Clinical Practice Guideline-Inconsistent Management of Fertility Preservation in Pediatric Cancer Patients in Community Settings: A Children's Oncology Group Study

Background: The primary objective was to measure adherence to clinical practice guideline (CPG) recommendations for fertility preservation (FP) in pediatric cancer patients treated in National Cancer Institute Community Oncology Research Program (NCORP) sites. Secondary objectives were to describe factors such as site size associated with CPG-inconsistent care delivery and cryopreservation completion. Methods: This retrospective, multicenter study included patients 15 to 21 years old with a first cancer diagnosis from January 2014 through December 2015 who were previously enrolled to a Children's Oncology Group (COG) study and received care at a participating NCORP site. Patients were randomly selected from a list generated by the COG for chart review by participating sites. Primary outcome was care delivery that was inconsistent with a strong CPG recommendation on FP, namely discussion and offering of FP options before cancer treatment initiation, as adjudicated centrally by a panel. Results: A total of 129 patients from 25 sites were included. Among these, 48% (62/129) received CPG-inconsistent care. Most CPG-inconsistent care was due to lack of FP discussion documentation (93.5%, 58/62). Small site size, treatment at a pediatric (vs mixed adult/pediatric) site, and female sex were associated with higher odds of CPG-inconsistent care delivery. Conclusions: Newly diagnosed pediatric cancer patients often received CPG-inconsistent care for FP, with disproportionate gaps noted for females, and those treated at smaller or pediatric NCORP sites. The primary reason for CPG-inconsistent care is lack of FP discussion from clinicians. Opportunities to improve FP CPG implementation are highlighted.

Relevance of lymphocyte proliferation to PHA in severe combined immunodeficiency (SCID) and T cell lymphopenia

Severe combined immunodeficiency (SCID) is characterized by a severe deficiency in T cell numbers. We analyzed data collected (n = 307) for PHA-based T cell proliferation from the PIDTC SCID protocol 6901, using either a radioactive or flow cytometry method. In comparing the two groups, a smaller number of the patients tested by flow cytometry had <10% of the lower limit of normal proliferation as compared to the radioactive method (p = 0.02). Further, in patients with CD3+ T cell counts between 51 and 300 cells/μL, there was a higher proliferative response with the PHA flow assay compared to the 3H-T assay (p < 0.0001), suggesting that the method of analysis influences the resolution and interpretation of PHA results. Importantly, we observed many SCID patients with profound T cell lymphopenia having normal T cell proliferation when assessed by flow cytometry. We recommend this test be considered only as supportive in the diagnosis of typical SCID.

Posttransplantation late complications increase over time for patients with SCID: A Primary Immune Deficiency Treatment Consortium (PIDTC) landmark study

BACKGROUND

The Primary Immune Deficiency Treatment Consortium (PIDTC) enrolled children in the United States and Canada onto a retrospective multicenter natural history study of hematopoietic cell transplantation (HCT).

OBJECTIVE

We investigated outcomes of HCT for severe combined immunodeficiency (SCID).

METHODS

We evaluated the chronic and late effects (CLE) after HCT for SCID in 399 patients transplanted from 1982 to 2012 at 32 PIDTC centers. Eligibility criteria included survival to at least 2 years after HCT without need for subsequent cellular therapy. CLE were defined as either conditions present at any time before 2 years from HCT that remained unresolved (chronic), or new conditions that developed beyond 2 years after HCT (late).

RESULTS

The cumulative incidence of CLE was 25% in those alive at 2 years, increasing to 41% at 15 years after HCT. CLE were most prevalent in the neurologic (9%), neurodevelopmental (8%), and dental (8%) categories. Chemotherapy-based conditioning was associated with decreased-height z score at 2 to 5 years after HCT (P < .001), and with endocrine (P < .001) and dental (P = .05) CLE. CD4 count of ≤500 cells/μL and/or continued need for immunoglobulin replacement therapy >2 years after transplantation were associated with lower-height z scores. Continued survival from 2 to 15 years after HCT was 90%. The presence of any CLE was associated with increased risk of late death (hazard ratio, 7.21; 95% confidence interval, 2.71-19.18; P < .001).

CONCLUSION

Late morbidity after HCT for SCID was substantial, with an adverse impact on overall survival. This study provides evidence for development of survivorship guidelines based on disease characteristics and treatment exposure for patients after HCT for SCID.

Genotype, oxidase status, and preceding infection or autoinflammation do not affect allogeneic HCT outcomes for CGD

Chronic granulomatous disease (CGD) is a primary immunodeficiency characterized by life-threatening infections and inflammatory conditions. Hematopoietic cell transplantation (HCT) is the definitive treatment for CGD, but questions remain regarding patient selection and impact of active disease on transplant outcomes. We performed a multi-institutional retrospective and prospective study of 391 patients with CGD treated either conventionally (non-HCT) enrolled from 2004 to 2018 or with HCT from 1996 to 2018. Median follow-up after HCT was 3.7 years with a 3-year overall survival of 82% and event-free survival of 69%. In a multivariate analysis, a Lansky/Karnofsky score <90 and use of HLA-mismatched donors negatively affected survival. Age, genotype, and oxidase status did not affect outcomes. Before HCT, patients had higher infection density, higher frequency of noninfectious lung and liver diseases, and more steroid use than conventionally treated patients; however, these issues did not adversely affect HCT survival. Presence of pre-HCT inflammatory conditions was associated with chronic graft-versus-host disease. Graft failure or receipt of a second HCT occurred in 17.6% of the patients and was associated with melphalan-based conditioning and/or early mixed chimerism. At 3 to 5 years after HCT, patients had improved growth and nutrition, resolved infections and inflammatory disease, and lower rates of antimicrobial prophylaxis or corticosteroid use compared with both their baseline and those of conventionally treated patients. HCT leads to durable resolution of CGD symptoms and lowers the burden of the disease. Patients with active infection or inflammation are candidates for transplants; HCT should be considered before the development of comorbidities that could affect performance status. This trial was registered at www.clinicaltrials.gov as #NCT02082353.

Measuring the effect of newborn screening on survival after haematopoietic cell transplantation for severe combined immunodeficiency: a 36-year longitudinal study from the Primary Immune Deficiency Treatment Consortium

BACKGROUND

Severe combined immunodeficiency (SCID) is fatal unless durable adaptive immunity is established, most commonly through allogeneic haematopoietic cell transplantation (HCT). The Primary Immune Deficiency Treatment Consortium (PIDTC) explored factors affecting the survival of individuals with SCID over almost four decades, focusing on the effects of population-based newborn screening for SCID that was initiated in 2008 and expanded during 2010-18.

METHODS

We analysed transplantation-related data from children with SCID treated at 34 PIDTC sites in the USA and Canada, using the calendar time intervals 1982-89, 1990-99, 2000-09, and 2010-18. Categorical variables were compared by χ2 test and continuous outcomes by the Kruskal-Wallis test. Overall survival was estimated by the Kaplan-Meier method. A multivariable analysis using Cox proportional hazards regression models examined risk factors for HCT outcomes, including the variables of time interval of HCT, infection status and age at HCT, trigger for diagnosis, SCID type and genotype, race and ethnicity of the patient, non-HLA-matched sibling donor type, graft type, GVHD prophylaxis, and conditioning intensity.

FINDINGS

For 902 children with confirmed SCID, 5-year overall survival remained unchanged at 72%-73% for 28 years until 2010-18, when it increased to 87% (95% CI 82·1-90·6; n=268; p=0·0005). For children identified as having SCID by newborn screening since 2010, 5-year overall survival was 92·5% (95% CI 85·8-96·1), better than that of children identified by clinical illness or family history in the same interval (79·9% [69·5-87·0] and 85·4% [71·8-92·8], respectively [p=0·043]). Multivariable analysis demonstrated that the factors of active infection (hazard ratio [HR] 2·41, 95% CI 1·56-3·72; p<0·0001), age 3·5 months or older at HCT (2·12, 1·38-3·24; p=0·001), Black or African-American race (2·33, 1·56-3·46; p<0·0001), and certain SCID genotypes to be associated with lower overall survival during all time intervals. Moreover, after adjusting for several factors in this multivariable analysis, HCT after 2010 no longer conveyed a survival advantage over earlier time intervals studied (HR 0·73, 95% CI 0·43-1·26; p=0·097). This indicated that younger age and freedom from infections at HCT, both directly driven by newborn screening, were the main drivers for recent improvement in overall survival.

INTERPRETATION

Population-based newborn screening has facilitated the identification of infants with SCID early in life, in turn leading to prompt HCT while avoiding infections. Public health programmes worldwide can benefit from this definitive demonstration of the value of newborn screening for SCID.

FUNDING

National Institute of Allergy and Infectious Diseases, Office of Rare Diseases Research, and National Center for Advancing Translational Sciences.

Clinical practice guideline recommendation summaries for pediatric oncology health care professionals: A qualitative study

OBJECTIVE

To develop a summary format of clinical practice guideline (CPG) recommendations to improve understandability among health care professionals.

METHODS

We developed a summary format based on current research and used the "Think Aloud" technique in one-on-one cognitive interviews to iteratively improve it. Interviews of health care professionals from Children's Oncology Group-member, National Cancer Institute Community Oncology Research Program sites were conducted. After every five interviews (a round), responses were reviewed, and changes made to the format until it was well understood and no new, substantive suggestions for revision were raised. We took a directed (deductive) approach to content analysis of the interview notes to identify concerns related to recommendation summary usability, understandability, validity, applicability and visual appeal.

RESULTS

During seven rounds of interviews with 33 health care professionals, we identified important factors that influenced understandability. Participants found understanding weak recommendations more challenging than strong recommendations. Understanding was improved when the term 'conditional' recommendation was used instead of 'weak' recommendation. Participants found a Rationale section to be very helpful but desired more information when a recommendation entailed a practice change. In the final format, the recommendation strength is clearly indicated in the title, highlighted, and defined within a text box. The rationale for the recommendation is in a column on the left, with supporting evidence on the right. In a bulleted list, the Rationale section describes the benefits and harms and additional factors, such as implementation, that were considered by the CPG developers. Each bullet under the supporting evidence section indicates the level of evidence with an explanation and the supporting studies with hyperlinks when applicable.

CONCLUSIONS

A summary format to present strong and conditional recommendations was created through an iterative interview process. The format is straightforward, making it easy for organizations and CPG developers to use it to communicate recommendations clearly to intended users.

Comparison of hematopoietic cell transplant conditioning regimens for hemophagocytic lymphohistiocytosis disorders

BACKGROUND

Allogeneic hematopoietic cell transplantation for hemophagocytic lymphohistiocytosis (HLH) disorders is associated with substantial morbidity and mortality.

OBJECTIVE

The effect of conditioning regimen groups of varying intensity on outcomes after transplantation was examined to identify an optimal regimen or regimens for HLH disorders.

METHODS

We studied 261 patients with HLH disorders transplanted between 2005 and 2018. Risk factors for transplantation outcomes by conditioning regimen groups were studied by Cox regression models.

RESULTS

Four regimen groups were studied: (1) fludarabine (Flu) and melphalan (Mel) in 123 subjects; (2) Flu, Mel, and thiotepa (TT) in 28 subjects; (3) Flu and busulfan (Bu) in 14 subjects; and (4) Bu and cyclophosphamide (Cy) in 96 subjects. The day 100 incidence of veno-occlusive disease was lower with Flu/Mel (4%) and Flu/Mel/TT (0%) compared to Flu/Bu (14%) and Bu/Cy (22%) (P < .001). The 6-month incidence of viral infections was highest after Flu/Mel (72%) and Flu/Mel/TT (64%) compared to Flu/Bu (39%) and Bu/Cy (38%) (P < .001). Five-year event-free survival (alive and engrafted without additional cell product administration) was lower with Flu/Mel (44%) compared to Flu/Mel/TT (70%), Flu/Bu (79%), and Bu/Cy (61%) (P = .002). The corresponding 5-year overall survival values were 68%, 75%, 86%, and 64%, and did not differ by conditioning regimen (P = .19). Low event-free survival with Flu/Mel is attributed to high graft failure (42%) compared to Flu/Mel/TT (15%), Flu/Bu (7%), and Bu/Cy (18%) (P < .001).

CONCLUSIONS

Given the high rate of graft failure with Flu/Mel and the high rate of veno-occlusive disease with Bu/Cy and Flu/Bu, Flu/Mel/TT may be preferred for HLH disorders. Prospective studies are warranted.

Granulocyte Colony-Stimulating Factor is Safe and Well Tolerated following Allogeneic Transplantation in Patients with Sickle Cell Disease

Granulocyte colony-stimulating factor (G-CSF) used after hematopoietic stem cell transplantation (HSCT) can enhance neutrophil recovery in patients rendered neutropenic by the preparative regimen. G-CSF is contraindicated in patients with sickle cell disease (SCD) as life-threatening complications can ensue in the presence of sickle vasculopathy. However, the safety profile of G-CSF after HSCT for SCD has not been previously described. We report clinical outcomes in the first 100 days post-HSCT in patients supported with G-CSF until neutrophil recovery on a clinical trial of reduced intensity transplantation for SCD. Patients (n=62) received G-CSF for a median of 9 days (range, 5-33) following transplant from the best available stem cell source. Preparation for transplant included a target hemoglobin S level of ≤45%. Neutrophil engraftment (ANC >0.5 × 10³/mL) was achieved at a median of 13 days (range,10-34) and platelet engraftment (>50 × 10³/mL) at a median of 19 days (range, 12-71). The median duration of inpatient hospitalization following stem cell infusion (day 0) was 21.5 days (range 11-33). No patient developed SCD related complications following G-CSF use. The most common organ toxicities encountered between G-CSF commencement (on day +7) and day +100 were anorexia (14), hypertension (11) and electrolyte imbalance requiring correction (9). Central nervous system related events were noted in 5 patients, all with pre-existing cerebral vasculopathy/moyamoya disease and attributed to reversible posterior leukoencephalopathy syndrome (RPLS) in the presence of calcineurin inhibitor therapy and hypertension. We conclude that G-CSF does not adversely impact SCD transplant recipients and can be safely used post-HSCT to enhance neutrophil recovery.

Facilitators and barriers to clinical practice guideline-consistent supportive care at pediatric oncology institutions: a Children's Oncology Group study

Background

Clinical practice guideline (CPG)-consistent care improves patient outcomes, but CPG implementation is poor. Little is known about CPG implementation in pediatric oncology. This study aimed to understand supportive care CPG implementation facilitators and barriers at pediatric oncology National Cancer Institute (NCI) Community Oncology Research Program (NCORP) institutions.

Methods

Healthcare professionals at 26 pediatric, Children's Oncology Group-member, NCORP institutions were invited to participate in face-to-face focus groups. Serial focus groups were held until saturation of ideas was reached. Supportive care CPG implementation facilitators and barriers were solicited using nominal group technique (NGT), and implementation of specific supportive care CPG recommendations was discussed. Notes from each focus group were analyzed using a directed content analysis. The top five themes arising from an analysis of NGT items were identified, first from each focus group and then across all focus groups.

Results

Saturation of ideas was reached after seven focus groups involving 35 participants from 18 institutions. The top five facilitators of CPG implementation identified across all focus groups were organizational factors including charging teams with CPG implementation, individual factors including willingness to standardize care, user needs and values including mentorship, system factors including implementation structure, and implementation strategies including a basis in science. The top five barriers of CPG implementation identified were organizational factors including tolerance for inconsistencies, individual factors including lack of trust, system factors including administrative hurdles, user needs and values including lack of inclusivity, and professional including knowledge gaps.

Conclusions

Healthcare professionals at pediatric NCORP institutions believe that organizational factors are the most important determinants of supportive care CPG implementation. They believe that CPG-consistent supportive care is most likely to be delivered in organizations that prioritize evidence-based care, provide structure and resources to implement CPGs, and eliminate implementation barriers.

Trial registration

ClinicalTrials.gov Identifier: NCT02847130. Date of registration: July 28, 2016.

Supplementary Information

The online version contains supplementary material available at 10.1186/s43058-021-00200-2.

Chlorhexidine gluconate bathing in children with cancer or those undergoing hematopoietic stem cell transplantation: A double-blinded randomized controlled trial from the Children's Oncology Group

BACKGROUND

To the authors' knowledge, information regarding whether daily bathing with chlorhexidine gluconate (CHG) reduces central line-associated bloodstream infection (CLABSI) in pediatric oncology patients and those undergoing hematopoietic stem cell transplantation (HCT) is limited.

METHODS

In the current multicenter, randomized, double-blind, placebo-controlled trial, patients aged ≥2 months and <22 years with cancer or those undergoing allogeneic HCT were randomized 1:1 to once-daily bathing with 2% CHG-impregnated cloths or control cloths for 90 days. The primary outcome was CLABSI. Secondary endpoints included total positive blood cultures, acquisition of resistant organisms, and acquisition of cutaneous staphylococcal isolates with an elevated CHG mean inhibitory concentration.

RESULTS

The study was stopped early because of poor accrual. Among the 177 enrolled patients, 174 were considered as evaluable (88 were randomized to the CHG group and 86 were randomized to the control group). The rate of CLABSI per 1000 central line days in the CHG group was 5.44 versus 3.10 in the control group (risk difference, 2.37; 95% confidence interval, 0.05-4.69 [P = .049]). Post hoc conditional power analysis demonstrated a 0.2% chance that the results would have favored CHG had the study fully enrolled. The rate of total positive blood cultures did not differ between groups (risk difference, 2.37; 95% confidence interval, -0.41 to 5.14 [P = .078]). The number of patients demonstrating the new acquisition of resistant organisms did not differ between groups (P = .54). Patients in the CHG group were found to be more likely to acquire cutaneous staphylococcal isolates with an elevated CHG mean inhibitory concentration (P = .032).

CONCLUSIONS

The data from the current study do not support the use of routine CHG bathing in children with cancer or those undergoing allogeneic HCT.

Correction: Chronic Granulomatous Disease-Associated IBD Resolves and Does Not Adversely Impact Survival Following Allogeneic HCT

The original version of this article unfortunately contained the missing author, Caridad Martinez. The authors would like to correct the list. We apologize for any inconvenience that this may have caused. The correct author list is shown above.

Infections in Infants with SCID: Isolation, Infection Screening, and Prophylaxis in PIDTC Centers

PURPOSE

The Primary Immune Deficiency Treatment Consortium (PIDTC) enrolled children with severe combined immunodeficiency (SCID) in a prospective natural history study of hematopoietic stem cell transplant (HSCT) outcomes over the last decade. Despite newborn screening (NBS) for SCID, infections occurred prior to HSCT. This study's objectives were to define the types and timing of infection prior to HSCT in patients diagnosed via NBS or by family history (FH) and to understand the breadth of strategies employed at PIDTC centers for infection prevention.

METHODS

We analyzed retrospective data on infections and pre-transplant management in patients with SCID diagnosed by NBS and/or FH and treated with HSCT between 2010 and 2014. PIDTC centers were surveyed in 2018 to understand their practices and protocols for pre-HSCT management.

RESULTS

Infections were more common in patients diagnosed via NBS (55%) versus those diagnosed via FH (19%) (p = 0.012). Outpatient versus inpatient management did not impact infections (47% vs 35%, respectively; p = 0.423). There was no consensus among PIDTC survey respondents as to the best setting (inpatient vs outpatient) for pre-HSCT management. While isolation practices varied, immunoglobulin replacement and antimicrobial prophylaxis were more uniformly implemented.

CONCLUSION

Infants with SCID diagnosed due to FH had lower rates of infection and proceeded to HSCT more quickly than did those diagnosed via NBS. Pre-HSCT management practices were highly variable between centers, although uses of prophylaxis and immunoglobulin support were more consistent. This study demonstrates a critical need for development of evidence-based guidelines for the pre-HSCT management of infants with SCID following an abnormal NBS.

TRIAL REGISTRATION

NCT01186913.

Impact of T Cell Dose on Outcome of T Cell-Replete HLA-Matched Allogeneic Peripheral Blood Stem Cell Transplantation

Data on whether the T cell dose of allogeneic peripheral blood stem cell (PBSC) products influences transplantation outcomes are conflicting. Using the Center for International Blood and Marrow Transplant Research database, we identified 2736 adult patients who underwent first allogeneic PBSC transplantation for acute leukemia or myelodysplastic syndrome between 2008 and 2014 using an HLA-matched sibling donor (MSD) or an 8/8-matched unrelated donor (MUD). We excluded ex vivo and in vivo T cell-depleted transplantations. Correlative analysis was performed between CD3+ T cell dose and the risk of graft-versus-host-disease (GVHD), relapse, nonrelapse mortality (NRM), disease-free survival (DFS), and overall survival (OS). Using maximum likelihood estimation, we identified CD3+ T cell dose cutoff that separated the risk of acute GVHD (aGVHD) grade II-IV in both the MSD and MUD groups. A CD3+ T cell dose cutoff of 14 × 107 cells/kg identified MSD/low CD3+ (n = 223) and MSD/high CD3+ (n = 1214), and a dose of 15 × 107 cells/kg identified MUD/low CD3+ (n = 197) and MUD/high CD3+ (n = 1102). On univariate analysis, the MSD/high CD3+ group had a higher cumulative incidence of day +100 aGVHD grade II-IV compared with the MSD/low CD3+ group (33% versus 25%; P = .009). There were no differences between the 2 groups in engraftment rate, risk of aGVHD grade III-IV or chronic GVHD (cGVHD), NRM, relapse, DFS, or OS. The MUD/high CD3+ group had a higher cumulative incidence of day +100 aGVHD grade II-IV compared with the MUD/low CD3+ group (49% versus 41%; P = .04). There were no differences between the 2 groups in engraftment rate, risk of severe aGVHD or cGVHD, NRM, relapse, DFS, or OS. Multivariate analysis of the MSD and MUD groups failed to show an association between CD3+ T cell dose and the risk of either aGVHD grade II-IV (P = .10 and .07, respectively) or cGVHD (P = .80 and .30, respectively). Subanalysis of CD4+ T cells, CD8+ T cells, and CD4+/CD8+ ratio failed to identify cutoff values predictive of transplantation outcomes; however, using the log-rank test, the sample size was suboptimal for identifying a difference at this cutoff cell dose. In this registry study, the CD3+ T cell dose of PBSC products did not influence the risk of aGVHD or cGVHD or other transplantation outcomes when using an MSD or an 8/8-matched MUD. Subset analyses of CD4+ and CD8+ T cell doses were not possible given our small sample size.

SCID genotype and 6-month posttransplant CD4 count predict survival and immune recovery

The Primary Immune Deficiency Treatment Consortium (PIDTC) performed a retrospective analysis of 662 patients with severe combined immunodeficiency (SCID) who received a hematopoietic cell transplantation (HCT) as first-line treatment between 1982 and 2012 in 33 North American institutions. Overall survival was higher after HCT from matched-sibling donors (MSDs). Among recipients of non-MSD HCT, multivariate analysis showed that the SCID genotype strongly influenced survival and immune reconstitution. Overall survival was similar for patients with RAG, IL2RG, or JAK3 defects and was significantly better compared with patients with ADA or DCLRE1C mutations. Patients with RAG or DCLRE1C mutations had poorer immune reconstitution than other genotypes. Although survival did not correlate with the type of conditioning regimen, recipients of reduced-intensity or myeloablative conditioning had a lower incidence of treatment failure and better T- and B-cell reconstitution, but a higher risk for graft-versus-host disease, compared with those receiving no conditioning or immunosuppression only. Infection-free status and younger age at HCT were associated with improved survival. Typical SCID, leaky SCID, and Omenn syndrome had similar outcomes. Landmark analysis identified CD4+ and CD4+CD45RA+ cell counts at 6 and 12 months post-HCT as biomarkers predictive of overall survival and long-term T-cell reconstitution. Our data emphasize the need for patient-tailored treatment strategies depending upon the underlying SCID genotype. The prognostic significance of CD4+ cell counts as early as 6 months after HCT emphasizes the importance of close follow-up of immune reconstitution to identify patients who may need additional intervention to prevent poor long-term outcome.

Survival and Late Effects after Allogeneic Hematopoietic Cell Transplantation for Hematologic Malignancy at Less than Three Years of Age

Very young children undergoing hematopoietic cell transplantation (HCT) are a unique and vulnerable population. We analyzed outcomes of 717 patients from 117 centers who survived relapse free for ≥1 year after allogeneic myeloablative HCT for hematologic malignancy at <3 years of age, between 1987 and 2012. The median follow-up was 8.3 years (range, 1.0 to 26.4 years); median age at follow-up was 9 years (range, 2 to 29 years). Ten-year overall and relapse-free survival were 87% (95% confidence interval [CI], 85% to 90%) and 84% (95% CI, 81% to 87%). Ten-year cumulative incidence of relapse was 11% (95% CI, 9% to 13%). Of 84 deaths, relapse was the leading cause (43%). Chronic graft-versus-host-disease 1 year after HCT was associated with increased risk of mortality (hazard ratio [HR], 2.1; 95% CI, 1.3 to 3.3; P = .0018). Thirty percent of patients experienced ≥1 organ toxicity/late effect >1 year after HCT. The most frequent late effects included growth hormone deficiency/growth disturbance (10-year cumulative incidence, 23%; 95% CI, 19% to 28%), cataracts (18%; 95% CI, 15% to 22%), hypothyroidism (13%; 95% CI, 10% to 16%), gonadal dysfunction/infertility requiring hormone replacement (3%; 95% CI, 2% to 5%), and stroke/seizure (3%; 95% CI, 2% to 5%). Subsequent malignancy was reported in 3.6%. In multivariable analysis, total body irradiation (TBI) was predictive of increased risk of cataracts (HR, 17.2; 95% CI, 7.4 to 39.8; P < .001), growth deficiency (HR, 3.5; 95% CI, 2.2 to 5.5; P < .001), and hypothyroidism (HR, 5.3; 95% CI, 3.0 to 9.4; P < .001). In summary, those who survived relapse free ≥1 year after HCT for hematologic malignancy at <3 years of age had favorable overall survival. Chronic graft-versus-host-disease and TBI were associated with adverse outcomes. Future efforts should focus on reducing the risk of relapse and late effects after HCT at early age.

Protein tyrosine kinase regulates α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor trafficking induced by acute hypoxia in cultured brainstem neurons

This study was performed to investigate the modulation effect of protein tyrosine kinase on postsynaptic a-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor trafficking induced by acute hypoxia in cultured brainstem neurons. The cultured neurons were exposed to 1% O2 and the expression of AMPA receptor subunit GluR2 on the cell surface was significantly increased, while total GluR2 was not markedly changed. Furthermore, the hypoxia-induced increase in GluR2 expression on the cell surface was partially blocked by the protein tyrosine kinase membrane-permeable inhibitor genistein. In contrast, both the protein tyrosine kinase agonist nerve growth factor and protein tyrosine phosphatase inhibitor vanadate promoted the hypoxia-induced increase of GluR2 expression on cell surface. Moreover, GluR2 could be phosphorylated by tyrosine under normoxia and hypoxia conditions in vitro on brainstem neurons, and tyrosine phosphorylation of GluR2 was significantly stronger under hypoxia conditions. Our results indicate that acute hypoxia induces the AMPA receptor subunit GluR2 to rapidly migrate to the cell membrane to modify the strength of the synapse. This study indicates that tyrosine phosphorylation of the receptor is an important pathway regulating the rapid migration of GluR2 in the postsynaptic domain induced by hypoxia.

Daily Bathing with Chlorhexidine and Its Effects on Nosocomial Infection Rates in Pediatric Oncology Patients

Infections remain a serious complication in pediatric oncology patients. To determine if daily bathing with Chlorhexidine gluconate can decrease the rate of nosocomial infection in pediatric oncology patients, we reviewed rates of infections in pediatric oncology patients over a 14-month span. Intervention group received daily bath with Chlorhexidine, while the control group did not receive daily bath. The results showed that daily bath with antiseptic chlorhexidine as daily prophylactic antiseptic topical wash leads to decreased infection density amongst the pediatric oncology patients, especially in patients older than 12 years of age. Furthermore, daily chlorhexidine bathing significantly reduced the rate of hospital acquired infection in patients older than 12 years of age. The findings of this study suggest that daily bathing with chlorhexidine may be an effective measure of reducing nosocomial infection in pediatric oncology patients.

Long-term survival and late effects among one-year survivors of second allogeneic hematopoietic cell transplantation for relapsed acute leukemia and myelodysplastic syndromes

We analyzed the outcomes of patients who survived disease-free for 1 year or more after a second allogeneic hematopoietic cell transplantation (HCT) for relapsed acute leukemia or myelodysplastic syndromes between 1980 and 2009. A total of 1285 patients received a second allogeneic transplant after disease relapse; among these, 325 were relapse free at 1 year after the second HCT. The median time from first to second HCT was 17 and 24 months for children and adults, respectively. A myeloablative preparative regimen was used in the second transplantation in 62% of children and 45% of adult patients. The overall 10-year conditional survival rates after second transplantation in this cohort of patients who had survived disease-free for at least 1 year was 55% in children and 39% in adults. Relapse was the leading cause of mortality (77% and 54% of deaths in children and adults, respectively). In multivariate analyses, only disease status before second HCT was significantly associated with higher risk for overall mortality (hazard ratio, 1.71 for patients with disease not in complete remission before second HCT, P < .01). Chronic graft-versus-host disease (GVHD) developed in 43% and 75% of children and adults after second transplantation. Chronic GVHD was the leading cause of nonrelapse mortality, followed by organ failure and infection. The cumulative incidence of developing at least 1 of the studied late effects within 10 years after second HCT was 63% in children and 55% in adults. The most frequent late effects in children were growth disturbance (10-year cumulative incidence, 22%) and cataracts (20%); in adults they were cataracts (20%) and avascular necrosis (13%). Among patients with acute leukemia and myelodysplastic syndromes who receive a second allogeneic HCT for relapse and survive disease free for at least 1 year, many can be expected to survive long term. However, they continue to be at risk for relapse and nonrelapse morbidity and mortality. Novel approaches are needed to minimize relapse risk and long-term transplantation morbidity in this population.

Energy and redox States in the c6 glioma cells following acute exposure to zn, se(+4), and se(+6) and the correlation with apoptosis

Changes in cellular energy and redox states in the C6 glioma cells exposed to increasing concentrations of either Zn or Se were studied to examine whether different elements cause different patterns of changes in cellular metabolism. Following a 3-h exposure, both Zn and Se(+4) caused dose-dependent decreases in cell viability and total adenosine nucleotides (TAN = ATP + ADP + AMP). In addition, Zn caused a dose-dependent increase in cellular ATP/TAN and a decrease in the ADP/TAN and AMP/TAN. These changes resulted in a significant increase in energy charge potential (ECP = [ATP + 0.5ADP]/TAN). Se(+4), on the other hand, caused a dose-dependent decrease in ATP/TAN but an increase in both ADP/TAN and AMP/TAN, resulting in a dose-dependent decrease in ECP. Both Zn and Se(+4) caused a dose-dependent decrease in GSH/GSSG and an increase in GSH + GSSG when compared to TAN. In contrast to Zn and Se(+4), the nontoxic Se(+6) caused no significant changes in cellular energy states but reduced the GSH/GSSG ratio from 3.14 +/- 0.49 to 2.05 +/- 0.29, which could be explained by the effect of Se on enzymes responsible for GSH metabolism. As the cellular ATP level has been considered an important element that mediates the mode of cell death, it was suggested that a significant increase in ATP/TAN upon exposure to Zn would indicate that cell death occurred via apoptosis, while Se(+4) caused a different pattern of cell death. This was confirmed by the appearance of cells with fragmented nucleus in cells treated with Zn, but not Se(+4) and Se(+6). The results demonstrated that different chemicals caused different patterns of metabolic changes. The correlation between metabolic changes and the mode of cell death was discussed.

Late effects in hematopoietic cell transplant recipients with acquired severe aplastic anemia: a report from the late effects working committee of the center for international blood and marrow transplant research

With improvements in hematopoietic cell transplant (HCT) outcomes for severe aplastic anemia (SAA), there is a growing population of SAA survivors after HCT. However, there is a paucity of information regarding late effects that occur after HCT in SAA survivors. This study describes the malignant and nonmalignant late effects in survivors with SAA after HCT. A descriptive analysis was conducted of 1718 patients post-HCT for acquired SAA between 1995 and 2006 reported to the Center for International Blood and Marrow Transplant Research (CIBMTR). The prevalence and cumulative incidence estimates of late effects are reported for 1-year HCT survivors with SAA. Of the HCT recipients, 1176 (68.5%) and 542 (31.5%) patients underwent a matched sibling donor (MSD) or unrelated donor (URD) HCT, respectively. The median age at the time of HCT was 20 years. The median interval from diagnosis to transplantation was 3 months for MSD HCT and 14 months for URD HCT. The median follow-up was 70 months and 67 months for MSD and URD HCT survivors, respectively. Overall survival at 1 year, 2 years, and 5 years for the entire cohort was 76% (95% confidence interval [CI]: 74-78), 73% (95% CI: 71-75), and 70% (95% CI: 68-72). Among 1-year survivors of MSD HCT, 6% had 1 late effect and 1% had multiple late effects. For 1-year survivors of URD HCT, 13% had 1 late effect and 2% had multiple late effects. Among survivors of MSD HCT, the cumulative incidence estimates of developing late effects were all <3% and did not increase over time. In contrast, for recipients of URD HCT, the cumulative incidence of developing several late effects exceeded 3% by 5 years: gonadal dysfunction 10.5% (95% CI: 7.3-14.3), growth disturbance 7.2% (95% CI: 4.4-10.7), avascular necrosis 6.3% (95% CI: 3.6-9.7), hypothyroidism 5.5% (95% CI: 2.8-9.0), and cataracts 5.1% (95% CI: 2.9-8.0). Our results indicated that all patients undergoing HCT for SAA remain at risk for late effects, must be counseled about, and should be monitored for late effects for the remainder of their lives.

A facile, branched DNA assay to quantitatively measure glucocorticoid receptor auto-regulation in T-cell acute lymphoblastic leukemia

Glucocorticoid (GC) steroid hormones are used to treat acute lymphoblastic leukemia (ALL) because of their pro-apoptotic effects in hematopoietic cells. However, not all leukemia cells are sensitive to GC, and no assay to stratify patients is available. In the GC-sensitive T-cell ALL cell line CEM-C7, auto-up-regulation of RNA transcripts for the glucocorticoid receptor (GR) correlates with increased apoptotic response. This study aimed to determine if a facile assay of GR transcript levels might be promising for stratifying ALL patients into hormone-sensitive and hormone-resistant populations. The GR transcript profiles of various lymphoid cell lines and 4 bone marrow samples from patients with T-cell ALL were analyzed using both an optimized branched DNA (bDNA) assay and a real-time quantitative reverse transcription-polymerase chain reaction assay. There were significant correlations between both assay platforms when measuring total GR (exon 5/6) transcripts in various cell lines and patient samples, but not for a probe set that detects a specific, low abundance GR transcript (exon 1A3). Our results suggest that the bDNA platform is reproducible and precise when measuring total GR transcripts and, with further development, may ultimately offer a simple clinical assay to aid in the prediction of GC-sensitivity in ALL patients.

State-dependent radial elasticity of attached cross-bridges in single skinned fibres of rabbit psoas muscle

1. In a single skinned fibre of rabbit psoas muscle, upon attachment of cross-bridges to actin in the presence of ADP or pyrophosphate (PP(i)), the separation between the contractile filaments, as determined by equatorial X-ray diffraction, is found to decrease, suggesting that force is generated in the radial direction.2. The single muscle fibres were subjected to compression by 0-8% of dextran T(500). The changes in lattice spacings by dextran compression were compared with changes induced by cross-bridge attachment to actin. Based on this comparison, the magnitude and the direction of the radial force generated by the attached cross-bridges were estimated. The radial cross-bridge force varied with filament separation, and the magnitude of the radial cross-bridge force reached as high as the maximal axial force produced during isometric contraction.3. One key parameter of the radial elasticity, i.e. the equilibrium spacing where the radial force is zero, was found to depend on the ligand bound to the myosin head. In the presence of ADP, the equilibrium spacing was 36 nm. In the presence of MgPP(i) the equilibrium spacing shifted to 35 nm and Ca(2+) had little effect on the equilibrium spacing.4. The equilibrium spacing was independent of the fraction of cross-bridges attached to actin. The fraction of cross-bridges attached in rigor was modulated from 100% to close to 0% by adding up to 10 mM of ATPgammaS in the rigor solution. The lattice spacing remained at 38 nm, the equilibrium spacing for nucleotide-free cross-bridges at mu = 170 mM.5. Radial force generated by cross-bridges in rigor at large lattice spacings (38 nm </= d(10) </= 46 nm) appeared to vary linearly with lattice spacing.6. The titration of ATPgammaS to fibres in rigor provided a correlation between the radial stiffness of the nucleotide-free cross-bridges and the equatorial intensities. The relation between the equatorial intensity ratio I(11)/I(10) and radial stiffness appeared to be approximately linear.7. The fibres under different conditions showed a wide range of radial stiffness, which was not proportional to the apparent axial stiffness of the fibre. If the apparent axial stiffness is a measure of the fraction of cross-bridges bound to actin, it follows that the radial elastic constant is state dependent; or vice versa.8. Differences in equilibrium lattice spacing and in radial elastic constant, most probably reflect differences in the molecular structure of the acto-myosin complex and there is more than one single conformation of the various strongly bound cross-bridge states.9. Determining equilibrium spacings of the radial elasticity appears to be an effective new approach in detecting structural differences among the attached cross-bridges, since this approach is independent of the fraction of cross-bridges attached, a factor that frequently encumbers the interpretation of structural studies of attached cross-bridge states.

The effects of force inhibition by sodium vanadate on cross-bridge binding, force redevelopment, and Ca2+ activation in cardiac muscle

Strongly bound, force-generating myosin cross-bridges play an important role as allosteric activators of cardiac thin filaments. Sodium vanadate (Vi) is a phosphate analog that inhibits force by preventing cross-bridge transition into force-producing states. This study characterizes the mechanical state of cross-bridges with bound Vi as a tool to examine the contribution of cross-bridges to cardiac contractile activation. The K(i) of force inhibition by Vi was approximately 40 microM. Sinusoidal stiffness was inhibited with Vi, although to a lesser extent than force. We used chord stiffness measurements to monitor Vi-induced changes in cross-bridge attachment/detachment kinetics at saturating [Ca(2+)]. Vi decreased chord stiffness at the fastest rates of stretch, whereas at slow rates chord stiffness actually increased. This suggests a shift in cross-bridge population toward low force states with very slow attachment/detachment kinetics. Low angle x-ray diffraction measurements indicate that with Vi cross-bridge mass shifted away from thin filaments, implying decreased cross-bridge/thin filament interaction. The combined x-ray and mechanical data suggest at least two cross-bridge populations with Vi; one characteristic of normal cycling cross-bridges, and a population of weak-binding cross-bridges with bound Vi and slow attachment/detachment kinetics. The Ca(2+) sensitivity of force (pCa(50)) and force redevelopment kinetics (k(TR)) were measured to study the effects of Vi on contractile activation. When maximal force was inhibited by 40% with Vi pCa(50) decreased, but greater force inhibition at higher [Vi] did not further alter pCa(50). In contrast, the Ca(2+) sensitivity of k(TR) was unaffected by Vi. Interestingly, when force was inhibited by Vi k(TR) increased at submaximal levels of Ca(2+)-activated force. Additionally, k(TR) is faster at saturating Ca(2+) at [Vi] that inhibit force by > approximately 70%. The effects of Vi on k(TR) imply that k(TR) is determined not only by the intrinsic properties of the cross-bridge cycle, but also by cross-bridge contribution to thin filament activation.

Manipulation of energy and redox states in the C6 glioma cells by buthionine sulfoxamine and N-acetylcysteine and the effect on cell survival to cadmium toxicity

Changes in cellular energy and redox states were studied in the C6 glioma cells following exposure to chemicals that affect glutathione metabolism. It was demonstrated that treatment with sublethal concentrations (25, 50 and 100 microM) of buthionine sulfoxamine (BSO) did not affect cellular energy state as measured by total adenosine nucleotides (TAN=ATP+ADP+ AMP), ATP:ADP:AMP and energy charge potential (ECP=[ATP + 0.5 (ADP)]/TAN). However, there was a significantly decrease in cellular GSH/GSSG and total glutathione (TG=[GSH+GSSG]/ TAN). The change was due to a significant decrease in intracellular GSH level without significant change in [GSSG]. Cells exposed to BSO for 24 hr were much more sensitive to subsequent injuries caused by Cd (0.6 mM for 3 hr). The results indicated that while a significant reduction of intracellular redox state did not affect cell viability, it could increase the susceptibility of cells to subsequent chemical stress. N-acetylcysteine (NAC), on the other hand, caused a dose (1, 5 and 10 mM)-dependent increase in GSH/GSSG without significant changes in intracellular energy state. Improvement of intracellular GSH/GSSG offered no protection against subsequent Cd induced cell death unless NAC was present at the time Cd was added. The pattern of cell death also correlated with the increase in intracellular free radial generation as measured by the fluorescence labeling with 27- dichlorofluorescin. Results of the present study demonstrated that intracellular redox states could be manipulated by addition of chemicals that affect glutathione metabolism. While the redox state may not be the sufficient condition to cause cell death, it could modulate the response of cells to subsequent Cd treatment. Furthermore, the action of NAC against Cd cytotoxicity may not be related to intracellular redox status.

Glutathione peroxidase and glutathione reductase activities are partially responsible for determining the susceptibility of cells to oxidative stress

Different cell types response differently to toxic insult. In a previous study, it was demonstrated that the C6 glioma cell is more sensitive to Cd induced oxidative stress than the HepG2 cells. To explain the difference between the two cell lines in their response to oxidative stress, it was hypothesized that the activity of glutathione metabolizing enzymes may be different. The objective of this study is to determine the activities of glutathione peroxidase (GPx) and glutathione reductase (GR) in the two cell lines and to explain how these differences may affect the susceptibility of the two cells to oxidative stress. In the HepG2 cells, the activity of GPx was 2.24+/-0.18 micromol/mg protein/min and that for GR was 5.63+/-0.58 micromol/mg protein/min. For the C6 glioma cells, GPx and GR activities were 1.29+/-0.14 and 1.07+/-0.11 micromol/mg protein/min, respectively. Using the kinetic equilibrium: K(eq)=([GSSG]x[NADPH]x[H(+)])/([GSH](2)x[NADP(+)]), and the GSH/GSSG previously published (HepG2: 2.6 and C6 glioma: 3.6), resting NADPH/NADP(+) for the cell lines were calculated. The results showed that NADPH/NADP(+) for HepG2 cells (17.8) is higher than that in the C6 glioma cells (10.8). These data supported the notion that the reducing power (NADPH/NADP(+)) in the HepG2 cells is higher than that in the C6 glioma cell and thus, the later would be more susceptible to oxidative stress. The results also suggested that besides GSH/GSSG, the activities of GPx and GR are important in predicting tissue redox state. Applying this hypothesis to animal tissues, the ratio of the activities of the two enzymes in mouse liver, cerebral cortex, hippocampus and cerebellum were measured. It was demonstrated that the activities of GPx and GR were different in the different tissues studied. The possible correlation between enzymatic activities and the redox state in the different tissues were discussed.

Pediatric Hodgkin's and non-Hodgkin's lymphomas: a retrospective analysis at the Children's Hospital of New Orleans

Lymphomas constitute 10-12% of childhood cancers and are the third most common childhood malignancy. A retrospective analysis of thirty-six patients from the tumor registry of Children's Hospital of New Orleans was conducted during the period from 1995-2000. Patients were divided based on patient and tumor characteristics with recurrence and survival data compared to the Surveillance, Epidemiology and End Results (SEER) data of the National Cancer Institute. There were 18 patients (51%) with Non-Hodgkin's Lymphoma (NHL) and 17 (49%) with Hodgkin's disease (HD). Our sample had a similar distribution compared to the national population cohort except for different gender distribution in our HD patients. Also, most of our patients (63%) presented with advanced disease (Stages III and IV). Seventeen percent had recurrence of disease and 80% achieved remission, of which two patients developed secondary leukemia. Overall mortality was 17%. The survival in patients with HD was 94% which is comparable if not slightly superior to the national data. In patients with NHL, survival was 72% which was marginally lower than the national results (80%), most likely due to more advanced disease. Increased awareness in the pediatric community of the signs and symptoms of childhood lymphoma should result in earlier diagnosis and improved survival.

A novel reduced-intensity stem cell transplant regimen for nonmalignant disorders

Bone marrow transplantation (BMT) benefits nonmalignant diseases but is limited by regimen-related toxicity, graft-versus-host disease (GVHD), donor availability, and graft rejection (GR). To overcome some of these barriers, we developed a new conditioning strategy for these patients. In total, 16 patients received Campath-1H (33/48 mg; days -21 to -19), fludarabine (150 mg/m(2); days -8 to -4), melphalan (140/70 mg/m(2); day -3), and transplant using related/unrelated stem cells. GVHD prophylaxis included cyclosporine/methylprednisolone for cord cells. Other recipients also received methotrexate. Risk factors for GR included multiple transfusions (6), low stem cell numbers (1), and immunologic/metabolic disorders (3). Donor engraftment was present in 14/16 recipients. Neutrophils (ANC>0.5 x 10(9)/l) and platelets (>50 x 10(9)/l) engrafted at a median of 13 and 24 days. Two patients died of Pseudomonas sepsis prior to engraftment, one of CMV disease, and another of intracranial hemorrhage. With median follow-up of 281 days (78-907), 12/16 are stable/improved, or cured. Acute GVHD was absent (n=10) or mild and transient (grade1-2 skin) (n=4). There was no chronic GVHD. Toxicities were predominantly early infections within 100 days, and correlated with lymphopenia (CD4+ T and B cells). Stable engraftment and low incidence of significant GVHD, irrespective of age or stem cell source, make this reduced-intensity regimen attractive for nonmalignant disorders.

Analysis of changes in energy and redox states in HepG2 hepatoma and C6 glioma cells upon exposure to cadmium

The energy and redox states of the HepG2 hepatoma and the C6 glioma cells were studied by quantifying the levels of ATP, ADP, AMP, GSH, and GSSG. These values were used to calculate the energy charge potential (ECP = [ATP + 0.5ADP]/TAN), total adenosine nucleotides (TAN = ATP + ADP + AMP), total glutathione (TG = [GSH + GSSG]/TAN), and the redox state (GSH/GSSG ratio). For comparison between cell types, the level of each energy metabolite (ATP, ADP, and AMP) was normalized against TAN of the respective cell. The results showed that ATP:ADP:AMP ratio was 0.76:0.11:0.13 for the HepG2 cells and 0.80:0.11:0.09 for the C6 glioma cells. ECP was 0.81 +/- 0.01 and 0.85 +/- 0.01 for the HepG2 and the C6 glioma cells, respectively. GSH/GSSG ratio was 2.66 +/- 0.16 and 3.63 +/- 0.48 for HepG2 and C6 glioma cells, respectively. TG was 3.2 +/- 0.54 for the HepG2 cells and 2.43 +/- 0.18 for the C6 glioma cells, indicating that the level of total glutathione is more than two to three times higher than the total energy metabolites in these cell lines. Following a 3-h incubation in medium containing different concentrations of Cd, there was a dose-dependent decrease in cell viability. The 3-h LC50 for the HepG2 cells was 0.5 mM and that for the C6 glioma cells was 0.4 mM. Cellular TAN decreased with a decrease in cell viability. Upon careful analysis of the energy state, there was a significant increase in relative amount of ATP and decrease in ADP and AMP in both cells as Cd concentration increased from 0 to 0.1, 0.2, and 0.6 mM. However, ECP in both cell lines increased, which indicated that the level of high energy phosphate was adequate. There was also a significant increase in TG and a significant decrease in GSH/GSSG in the C6 glioma cells when cells were exposed to as low as 0.1 mM Cd, which suggested that the cellular redox state was compromised. The HepG2 cells, on the other hand, showed no significant change in both TG and GSH/GSSG level until Cd concentration reached 0.6 mM. Results of the present study also showed that there were differences between the two cells in response to the same level of Cd exposure. The C6 glioma cells were more sensitive to Cd-induced injuries. Although there was a decrease in total amount of high energy phosphate as cell viability decreased, the surviving cells were not devoid of high energy phosphates. The relative abundance of ATP amongst the adenosine nucleotide pool and the increase in ECP could be interpreted as a way the cells signal the conservation of energy utilization in response to the damaged mitochondrial function. This move for energy conservation might be the cause of eventual cell death through the process of apoptosis.

Diagnosis and characterization of Hb C/Hb Iowa: a rare but easily misidentified compound heterozygous condition

Hb Iowa is a rare hemoglobin (Hb) variant with a Gly --> Ala substitution at position 119 of beta-globin. It was previously reported only in an African American infant who was also heterozygous for Hb S [beta6(A3)Glu --> Val] and her mother (Hb A/Iowa). Here we describe the second report of Hb Iowa, the first in conjunction with Hb C [beta6(A3)Glu --> Lys]. The patient was an African American girl, originally diagnosed as homozygous Hb C during neonatal screening. When seen in our clinic, hematological data for both the child and her mother (Hb C trait) indicated mild anemia with slightly low mean corpuscular volume (MCV) but normal red blood cell (RBC) count. Analysis of blood from the child by capillary isoelectric focusing (cIEF) identified Hb C and an unknown Hb variant with an isoelectric point (pI) intermediate to that of Hbs F and A. The unknown variant was identified as Hb Iowa by DNA sequence analysis of the beta-globin gene (GGC --> GCC). Both reported cases of Hb Iowa indicated that there are no abnormal hematological manifestations associated with this rare Hb variant. In both cases, however, Hb Iowa was mistaken for Hb F during routine neonatal screening by high performance liquid chromatography (HPLC) and/or gel IEF. Neonatal misidentification of Hb Iowa led to misdiagnosis of sickle cell disease and Hb C disease, respectively. In our patient, Hb Iowa was also misidentified as Hb A at 2 years of age by a commercial reference laboratory using cellulose acetate and citrate agar gel electrophoresis. This led to an incorrect diagnosis of Hb C trait. These results show that commonly used analytical methods can easily misidentify Hb Iowa as Hbs F or A in neonates, or older individuals, resulting in incorrect identification of the Hb phenotype. We conclude that the presence of Hb Iowa, or other variants with similar pIs, should be considered in cases where the results of follow-up testing conflict with neonatal diagnosis of sickle cell or Hb C disease, or where clinical presentation does not agree with diagnosis of either homozygous or heterozygous Hb S or Hb C.

Autologous Hematopoietic Stem-Cell Transplantation for Children With Acute Myeloid Leukemia in First or Second Complete Remission: A Prognostic Factor Analysis

Purpose

To determine prognostic factors correlated with outcomes after autologous hematopoietic stem-cell transplantation (HSCT) in children with acute myeloid leukemia (AML).

Patients and Methods

We studied 219 children who received autologous HSCT for AML in first complete remission (CR) and 73 children in second CR and who were reported to the Autologous Blood and Marrow Transplant Registry. Among 29 of 73 patients who underwent transplantation in second CR, duration of first CR was ≥ 12 months.

Results

Three-year cumulative incidences of relapse were 37% (95% CI, 31% to 44%), 60% (95% CI, 41% to 74%), and 36% (95% CI, 20% to 53%) for children in first CR, second CR after a short (< 12 months) first CR, and second CR after a long (≥ 12 months) first CR, respectively. Corresponding 3-year probabilities of leukemia-free survival were 54% (95% CI, 47% to 60%), 23% (95% CI, 10% to 39%), and 60% (95% CI, 42% to 75%). In multivariate analyses, risks of relapse, mortality, and treatment failure (relapse or death, inverse of leukemia-free survival) were higher for patients in second CR after a short first CR than for the other two groups. Transplant-related mortality, treatment failure, and overall mortality rates were higher in older (> 10 years) children.

Conclusion

Duration of first CR seems to be the most important determinant of outcome. Results in children who experience treatment failure with conventional chemotherapy support the use of autologous transplantation as salvage therapy if such patients achieve a subsequent CR.

Cultural correlates of self perceived health status among Chinese elderly

This study examines self-perceived physical and mental health among 213 Chinese elderly who visited the Geriatric Outpatient Clinic of Beijing Hospital, the People's Republic of China. The study hypothesizes that cultural factors, specified by family relations, along with demographic factors, number of diseases, economic well-being, and living conditions have a significant impact on subjects self-perceived health status. Pearson correlation, linear and logistic regression analyses are performed. Results indicate that age, number of diseases, perceived family respect, neighborhood relations, and percentage of income spent on rent are significant predictors of self-perceived physical health. These same factors plus preference to live with a son and personal monthly income are significant predictors of self-perceived mental health. Socio-cultural implications of these findings are examined.

Life satisfaction among Chinese elderly in Beijing

The present study examined correlates of life satisfaction among 350 Chinese elderly aged 65 or older. Subjects consisted of a clinic sample (n = 200) and a randomly selected community sample (n = 150) recruited from the same area in Beijing. Linear regression analysis was performed, using health, financial status, and family support as independent variables. Results showed that the regression model explained 38 percent of the variance in life satisfaction in the total sample, 34 percent and 43 percent of the variance respectively in the clinical and community samples. Life satisfaction was significantly predicted by health and financial status among community elderly and by health, financial status, as well as family support among outpatient elderly. Findings suggest that the socio-cultural context has exerted important impacts on the Chinese elderly's life satisfaction.

Temperature and ligand dependence of conformation and helical order in myosin filaments

Mammalian myosin filaments are helically ordered only at higher temperatures (>20 degrees C) and become progressively more disordered as the temperature is decreased. It had previously been suggested that this was a consequence of the dependence of the hydrolytic step of myosin ATPase on temperature and the requirement that hydrolysis products (e.g., ADP.P(i)) be bound at the active site. An alternative hypothesis is that temperature directly affects the conformation of the myosin heads and that they need to be in a particular conformation for helical order in the filament. To discriminate between these two hypotheses, we have studied the effect of temperature on the helical order of myosin heads in rabbit psoas muscle in the presence of nonhydrolyzable ligands. The muscle fibers were overstretched to nonoverlap such that myosin affinity for nucleotides was not influenced by the interaction of myosin with the thin filament. We show that with bound ADP.vanadate, which mimics the transition state between ATP and hydrolysis products, or with the ATP analogues AMP-PNP or ADP.BeF(x)() the myosin filaments are substantially ordered at higher temperatures but are reversibly disordered by cooling. These results reinforce recent studies in solution showing that temperature as well as ligand influence the equilibrium between multiple myosin conformations [Málnási-Csizmadia, A., Pearson, D. S., Kovács, M., Woolley, R. J., Geeves, M. A., and Bagshaw, C. R. (2001) Biochemistry 40, 12727-12737; Málnási-Csizmadia, A., Woolley, R. J., and Bagshaw, C. R. (2000) Biochemistry 39, 16135-16146; Urbanke, C., and Wray, J. (2001) Biochem. J. 358, 165-173] and indicate that helical order requires the myosin heads to be in the closed conformation. Our results suggest that most of the heads in the closed conformation are ordered, and that order is not produced in a separate step. Hence, helical order can be used as a signature of the closed conformation in relaxed muscle. Analysis of the dependence on temperature of helical order and myosin conformation shows that in the presence of these analogues one ordered (closed) conformation and two disordered conformations with distinct thermodynamic properties coexist. Low temperatures favor one disordered conformation, while high temperatures favor the ordered (closed) conformation together with a second disordered conformation.

Unrelated allogeneic bone marrow transplant in adrenoleukodystrophy using CD34+ stem cell selection

Adrenoleukodystrophy is an inherited disease characterized by progressive neurodegeneration with rapid deterioration to a vegetative state. Of the treatment modalities tried to date, BMT is the only one with the potential for cure. However, the high rate of morbidity and mortality associated with allogeneic transplant makes it necessary to try out novel measures to improve the outcome in these patients. We report here a case where we used CD34+ stem cell selection for allogeneic unrelated-donor BMT in a patient with adrenoleukodystrophy.

Structural characterization of weakly attached cross-bridges in the A*M*ATP state in permeabilized rabbit psoas muscle

It is well established that in a skeletal muscle under relaxing conditions, cross-bridges exist in a mixture of four weak binding states in equilibrium (A*M*ATP, A*M*ADP*P(i), M*ATP, and M*ADP*P(i)). It has been shown that these four weak binding states are in the pathway to force generation. In the past their structural, biochemical, and mechanical properties have been characterized as a group. However, it was shown that the myosin heads in the M*ATP state exhibited a disordered distribution along the thick filament, while in the M*ADP*P(i) state they were well ordered. It follows that the structures of the weakly attached states of A*M*ATP and A*M*ADP*P(i) could well be different. Individual structures of the two attached states could not be assigned because protocol for isolating the two states has not been available until recently. In the present study, muscle fibers are reacted with N-phenylmaleimide such that ATP hydrolysis is inhibited, i.e., the cross-bridge population under relaxing conditions is distributed only between the two states of M*ATP and A*M*ATP. Two-dimensional x-ray diffraction was applied to determine the structural characteristics of the attached A*M*ATP state. Because the detached state of M*ATP is disordered and does not contribute to layer line intensities, changes as a result of increasing attachment in the A*M*ATP state are attributable to that state alone. The equilibrium toward the attached state was achieved by lowering the ionic strength. The results show that upon attachment, both the myosin and the first actin associated layer lines increased intensities, while the sixth actin layer line was not significantly affected. However, the intensities remain weak despite substantial attachment. The results, together with modeling (see J. Gu, S. Xu and L. C. Yu, 2002, Biophys. J. 82:2123-2133), suggest that there is a wide range of orientation of the attached A*M*ATP cross-bridges while the myosin heads maintain some degree of helical distribution on the thick filament, suggesting a high degree of flexibility in the actomyosin complex. Furthermore, the lack of sensitivity of the sixth actin layer line suggests that the binding site on actin differs from the putative site for rigor binding. The significance of the flexibility in the A*M*ATP complex in the process of force generation is discussed.

Molecular basis of the adult i phenotype and the gene responsible for the expression of the human blood group I antigen

The human blood group i and I antigens are characterized as linear and branched repeats of N-acetyllactosamine, respectively. Conversion of the i to the I structure requires the activity of I-branching beta-1,6-N-acetylglucosaminyltransferase (IGnT). Thus the blood group I gene is assigned to encode a beta-1,6-N-acetylglucosaminyltransferase; however, its identity has not been confirmed. The null phenotype of I, the adult i phenotype, provides a means to identify the I gene. Interestingly, the adult i phenotype has been noted to be associated with congenital cataracts in Asians. Molecular genetic studies of 3 adult i pedigrees are reported here. The results obtained on mutation detection within the 2 I-branching enzyme encoding genes, segregation analyses, and enzyme function assays identify molecular changes associated with the adult i phenotype. The adult i phenotype in 2 of the pedigrees studied resulted from 1043G-->A and 1148G-->A mutations, which predict Gly348Glu and Arg383His alterations, respectively, in the IGnT gene. These amino acid changes abolished the original GlcNAc-transferase activity. Deletion of the IGnT gene was observed in the person with adult i phenotype in the third pedigree. These findings suggest that the IGnT gene, first reported in 1993, is the candidate for the blood group I gene. Confirmation of the blood group I gene will further assist in the investigations of the molecular genetics that control I antigen expression in secretions and the molecular basis for the association of the adult i phenotype with congenital cataracts in Asians.

Nociceptin/orphanin FQ into the rat periaqueductal gray decreases the withdrawal latency to heat and loading, an effect reversed by (Nphe(1))nociceptin(1-13)NH(2)

The present study investigated the effect of intraperiaqueductal grey injection of nociceptin/orphanin FQ (N/OFQ) and an antagonist (Nphe(1))nociceptin(1-13)NH(2) on the hindpaw withdrawal response to thermal and mechanical stimulation in rats. N/OFQ (5 nmol) significantly decreased the nociceptive thresholds in both tests and 1, 5 and 10 nmol of (Nphe(1))nociceptin(1-13)NH(2) significantly reversed this effect in a dose dependent way. Our results demonstrate, that N/OFQ has a nociceptive action, possibly through inhibition of PAG neurons. This effect is blocked by the antagonist (Nphe(1))nociceptin(1-13)NH(2) probably via ORL1 receptors in the periaqueductal grey.