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P Peterson

Publications and source records attributed to P Peterson.

At least 19 recordsLinked to original sources
PubMed1997

Steroid 21-hydroxylase autoantibodies in insulin-dependent diabetes mellitus. Childhood Diabetes in Finland (DiMe) Study Group.

We have studied the sera from 304 patients with insulin-dependent diabetes mellitus (IDDM) for steroid 21-hydroxylase (P450c21) autoantibodies by an in vitro translation and immunoprecipitation assay. Autoantibodies to P450c21 were found in 7 patients with IDDM (2.3%). When the IDDM patients with P450c21 antibodies were analyzed for their HLA, 6 of them (86%) belonged to the HLA DQB1*0201-positive group. A strong correlation (r = 0.91, P < 0.001) of immunoprecipitation results was observed with adrenocortical autoantibodies detected by indirect immunofluorescence, indicating that the adrenal autoantibodies in patients with IDDM were anti-P450c21 autoantibodies. The levels of P450c21 autoantibodies were significantly higher (P < 0.05) in patients with IDDM than in 13 (9 P450c21 autoantibody positive) patients with Addison's disease. Although the occurrence of P450c21 antibodies in IDDM was relatively low, antibody-positive patients had high antibody levels and may have an ongoing subclinical process of adrenal autoimmunity.

Addison Disease↗
PubMed1997

Identification of Her-2/Neu CTL epitopes using double transgenic mice expressing HLA-A2.1 and human CD.8.

The Her-2/neu protooncogene is associated with malignant transformation and aggressive disease. Because of its overexpression in tumor cells and because it has been shown to be immunogenic, this protein represents an excellent target for T-cell immunotherapy. By identifying potential HLA-A2.1-binding peptides from the Her-2/neu sequence, peptides were selected as candidate T-cell epitopes. The immunogenicity of each peptide was evaluated by priming double transgenic mice expressing both the human (hu) CD8 and HLA-A2.1 molecules with synthetic peptides corresponding to these sequences. Because of the lack of interaction between murine CD8 and HLA-A2.1, expression of huCD8 on murine cells facilitates recognition of HLA molecules on human tumor cell lines. This led to the identification of two peptides that elicit an A2-restricted CTL response, one of which has not been previously identified. Both peptide-specific CTL populations were able to specifically lyse A2.1 and Her-2/neu expressing human tumor cells originating from a variety of tissues, demonstrating the utility of this murine model in identifying peptides presented by human cells. However, several Her-2/neu peptides previously reported to be immunogenic for human CTL were found not to be immunogenic in transgenic mice. The basis for these discrepancies is discussed.

Amino Acid Sequence↗
PubMed1997

Immunoprecipitation of steroidogenic enzyme autoantigens with autoimmune polyglandular syndrome type I (APS I) sera; further evidence for independent humoral immunity to P450c17 and P450c21.

Three steroidogenic P450 cytochromes, steroid 17alpha-hydroxylase (P450c17), steroid 21-hydroxylase (P450c21) and side-chain cleavage enzyme (P450scc), have been described as autoantigens in APS I. In this study we report an immunoprecipitation assay for the detection of autoantibodies to these three enzymes using in vitro 35S-labelled antigens. Overall, 33 out of 46 (72%) patients with APS I had autoantibodies to at least one of the three proteins and each protein was recognized by patient sera with equal frequency. A higher rate of autoantibody positivity was observed in APS I patients with Addison's disease compared with patients without Addison's disease (85% versus 39%). All 11 patients with ovarian failure had anti-P450c17 or anti-P450scc antibodies. The immunoprecipitation results with P450c17, P450c21 and P450scc correlated well with the results obtained by immunoblotting assays. In addition, the steroidogenic enzymes 11beta-hydroxylase (P450c11beta), aromatase (P450arom), 3beta-hydroxysteroid dehydrogenase (3betaHSD) and adrenodoxin were studied by immunoprecipitation assay, but no reaction was found either with 46 APS I or with 26 healthy control sera. To study the suggested immunological cross-reactivity between P450c17 and P450c21 enzymes, nine APS I patient sera were preabsorbed with bacterially expressed P450c17 or P450c21 and subsequently used in immunoprecipitation assay. The absorption experiments clearly indicated that the preincubation inhibited only the reactivity of corresponding antigen, suggesting independent autoantibody response to the two enzymes. Our results suggest that the immune response to some but not to all steroidogenic enzymes is a specific feature of APS I that may be pathogenically significant.

Absorption↗
PubMed1997

Experience of the Polycythemia Vera Study Group with essential thrombocythemia: a final report on diagnostic criteria, survival, and leukemic transition by treatment.

This report suggests modest changes in the criteria used for the diagnosis of ET and allows tentative recommendations concerning therapy. As outlined in Table I, we believe that absent stainable marrow iron does not necessarily indicate iron deficiency in these patients and that the serum ferritin and RBC mean corpuscular volume should be incorporated in this assessment. Normal values speak strongly against iron-deficient erythropoiesis. A search for the bcr/abl gene rearrangement should be included with the marrow karyotype to exclude CML. Finally, cytogenetic data and morphologic study of the marrow should be used to be certain that a MDS should not be considered. It may be that measurements of serum thrombopoietin levels may be useful in the future. Nonetheless, in principle, ET remains a diagnosis of exclusion as we have originally suggested. For therapy, HU remains an excellent choice for the older patient at risk for thrombosis. Nonetheless, no myelosuppressive therapy remains a perfectly viable option, particularly for the young patient and the older with low thrombotic risk. The roles of anagrelide and alpha interferon in this setting have not been fully defined. Experience with both has still been relatively short. It would be ideal if prospective, randomized trials could be mounted to address these questions. We conclude with confidence that return to older approaches such as 32P and AA in patients who fail on HU is to be discouraged. The use of anagrelide or interferon alfa seems to be a much more appropriate approach. We have not investigated the role of antithrombotic agents such as aspirin in ET. In PV, the combination of aspirin, 300 mg three times daily, and dipyridamole, 75 mg three times daily, failed to reduce the rate of thrombosis and was associated with an increased rate of hemorrhage. It is rational to suggest that lower doses of aspirin (ie, < 325 mg daily) might be associated with less hemorrhage and, perhaps, a beneficial effect on thrombosis. This remains to be shown.

Humans↗
PubMed1996

Chromosome 18 translocation (18;21) (p11.1;p11.1) associated with psychosis in one family.

In the course of recruiting families with 2 schizophrenic siblings for genome screening and linkage studies, a family was found with mental retardation, schizophrenia, and/or other related psychotic illnesses in individuals who also had an unbalanced or balanced translocation between chromosomes 21-18 [t(18;21)(p11.1;p11.1)]. The pericentric region of chromosome 18 has already been noted as a possible location of a gene for bipolar psychosis. The family described here provides further evidence that this region should be examined for a candidate psychosis gene.

Adult↗
PubMed1996

Intraoperative autologous blood donation preserves red cell mass but does not decrease postoperative bleeding.

BACKGROUND: Postoperative bleeding and transfusion remain a source of morbidity and cost after open heart operations. The benefit of the acute removal and reinfusion of fresh autologous blood around the time of cardiopulmonary bypass-a technique known as intraoperative autologous donation (IAD)-has not been universally accepted. We sought to more clearly evaluate the effects of IAD on allogeneic transfusion and postoperative bleeding by removing, preserving, and reinfusing a calculated maximum volume of fresh autologous whole blood. METHODS: Ninety patients undergoing coronary artery bypass grafting or valvular operations were prospectively randomized to either have (IAD group) or not have (control group) calculated maximum volume IAD performed. Treatment was otherwise identical. Transfusion guidelines were uniformly applied to all patients. RESULTS: An average volume of 1,540 +/- 302 mL of fresh autologous blood was removed and reinfused in the IAD group. Postoperative hematocrits were significantly greater at 12 and 24 hours postoperatively in the IAD group versus the control group despite a significant decrease in both the percentage of patients in whom allogeneic red blood cells were transfused (17% versus 52%; p < 0.01) and the number of red blood cell units transfused per patient per group (0.28 +/- 0.66 and 1.14 +/- 1.19 units; p < 0.01). Conversely, chest tube output, incidence of excessive postoperative bleeding, postoperative prothrombin time, and platelet and coagulation factor transfusion requirement did not differ between groups. CONCLUSIONS: These results indicate that intraoperative autologous donation serves to preserve red blood cell mass. Its routine use in eligible patients is therefore justified. However, the removal and reinfusion of an individually calculated maximum volume of fresh autologous blood had no effect on postoperative bleeding or platelet and coagulation factor transfusion requirement. This lack of hemostatic effect belies the beliefs of many about the primary action of IAD, helps to delineate the optimal way in which to perform IAD, and carries implications regarding the use of allogeneic platelet and coagulation factors for the treatment of early postoperative bleeding.

Adult↗
PubMed1996

Detection of candidal antigens in autoimmune polyglandular syndrome type I.

Autoimmune polyglandular syndrome type I (APS I) is associated with chronic mucocutaneous candidiasis. To characterize the antibody responses in this subgroup of Candida albicans infections, we screened a candidal cDNA expression library with patient sera and found four cDNA clones encoding the immunopositive proteins enolase, heat shock protein 90, pyruvate kinase, and alcohol dehydrogenase. The reactivity to these antigens was studied further by immunoprecipitation assays with in vitro-transcribed and -translated proteins. Analysis of sera from 44 APS I patients showed that the highest antibody reactivity was found with enolase (80% of patients reactive), but significant serological responses were also found with heat shock protein 90 (67%), pyruvate kinase (62.5%), and alcohol dehydrogenase (64%). Overall, 95.5% of patients had detectable antibodies to at least one of these proteins. The cDNAs of enolase and heat shock protein 90 were also expressed in Escherichia coli and studied by immunoblotting. Again, 84% of sera reacted with enolase, whereas 44% of sera reacted with heat shock protein 90. A good correlation between the two methods was found for both enolase (r = 0.86; n = 58; P < 0.001) and heat shock protein 90 (r = 0.71; n = 56; P < 0.001). Our results indicate that the four abundant candidal proteins are the major antigens and can be used as accurate markers of candidiasis in APS I patients. The immunoprecipitation assay described here is particularly useful for the rapid analysis of a large number of samples.

Antigens, Fungal↗
PubMed1995

Putative receptor binding sites on alphaviruses as visualized by cryoelectron microscopy.

The structures of Sindbis virus and Ross River virus complexed with Fab fragments from monoclonal antibodies have been determined from cryoelectron micrographs. Both antibodies chosen for this study bind to regions of the virions that have been implicated in cell-receptor recognition and recognize epitopes on the E2 glycoprotein. The two structures show that the Fab fragments bind to the outermost tip of the trimeric envelope spike protein. Hence, the same region of both the Sindbis virus and Ross River virus envelope spike is composed of E2 and is involved in recognition of the cellular receptor.

Antibodies, Monoclonal↗
PubMed1995

Patterns of neuropsychological functioning among patients with multi-infarct and Alzheimer's dementia: a comparative analysis.

Cognitive and neuropsychological tests are often employed to help describe the functioning of patients with multi-infarct dementia (MID) or patients with dementia of the Alzheimer's type (DAT). In this study, the Halstead-Reitan Neuropsychological Battery (HRNB), Wechsler Adult Intelligence Scale-Revised (WAIS-R), and Wechsler Memory Scale (WMS) were completed by 20 MID patients and 62 patients with DAT. Total scores on these measures did not differentiate DAT and MID patients. Contrary to clinical observations, cognitive tasks assessing social judgment did not differentiate between the groups. However, MID patients demonstrated greater variability in test scores. Compared with DAT patients, the MID patients demonstrated better preserved memory as shown on the WMS in comparison to the WAIS-R IQ.

Aged↗
PubMed1995

Expectations and sequelae to hypnosis: initial findings.

As part of the introduction to an experiment using the Harvard Group Scale, subjects were given one of three brief instructions before being hypnotized: (1) no mention of negative or positive aftereffects, (2) vague warning of negative aftereffects, i.e., "some mildly unpleasant experiences", plus, "most persons report their experiences to be pleasurable and interesting", (3) specific warning of negative aftereffects, i.e., "approximately one half subjects have reported mild, short-term aftereffects such as headache", etc. (no positive information). The "specifically warned" Ss showed more negative aftereffects than both of the other groups, and the "no mention" Ss showed more than the "vaguely warned" Ss. The positive suggestions in the "vaguely warned" Ss instructions may have confounded the expectation for negative effects. A follow up study used instructions varying only in the degree of expectations for negative aftereffects (no mention of positive aftereffects). The results did not show group differences in negative aftereffects as predicted, however, correlational results suggested some interesting interactions among subject variables and the type of prehypnotic instructions administered.

Humans↗
PubMed1995

Clinicians and pathologists in the management of breast disease. An evolving relationship.

The breast is host to a spectrum of benign and malignant diseases. Medical advances during the last few decades have changed and refined the diagnosis of breast diseases considerably, and their treatment has become increasingly sophisticated. These changes have changed the relationship between pathologists and clinicians: Close collaboration has become even more essential for optimal patient care.

Adult↗
PubMed1994

[N-methylnorleucine-(28,31)]cholecystokinin-(26-33) (SNF 8702) activity at a cloned rat CCKB receptor.

[N-methyl-Nle 28,31)]cholecystokinin-(26-33) (SNF 8702) is a highly selective ligand for the CCKB type of receptor present in the vertebrate central nervous system. Radioligand binding data showing that SNF 8702 binding affinity is reduced by the GTP analog guanylyl-imidodiphosphate suggest that SNF 8702 is an agonist but the ability of SNF 8702 to activate CCKB receptors has not been demonstrated. The present study shows that SNF 8702 is a highly potent agonist at rat CCKB receptors expressed on COS-7 cells and that these receptors are coupled to the mobilization of intracellular calcium. The A50 measured for SNF 8702-induced calcium mobilization (66 pM) is over 6-fold less than that of cholecytstokinin octapeptide (420 pM). Data are also presented showing that SNF 8702 has high binding affinity for these receptors with a Kd value (760 pM) consistent with previous measurements using guinea pig brain tissue preparations.

Animals↗