Biomedical subjects

C Peters

Publications and source records attributed to C Peters.

At least 91 records · Page 5Linked to original sources

PubMed1999

Cathepsin J, a novel murine cysteine protease of the papain family with a placenta-restricted expression.

A novel mouse cysteine protease of the papain family was identified by searching the dbEST database. A 1.28 kb full-length cDNA was obtained which contains an open reading frame of 999 nucleotides and encodes a predicted polypeptide of 333 amino acids. The deduced polypeptide exhibits features characteristic of cysteine proteases of the papain type including the highly conserved residues of the catalytic triad, and was hence named cathepsin J. Cathepsin J represents the murine homologue of a previously described rat cathepsin L-related protein. Mature cathepsin J shows 59.3% identity to mouse cathepsin L and contains the characteristic ER(F/W)NIN motif within the propeptide indicating that this protease belongs to the subgroup of cathepsin L-like cysteine proteases. Northern blot analysis of various tissues revealed a placenta-restricted expression. This expression pattern may suggest a role of cathepsin J in embryo implantation and/or placental function. Ctsj was mapped to mouse chromosome 13 in the vicinity of cathepsin L suggesting that cathepsin J may have arisen by gene duplication from cathepsin L or a common ancestral gene.

Amino Acid Sequence↗

PubMed1999

Cathepsin D targeted by acid sphingomyelinase-derived ceramide.

Ceramide has been recognized as a common intracellular second messenger for various cytokines, growth factors and other stimuli, such as CD95, chemotherapeutic drugs and stress factors. To understand the role of ceramide during apoptosis and other cellular responses, it is critically important to characterize direct targets of ceramide action. In this paper, we show that ceramide specifically binds to and activates the endosomal acidic aspartate protease cathepsin D. Direct interaction of ceramide with cathepsin D results in autocatalytic proteolysis of the 52 kDa pre-pro cathepsin D to form the enzymatically active 48/32 kDa isoforms of cathepsin D. Acid sphingomyelinase (A-SMase)-deficient cells show decreased cathepsin D activity, which could be reconstituted by transfection with A-SMase cDNA. The results of our study identify cathepsin D as the first endosomal ceramide target that colocalizes with and may mediate downstream signaling effects of A-SMase.

Animals↗

PubMed1999

Association analysis of exonic variants of the gene encoding the GABAB receptor and idiopathic generalized epilepsy.

The gene encoding the GABAB receptor (GABABR1) maps close to the HLA-F locus on chromosome 6p21.3 in the same region to which a major susceptibility locus for common subtypes of idiopathic generalized epilepsy (IGE), designated as EJM1, has been localized. Moreover, animal models suggest that the GABAB receptor plays a critical role in the epileptogenesis of absence seizures. Accordingly, the present association study tested the candidate gene hypothesis that genetic variants of the human GABABR1 gene confer susceptibility to common subtypes of IGE. Three DNA sequence variants in exons 1a1, 7, and 11 of the GABABR1 gene were assessed by PCR-based restriction fragment length polymorphisms in 248 unrelated probands of German descent, comprising 72 patients with juvenile myoclonic epilepsy (JME), 46 patients with idiopathic absence epilepsy (IAE), and 130 control subjects without a history of epileptic seizures and lack of generalized spike-wave discharges in their electroencephalogram. The results revealed no evidence for an allelic association of any of the GABABR1 sequence variants with either JME or IAE (P > 0.18). Thus, we failed to demonstrate that any of the three exonic GABABR1 variants themselves, or other so-far unidentified mutations, which are in strong linkage disequilibrium with the investigated variants, are involved in the pathogenesis of common IGE subtypes.

Adolescent↗

PubMed1999

Control of the terminal step of intracellular membrane fusion by protein phosphatase 1.

Intracellular membrane fusion is crucial for the biogenesis and maintenance of cellular compartments, for vesicular traffic between them, and for exo- and endocytosis. Parts of the molecular machinery underlying this process have been identified, but most of these components operate in mutual recognition of the membranes. Here it is shown that protein phosphatase 1 (PP1) is essential for bilayer mixing, the last step of membrane fusion. PP1 was also identified in a complex that contained calmodulin, the second known factor implicated in the regulation of bilayer mixing. The PP1-calmodulin complex was required at multiple sites of intracellular trafficking; hence, PP1 may be a general factor controlling membrane bilayer mixing.

Biological Transport↗

PubMed1999

Transplantation of related and unrelated umbilical cord blood stem cells in Austria. Austrian Working Party for Stem Cell Transplantation. Austrian Society of Hematology and Oncology.

Allogeneic bone marrow transplantation is limited by the availability of suitable HLA-matched donors and the risk of graft versus host disease (GvHD). In an attempt to overcome these limitations umbilical cord blood (UCB), has become a further alternative. UCB transplantations in Austria were started in 1991. As of September 31, 1998, six patients have been transplanted. Diagnoses were severe aplastic anaemia (SAA) (n = 2), acute lymphoblastic leukaemia (ALL) (n = 1), familial hemophagocytic syndrome (FHL) (n = 2) and chronic myelomonocytic leukaemia (CMML) (n = 1). Three patients received UCB grafts from HLA-identical siblings and three patients from unrelated donors, of whom two were disparate at two HLA loci (A/B) and one mismatched at one locus (C). Five patients were engrafted with complete donor hematopoiesis, with a median time of 26.5 days (range 14 to 39 days) to an ANC count of > or = 0.5 x 10(9)/L and a median time of 42.5 days (range 24 to 67 days) to a platelet count of > or = 20 x 10(9)/L. One patient with FHL had partial engraftment and died due to reactivation of cytomegalovirus (CMV) infection and CMV pneumonia on day +25. Of the five patients surviving the post-transplant period, one with CMML had a relapse on day +128 and died after a HLA-matched bone marrow transplantation from the same sibling donor in the second relapse. Another patient with ALL relapsed on day +200 but is still alive under palliative treatment; one patient with SAA showed graft rejection and autologous hematopoietic reconstitution and later had a successful CD34(+)-selected allogeneic peripheral stem cell transplant from a C-locus mismatched unrelated donor. Two patients (one with SAA and one with FHL) are alive with complete remission of the underlying disease. This report reflects the experience and results of UCB transplantation in Austria and discusses the position of UCB transplantation in the context of the other stem cell alternatives available today.

Anemia, Aplastic↗

PubMed1999

G-CSF versus GM-CSF for stimulation of peripheral blood progenitor cells (PBPC) and leukocytes in healthy volunteers: comparison of efficacy and tolerability.

This study compared two recombinant human (rh) hematopoietic growth factors in healthy volunteers for stem cell stimulation. Granulocyte colony-stimulating factor (G-CSF, n=9) or granulocyte-macrophage colony-stimulating factor (GM-CSF, n=8) was given subcutaneously for 5 days (5 microg/kg/day). Controls (n=5) received no growth factor. Laboratory parameters and side effects were monitored for 8 days. Within 24 h, both cytokines led to a rapid increase of leukocytes, the majority of which were granulocytes. Compared with the controls (n=5), the increase on day 5 in the G-CSF/GM-CSF groups was 37-/10-fold (CD34+ cells), 5.2-/2.4-fold (leukocytes), 7.2-/3.0-fold (granulocytes), 7.4-/4.4-fold (monocytes), 1.7-/1.1-fold (lymphocytes), 9.8-/2.7-fold (basophils), 2.3-/9.6-fold (eosinophils), and 1.9-/1.6-fold (reticulocytes). The mobilization of myeloblasts, promyelocytes, myelocytes, and metamyelocytes coincided with the pronounced increase of CD34 + PBPC observed on day 4. Serum levels of uric acid (UA) and lactic dehydrogenase (LDH) increased under G-CSF, and platelets decreased after G-CSF discontinuation. Rash at the injection site occurred in 50% of the GM-CSF-treated volunteers. Seven volunteers in the GM-CSF group and six in the G-CSF cohort complained of flu-like symptoms, including musculoskeletal pain. We conclude that, in terms of tolerance and mobilization of CD34+ cells and leukocytes, G-CSF is superior to GM-CSF, but higher levels of UA and LDH and late decrease in platelets make monitoring of these parameters necessary.

Adult↗

PubMed1999

Bone marrow-derived mesenchymal stem cells remain host-derived despite successful hematopoietic engraftment after allogeneic transplantation in patients with lysosomal and peroxisomal storage diseases.

Human bone marrow contains mesenchymal stem cells (MSCs) that can differentiate into various cells of mesenchymal origin. We developed an efficient method of isolating and culture expanding a homogenous population of MSCs from bone marrow and determined that MSCs express alpha-L-iduronidase, arylsulfatase-A and B, glucocerebrosidase, and adrenoleukodystrophy protein. These findings raised the possibility that MSCs may be useful in the treatment of storage disorders. To determine if donor derived MSCs are transferred to the recipients with lysosomal or peroxisomal storage diseases by allogeneic hematopoietic stem cell (HSC) transplantation, we investigated bone marrow derived MSCs of 13 patients 1-14 years after allogeneic transplantation. Highly purified MSCs were genotyped either by fluorescence in situ hybridization using probes for X and Y-chromosomes in gender mis-matched recipients or by radiolabeled PCR amplification of polymorphic simple sequence repeats. Phenotype was determined by the measurement of disease specific protein/enzyme activity in purified MSCs. We found that MSCs isolated from recipients of allogeneic HSC transplantation are not of donor genotype and have persistent phenotypic defects despite successful donor type hematopoietic engraftment. Whether culture expanded normal MSCs can be successfully transplanted into patients with storage diseases and provide therapeutic benefit needs to be determined.

Case-Control Studies↗

PubMed1999

Noggin is a mesenchymally derived stimulator of hair-follicle induction.

The induction of developmental structures derived from the ectoderm, such as the neural tube or tooth, occurs through neutralization of the inhibitory activity of members of the bone-morphogenetic protein (BMP) family by BMP antagonists. Here we show that, during hair-follicle development, the neural inducer and BMP-neutralizing protein Noggin is expressed in the follicular mesenchyme, that noggin-knockout mice show significant retardation of hair-follicle induction, and that Noggin neutralizes the inhibitory action of BMP-4 and stimulates hair-follicle induction in embryonic skin organ culture. As a crucial mesenchymal signal that stimulates hair-follicle induction, Noggin operates through antagonistic interactions with BMP-4, which result in upregulation of the transcription factor Lef-1 and the cell-adhesion molecule NCAM, as well as through BMP4-independent downregulation of the 75 kD neurotrophin receptor in the developing hair follicle.

Animals↗

PubMed1999

Organ toxicity and quality of life after allogeneic bone marrow transplantation in pediatric patients: a single centre retrospective analysis.

One hundred and fifty five pediatric patients underwent allogeneic bone marrow transplantation between 1980 and 1996 in the St Anna Children's Hospital in Vienna with an overall survival of 52.3% (81 patients). Seventy-three patients with a minimum observation time of 1 year (1-13 years, median: 4.6) were analyzed retrospectively for chronic GVHD, organ toxicity (WHO score), growth and pubertal development. Chronic GVHD was diagnosed in 20 patients (27.3%), being extensive in 17 cases. Maximum organ toxicity was WHO III in two patients (3%) and WHO II in 11 patients (15%) 1 year after BMT and WHO III in one patient (2%) and WHO II in five patients (11%) 3 years after BMT. Impaired growth and pubertal development were detected in more than 30% 3 years after BMT. As all patients presented with a Karnofsky or Lansky score of more than 80%, they were asked to complete a questionnaire comprising 12 questions concerning physical state of health and psychosocial state of health. Restricted contacts were classified as imposing a severe handicap by six patients (8%), restriction in mobility and 'normal life activities' by three patients (4%) and two patients classified themselves as severely physically handicapped. Most patients (75%) reported no physical or psychical impairment.

Adolescent↗

PubMed1999

High spontaneous IL-10 production in unrelated bone marrow transplant recipients is associated with fewer transplant-related complications and early deaths.

Interleukin 10 (IL-10) is a potent inhibitor of proliferative T cell responses toward alloantigens, and suppresses the production of pro-inflammatory cytokines which are important in cellular activation and recruitment to sites of inflammation. Because of these properties, we hypothesized that high IL-10 production in patients prior to BMT may predict a better outcome. To investigate this, peripheral blood mononuclear cells (PBMNC) were obtained from 58 recipients (11 autologous, 25 related donor (RD), and 22 unrelated donor (URD)), prior to conditioning therapy. PBMNC were cultured for 24 h in the presence and absence of lipopolysaccharide (LPS) and culture supernatants were assayed for IL-10 using an ELISA method. Spontaneously produced and LPS-stimulated IL-10 levels were correlated with the development of transplant-related complications (TRC) including grade II-IV acute GVHD, veno-occlusive disease, idiopathic pneumonia syndrome and multi-organ dysfunction syndrome, and with death before day 100. For the autologous group, there were no TRC and only one death prior to day 100; therefore, no statistical comparisons to IL-10 levels could be made. In the RD group, 36% developed one or more TRC and 24% died before day 100; however, there were no statistically significant associations between spontaneous or LPS-induced IL-10 levels. In URD patients 41% developed TRC and 55% died prior to day 100. In this group, higher levels of spontaneous IL-10 production were associated with a lower overall occurrence of TRC (P = 0.03) and early death (P = 0.04). Our data would indicate that higher levels of IL-10 production prior to URD BMT may predict fewer TRC, as well as early deaths. The hypothesis that high IL-10 production prior to BMT may decrease complications following URD BMT warrants further testing.

Adolescent↗

PubMed1999

Psychosocial adjustment of pediatric patients after allogeneic stem cell transplantation.

The purpose of this study was to assess the psychosocial adjustment of patients who had been treated with allogeneic stem cell transplantation (SCT) in our clinic. Selection criteria for patients were to be aged 14-30 years at the time of the follow-up, to be at least 2 years post-SCT and to have a very good knowledge of German. Among 31 eligible patients, 26 participated (84% response rate). The patients were between 15 and 27 years old and were on average 7 years (range 2-13) post-SCT. Research instruments consisted of a demographic questionnaire and various subscales of established psychological measures for which data from a sample of bone cancer survivors and population norms were available. About 35% of patients showed high levels of anxiety, 62% appeared to be extremely sensitive and vulnerable, and 35% showed strong, unfulfilled needs in their love lives. In the other domains tested (self-esteem, family and peer relationships, school/vocational performance, etc), no noticeable differences were found between the subjects and comparable populations. There was no significant association between psychosocial outcome and demographic features or clinical data. Our results suggest that patients who underwent SCT in their childhood or adolescence are at risk of developing long-term emotional or social problems. Due to the retrospective design of our study and the small sample size, no predictive factors for psychosocial distress could be identified.

Adolescent↗

PubMed1999

Transplantation of highly purified peripheral blood CD34+ cells from HLA-mismatched parental donors in 14 children: evaluation of early monitoring of engraftment.

HLA-mismatched family members may represent an important cell source for patients that require stem cell transplantation but lack both a matched sibling donor and a closely matched unrelated donor. We report the outcome of 19 transplantations from HLA two- or three- loci mismatched parental donors in which 14 pediatric patients with hematological malignancies or other disorders, received a median of 21.5 x 106 (range, 5.4-58) highly purified CD34+peripheral blood stem cells (PBSC), as well as 4.7 x 104 (range, 0.4-12) donor T cells per kg body weight. T cell depletion was performed using a two-step CD34-positive selection on two different magnetic beads devices. Ten of 14 patients presented with rapid myeloid engraftment. The four patients who presented with graft failure (two non-engraftments, two rejections) received a second stem cell graft and one a third. Graft rejection was detected early by polymerase chain reaction (PCR) analysis of FACS-sorted T cells. Eight of the 14 patients are still alive after a median observation period of 15. 6 months (range, 3-31.3) with full donor chimerism in all hematopoietic cell lineages. No acute organ graft-versus-host disease (GVHD) and no chronic GVHD have occurred. One patient experienced relapse of leukemia. We conclude that transplantation of allogeneic PBSC from haploidentical donors will open new perspectives for pediatric patients for whom an HLA-matched stem cell graft is not available. Close monitoring of recipient and donor hematopoiesis might be of clinical value, to recognize early engraftment or rejection.

Adolescent↗

PubMed1999

Leucocyte transfusions from rhG-CSF or prednisolone stimulated donors for treatment of severe infections in immunocompromised neutropenic patients.

Sepsis in profound neutropenia after chemotherapy is associated with high mortality despite appropriate antibacterial or antifungal treatment. In a prospective phase I/II study we evaluated the feasability and efficacy of leucocyte transfusions (LT) in patients with malignancies or haematological disorders who were suffering from severe bacterial or fungal infection during therapy-related bone marrow aplasia. 30 patients with severe neutropenia and clinical signs of life-threatening sepsis not responding to adequate treatment, received LT from rhG-CSF-stimulated family donors or from prednisolone-primed volunteers. A total of 301 LT were administered. The median number of LT per patient was seven (range three to 65), the median duration of LT treatment was 8 d (range 2-35). The white cell count (WBC), absolute neutrophil count (ANC) and lymphocyte count of the concentrates from rhG-CSF-stimulated donors were significantly higher than those from prednisolone-primed volunteers (P = 0.0001). Despite the critical condition of the patients, LT were generally well tolerated. Only 39 (12.9%) LT were associated with adverse reactions. The transfusion of leucocytes collected by continuous flow leukapheresis from both rhG-CSF and prednisolone stimulated donors resulted in a measurable increment of the peripheral leucocyte and ANC counts in our patients. On day 100 after the first LT, 20/30 patients were alive with complete clearance of the infection.

Adolescent↗

PubMed1999

Field investigations of an outbreak of Ebola hemorrhagic fever, Kikwit, Democratic Republic of the Congo, 1995: arthropod studies.

During the final weeks of a 6-month epidemic of Ebola hemorrhagic fever in Kikwit, Democratic Republic of the Congo, an extensive collection of arthropods was made in an attempt to learn more of the natural history of the disease. A reconstruction of the activities of the likely primary case, a 42-year-old man who lived in the city, indicated that he probably acquired his infection in a partly forested area 15 km from his home. Collections were made throughout this area, along the route he followed from the city, and at various sites in the city itself. No Ebola virus was isolated, but a description of the collections and the ecotopes involved is given for comparison with future studies of other outbreaks.

Adult↗

PubMed1999

The process of outcomes management in an acute care facility.

Outcomes reports evaluate the care given to a patient population. The establishment of a system to collect, analyze, and report outcomes is essential because regulatory agencies require that comparisons of outcomes be made externally. The outcomes manager at Mission Hospital Regional Medical Center facilitated a team to evaluate the patient in active labor. The focus was to establish a process of care that would maintain quality of care and decrease the cesarean section rate. Cesarean section rate went from 22 percent to 16 percent. Customer satisfaction scores were elevated and financial outcomes or cost savings were $631,000 in 1998.

Acute Disease↗

PubMed1999

Bone marrow transplantation as effective treatment of central nervous system disease in globoid cell leukodystrophy, metachromatic leukodystrophy, adrenoleukodystrophy, mannosidosis, fucosidosis, aspartylglucosaminuria, Hurler, Maroteaux-Lamy, and Sly syndromes, and Gaucher disease type III.

Over 400 patients with lysosomal and peroxisomal storage diseases have received hematopoietic stem cell transplantation from normal donors. Without treatment, all of these diseases have an inexorable fate leading to central nervous system deterioration and early death. On the other hand, all of the engrafted hosts have had a remarkable positive clinical improvement in response to normalization of previously deficient enzymatic activity. Survival data for those engrafted indicates continued life-span as long as two decades beyond transplantation. The particular diseases treated in this way are included in this article. The specific indications and methods for transplantation are also included in this article.

Bone Marrow Transplantation↗

PubMed1999

Association analysis of exonic variants of the gene encoding the GABAB receptor and alcohol dependence.

The present association study tested whether genetic variation of the GABAB receptor (GABABR1) gene confers vulnerability to alcohol dependence. The genotypes of three DNA sequence variants in exons 1a1, 7 and 11 of the GABABR1 gene were assessed in 234 German controls and 350 German alcohol-dependent subjects, including three more homogeneous subgroups of alcoholics, marked by (1) history of parental alcoholism (n = 121); (2) history of alcohol withdrawal seizure or delirium (n = 108); and (3) comorbidity of dissocial personality disorder (n = 60). The allele frequencies of none of the investigated GABABR1 variants differed significantly between the controls and the groups of alcoholics when a correction for multiple testing was taken into account (P > 0.004). However, trends (P < 0.10) towards an excess of the Ser489 allele of the exon 7 polymorphism were found in the subgroups of alcoholics, and of the common allele of the exon 11 polymorphism in the entire sample of alcoholics (P = 0.032), alcoholics with parental alcoholism (P = 0.084) and the dissocial alcoholics (P = 0.037). Our findings suggest that the investigated GABABR1 variants do not contribute a substantial effect (RR > 3) to the genetic variance of alcohol dependence. Nevertheless, the hints towards potential allelic associations of the exon 7 and 11 polymorphisms with dissocial alcoholism emphasize further studies to test more defined phenotype-genotype relationships.

Adult↗

PubMed1999

Bone marrow transplantation for globoid cell leukodystrophy, adrenoleukodystrophy, metachromatic leukodystrophy, and Hurler syndrome.

Bone marrow transplantation protocols for inherited metabolic storage diseases are unique for each disorder treated. Differences depend also upon how old the patient was when onset occurred and rate of progression of disease. Treatment is directed to prevent or ameliorate the inexorable neurological deterioration that is the major pathophysiological event in all of these inherited metabolic storage diseases.

Adrenoleukodystrophy↗