteristics were determined and risk factors analyzed based on the Taiwan Pediatric Oncology Group (TPOG) acute lymphoblastic leukemia (ALL) protocol. We retrospectively reviewed fever events during chemotherapy in 252 patients treated during two consecutive clinical trials at a single institution between 1997 and 2012. Patients were classified as standard, high, and very high risk by treatment regimen according to the TPOG definitions. We analyzed the characteristics and risk factors for infection. Fever occurred in 219 patients (86.9%) with a mean of 2.74 episodes per person. The fever events comprised 64% febrile neutropenia, 39% clinically documented infections, and 44% microbiologically documented infections. The microbiologically documented infections were mostly noted during the induction phase and increased in very high risk patients (89 vs. 24% and 46% in standard-risk and high-risk patients, respectively). Younger age and higher risk (high-risk and very high risk groups) were risk factors for fever and microbiologic and bloodstream infections. Female gender and obesity were additive risk factors for urinary tract infection (odds ratios = 3.52 and 3.24, P < 0.001 and P = 0.004, respectively). Infections developed primarily during the induction phase, for which younger age and higher risk by treatment regimen were risk factors. Female gender and obesity were additive risk factors for urinary tract infection. © 2017 Wiley Periodicals, Inc.
Chaplais, Elodie; Naughton, Geraldine; Thivel, David; Courteix, Daniel; Greene, David
2015-10-01
Traditional approaches for treating or managing children and adolescents with overweight or obesity have limited effectiveness. Current advances in smartphone technology may improve the attractiveness and accessibility of weight management support for children and adolescents with overweight or obesity. This systematic review aimed to provide a comparative evaluation of the effectiveness of using smartphones in the multidisciplinary treatment of child and adolescent overweight or obesity, with a specific interest in behavior change. The databases of Medline complete, OVID, CINAHL, EMBASE, and PubMed were searched for randomized controlled trial (RCT) studies addressing behavioral change using smartphone technology, plus nutrition and/or physical activity, to treat or manage child and adolescent obesity. Only two RCTs have described the effectiveness of smartphone devices in pediatric overweight or obesity treatment. Within the limitation of the two studies, electronic contact (e-contact) appeared unsuccessful in achieving weight loss. However, smartphone usage was linked to improved engagement and reduced dropout rates during important sustainability phases of these long-term interventions. Smartphone technologies allow users to accomplish tasks anywhere and anytime and, as such, provide researchers with additional and generationally appropriate capacities to deliver health promotion. E-contact should be used for its significant capacity to prolong engagement and decrease withdrawal during sustainability phases that follow intensive intervention for weight management in young populations. Despite increasing popularity in published protocols of weight management trials, the effectiveness of the impact of smartphone technology in pediatric programs remains equivocal.
Risk factors for near-miss events and safety incidents in pediatric radiation therapy.
Baig, Nimrah; Wang, Jiangxia; Elnahal, Shereef; McNutt, Todd; Wright, Jean; DeWeese, Theodore; Terezakis, Stephanie
2018-05-01
Factors contributing to safety- or quality-related incidents (e.g. variances) in children are unknown. We identified clinical and RT treatment variables associated with risk for variances in a pediatric cohort. Using our institution's incident learning system, 81 patients age ≤21 years old who experienced variances were compared to 191 pediatric patients without variances. Clinical and RT treatment variables were evaluated as potential predictors for variances using univariate and multivariate analyses. Variances were primarily documentation errors (n = 46, 57%) and were most commonly detected during treatment planning (n = 14, 21%). Treatment planning errors constituted the majority (n = 16 out of 29, 55%) of near-misses and safety incidents (NMSI), which excludes workflow incidents. Therapists reported the majority of variances (n = 50, 62%). Physician cross-coverage (OR = 2.1, 95% CI = 1.04-4.38) and 3D conformal RT (OR = 2.3, 95% CI = 1.11-4.69) increased variance risk. Conversely, age >14 years (OR = 0.5, 95% CI = 0.28-0.88) and diagnosis of abdominal tumor (OR = 0.2, 95% CI = 0.04-0.59) decreased variance risk. Variances in children occurred in early treatment phases, but were detected at later workflow stages. Quality measures should be implemented during early treatment phases with a focus on younger children and those cared for by cross-covering physicians. Copyright © 2018 Elsevier B.V. All rights reserved.
Karagiozoglou-Lampoudi, Thomais; Daskalou, Efstratia; Lampoudis, Dimitrios; Apostolou, Aggeliki; Agakidis, Charalampos
2015-05-01
The study aimed to test the hypothesis that computer-based calculation of malnutrition risk may enhance the ability to identify pediatric patients at malnutrition-related risk for an unfavorable outcome. The Pediatric Digital Scaled MAlnutrition Risk screening Tool (PeDiSMART), incorporating the World Health Organization (WHO) growth reference data and malnutrition-related parameters, was used. This was a prospective cohort study of 500 pediatric patients aged 1 month to 17 years. Upon admission, the PeDiSMART score was calculated and anthropometry was performed. Pediatric Yorkhill Malnutrition Score (PYMS), Screening Tool Risk on Nutritional Status and Growth (STRONGkids), and Screening Tool for the Assessment of Malnutrition in Pediatrics (STAMP) malnutrition screening tools were also applied. PeDiSMART's association with the clinical outcome measures (weight loss/nutrition support and hospitalization duration) was assessed and compared with the other screening tools. The PeDiSMART score was inversely correlated with anthropometry and bioelectrical impedance phase angle (BIA PhA). The score's grading scale was based on BIA Pha quartiles. Weight loss/nutrition support during hospitalization was significantly independently associated with the malnutrition risk group allocation on admission, after controlling for anthropometric parameters and age. Receiver operating characteristic curve analysis showed a sensitivity of 87% and a specificity of 75% and a significant area under the curve, which differed significantly from that of STRONGkids and STAMP. In the subgroups of patients with PeDiSMART-based risk allocation different from that based on the other tools, PeDiSMART allocation was more closely related to outcome measures. PeDiSMART, applicable to the full age range of patients hospitalized in pediatric departments, graded according to BIA PhA, and embeddable in medical electronic records, enhances efficacy and reproducibility in identifying pediatric patients at malnutrition-related risk for an unfavorable outcome. Patient allocation according to the PeDiSMART score on admission is associated with clinical outcome measures. © 2014 American Society for Parenteral and Enteral Nutrition.
Potential of Three Ethnomedicinal Plants as Antisickling Agents.
Nurain, Ismaila O; Bewaji, Clement O; Johnson, Jarrett S; Davenport, Robertson D; Zhang, Yang
2017-01-03
Sickle cell disease (SCD) is a genetic blood disorder that affects the shape and transportation of red blood cells (RBCs) in blood vessels, leading to various clinical complications. Many drugs that are available for treating the disease are insufficiently effective, toxic, or too expensive. Therefore, there is a pressing need for safe, effective, and inexpensive therapeutic agents from indigenous plants used in ethnomedicines. The potential of aqueous extracts of Cajanus cajan leaf and seed, Zanthoxylum zanthoxyloides leaf, and Carica papaya leaf in sickle cell disease management was investigated in vitro using freshly prepared 2% sodium metabisulfite for sickling induction. The results indicated that the percentage of sickled cells, which was initially 91.6% in the control, was reduced to 29.3%, 41.7%, 32.8%, 38.2%, 47.6%, in the presence of hydroxyurea, C. cajan seed, C. cajan leaf, Z. zanthoxyloides leaf, and C. papaya leaf extracts, respectively, where the rate of polymerization inhibition was 6.5, 5.9, 8.0, 6.6, and 6.0 (×10 -2 ) accordingly. It was also found that the RBC resistance to hemolysis was increased in the presence of the tested agents as indicated by the reduction of the percentage of hemolyzed cells from 100% to 0%. The phytochemical screening results indicated the presence of important phytochemicals including tannins, saponins, alkaloids, flavonoids, and glycosides in all the plant extracts. Finally, gas chromatography-mass spectrometry analysis showed the presence of important secondary metabolites in the plants. These results suggest that the plant extracts have some potential to be used as alternative antisickling therapy to hydroxyurea in SCD management.
Hydroxycarbamide treatment and brain MRI/MRA findings in children with sickle cell anaemia.
Nottage, Kerri A; Ware, Russell E; Aygun, Banu; Smeltzer, Matthew; Kang, Guolian; Moen, Joseph; Wang, Winfred C; Hankins, Jane S; Helton, Kathleen J
2016-10-01
Silent cerebral infarction (SCI) is the most common neurological abnormality among children with sickle cell anaemia (SCA). The effect of hydroxycarbamide (also termed hydroxyurea) on the development and progression of SCI is unclear. We evaluated brain magnetic resonance imaging/angiography (MRI/MRA) in children with SCA receiving long-term hydroxycarbamide therapy. Fifty participants (median 9·4 years, range 1·1-17·3) enrolled in the Hydroxyurea Study of Long-Term Effects (HUSTLE; NCT00305175) underwent brain MRI/MRA and laboratory evaluations before hydroxycarbamide initiation and after 3 and 6 years of treatment to maximum tolerated dose. SCI and vascular stenosis were evaluated. At baseline, 3 and 6 years, SCI were present in 19/50 (38%), 20/49 (41%), and 7/17 (41%), respectively. At 3 years, one child developed a SCI lesion, and another progressed (single lesion to multiple). Lower haemoglobin (Hb) (80 g/l vs. 86 g/l, P = 0·049), fetal Hb (5·0% vs. 10·4%, P < 0·001) and oxygen saturation (97% vs. 98%, P = 0·027) before hydroxycarbamide initiation were associated with SCI. No patients had vascular stenosis identified on MRA, transient ischaemic attack or stroke. Our data indicate that children receiving hydroxycarbamide over a 3- to 6-year period have a low rate of new or worsening cerebrovascular disease. Further studies are needed to confirm that hydroxycarbamide can prevent the onset and progression of SCI. © 2016 John Wiley & Sons Ltd.
Helton, Kathleen J.; Adams, Robert J.; Kesler, Karen L.; Lockhart, Alex; Aygun, Banu; Driscoll, Catherine; Heeney, Matthew M.; Jackson, Sherron M.; Krishnamurti, Lakshmanan; Miller, Scott T.; Sarnaik, Sharada A.; Schultz, William H.
2014-01-01
The Stroke With Transfusions Changing to Hydroxyurea (SWiTCH) trial compared standard (transfusions/chelation) to alternative (hydroxyurea/phlebotomy) treatment to prevent recurrent stroke and manage iron overload in children chronically transfused over 7 years before enrollment. Standardized brain magnetic resonance imaging/magnetic resonance angiography (MRA) and transcranial Doppler (TCD) exams were performed at entry and exit, with a central blinded review. A novel MRA vasculopathy grading scale demonstrated frequent severe baseline left/right vessel stenosis (53%/41% ≥Grade 4); 31% had no vessel stenosis on either side. Baseline parenchymal injury was prevalent (85%/79% subcortical, 53%/37% cortical, 50%/35% subcortical and cortical). Most children had low or uninterpretable baseline middle cerebral artery TCD velocities, which were associated with worse stenoses (incidence risk ratio [IRR] = 5.1, P ≤ .0001 and IRR = 4.1, P < .0001) than normal velocities; only 2% to 12% had any conditional/abnormal velocity. Patients with adjudicated stroke (7) and transient ischemic attacks (19 in 11 standard/8 alternative arm subjects) had substantial parenchymal injury/vessel stenosis. At exit, 1 child (alternative arm) had a new silent infarct, and another had worse stenosis. SWiTCH neuroimaging data document severe parenchymal and vascular abnormalities in children with SCA and stroke and support concerns about chronic transfusions lacking effectiveness for preventing progressive cerebrovascular injury. The novel SWiTCH vasculopathy grading scale warrants validation testing and consideration for use in future clinical trials. This trial was registered at www.clinicaltrials.gov as #NCT00122980. PMID:24914136
Beveridge, Ryan D; Staples, Christopher J; Patil, Abhijit A; Myers, Katie N; Maslen, Sarah; Skehel, J Mark; Boulton, Simon J; Collis, Spencer J
2014-01-01
We previously identified and characterized TELO2 as a human protein that facilitates efficient DNA damage response (DDR) signaling. A subsequent yeast 2-hybrid screen identified LARG; Leukemia-Associated Rho Guanine Nucleotide Exchange Factor (also known as Arhgef12), as a potential novel TELO2 interactor. LARG was previously shown to interact with Pericentrin (PCNT), which, like TELO2, is required for efficient replication stress signaling. Here we confirm interactions between LARG, TELO2 and PCNT and show that a sub-set of LARG co-localizes with PCNT at the centrosome. LARG-deficient cells exhibit replication stress signaling defects as evidenced by; supernumerary centrosomes, reduced replication stress-induced γH2AX and RPA nuclear foci formation, and reduced activation of the replication stress signaling effector kinase Chk1 in response to hydroxyurea. As such, LARG-deficient cells are sensitive to replication stress-inducing agents such as hydroxyurea and mitomycin C. Conversely we also show that depletion of TELO2 and the replication stress signaling kinase ATR leads to RhoA signaling defects. These data therefore reveal a level of crosstalk between the RhoA and DDR signaling pathways. Given that mutations in both ATR and PCNT can give rise to the related primordial dwarfism disorders of Seckel Syndrome and Microcephalic osteodysplastic primordial dwarfism type II (MOPDII) respectively, which both exhibit defects in ATR-dependent checkpoint signaling, these data also raise the possibility that mutations in LARG or disruption to RhoA signaling may be contributory factors to the etiology of a sub-set of primordial dwarfism disorders. PMID:25485589
Hydroxyurea and Growth in Young Children With Sickle Cell Disease
Houston, Patricia E.; Wang, Winfred C.; Iyer, Rathi V.; Goldsmith, Jonathan; Casella, James F.; Reed, Caroline K.; Rogers, Zora R.; Waclawiw, Myron A.; Thompson, Bruce
2014-01-01
BACKGROUND: Growth impairment is a known complication of sickle cell disease. Effects of hydroxyurea (HU) on growth in very young children are not known. METHODS: Height, weight, BMI, and head circumference (HC) were compared with World Health Organization (WHO) standards in BABY HUG, a multicenter, randomized, double-blinded, placebo-controlled 2-year clinical trial of HU in 193 children 9 to 18 months of age. Anthropometric data were closely monitored and converted to z scores by using WHO standardized algorithms for descriptive analyses. The treatment and placebo groups were compared longitudinally by using a mixed model analysis. RESULTS: At entry, the z scores of BABY HUG children were higher than WHO norms. After 2 years of HU or placebo treatment, there were no significant differences between the groups, except for the mean HC z scores at study exit (HU: +0.8 versus placebo: +1.0, P = .05). Baseline z scores were the best predictors of z scores at study exit. The absolute neutrophil count, absolute reticulocyte count, and total white blood cell count had significant negative correlations with growth measures. CONCLUSIONS: Both groups had normal or near normal anthropometric measures during the study. The HC z scores at study entry and exit were slightly greater than WHO norms. Higher baseline white blood cell count, absolute reticulocyte count, and absolute neutrophil count were associated with poorer growth. The significance of the slightly lower HC in the treatment group at study exit is not clear. Trends toward normalization of weight and height and effects on HC will be monitored in ongoing BABY HUG follow-up studies. PMID:25157002
[Symptomatic extramedullary haematopoiesis in β-thalassemia: A retrospective single centre study].
Maazoun, F; Gellen Dautremer, J; Boutekadjirt, A; Pissard, S; Habibi, A; Bachir, D; Rahmouni, A; Bartolucci, P; Debbache, K; Lagrange, J-L; Michel, M; Galacteros, F
2016-01-01
Symptomatic extramedullary hematopoiesis (EH) is a rare but potentially severe phenomenon which occurs in β-thalassemia. There are no treatment guidelines. Retrospective single centre study including the cases of symptomatic EH encountered between 1997 and 2014 in a unit specialised in red blood cell genetic disorders. Description of clinical, biological and radiological characteristics of the patients, treatments received, and outcomes. Among 182 β-thalassemia patients followed during the study period, 7 cases of symptomatic EH were diagnosed. They were 5 men and 2 women, and their mean age was 37 years. Four patients were splenectomised, two patients were regularly transfused, and four patients had already received erythropoietin. EH was localised in intravertebral areas and responsible for dorsal spinal cord compression in 5 patients, in paravertebral dorsal area in 1 patient, and in presacral area in 1 patient. The mean hemoglobin level at diagnosis was 7.9 g/dL. Treatment administered included: red cell transfusion in 6 cases, associated with hydroxyurea in 5 cases and/or radiotherapy in 3 patients. One patient was treated with surgery and HU. After a median follow-up of 41 months, clinical recovery was complete in 2 patients and partial in 5 patients. EH must be suspected in β-thalassemia in patients presenting clinical signs of organ compression, and a typical radiological aspect. The functional prognosis depends on the rapidity of treatment, which includes red blood cell transfusion, hydroxyurea, radiotherapy, and rarely surgery. Long-term outcome is uncertain. Copyright © 2015. Published by Elsevier SAS.
Wu, J R; Yeh, Y C
1975-05-01
Suppressors of gene 59-defective mutants were isolated by screening spontaneous, temperature-sensitive (ts) revertants of the amber mutant, amC5, in gene 59. Six ts revertants were isolated. No gene 59-defective ts recombinant was obtained by crossing each ts revertant with the wild type, T4D. However, suppressors of gene 59-defective mutants were obtained from two of these ts revertants. These suppressor mutants are referred to as dar (DNA arrested restoration). dar mutants specifically restored the abnormalities, both in DNA synthesis and burst size, caused by gene 59-defective mutants to normal levels. It is unlikely that dar mutants are nonsense suppressors since theý failed to suppress amber mutations in 11 other genes investigated. The genetic expression of dar is controlled by gene 55; therefore, dar is a late gene. The genetic location of dar has been mapped between genes 24 and 25, a region contiguous to late genes. dar appears to be another nonessential gene of T4 since burst sizes of dar were almost identical to those of the wild type. Mutations in dar did not affect genetic recombination and repair of UV-damaged DNA, but caused a sensitivity to hydroxyurea in progeny formation. The effect of the dar mutation on host DNA degradation cannot account for its hydroxyurea sensitivity. dar mutant alleles were recessive to the wild-type allele as judged by restoration of arrested DNA synthesis. The possible mechanisms for the suppression of defects in gene 59 are discussed.
Martí, Joaquín; Molina, Vanesa; Santa-Cruz, M C; Hervás, José P
2017-02-01
Postnatal development of the cerebellar cortex was studied in rats administered with a single dose (2 mg/g) of the cytotoxic agent hydroxyurea (HU) on postnatal day (P) 9 and collected at appropriate times ranging from 6 h to 45 days. Quantification of several parameters such as the density of pyknotic, mitotic, BrdU-positive, and vimentin-stained cells revealed that HU compromises the survival of the external granular layer (EGL) cells. Moreover, vimentin immunocytochemistry revealed overexpression and thicker immunoreactive glial processes in HU-treated rats. On the other hand, we also show that HU leads to the activation of apoptotic cellular events, resulting in a substantial number of dying EGL cells, as revealed by TUNEL staining and at the electron microscope level. Additionally, we quantified several features of the cerebellar cortex of rats exposed to HU in early postnatal life and collected in adulthood. Data analysis indicated that the analyzed parameters were less pronounced in rats administered with this agent. Moreover, we observed several alterations in the cerebellar cortex cytoarchitecture of rats injected with HU. Anomalies included ectopic placement of Purkinje cells and abnormities in the dendritic arbor of these macroneurons. Ectopic granule cells were also found in the molecular layer. These findings provide a clue for investigating the mechanisms of HU-induced toxicity during the development of the central nervous system. Our results also suggest that it is essential to avoid underestimating the adverse effects of this hydroxylated analog of urea when administered during early postnatal life.
Álvarez-González, Isela; Vázquez-Sánchez, Jorge; Chamorro-Cevallos, Germán; Madrigal-Bujaidar, Eduardo
2013-11-01
The purpose of the present report was to determine the inhibitory effect of Spirulina maxima (Sm) and its protein extract (PE), mainly consisting of C-phycocyanin, on the increase in micronuclei and bone marrow cytotoxicity induced by hydroxyurea (HU) in pregnant mice and their fetuses. The two tested antimutagenic agents were administered daily from day 10 to day 18 of pregnancy, and HU (300 mg/kg) was administered once on day 16 of the assay. The experimental design also included mice that were administered only Sm or PE (1000 and 400 mg/kg, respectively), two control groups that were administered with vehicles (water and 0.5% Tween 80), and one additional group that was treated solely with HU. Blood samples from the pregnant mice and their fetuses were examined at day 19 of pregnancy. Significant increases in the number of micronucleated polychromatic erythrocytes and in the total number of micronucleated erythrocytes were observed in all HU-treated animals. In contrast, similarly low numbers of micronuclei were observed in the two control groups and in the groups treated with Sm and PE alone. The administration of Sm (100, 500, and 1000 mg/kg) and PE (100, 200, and 400 mg/kg) to HU-treated animals conferred moderate genotoxic protection (∼30%) and some protection against the cytotoxicity induced by HU in mice. The obtained results provide new information regarding the capacity of the tested agents to confer protection to adult mice and transplacentally, as well as on a specific subclass of micronuclei.
Burckhardt, Bjoern B.; Laeer, Stephanie
2015-01-01
In USA and Europe, medicines agencies force the development of child-appropriate medications and intend to increase the availability of information on the pediatric use. This asks for bioanalytical methods which are able to deal with small sample volumes as the trial-related blood lost is very restricted in children. Broadly used HPLC-MS/MS, being able to cope with small volumes, is susceptible to matrix effects. The latter restrains the precise drug quantification through, for example, causing signal suppression. Sophisticated sample preparation and purification utilizing solid-phase extraction was applied to reduce and control matrix effects. A scale-up from vacuum manifold to positive pressure manifold was conducted to meet the demands of high-throughput within a clinical setting. Faced challenges, advances, and experiences in solid-phase extraction are exemplarily presented on the basis of the bioanalytical method development and validation of low-volume samples (50 μL serum). Enalapril, enalaprilat, and benazepril served as sample drugs. The applied sample preparation and extraction successfully reduced the absolute and relative matrix effect to comply with international guidelines. Recoveries ranged from 77 to 104% for enalapril and from 93 to 118% for enalaprilat. The bioanalytical method comprising sample extraction by solid-phase extraction was fully validated according to FDA and EMA bioanalytical guidelines and was used in a Phase I study in 24 volunteers. PMID:25873972
Can pegylated interferon improve the outcome of polycythemia vera patients?
Crisà, Elena; Cerrano, Marco; Beggiato, Eloise; Benevolo, Giulia; Lanzarone, Giuseppe; Manzini, Paola Maria; Borchiellini, Alessandra; Riera, Ludovica; Boccadoro, Mario; Ferrero, Dario
2017-01-13
Pegylated interferon (peg-IFN) was proven by phase II trials to be effective in polycythemia vera (PV); however, it is not clear whether it could improve patient outcome compared to hydroxyurea (HU). Here, we present an observational study on 65 PV patients aged 65 years or younger, who received either peg-IFN (30) or HU (35) according to the physician choice. Median follow-up was 75 months. The two cohorts were comparable for patient and disease characteristics. Eighty-seven percent of the patients treated with peg-INF responded, with a CR rate of 70% as compared to 100 and 49% with HU, respectively. Discontinuation rate was similar in the two groups (20% in peg-IFN vs 17% in HU). JAK2 allele burden was monitored in peg-INF arm only, and a reduction was observed in 88% of the patients. No thrombotic events were observed during peg-IFN treatment compared to three on HU. Disease progression to myelofibrosis or acute myeloid leukemia occurred to a patient only in peg-INF, compared to three in HU. Overall, three second malignancies were observed during the study, two in patients who received HU only, and one in a patient largely treated HU who received also peg-IFN for 3 months. Overall survival was significantly better for peg-IFN patients compared to HU, p = 0.027. Our study, albeit limited by small patient and event number and lack of randomization, confirms the efficacy of peg-INF in PV and shows a significant survival advantage for peg-INF-treated patients. Waiting for confirming data from the ongoing phase III trials, our study can support peg-INF as a first-line treatment option for PV, at least for younger patients.
Analysis of replication factories in human cells by super-resolution light microscopy
2009-01-01
Background DNA replication in human cells is performed in discrete sub-nuclear locations known as replication foci or factories. These factories form in the nucleus during S phase and are sites of DNA synthesis and high local concentrations of enzymes required for chromatin replication. Why these structures are required, and how they are organised internally has yet to be identified. It has been difficult to analyse the structure of these factories as they are small in size and thus below the resolution limit of the standard confocal microscope. We have used stimulated emission depletion (STED) microscopy, which improves on the resolving power of the confocal microscope, to probe the structure of these factories at sub-diffraction limit resolution. Results Using immunofluorescent imaging of PCNA (proliferating cell nuclear antigen) and RPA (replication protein A) we show that factories are smaller in size (approximately 150 nm diameter), and greater in number (up to 1400 in an early S- phase nucleus), than is determined by confocal imaging. The replication inhibitor hydroxyurea caused an approximately 40% reduction in number and a 30% increase in diameter of replication factories, changes that were not clearly identified by standard confocal imaging. Conclusions These measurements for replication factory size now approach the dimensions suggested by electron microscopy. This agreement between these two methods, that use very different sample preparation and imaging conditions, suggests that we have arrived at a true measurement for the size of these structures. The number of individual factories present in a single nucleus that we measure using this system is greater than has been previously reported. This analysis therefore suggests that each replication factory contains fewer active replication forks than previously envisaged. PMID:20015367
Jacobson, M D; Muñoz, C X; Knox, K S; Williams, B E; Lu, L L; Cross, F R; Vallen, E A
2001-01-01
SIC1 encodes a nonessential B-type cyclin/CDK inhibitor that functions at the G1/S transition and the exit from mitosis. To understand more completely the regulation of these transitions, mutations causing synthetic lethality with sic1 Delta were isolated. In this screen, we identified a novel gene, SID2, which encodes an essential protein that appears to be required for DNA replication or repair. sid2-1 sic1 Delta strains and sid2-21 temperature-sensitive strains arrest preanaphase as large-budded cells with a single nucleus, a short spindle, and an approximately 2C DNA content. RAD9, which is necessary for the DNA damage checkpoint, is required for the preanaphase arrest of sid2-1 sic1 Delta cells. Analysis of chromosomes in mutant sid2-21 cells by field inversion gel electrophoresis suggests the presence of replication forks and bubbles at the arrest. Deleting the two S phase cyclins, CLB5 and CLB6, substantially suppresses the sid2-1 sic1 Delta inviability, while stabilizing Clb5 protein exacerbates the defects of sid2-1 sic1 Delta cells. In synchronized sid2-1 mutant strains, the onset of replication appears normal, but completion of DNA synthesis is delayed. sid2-1 mutants are sensitive to hydroxyurea indicating that sid2-1 cells may suffer DNA damage that, when combined with additional insult, leads to a decrease in viability. Consistent with this hypothesis, sid2-1 rad9 cells are dead or very slow growing even when SIC1 is expressed. PMID:11560884
Legrand, Melanie; Chan, Christine L.; Jauert, Peter A.; Kirkpatrick, David T.
2011-01-01
Genome rearrangements, a common feature of Candida albicans isolates, are often associated with the acquisition of antifungal drug resistance. In Saccharomyces cerevisiae, perturbations in the S-phase checkpoints result in the same sort of Gross Chromosomal Rearrangements (GCRs) observed in C. albicans. Several proteins are involved in the S. cerevisiae cell cycle checkpoints, including Mec1p, a protein kinase of the PIKK (phosphatidyl inositol 3-kinase-like kinase) family and the central player in the DNA damage checkpoint. Sgs1p, the ortholog of BLM, the Bloom’s syndrome gene, is a RecQ-related DNA helicase; cells from BLM patients are characterized by an increase in genome instability. Yeast strains bearing deletions in MEC1 or SGS1 are viable (in contrast to the inviability seen with loss of MEC1 in S. cerevisiae) but the different deletion mutants have significantly different phenotypes. The mec1Δ/Δ colonies have a wild-type colony morphology, while the sgs1Δ/Δ mutants are slow-growing, producing wrinkled colonies with pseudohyphal-like cells. The mec1Δ/Δ mutants are only sensitive to ethylmethane sulfonate (EMS), methylmethane sulfonate (MMS), and hydroxyurea (HU) but the sgs1Δ/Δ mutants exhibit a high sensitivity to all DNA-damaging agents tested. In an assay for chromosome 1 integrity, the mec1Δ/Δ mutants exhibit an increase in genome instability; no change was observed in the sgs1Δ/Δ mutants. Finally, loss of MEC1 does not affect sensitivity to the antifungal drug fluconazole, while loss of SGS1 leads to an increased susceptibility to fluconazole. Neither deletion elevated the level of antifungal drug resistance acquisition. PMID:21511048
O’Konek, Jessica J.; Ladd, Brendon; Flanagan, Sheryl A.; Im, Mike M.; Boucher, Paul D.; Thepsourinthone, Tico S.; Secrist, John A.; Shewach, Donna S.
2011-01-01
Nucleoside analogs are efficacious cancer chemotherapeutics due to their incorporation into tumor cell DNA. However, they exhibit vastly different antitumor efficacies, suggesting that incorporation produces divergent effects on DNA replication. Here we have evaluated the consequences of incorporation on DNA replication and its fidelity for three structurally related deoxyguanosine analogs: ganciclovir (GCV), currently in clinical trials in a suicide gene therapy approach for cancer, D-carbocyclic 2′-deoxyguanosine (CdG) and penciclovir (PCV). GCV and CdG elicited similar cytotoxicity at low concentrations, whereas PCV was 10–100-fold less cytotoxic in human tumor cells. DNA replication fidelity was evaluated using a supF plasmid-based mutation assay. Only GCV induced a dose-dependent increase in mutation frequency, predominantly GC→TA transversions, which contributed to cytotoxicity and implicated the ether oxygen in mutagenicity. Activation of mismatch repair with hydroxyurea decreased mutations but failed to repair the GC→TA transversions. GCV slowed S-phase progression and CdG also induced a G2/M block, but both drugs allowed completion of one cell cycle after drug treatment followed by cell death in the second cell cycle. In contrast, PCV induced a lengthy early S-phase block due to profound suppression of DNA synthesis, with cell death in the first cell cycle after drug treatment. These data suggest that GCV and CdG elicit superior cytotoxicity due to their effects in template DNA, whereas strong inhibition of nascent strand synthesis by PCV may protect against cytotoxicity. Nucleoside analogs based on the carbohydrate structures of GCV and CdG is a promising area for antitumor drug development. PMID:20004674
Ranallo, Lauren
Providing end-of-life care to children with cancer is most ideally achieved by initiating palliative care at the time of diagnosis, advocating for supportive care throughout the treatment trajectory, and implementing hospice care during the terminal phase. The guiding principles behind offering palliative care to pediatric oncology patients are the prioritization of providing holistic care and management of disease-based symptoms. Pediatric hematology-oncology nurses and clinicians have a unique responsibility to support the patient and family unit and foster a sense of hope, while also preparing the family for the prognosis and a challenging treatment trajectory that could result in the child's death. In order to alleviate potential suffering the child may experience, there needs to be an emphasis on supportive care and symptom management. There are barriers to implementing palliative care for children with cancer, including the need to clarify the palliative care philosophy, parental acknowledgement and acceptance of a child's disease and uncertain future, nursing awareness of services, perception of availability, and a shortage of research guidance. It is important for nurses and clinicians to have a clear understanding of the fundamentals of palliative and end-of-life care for pediatric oncology patients to receive the best care possible.
Hawkins-Walsh, Elizabeth; Berg, Mary; Docherty, Sharron; Lindeke, Linda; Gaylord, Nan; Osborn, Kristen
2011-01-01
The past decade has been marked by a gradual expansion of the traditional primary care role of the pediatric nurse practitioner (PNP) into practice arenas that call for more acute and critical care of children. The purpose of the study was to explore the educational programming needs of dual (combined) track PNP programs that prepare graduates to provide care to children and adolescents across the continuum of health and illness. A two-phase, exploratory, mixed method design was utilized. An electronic survey was completed by 65% of PNP program directors in the country. Semi-structured telephone interviews were conducted with hospital-based PNPs who were practicing in roles that met a range of health care needs across the primary and acute care continuum. Primary care and acute care programs have more common than unique elements, and the vast majority of clinical competencies are common to both types of program. Only three competencies appear to be unique to acute care programs. The Association of Faculties of Pediatric Nurse Practitioner Programs should utilize existing evidence and develop guidelines for dual PNP programs that focus on the provision of care to children across a wide continuum of health and illness. Copyright © 2011 National Association of Pediatric Nurse Practitioners. Published by Mosby, Inc. All rights reserved.
2010-09-01
Although there are some interactions between the major pediatric diabetes programs in the United States, there has been no formal, independent structure for collaboration, the sharing of information, and the development of joint research projects that utilize common outcome measures. To fill this unmet clinical and research need, a consortium of seven pediatric diabetes centers in the United States has formed the Pediatric Diabetes Consortium (PDC) through an unrestricted grant from Novo Nordisk, Inc. (Princeton, NJ). This article describes the organizational structure of the PDC and the design of a study of important clinical outcomes in children and adolescents with new-onset, type 1 diabetes mellitus (T1DM). The outcomes study will describe the changes in A1c levels, the frequency of adverse events (diabetic ketoacidosis/severe hypoglycemia), and the frequency and timing of the "honeymoon" phase in newly diagnosed patients with T1DM over the first 12-24 months of the disease and examine the relationship between these clinical outcomes and demographic, socioeconomic, and treatment factors. This project will also allow the Consortium to develop a cohort of youth with T1DM whose clinical course has been well characterized and who wish to participate in future clinical trials and/or contribute to a repository of biological samples.
Pediatric Acute Kidney Injury.
Fragasso, Tiziana; Ricci, Zaccaria; Goldstein, Stuart L
2018-01-01
Acute kidney injury (AKI) in children is a serious condition with an important impact on morbidity and mortality. Onset can be insidious and it is frequently unrecognized in the early phase when the therapeutic opportunities are theoretically more effective. The present review focuses on the most recent epidemiology studies and the progress in pediatric AKI (pAKI) research. Standardization of definition (presented in the Kidney Disease: Improving Global Outcomes) and novel biomarkers have been developed to help clinicians recognize kidney injury in a timely manner, both in adult and pediatric populations. Strengths and weaknesses of these diagnostic tools are discussed and the clinical scoring system (Renal Angina Index), which aims to provide a rational context for biomarker utilization, is also presented. Even if effective treatments are not currently available for established AKI, specific preventive approaches and some promising pharmacological treatments will be detailed. Renal replacement therapy is currently considered the most effective way to manage fluid balance when severe AKI occurs. Key Messages: Great efforts in pAKI research have today led to new strategies for early AKI detection and prevention strategies. Further studies have to be conducted in the next future in order to definitely improve the outcomes of pediatric patients experiencing this deadly syndrome. © 2018 S. Karger AG, Basel.
Teaching Ethics to Pediatric Residents: A Literature Analysis and Synthesis.
Martakis, K; Czabanowska, K; Schröder-Bäck, P
2016-09-01
Ethics education rarely exists in pediatric resident curricula, although ethical conflicts are common in the clinical practice. Ethics education can prepare residents to successfully handle these conflicts. We searched for methods in teaching ethics to clinical and especially pediatric residents, and identified recurring barriers to ethics teaching and solutions to overcome them. Literature from 4 electronic databases with peer-reviewed articles was screened in 3 phases and analyzed. The literature included papers referring to applied methods or recommendations to teaching ethics to clinical residents, and on a second level focusing especially on pediatrics. An analysis and critical appraisal was conducted. 3 231 articles were identified. 96 papers were included. The applied learning theory, the reported teaching approaches, the barriers to teaching ethics and the provided solutions were studied and analyzed. We recommend case-based ethics education, including lectures, discussion, individual study; regular teaching sessions in groups, under supervision; affiliation to an ethics department, institutional and departmental support; ethics rounds and consultations not as core teaching activity; recurring problems to teaching ethics, primarily deriving from the complexity of residential duties to be addressed in advance; teaching ethics preferably in the first years of residency. We may be cautious generalizing the implementation of results on populations with different cultural backgrounds. © Georg Thieme Verlag KG Stuttgart · New York.
Coagulopathy and transfusion therapy in pediatric liver transplantation
Nacoti, Mirco; Corbella, Davide; Fazzi, Francesco; Rapido, Francesca; Bonanomi, Ezio
2016-01-01
Bleeding and coagulopathy are critical issues complicating pediatric liver transplantation and contributing to morbidity and mortality in the cirrhotic child. The complexity of coagulopathy in the pediatric patient is illustrated by the interaction between three basic models. The first model, “developmental hemostasis”, demonstrates how a different balance between pro- and anticoagulation factors leads to a normal hemostatic capacity in the pediatric patient at various ages. The second, the “cell based model of coagulation”, takes into account the interaction between plasma proteins and cells. In the last, the concept of “rebalanced coagulation” highlights how the reduction of both pro- and anticoagulation factors leads to a normal, although unstable, coagulation profile. This new concept has led to the development of novel techniques used to analyze the coagulation capacity of whole blood for all patients. For example, viscoelastic methodologies are increasingly used on adult patients to test hemostatic capacity and to guide transfusion protocols. However, results are often confounding or have limited impact on morbidity and mortality. Moreover, data from pediatric patients remain inadequate. In addition, several interventions have been proposed to limit blood loss during transplantation, including the use of antifibrinolytic drugs and surgical techniques, such as the piggyback and lowering the central venous pressure during the hepatic dissection phase. The rationale for the use of these interventions is quite solid and has led to their incorporation into clinical practice; yet few of them have been rigorously tested in adults, let alone in children. Finally, the postoperative period in pediatric cohorts of patients has been characterized by an enhanced risk of hepatic vessel thrombosis. Thrombosis in fact remains the primary cause of early graft failure and re-transplantation within the first 30 d following surgery, and it occurs despite prolongation of standard coagulation assays. Data, however, are currently lacking regarding the use of anti-aggregation/anticoagulation therapies and how to best monitor for thrombosis in the early postoperative period in pediatric patients. Therefore, further studies are necessary to elucidate the interaction between the development of the coagulation system and cirrhosis in children. Moreover, strategies to optimize blood transfusion and anticoagulation must be tested specifically in pediatric patients. In conclusion, data from the adult world can be translated with difficulty into the pediatric field as indication for transplantation, baseline pathologies and levels of pro- and anticoagulation factors are not comparable between the two populations. PMID:26877606
ERIC Educational Resources Information Center
Greenhill, Laurence L.; Muniz, Rafael; Ball, Roberta R.; Levine, Alan; Pestreich, Linda; Jiang, Hai
2006-01-01
Objective: The efficacy and safety of dexmethylphenidate extended release (d-MPH-ER) was compared to placebo in pediatric patients with attention-deficit/hyperactivity disorder (ADHD). Method: This multicenter, randomized, double-blind, placebo-controlled, parallel-group, two-phase study included 97 patients (ages 6-17 years) with…
von Stackelberg, Arend; Locatelli, Franco; Zugmaier, Gerhard; Handgretinger, Rupert; Trippett, Tanya M; Rizzari, Carmelo; Bader, Peter; O'Brien, Maureen M; Brethon, Benoît; Bhojwani, Deepa; Schlegel, Paul Gerhardt; Borkhardt, Arndt; Rheingold, Susan R; Cooper, Todd Michael; Zwaan, Christian M; Barnette, Phillip; Messina, Chiara; Michel, Gérard; DuBois, Steven G; Hu, Kuolung; Zhu, Min; Whitlock, James A; Gore, Lia
2016-12-20
Purpose Blinatumomab is a bispecific T-cell engager antibody construct targeting CD19 on B-cell lymphoblasts. We evaluated the safety, pharmacokinetics, recommended dosage, and potential for efficacy of blinatumomab in children with relapsed/refractory B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Methods This open-label study enrolled children < 18 years old with relapsed/refractory BCP-ALL in a phase I dosage-escalation part and a phase II part, using 6-week treatment cycles. Primary end points were maximum-tolerated dosage (phase I) and complete remission rate within the first two cycles (phase II). Results We treated 49 patients in phase I and 44 patients in phase II. Four patients had dose-limiting toxicities in cycle 1 (phase I). Three experienced grade 4 cytokine-release syndrome (one attributed to grade 5 cardiac failure); one had fatal respiratory failure. The maximum-tolerated dosage was 15 µg/m 2 /d. Blinatumomab pharmacokinetics was linear across dosage levels and consistent among age groups. On the basis of the phase I data, the recommended blinatumomab dosage for children with relapsed/refractory ALL was 5 µg/m 2 /d for the first 7 days, followed by 15 µg/m 2 /d thereafter. Among the 70 patients who received the recommended dosage, 27 (39%; 95% CI, 27% to 51%) achieved complete remission within the first two cycles, 14 (52%) of whom achieved complete minimal residual disease response. The most frequent grade ≥ 3 adverse events were anemia (36%), thrombocytopenia (21%), and hypokalemia (17%). Three patients (4%) and one patient (1%) had cytokine-release syndrome of grade 3 and 4, respectively. Two patients (3%) interrupted treatment after grade 2 seizures. Conclusion This trial, which to the best of our knowledge was the first such trial in pediatrics, demonstrated antileukemic activity of single-agent blinatumomab with complete minimal residual disease response in children with relapsed/refractory BCP-ALL. Blinatumomab may represent an important new treatment option in this setting, requiring further investigation in curative indications.
Alteraciones puberales en adolescentes con leucemia en fase de vigilancia.
Arriaga-Cázares, Héctor Eliud; Cázares-Bellazetin, Mara Alejandra; Sánchez-Sánchez, Luz María; Bahena-García, Ana Laura; Palacios-Saucedo, Gerardo Del Carmen
2017-01-01
To evaluate which factors are associated with alterations in pubertal development in pediatric patients with leukemia in the surveillance phase. A case-control study was carried out, including patients aged 8-14 years with diagnosis of acute lymphoblastic leukemia under surveillance. Demographic data were collected, age at diagnosis, type of leukemia, risk of leukemia, duration and type of treatment received, time of surveillance phase; and pubertal development was assessed by Tanner stage, bone age, pelvic ultrasound for women, and LH levels. Fisher's exact test and Mann-Whitney U-test were used. Twenty-five pediatric patients with a diagnosis of acute lymphoblastic leukemia between 8 and 14 years of age with a median of 8 were included, only 4 (16%) presented pubertal alterations, 1 had pubertal delay and 3 advanced puberty. The history of radiotherapy was related to pubertal alterations (p = 0.03). The antecedent of having received radiotherapy as part of the treatment in patients with acute lymphoblastic leukemia is a risk factor for developing pubertal abnormalities. Copyright: © 2017 SecretarÍa de Salud
Rohan, Jennifer M; Drotar, Dennis; Alderfer, Melissa; Donewar, Crista Wetherington; Ewing, Linda; Katz, Ernest R; Muriel, Anna
2015-01-01
To describe patterns of treatment adherence to early maintenance phase therapy for acute lymphoblastic leukemia (ALL) and lymphoblastic lymphoma (LBL). Using an objective observational method (electronic monitoring), adherence was examined for 139 patients aged 7-19 years diagnosed with ALL or LBL across 6 centers. The mean adherence percentage was 86.2%. Adherence rates declined over the 1-month of follow-up to 83%. 3 linear trajectories of 6-mercaptopurine adherence were identified: (1) exemplary adherence (n = 99): Averaging nearly 100%; (2) deteriorating (n = 23): Adherence decreased from 100 to 60%; and (3) chronically poor adherence (n = 9): Averaging 40%. Adherence promotion interventions might be tailored to subgroups of patients who demonstrated problematic patterns of treatment adherence that could place them at risk for relapse. This research demonstrates the importance of using objective real-time measures of medication adherence for measuring and documenting adherence patterns. © The Author 2013. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.