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C Carrier

Publications and source records attributed to C Carrier.

At least 19 recordsLinked to original sources
PubMed2000

Mitochondrial GPx1 decreases induced but not basal oxidative damage to mtDNA in T47D cells.

The production of oxyradicals by mitochondria (mt) is a source of oxidative damage to mtDNA such as 8-oxo-dG lesions that may lead to mutations and mitochondrial dysfunction. The potential protection of mtDNA by glutathione peroxidase-1 (GPx1) was investigated in GPx1-proficient (GPx-2) and GPx1-deficient (Hygro-3) human breast T47D cell transfectants. GPx activity and GPx1-like antigen concentration in mitochondria were respectively at least 100-fold and 20- to 25-fold higher in GPx2 than Hygro-3 cells. In spite of this large difference in peroxide-scavenging capacity, the basal 8-oxo-dG frequency in mtDNA, assessed by carefully controlled postlabeling assay, was strikingly similar in both cell lines. In contrast, in response to menadione-mediated oxidative stress, induction of 8-oxo-dG and DNA strand breaks was much lower in the GPx1-proficient mitochondria (e.g., +14% 8-oxo-dG versus +54% in Hygro-3 after 1-h exposure to 25 microM menadione, P < 0.05). Our data indicate that the mitochondrial glutathione/GPx1 system protected mtDNA against damage induced by oxidative stress, but did not prevent basal oxidative damage to mtDNA, which, surprisingly, appeared independent of GPx1 status in the T47D model.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed2000

Measurements from normal umbilical cord blood of four lysosomal enzymatic activities: alpha-L-iduronidase (Hurler), galactocerebrosidase (globoid cell leukodystrophy), arylsulfatase A (metachromatic leukodystrophy), arylsulfatase B (Maroteaux-Lamy).

Umbilical cord blood (UCB) has received increasing attention as a source of unrelated hematopoietic stem cells for transplantation. Lysosomal diseases have been effectively treated and normal enzymatic activity has occurred subsequent to engraftment using UCB. The use of donor cells with normal amounts of enzyme, rather than those from carriers whose level may be 50% or less, is an obvious goal. The frequency of such heterozygotes varies from 1:10 to 1:140 or lower depending upon the disease at issue. We assayed the levels of lysosomal enzymes in normal UCB in random samples as well as those used for transplantation. We measured the following enzymatic activities: alpha-l-iduronidase (Hurler), galactocerebrosidase (globoid cell leuko- dystrophy) and arylsulfatase A (metachromatic leukodystrophy). For the latter, levels of activity in UCB are comparable to those found in adult blood. In the case of arylsulfatase B (Maroteaux-Lamy) a level lower than adult level was found. An informed choice by the transplanting physician based on the activity of the relevant enzyme in the UCB donor will provide a better opportunity for an improved prognosis for more complete correction of the recipient's primary disease. Bone Marrow Transplantation (2000) 25, 541-544.

Adult↗
PubMed2000

[Physical and sports activities in the history of patients treated for addictions. Report 1999 of the study sponsored by the Ministry of Youth and Sports (France)].

Early February 1999, the French Ministère de la Jeunesse et des Sports (Youth and Sports Ministry) sponsored three different studies, aiming to prevent harmful behavior in the area of sport practices among youth. Two years earlier, our health care team working with drug users published reports on the meaningfulness of intensive sports activities in the history of our patients. The present work was performed to highlight the midterm results of one of these studies, to better understand and quantify the importance of physical training in the history of a group of outpatients seen for addictive disorders and comorbid pathologies. For 20 consecutive weeks, 3,040 self-administered questionnaires were available for persons consulting 20 health centers, 2 self-help groups and a general practitioner network working in the field of alcohol or heroine abuse. One thousand one hundred and eleven questionnaires were filled out (36.1%) and returned by mail for complete analysis: 86% of the answering persons had practiced at least one sports activity or participated in physical training, 10.5% had participated in a national or international level competition, and 10.6% reported stress fractures. In the intensive sports group, 36% had used illicit drugs intravenously and 16.4% said they had already used doping substances. Only 28.4% said they experienced dependence during their period of intensive sports activities compared with 15.2% before this time, and a majority (56.4%) thereafter. Intensive sports or physical training should not be seen as a protective factor nor as a way of improving addictive behaviors. More studies are needed to evaluate individual vulnerability factors and specific harm of overtraining and to determine the exact periods when men and women participating in sports activities are likely to abuse drugs, especially at the end of their career.

Adult↗
PubMed2000

[Strive for excellence and addiction to body movement: a risk model in high-level athletes].

Champion athletes strive to attain a personal goal defined by a socially constructed image of psychomotor performance to be accomplished at the moment of the championship celebration. This intrapsychic process is initiated by a transformation of the body, programmed and controlled by repeated training. The athlete's body becomes accustomed to ritualized obsessive movements, favoring the feeling of self-fulfillment solely during muscular effort (contraction/relaxation, displacement). This social goal of excellence implies personal adaptation involving an addictive link to movement: a mechanism uniquely valid in high level sports. Twelve years experience in psychological support of high-level athletes participating in Olympic sports has led to an analysis of this adaptive mechanism and a proposed psychopathological model of its invasion of the athlete's psychic economy.

Behavior, Addictive↗
PubMed1998

Outcomes among 562 recipients of placental-blood transplants from unrelated donors.

BACKGROUND: A program for banking, characterizing, and distributing placental blood, also called umbilical-cord blood, for transplantation provided grafts for 562 patients between August 24, 1992, and January 30, 1998. We evaluated this experience. METHODS: Placental blood was stored under liquid nitrogen and selected for specific patients on the basis of HLA type and leukocyte content. Patients were prepared for the transplantation of allogeneic hematopoietic cells in the placental blood and received prophylaxis against graft-versus-host disease (GVHD) according to routine procedures at each center. RESULTS: Outcomes at 100 days after transplantation were known for all 562 patients, and outcomes at 1 year for 94 percent of eligible recipients. The cumulative rates of engraftment among the recipients, according to actuarial analysis, were 81 percent by day 42 for neutrophils (median time to engraftment, 28 days) and 85 percent by day 180 for platelets (median, day 90). The speed of myeloid engraftment was associated primarily with the leukocyte content of the graft, whereas transplantation-related events were associated with the patient's underlying disease and age, the number of leukocytes in the graft, the degree of HLA disparity, and the transplantation center. After engraftment, age, HLA disparity, and center were the primary predictors of outcome. Severe acute GVHD (grade III or IV) occurred in 23 percent of patients, and chronic GVHD occurred in 25 percent. The rate of relapse among recipients with leukemia was 9 percent within the first 100 days, 17 percent within 6 months, and 26 percent by 1 year. These rates were associated with the severity of GVHD, type of leukemia, and stage of the disease. CONCLUSIONS: Placental blood is a useful source of allogeneic hematopoietic stem cells for bone marrow reconstitution.

Actuarial Analysis↗
PubMed1996

Detection of maternal DNA in placental/umbilical cord blood by locus-specific amplification of the noninherited maternal HLA gene.

A critical issue regarding the broader utilization of placental/ umbilical cord blood (PCB) in unrelated bone marrow restoration is the possibility of contamination with maternal lymphocytes capable of immunological reactivity against the eventual recipient. On transplantation, such maternal cells might lead to graft-versus-host disease (GVHD) even if the intended donor's neonatal lymphocytes were unresponsive. We measured the proportion of PCB samples that were contaminated with maternal cells. Placental-maternal sample pairs were selected so that the mother was heterozygous for the DR53 haplotype, whereas the placental sample was DR53-negative. The PCB samples were investigated for the presence of the noninherited maternal gene DRB4, exclusive to the DR53 haplotypes. Locus-specific polymerase chain reaction amplification with DRB4 sequence-specific primers was followed by either gel electrophoresis or blotting and hybridization to an internal sequence DRB4 probe. Polymerase chain reaction products from DNA mixtures containing as low as 0.5 ng of a DRB4-positive DNA control in 1.0 microgram of a DRB4-negative DNA sample (1:2 x 10(3) dilution) showed a visible DRB4 band in agarose gels stained with ethidium bromide. Locus-specific hybridization increased the detection sensitivity to 1:10(5) (0.01 ng of the DRB4-positive DNA control). Control mixtures of known amounts of DRB4-positive and -negative DNA were included in all experiments. Comparison of the thickness of DRB4 bands after electrophoresis and the intensity of the DRB4-specific hybridization signals to the concentration controls allowed a rough estimation of the amount of maternal DNA in the placental blood specimens. A total of 213 PCB samples were tested. By gel electrophoresis, DRB4-specific bands were observed to be as strong or stronger in 23 (10.8%) samples as those in the 1:2 x 10(3) control, and 153 (17.8%) samples were negative in this test. The remaining 37 (17.3%) samples disclosed weaker DRB4 bands, suggesting the presence of maternal genetic material. By hybridization, 81 (38%) samples were positive and 132 were negative for the noninherited maternal gene. Review of the clinical characteristics of the mothers (demographics and labor and delivery information), the newborns (birth weight, sex, and gestational age), and PCB collections (placental weight, white blood cell count, and collected volume) failed to show any significant differences between the units testing positive or negative for the noninherited maternal gene. Thus, transplantable PCB units carry a high probability of having maternal DNA in detectable amounts. Whether this DNA comes from potentially graft-versus-host disease-inducing maternal lymphocytes or whether the putatively transplacentally-acquired maternal cells are immunologically dysfunctional, as in most infants with severe combined immunodeficiency disease, remains to be shown.

Alleles↗
PubMed1996

Placental blood as a source of hematopoietic stem cells for transplantation into unrelated recipients.

BACKGROUND: Transplantation of bone marrow from unrelated donors is limited by a lack of HLA-matched donors and the risk of graft-versus-host disease (GVHD). Placental blood from sibling donors can reconstitute hematopoiesis. We report preliminary results of transplantation using partially HLA-mismatched placental blood from unrelated donors. METHODS: Twenty-five consecutive patients, primarily children, with a variety of malignant and non-malignant conditions received placental blood from unrelated donors and were evaluated for hematologic and immunologic reconstitution and GVHD. HLA matching was performed before transplantation by serologic typing for class I HLA antigens and low-resolution molecular typing for class II HLA alleles. In donor-recipient pairs who differed by no more than one HLA antigen or allele, high-resolution class II HLA typing was done retrospectively. Fordonor-recipient pairs who were mismatched for two HLA antigens or alleles, high-resolution typing was used prospectively to select the best match for HLA-DRB1. RESULTS: Twenty-four of the 25 donor-recipient pairs were discordant for one to three HLA antigens. In 23 of the 25 transplant recipients, the infused hematopoletic stem cells engrafted. Acute grade III GVHD occurred in 2 of the 21 patients who could be evaluated, and 2 patients had chronic GVHD. In vitro proliferative responses of T cells and B cells to plant mitogens were detected 60 days after transplantation. With a median follow-up of 12 1/2 months and a minimal follow-up of 100 days, the overall 100-day survival rate among these patients was 64 percent, and the overall event-free survival was 48 percent. CONCLUSIONS: HLA-mismatched placental blood from unrelated donors is an alternative source of stem cells for hematopoietic reconstitution in children.

Adolescent↗
PubMed1993

In utero acute graft-versus-host disease in a neonate with severe combined immunodeficiency.

We describe a male neonate with severe combined immunodeficiency who at birth had acute graft-versus-host disease (GVHD) as a result of maternal-fetal transfusion during pregnancy. Several clinical signs helped establish this diagnosis. Findings of a skin biopsy specimen confirmed the diagnosis of acute GVHD. Immunologic evaluation disclosed an absence of T and B lymphocytes. Acute GVHD in severe combined immunodeficiency most often occurs during the first weeks of life; intrauterine occurrence is unusual.

Biopsy↗
PubMed1989

DQA1 restriction fragment length polymorphisms and insulin-dependent diabetes mellitus: a BglII fragment labels a subset of B8,DR3 haplotypes uniquely associated with insulin-dependent diabetes mellitus.

Class II restriction fragment length polymorphism studies of 38 pedigrees with multiple cases of insulin-dependent diabetes mellitus revealed the existence of a DQA1-related polymorphism that distinguishes two kinds of HLA-B8,DR3 haplotypes. One of these, characterized by the presence of DQA1-BglII 7.20 kb, was present in all 14 examples inherited by patients and in 6 of the 12 B8,DR3 haplotypes not so inherited. The apparently complete association between the presence of this fragment and the "affected" status of B8,DR3 haplotypes (p = 0.004) was confirmed in a separate group of 26 simplex pedigrees selected for the presence of this haplotype in the respective probands (combined p less than 0.0001).

Diabetes Mellitus, Type 1↗
PubMed1989

RFrAP: a computer program for analysis of complex HLA RFLPs. Assignment of restriction fragments to haplotypes by segregation analysis.

The availability of HLA class II cDNA probes has led to the development of a powerful method for the discrimination of genetic variation in this region of the major histocompatibility complex. There are problems with this approach which reduce its usefulness, including the hybridization of a probe with multiple restriction fragments (RFs) from the same locus or of two different cDNA probes with the same RF (cross-hybridizing). These problems may now be largely overcome by the relatively simple computer program presented here, which allows the entry, storage, and editing of phenotype data. It includes utilities for the automatic assignment of bands to haplotypes and also statistical functions to determine several types of correlations. The outputs are presented in a format familiar to HLA serologists and immunogeneticists. In addition, the data is stored in a manner that allows the user to easily prepare "ad hoc" figures and tables that illustrate the more complex relationships among bands and between them and other variables.

Computers↗
PubMed1988

Benzyl alcohol metabolism and elimination in neonates.

Reports on fatal benzyl alcohol poisoning in premature neonates implied that the toxicity may be due to larger doses per kilogram than for adults. It has been postulated that the load of benzoic acid (metabolite of benzyl alcohol) may exceed the capacity of the immature liver or kidney for detoxification through glycine conjugation to form hippuric acid. To test this hypothesis, 14 term and 9 preterm neonates receiving loading doses of phenobarbital containing benzyl alcohol were studied. Urine and serum benzoic and hippuric acid levels were measured by GC and HPLC methods, respectively. There was greater accumulation of benzoic acid in the serum of preterm compared to the term neonates which was reflected in higher normalized peak levels (2130.6 vs. 237.8 kg/l, p less than 0.001) and larger normalized AUCIV (1,253.2 vs. 483.0 kg.h/l, p less than 0.01). Furthermore, larger percentages of benzyl alcohol doses were found in urine as benzoic acid in preterm babies, while less hippuric acid appeared in their urine than term newborns. These results indicate that hippuric acid formation is deficient in preterm neonates. Although we did not encounter in our patients the specific toxic signs described as part of the benzyl alcohol toxicity syndrome, we cannot directly answer the issue of safety of 'low doses' of benzyl alcohol as found in some medications administered to neonates. This study confirms the immaturity of the benzoic acid detoxification process in premature newborns.

Benzoates↗
PubMed1987

Molecular characterization by high-resolution isoelectric focusing of the products encoded by the class II region loci of the major histocompatibility complex in humans. I. DR and DQ gene variants.

We describe a new approach to the analysis of the structural polymorphism of the DR beta, DQ alpha, and DQ beta polypeptide chains of human histocompatibility class II antigens. In comparison to conventional two-dimensional gel studies, this method provides sharper definition of the protein bands and side-by-side comparisons within the same gel, thereby permitting the detection of minor differences in the isoelectric points of the protein chains. Using this methodology we have analyzed the IEF polymorphism and the variability in the number of the DR beta chains encoded by different DR haplotypes. Twenty DR beta chain variants, which include the products of no less than two separate DR beta loci, have been thus far identified. Alleles at one of these loci are assumed to code for DR beta chains carrying the DR alloespecificities DR1, DR2, DR3, DR4, DR5, DRw6, DR7, and DR8. Alleles at a second DR beta locus encode DR beta chains that may be shared by serologically DR-different haplotypes and carry supertypic serologic specificities (i.e., DRw52 and DRw53). We also demonstrate here that the structural polymorphisms of the DQ alpha and DQ beta chains are more extensive than previously thought, report the characterization of 14 DQ beta variants, and define their relationship to the previously described DQw serologic specificities. In addition, we describe the class II haplotype associations observed for the different DR and DQ variants characterized.

Alleles↗
PubMed1984

Warfarin embryopathy--a case report.

This is a case report of an infant born with nasal hypoplasia, stippling of epiphyses, and toe deformities. This embryopathy is due to maternal ingestion of Warfarin during pregnancy. Other defects including ophthalmologic and neurologic abnormalities also occur, but the nasal malformation is the only constant clinical feature.

Abnormalities, Drug-Induced↗
PubMed1983

Use of self-generated and supplied visuals as mnemonics in gifted children's learning.

In accordance with ancient belief and recent research, we hypothesized that self-generated imagery techniques of gifted children would be superior to supplied (experimenter-provided) visuals in facilitating recall and recognition on a memory task. 27 high-potential students in Grades 4 to 6 were divided into three treatment groups to investigate the effects of rote repetition, self-generated visualization, and supplied visuals on the memorization of concrete noun-word pairs. Perhaps because even gifted children do not know how to construct good visual images without training and practice, our hypothesis was not supported. The supplied visual condition produced significantly better results than did either of the other treatment conditions, implying that the utilization of appropriate techniques helps gifted children learn certain memory tasks. However, one wonders if effective instruction in the development of self-generated mnemonic techniques might not be of greater benefit to young learners of such tasks.

Child↗
PubMed1981

HLA antigens and islet cell antibodies in gestational diabetes.

The HLA antigens of 136 patients with gestational diabetes are compared with control populations. No significant variations are observed in their frequencies, particularly for those antigens associated with Type 1 diabetes mellitus. Islet cell antibodies have also been studied in the serum of 52 of these patients and 20 of them were positive, whereas only one of 37 pregnant nondiabetic women had such antibodies (chi 2 = 15.2). A very high association between ICA and DR3 and DR4 was encountered (chi 2 = 17, with two df); half of the patients positive for either one of these antigens were ICA positive. These results indicate that ICA associates equally with DR3 and DR4, against the hypothesis that this expression of autoimmunity is more a characteristic of DR3- than of DR4-associated genetic susceptibility. These patients will be followed to determine if the ICA+ individuals are at increased risk for the development of insulin-dependent diabetes.

Adult↗