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L Diller

Publications and source records attributed to L Diller.

At least 37 records · Page 2Linked to original sources
PubMed1996

Pediatric large volume peripheral blood progenitor cell collections from patients under 25 kg: a primer.

Collection of peripheral blood progenitor cells from small pediatric patients provides many social and technical challenges not faced when collecting from adult patients. This paper provides a single institutions experience with 85 collections from 14 patients less than 25 kg of weight over a 2 year period. Specific challenges include obtaining venous access, anticoagulation, volume shifts, and obtaining patient cooperation. A systematic analysis of options for access, alternative modes of anticoagulation, and the effect of large ratios of extra-corporeal volume to patient's blood volume are discussed. Access uniformly required central venous catheters (CVC) ranging from 7-10 Fr. Anticoagulation included systemic heparinization titrating dose by activated clotting time in all cases and combined with citrate at a ratio of 1:25-1:30 in most cases. Collections were performed on a COBE Spectra, after priming with leukoreduced irradiated red cells and omitting both the initial 120cc diversion and rinse back of red cells at the end. Social challenges include issues of assent and ability to distract patients for the duration of a prolonged collection. Progenitor yields from collections from 14 patients were quantitated by CD34+ assay in all cases and CFU-GM in ten of 14 patients. A median of 4.5 x 10(6)/kg CD34+ cells were obtained for each collection. Complications, including those related to catheter access, are enumerated. In summary, large volume peripheral blood progenitor collection can be safely and efficaciously performed in small pediatric patients.

Body Weight↗
PubMed1996

Pneumococcal conjugate vaccine primes for antibody responses to polysaccharide pneumococcal vaccine after treatment of Hodgkin's disease.

Thirty-nine previously treated Hodgkin's disease (HD) patients were immunized with 7-valent pneumococcal conjugate vaccine (7-OMPC) followed by one dose of 23-valent polysaccharide pneumococcal vaccine (23-PS). To determine the priming effect of 7-OMPC vaccine, their antibody responses to six serotypes contained in both vaccines were compared to those of 57 HD patients who received 23-PS vaccine only. The geometric mean antibody concentrations after immunization with 23-PS vaccine were significantly higher for five of the six measured serotypes in HD patients primed with 7-OMPC vaccine compared with responses in HD patients who received 23-PS vaccine only. The mean of the six antibody concentrations was significantly higher for the primed group at 12.5 micrograms/mL and 7.76 micrograms/mL, respectively (P = .015). Priming with a conjugate vaccine should be considered as a strategy to protect high-risk adults.

Adolescent↗
PubMed1996

Percutaneous biopsy for prognostic testing of neuroblastoma.

PURPOSE: To determine whether percutaneous biopsy can provide the diagnostic and prognostic information necessary to treat children with advanced neuroblastoma. MATERIALS AND METHODS: From 1991 through 1995, 21 percutaneous biopsies were performed in 20 children with advanced neuroblastoma by using 15- or 16-gauge core biopsy needles. An average of six samples were obtained. Since September 1994, fresh tissue was sent to the reference laboratory, where touch preparations were prepared for N-myc evaluation. RESULTS: Histologic confirmation and prognostic information (Shimada classification) were obtained in all cases. Genetic prognostic information was obtained in 19 patients (95%), DNA index (ploidy) in 18 (90%), N-myc gene expression in 14 (70%), and cytogenetic analysis in 10 (50%). N-myc and ploidy determinations were successful in all five biopsy specimens obtained since September 1994. CONCLUSION: Percutaneous biopsy of advanced neuroblastoma is a feasible alternative to open biopsy.

Adolescent↗
PubMed1995

Antibody responses to polysaccharide and polysaccharide-conjugate vaccines after treatment of Hodgkin disease.

OBJECTIVE: To compare the immunogenicity of polysaccharide-conjugate vaccines with that of polysaccharide vaccines in patients previously treated for Hodgkin disease. DESIGN: All patients were immunized with Haemophilus influenzae type b (HIB)-conjugate and 4-valent meningococcal polysaccharide vaccines. Subgroups of patients were randomly assigned to receive either 23-valent pneumococcal polysaccharide vaccine or a 7-valent pneumococcal-conjugate vaccine that links seven pneumococcal serotypes to the outer membrane protein complex of Neisseria meningitidis. PATIENTS: 144 patients who had completed treatment for Hodgkin disease, which had been diagnosed at least 2 years before the study. MEASUREMENTS: Antigen-specific antibody concentrations before and 3 to 6 weeks after immunization; number of persons who achieved anti-HIB antibody concentrations considered to be in the protective range. RESULTS: The geometric mean anti-HIB antibody concentration increased from 1.79 micrograms/mL before immunization to 54.1 micrograms/mL after; the percentage of persons with antibody concentrations in the protective range increased from 62% before immunization to 99% after. Patients immunized with 23-valent pneumococcal vaccine had a geometric mean pneumococcal antibody concentration after immunization (9.15 micrograms/mL) that was similar to that of healthy controls (10.0 micrograms/mL) for the seven serotypes measured. In contrast, patients who received 7-valent pneumococcal-conjugate vaccine had a significantly lower mean response compared with patients who received 23-valent; their geometric mean antibody concentration after immunization was 4.95 micrograms/mL (P = 0.005). CONCLUSION: A single dose of HIB-conjugate vaccine was immunogenic in patients who had completed treatment for Hodgkin disease diagnosed at least 2 years before immunization. In addition, responses to the 23-valent pneumococcal and 4-valent meningococcal vaccines were equivalent to those seen in healthy controls. Finally, patients had a significantly lower response to a single dose of 7-valent pneumococcal-conjugate vaccine than to 23-valent vaccine.

Bacterial Capsules↗
PubMed1995

Germline p53 mutations are frequently detected in young children with rhabdomyosarcoma.

We investigated the possibility that a proportion of children with sporadic rhabdomyosarcoma (RMS) carry constitutional mutations of the p53 tumor suppressor gene. 33 patients with sporadic RMS at two large outpatient pediatric oncology clinics submitted blood samples. Genomic DNA was extracted from peripheral blood leukocytes and PCR was used to amplify exons 2-11 of the p53 gene. Amplified genomic DNA was screened for the presence of germline p53 mutations using single-strand conformation polymorphism (SSCP) analysis. The DNA sequence of those samples that showed aberrant migration of bands on SSCP analysis was determined to identify the precise nature of the gene mutations. Patient records were reviewed to assess clinical correlates of the mutant p53 carrier state. Heterozygous constitutional mutations were detected in 3/33 patient samples screened. Two of these missense mutations are located in exon 7 and one in exon 8 of the p53 gene. The presence of mutations was not correlated with tumor histology, stage, or site. However, an association between young age at diagnosis and presence of a constitutional p53 mutation was noted: 3/13 children under the age of 3 yr at diagnosis carried mutations, whereas none of 20 children over 3 yr of age at diagnosis harbored a detectable constitutional mutation. These results in children with RMS corroborates previous findings in other clinical settings suggesting that the mutant p53 carrier state may predispose individuals to malignancy at an early age. Although this study did not assess whether the mutations were preexisting or new germline alterations, assessment of close relatives of RMS patients for cancer risk and predictive genetic testing may be indicated.

Adolescent↗
PubMed1994

Preferential amplification of the paternal allele in neuroblastomas with N-myc amplification.

There is increasing evidence that imprinting plays an important role in influencing the parental origin of genes involved in cancer-specific rearrangements. In advanced stage neuroblastomas, both allelic loss of the short arm of chromosome 1 (1p) and amplification of the proto-oncogene N-myc are often seen. Therefore, we analyzed 22 human neuroblastomas with N-myc amplification to determine the parental origin of the N-myc allele that is amplified and the 1p allele that is deleted. We used at least three polymorphisms for both the 1p and the N-myc locus to analyze blood and tumor samples from neuroblastoma patients, as well as blood samples from their parents. We determined that the paternal allele of N-myc was amplified in 12 of 15 informative cases (P = 0.02), and the paternal allele on 1p was lost in 6 of 11 informative cases (P > 0.2). These results suggest that parental imprinting does not appear to affect the 1p allele that is deleted, at least in the cases that we have examined. However, imprinting has an important influence on determining the N-myc allele that is amplified in these tumors, suggesting that the paternal allele is either more highly expressed or more likely to undergo amplification.

Alleles↗
PubMed1993

Preferential amplification of the paternal allele of the N-myc gene in human neuroblastomas.

Genomic imprinting plays a role in influencing the parental origin of genes involved in cancer-specific rearrangements. We have analysed 22 neuroblastomas with N-myc amplification to determine the parental origin of the amplified N-myc allele and the allele that is deleted from chromosome 1p. We analysed DNA from neuroblastoma patients and their parents, using four polymorphisms for 1p and three for the N-myc amplicon. We determined that the paternal allele of N-myc was preferentially amplified (12 out of 13 cases; P = 0.002). However, the paternal allele was lost from 1p in six out of ten cases, consistent with a random distribution (P > 0.2). These results suggest that parental imprinting influences which N-myc allele is amplified in neuroblastomas, but it does not appear to affect the 1p allele that is deleted in the cases that we have examined.

Adrenal Gland Neoplasms↗
PubMed1993

Screening children at genetic risk of cancer.

The explosion in molecular technology has brought with it a new era in medical genetics. In the past, genes easiest to work with were those responsible for heritable disorders manifesting in childhood that were often the consequence of metabolic derangements. The disorders were detectable either at birth or soon after either because of physical appearance or the development of a clinical problem. It is now possible to identify genes that confer increased susceptibility to diseases that may not be manifest until late adulthood; such as cancer or heart disease. This review discusses conditions in which children may now be identified as genetically at increased risk for cancer development in childhood or adulthood, and current dilemmas regarding appropriate screening strategies for these at-risk individuals.

Child↗
PubMed1993

Prenatal detection of neuroblastoma: a ten-year experience from the Dana-Farber Cancer Institute and Children's Hospital.

OBJECTIVES: To assess the relative frequency of, the clinical and pathological correlates in, and the prognosis of the subset of infants with neuroblastoma who were identified initially by prenatal ultrasonography. DESIGN: Retrospective review of all patients with neuroblastoma evaluated between 1982 and 1992. SETTING: Large, urban, tertiary care children's hospital in Boston, Massachusetts. PATIENTS: Eleven infants with neuroblastoma initially detected with prenatal sonograms were identified. RESULTS: Nine patients had adrenal tumors; two had thoracic paraspinal tumors. Typical diagnostic evidence for neuroblastoma including a palpable abdominal mass and elevations in urinary catecholamines were not commonly seen postnatally. These patients had multiple favorable prognostic indicators including low stage of disease (10/11), favorable biological markers including cellular DNA content (5/5) and N-myc oncogene copy number (5/5), and histopathology suggestive for neuroblastoma in situ (7/11). All patients were treated by surgical resection. One patient exhibited progression of disease postoperatively, but demonstrated a complete clinical response to multiagent chemotherapy. Overall survival in our population was excellent with no deaths seen at a mean follow-up of 37 months (range 3 to 120 months). CONCLUSIONS: Patients with neuroblastoma identified by prenatal ultrasonography generally, although not exclusively, follow a clinically favorable course in which surgical resection is curative. Chemotherapy is not indicated unless substantial progression of disease occurs.

Adrenal Gland Neoplasms↗
PubMed1993

Cognitive remediation in traumatic brain injury: update and issues.

Cognitive Remediation (CR) is a relatively new treatment technique for alleviating residual cognitive deficits following traumatic brain injury. This is a promising yet still changing technique. The future of CR as a rational and systematic endeavor requires the incorporation of important new ideas that have been emerging in allied fields. For example, the emerging field of instructional psychology has contributed relevant concepts such as scaffolding, metacognition, and generalization. It is furthermore argued that the issues of awareness, self-concept, and self-efficacy are vital to the process of CR intervention, and an integrative (holistic) approach to the remedial endeavor is thus indicated.

Activities of Daily Living↗
PubMed1992

Structure and expression of the Xenopus retinoblastoma gene.

We have cloned a Xenopus homology (XRb1) of the human retinoblastoma susceptibility gene. DNA sequence analysis shows that the XRb1 gene product is highly conserved in many regions. The leucine repeat motif and many of the potential cdc2 phosphorylation sites, as well as potential sites for other kinases, are retained. The region of the protein homologous to the SV40 T antigen binding site and the basic region directly C-terminal to the E1A binding site are all conserved. XRb1 gene expression at the RNA level was studied by Northern blot analysis. Transcripts of 4.2 and 10-kb are present as maternal RNA stores in the oocyte. While the 4.2-kb product is stable until at least the mid-blastula stage, the 10-kb transcript is selectively degraded. Between stages 11 and 13 the 10-kb transcript reappears and also a minor product of approximately 11 kb becomes apparent. Both the 4.2- and the 10-kb transcripts remain present until later stages of development and are also present in all adult tissues examined, although at differing levels. Antibodies raised against human p105Rb which recognize the protein product of the XRb1 gene, pXRb1, detect the Xenopus 99-kDa protein prior to the mid-blastula stage, but at lower levels than at later stages in development.

Amino Acid Sequence↗
PubMed1992

Stress, appraisal, and coping in mothers of disabled and nondisabled children.

The cognitive-behavioral model of stress and coping provided the framework for this study of mothers of physically disabled children (n = 69) and mothers of nondisabled children (n = 63). The first aim was to test for differences between groups in responses to stressful parenting events. As hypothesized, mothers of disabled children reported higher levels of depressive symptomatology. Differences in psychological distress and health status approached significance. The second aim was to explore the mediating influences of coping strategies and cognitive appraisals. As predicted, emotion-focused coping was related to increased psychological distress in mothers of disabled children whereas problem-focused coping was associated with decreased distress. Both relationships were significant even after controlling for differences in type of parenting stressor. Hierarchical regressions showed that 58 and 25% of the variance in psychological distress was explained by the independent variables; however, the predictors were different for the two groups of mothers. Factors that may explain the differential effectiveness of coping and appraisal, and clinical implications of this study are discussed.

Adaptation, Psychological↗
PubMed1992

Rhabdomyosarcoma and other soft tissue sarcomas of childhood.

Childhood rhabdomyosarcoma and the other soft tissue sarcomas of childhood are a heterogeneous group of tumors with many histologic subtypes, affecting multiple anatomic locations and requiring the care of subspecialists from a variety of disciplines. Epidemiologic studies of childhood sarcomas indicate that a familial predisposition to malignancy may contribute to tumorigenesis in a proportion of patients. Diagnosis of these tumors may be difficult; immunohistochemical and cytogenetic analysis is clearly important. Large cooperative group studies have answered important treatment questions in past years; these studies are now being analyzed for clues to effective treatment of specific histologic and anatomic subgroups. The Intergroup Rhabdomyosarcoma Study IV is now open and the questions addressed are reviewed. New developments in late effects of therapy for childhood sarcoma are considered.

Adult↗
PubMed1992

Identification of cancer-prone individuals: p53 and family cancer syndromes.

Progress in prevention of any disease is enhanced by the identification of a group of individuals who are at increased risk to develop the disease. The ability to detect families with evident predisposition to malignancy provides a unique opportunity to study high-risk groups. Recent studies of the p53 gene have suggested that heritable mutations in this gene may predispose affected individuals to the development of a wide variety of tumors. In this article, evidence for the involvement of p53 in inheritable cancers is assessed, and the implications for future studies are discussed.

Genes, p53↗
PubMed1990

p53 functions as a cell cycle control protein in osteosarcomas.

Mutations in the p53 gene have been associated with a wide range of human tumors, including osteosarcomas. Although it has been shown that wild-type p53 can block the ability of E1a and ras to cotransform primary rodent cells, it is poorly understood why inactivation of the p53 gene is important for tumor formation. We show that overexpression of the gene encoding wild-type p53 blocks the growth of osteosarcoma cells. The growth arrest was determined to be due to an inability of the transfected cells to progress into S phase. This suggests that the role of the p53 gene as an antioncogene may be in controlling the cell cycle in a fashion analogous to the check-point control genes in Saccharomyces cerevisiae.

Amino Acid Sequence↗
PubMed1989

A preliminary comparison of flat affect schizophrenics and brain-damaged patients on measures of affective processing.

Flat affect is a major component of schizophrenia and is often also seen in neurological disorders. A preliminary set of comparisons were conducted to delineate neuropsychological mechanisms underlying flat affect in schizophrenia, and new measures are described for the assessment of affective deficits in clinical populations. Subjects were schizophrenic with flat affect (SZs), right brain-damaged (RBD), Parkinson's Disease (PDs), and normal control (NC) right-handed adults. Subjects were administered affective measures of expression and perception in both facial and vocal channels. For both perceptual and expressive tasks the SZs performed significantly less accurately than the NCs and the PDs but did not differ from the RBDs. This was the case for both face and voice. This finding lends support to the speculation that right hemisphere mechanisms, especially cortical ones, may be compromised among schizophrenics with flat affect.

Adult↗