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C Thomas

Publications and source records attributed to C Thomas.

At least 217 records · Page 12Linked to original sources
PubMed1996

[Langerhans cell histiocytosis].

Histiocytosis X, or Langerhans cell histiocytosis (LCH), is a rare disease, with an estimated incidence of 1/200,000 per year in children under 15 years of age. It has a wide clinical spectrum, from single bone involvement (eosinophilic granuloma) to multisystemic disease with organ failure. The treatment of LCH is still controversial. While single system disease may spontaneously recover or requires minimal treatment, some multisystemic disease with organ dysfunction may resist systemic chemotherapy. The mortality rate in this latter subgroup of patients is relatively high and reaches 40% of the cases. A rational approach to the treatment of LCH is based on a better understanding of clinical and pathophysiological features. A prospective multicentre trial including scientific research should be planned, in order to determine the optimal treatment of LCH and to ameliorate the prognosis of the severe unresponsive form of the disease.

Child, Preschool↗
PubMed1996

Association between HLA-DM and HLA-DR in vivo.

The exchange of HLA class II-associated invariant chain peptides (CLIP) for cognate peptide is catalyzed by HLA-DM under acidic conditions in vitro by an unknown mechanism. Here, we show an association between HLA-DM and HLA-DR in vivo by coprecipitation of the two heterodimers. The association is favored at low pH and in the nonionic detergent digitonin. Most DM-DR complexes are isolated from dense subcellular fractions. Recovery of HLA-DM by the conformation-dependent DR3 monoclonal antibody 16.23 suggests an association with HLA-DR heterodimers beyond the stage at which CLIP is released. The additional N-linked glycan on mutant DR3 molecules isolated from the 10.24.6 cell line, which interferes with DM-enhanced CLIP release from DR3 in vitro, also affects the DM-DR interaction.

HLA-D Antigens↗
PubMed1996

A phase II trial of partially incompatible bone marrow transplantation for high-risk acute lymphoblastic leukaemia in children: prevention of graft rejection with anti-LFA-1 and anti-CD2 antibodies. Société Française de Greffe de Moelle Osseuse.

Bone marrow transplantation (BMT) from matched sibling donors has been useful for the treatment of acute lymphoblastic leukaemia in children with a poor prognosis but is not available to more than two-thirds of patients who do not have a matched allogeneic donor. This study was undertaken to assess one strategy of marrow graft rejection prevention when alternative marrow sources such as HLA-phenoidentical unrelated volunteers and HLA-partially incompatible relatives were used. Results have been compared with two matched groups of children with the same risks factors and disease status who underwent HLA-genoidentical or autologous BMT. The conditioning regimen was the same for the three groups of patients; in the study group anti-LFA-1 and anti-CD2 monoclonal antibodies combined with T-cell depletion of the marrow was added to prevent graft rejection and graft-versus-host disease. Nineteen patients were included and followed for a median of 25 months (14 months to 3 years). Bone marrow engraftment occurred in 83% of the evaluable patients. Post-transplantation infectious diseases were the most frequent causes of death in the study group, occurring in 31% of patients. No fatal infections occurred in the two control groups. Post-transplantation relapse of leukaemia occurred in 26% of study group's patients, in 58% of autologous BMT control group's patients and 5% of HLA-genoidentical allogeneic group's patients. The event-free survival was 83% in the HLA-genoidentical control group, and 30% and 24% in the study group and in the autologous control group, respectively. In conclusion, a high rate of engraftment was achieved by the use of anti-LFA-1 and anti CD2 antibodies. Occurrence of a long-lasting immunodeficiency, however, led to a high incidence of lethal infections and relapses. Combined approaches are therefore to be investigated accelerating immune reconstitution after transplantations of T-depleted HLA partially incompatible marrow.

Adolescent↗
PubMed1996

A sigma ligand, SR 31747A, potently modulates Staphylococcal enterotoxin B-induced cytokine production in mice.

Sigma receptors originally described in distinct regions of the central nervous system are expressed on cells of the immune system. A sigma ligand, SR 31747A, was observed here to inhibit in vitro the Staphylococcal enterotoxin B (SEB)-driven lymphocyte proliferation. In mice, the drug confers a potent protection against the lethality induced by SEB, stimulates the SEB-induced serum release of interleukin (IL)-10 and inhibits at the same time the systemic release of IL-2, IL-4, granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-6 and tumour necrosis factor-alpha (TNF-alpha). The enhancement of IL-10 production by this compound is also effective in nude mice treated with SEB, indicating that IL-10 of T-cell origin is not involved in this process. The finding that a sigma ligand protects against the SEB-induced toxicity provides insights into the clinical use of this family of compounds, particularly in food poisoning and septic shock where Staphylococcal enterotoxins are involved. The observation that this compound stimulates IL-10 synthesis indicates that it could be a potent regulatory agent of chronic inflammatory diseases.

Animals↗
PubMed1996

Effects of graded hypothermia on outcome from brain ischemia.

The effects of mild (34 degrees C) and moderate (31 degrees C) hypothermia on the electroencephalogram, cerebral blood flow and outcome from incomplete brain ischemia were compared to normothermia (37 degrees C) in the rat. Rats were anesthetized with fentanyl (25 mu g kg(-1) h(-1)) and 70 percent nitrous oxide in oxygen. Ischemia was produced by right carotid ligation combined with hemorrhagic hypotension to 25 mmHg for 30 min. CBF was measured in the right parietal cortex by laser Doppler. Neurologic outcome was measured daily for 3 days after ischemia and histopathology determined at the end of the study. Before ischemia, neither EEG nor CBF were changed by hypothermia compared to normothermic controls. Total EEG and beta EEG (12.5-32 Hz) were abolished and CBF decreased by 70 percent during ischemia. During a 2.5 h recovery period total EEG and beta EEG activity recovered better with moderate hypothermia compared to normothermia. Recovery of cerebral blood flow was not significantly different between the treatment groups. Neurologic and histopathologic outcome were improved in rats receiving moderate hypothermia compared to normothermic controls. These results show that during severe incomplete ischemia, hypothermia has a graded effect on outcome which is consistent with its effects on brain metabolism.

Animals↗
PubMed1996

The relation of religious preference and practice to depressive symptoms among 1,855 older adults.

Religious devotion is a complex phenomenon but a potentially important source of support and meaning in the lives of older adults. Nonetheless, attendance at religious services and religious preference (affiliation) have received relatively little prominence in epidemiological studies of late life mental illness despite their relative case of measurement. We examined differences in the prevalence and course of depressive symptoms and associated characteristics among 1,855 older community residents who expressed a Jewish, Catholic, or other religious preference. At baseline, Jewish religious preference was associated with a twofold elevation in the prevalence of depressive symptoms compared to Catholics. Lack of attendance at religious services was associated with greater prevalence of depression among all groups, significantly so among Catholics. The relationship of depression with Jewish religious preference and with failure to attend services could not be accounted for by measures of age, gender, health, disability, or social support. Twenty-four months following baseline, Jewish religious preference was associated with the emergence of depressive symptoms and remained significant when the effects of age, gender, health, disability, and social support were controlled. Failure to attend services was associated with both the emergence and persistence of depression but did not remain significant once the effects of other characteristics were controlled. For both religious and health care institutions, these findings have implications for the prevention, recognition, and treatment of late life mental illness.

Aged↗
PubMed1996

Skin lesions revealing neonatal acute leukemias with monocytic differentiation. A report of 3 cases.

Acute myelo-monoblastic (AMML) and acute monoblastic (AML) leukemias have a bad prognosis, especially in children when occurring in the first months of life. We report 3 cases of such leukaemias in which skin lesions preceded and revealed the leukemia. For the 3 infants, cutaneous lesions appeared about one month before the other signs of leukaemia (2 AML and 1 AMML). Skin biopsies from all 3 infants revealed a heavy dermic infiltration by large cells with round or irregular vesicular nuclei and abundant pale cytoplasm. These atypical cells did not express any lymphoid markers but reacted strongly with monocytic-macrophagic antibodies (CD68, CD13 and CD14). Two infants were treated by mitoxanthrone and cytarabine with complete remission. The third one was not treated because of a very poor general status. Skin involvement is frequent in these nonlymphoid leukaemias (30% to 50% of cases). In only 7% of cases, leukemic skin lesions precede and reveal the other signs of leukemia by weeks or months. Then, it is very important to repeat the blood cell counts and to biopsy the skin lesions in order to make a diagnosis of leukemia as early as possible.

Cell Differentiation↗
PubMed1996

Molecular subtype distribution of Cryptococcus neoformans in four areas of the United States. Cryptococcal Disease Active Surveillance Group.

To improve understanding of the epidemiology of cryptococcal disease, we analyzed the multilocus genotype distribution of 358 Cryptococcus neoformans isolates obtained from 251 patients through active surveillance in four U.S. geographic areas from 1992 through 1994. Isolates of the predominant enzyme electrophoretic type (ET), ET-1, were recovered in significantly greater proportion from Atlanta, Ga., Houston, Tex., and all major metropolitan areas of Alabama than from San Francisco, Calif. ET-2 and ET-7 complex (serotype AD) isolates were recovered predominantly from San Francisco. ET-3 was recovered less frequently from San Francisco than from the three other locations. These findings may reflect geographic differences in exposure to environmental strains or the identification of previously unrecognized C. neoformans clusters. Analysis by random amplified polymorphic DNA-PCR subtyping further divided 67 ET-1 isolates into 19 additional subtypes, none of which could be associated with a particular geographic region. Multiple isolates from the same patient always revealed the same multilocus enzyme electrophoresis and random amplified polymorphic DNA subtypes. No differences in subtype distribution were found when isolates from AIDS patients were compared with those from persons without or with another underlying disease, although one C. noeformans var. gattii isolate was obtained from an AIDS patient. When body site distribution was analyzed, ET-4 was disproportionately recovered from skin or surface body sites. Evidence for linkage disequilibrium in this fungal population suggests that virulent C. neoformans possesses a clonal population structure. Continued application of molecular subtyping methods will be useful in tracking the source, transmission, and relative virulence of different C. neoformans strains.

AIDS-Related Opportunistic Infections↗
PubMed1996

Outcomes following acute exacerbation of severe chronic obstructive lung disease. The SUPPORT investigators (Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments)

In order to describe the outcomes of patients hospitalized with an acute exacerbation of severe chronic obstructive pulmonary disease (COPD) and determine the relationship between patient characteristics and length of survival, we studied a prospective cohort of 1,016 adult patients from five hospitals who were admitted with an exacerbation of COPD and a PaCO2 of 50 mm Hg or more. Patient characteristics and acute physiology were determined. Outcomes were evaluated over a 6 mo period. Although only 11% of the patients died during the index hospital stay, the 60-d, 180-d, 1-yr, and 2-yr mortality was high (20%, 33%, 43%, and 49%, respectively). The median cost of the index hospital stay was $7,100 ($4,100 to $16,000; interquartile range). The median length of the index hospital stay was 9 d (5 to 15 d). After discharge, 446 patients were readmitted 754 times in the next 6 mo. At 6 mo, only 26% of the cohort were both alive and able to report a good, very good, or excellent quality of life. Survival time was independently related to severity of illness, body mass index (BMI), age, prior functional status, PaO2/FI(O2), congestive heart failure, serum albumin, and the presence of cor pulmonale. Patients and caregivers should be aware of the likelihood of poor outcomes following hospitalization for exacerbation of COPD associated with hypercarbia.

APACHE↗
PubMed1996

MRI and neuropsychological differences in early- and late-life-onset geriatric depression.

We sought to determine whether geriatric patients with late-life-onset major depression have more subcortical hyperintensities on MRI and greater cognitive impairment than age-matched geriatric patients with early-life-onset major depression, suggesting that subcortical disease may be etiologic in late-life depression. Most negative studies of the clinical significance of subcortical hyperintensities on MRI in geriatric patients have sampled from a restricted range of subjects, have employed limited batteries of neuropsychological tests, or have not quantified MRI changes; the present study attempted to address these limitations. Thirty subjects from a geriatric psychiatry inpatient service who were over 60 years of age and presented with major depression were divided into groups with onset of first depression after age 60 (mean = 72.4 years, 15 women, 0 men), and onset of first depression before age 60 (mean = 35.8 years, 12 women, 3 men). Quantitative analysis of MRI yielded the volume of: periventricular hyperintensities (PVH) and deep white-matter hyperintensities (DWMH). Subjects were administered a neuropsychological battery and measures of depression by raters blind to age of onset. The late-onset group had significantly more PVH and DWMH. They were also more impaired on executive and verbal and nonverbal memory tasks. Discriminant analysis using the severity or subcortical signal hyperintensities on MRI, cognitive index, and depression scores correctly predicted late versus early onset of depression in 87% of the early-onset group and 80% of the late-onset group. These findings suggest that late-life-onset depression may be associated with an increased severity of subcortical vascular disease and greater impairment of cognitive performance.

Adult↗
PubMed1996

Bone marrow transplantation from genetically HLA-nonidentical donors in children with fatal inherited disorders excluding severe combined immunodeficiencies: use of two monoclonal antibodies to prevent graft rejection.

OBJECTIVE: For children with life-threatening inborn errors of metabolism without a matched related bone marrow donor, transplantation from an HLA genetically nonidentical donor is the only therapeutic option. To reduce the high risk of graft rejection in this setting without increasing the conditioning regimen, a protocol based on the infusion of an antiadhesion antibody directed against the CD11a (leukocyte function-associated antigen 1 [LFA-1]) molecule was performed by the European Bone Marrow Transplantation-European Society for Immunodeficiency group with promising results. To optimize engraftment, and thereby survival, further, the additional blockade of a second important leukocyte adhesion and signalization pathway mediated by the CD2 and LFA-3 interaction was attempted in a multicenter protocol conducted by the European Bone Marrow Transplantation-European Society for Immunodeficiency group. Results of this study (ie, engraftment and survival) were compared with a historical control group that received the anti-LFA-1 antibody alone. Factors that may have affected engraftment and survival were also considered in this study. METHODS: Forty-four children with inborn errors, including inherited immunodeficiencies (excluding severe combined immunodeficiencies), Chédiak-Higashi syndrome, familial hemophagocytic lymphohistiocytosis, and malignant osteopetrosis, received bone marrow from HLA-nonidentical related donors or from HLA-identical unrelated donors at 13 European centers between August 1990 and June 1993. Bone marrow was depleted of T cells by use of either erythrocyte (E) rosetting or monoclonal antibodies (MoAbs) to prevent graft-versus-host disease. The conditioning regimen consisted of busulfan and cyclophosphamide for all patients plus etoposide for patients with osteopetrosis, familial hemophagocytic lymphohistiocytosis, and Chédiak-Higashi syndrome. Infusions of MoAbs specific for the CD11a and the CD2 molecules were started 4 and 3 days, respectively, before and continued through the first 10 and 11 days, respectively, after bone marrow transplantation (a total of 14 injections). RESULTS: The overall sustained engraftment rate was 69.8%, with full chimerism in 80.6% of patients and no late graft rejection with the use of two MoAbs versus 65.7% and 58.1%, respectively, in the control group, in which only one MoAb was infused. The overall actuarial survival rate with a functional graft was 40.9%, with a mean follow-up of 39.3 months with two MoAbs versus 37.8% with one. The engraftment rate was significantly influenced by the T-cell depletion method, with better results for recipients of E rosette- depleted marrow (78.6% vs 20% for Campath 1-M plus complement-depleted marrows). Graft-versus-host disease and the kinetics of immune reconstitution were similar in both groups. CONCLUSIONS: The overall engraftment rate and overall survival rate with engraftment in patients treated with anti-LFA-1 and anti-CD2 were similar to those in patients treated with anti-LFA-1 antibody alone. However, although the number of patients is too small to draw definitive conclusions, results from the combined use of the two MoAbs indicates a trend toward better engraftment and survival after infusion of E rosette-depleted marrow. Further improvement in survival would demand additional strategies to hasten immunologic recovery.

Antibodies, Monoclonal↗
PubMed1995

Variations of soluble intercellular cell adhesion molecule 1 (sICAM-1) in serum of adult volunteers.

Soluble cell adhesion molecules such as sICAM-1 in serum and other biological fluids are suggested as being useful diagnostic parameters for a variety of diseases. Since increased concentrations during diseases are frequently less pronounced compared to other parameters, we tested whether it would be necessary to align the time of blood collection during the course of a clinical trial. In the 9 volunteers of our trial we found a statistically significant effect at the point in time of blood collection and corresponding serum concentrations of sICAM-1 (p < 0.01). The deviation of the concentrations at a certain time from the daily mean in each individual was seen to be as high as 15%. Our data suggest that daytime variations of serum sICAM-1 concentrations should be taken into consideration when longitudinal observations are planned.

Adult↗
PubMed1995

Results of allogeneic bone marrow transplantation in patients with leukocyte adhesion deficiency.

We have retrospectively analyzed the outcome of bone marrow transplantation (BMT) in 14 patients with leukocyte adhesion deficiency (LAD) performed in two centers between 1981 and 1993. Five patients received BMT from HLA-identical donors. Nine received T-depleted marrow from two HLA antigen- or haplotype-incompatible parents. Conditioning regimen consisted of chemotherapy exclusively in 13 patients and associated with total body irradiation (TBI) in one patient. In five cases, failure of engraftment occurred as a result of either insufficient myeloablation (n = 3) or, possibly, graft rejection in two cases of moderate phenotype of LAD. The second conditioning regimen consisted of TBI and chemotherapy with the use of anti-lymphocyte function-associated antigen 1 (LFA-1) and anti-CD2 monoclonal antibodies for patients with the moderate phenotype of LAD. These patients were successfully retransplanted. Eight patients developed acute graft-versus-host disease (GVHD). Chronic GVHD occurred in five cases. GVHD led to the death of three patients. Ten patients are alive and well 12 months to 12 years after BMT. Chimerism is full in six of these patients and mixed but stable in four with variable proportion of donor leukocytes. One patient with less than 15% donor leukocytes has mild gingivitis, while the others are well. Sequelae from BMT are limited in two cases to growth retardation caused by TBI. Success of BMT in cases of LAD including seven of nine recipients of HLA nonidentical marrow indicates that this procedure can be proposed as a curative approach to LAD regardless of an available HLA-identical donor. Great care should be taken in GVHD prophylaxis and treatment.

Adolescent↗