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Biomedical subjects

F Cohen

Publications and source records attributed to F Cohen.

At least 37 records · Page 2Linked to original sources
PubMed1993

Relationship between gastric acid secretion and the rate of recurrent ulcer after parietal cell vagotomy.

OBJECTIVE: This study assessed the effect of gastric secretion on the rate of recurrent ulcer after parietal cell vagotomy for duodenal ulcer. SUMMARY BACKGROUND DATA: Three hundred patients who underwent parietal cell vagotomy for duodenal ulcer between 1975 and 1986 were evaluated. The mean follow-up period for 280 patients was 5 years. METHODS: The gastric secretion tests concerned basal acid output (BAO) and peak acid output stimulated by pentagastrin or insulin. Tests were preoperative for 172 patients and postoperative for 118. RESULTS: At the end of that time, the overall incidence of symptomatic recurrent ulcer was 15%. Two criteria were shown to be important predictors of recurrent ulcer: preoperative BAO > 7 mmol/hr, for which the recurrence rate 5 years after vagotomy was 30% versus 11% for values below this threshold (p = 0.01), and postoperative BAO > 1.4 mmol/hr, for which the recurrence rate at 5 years was 72% versus 8% for lower values (p = 0.0001). All patients with recurrent ulcer had either a postoperative BAO > 7 mmol/hr and/or a postoperative reduction in BAO < 80%. CONCLUSION: Preoperative BAO > 7 mmol/hr and postoperative BAO > 1.4 mmol/hr were shown to be factors predictive of RU. All patients with RU presented either with preoperative BAO > 7 mmol/hr and/or a reduction in BAO < 80%. Consequently, in our opinion, these criteria could be used either to select patients for vagotomy or to assess the effectiveness of vagotomy of different types, especially those performed by celioscopy.

Adult↗
PubMed1993

Immunologic changes occurring at kindergarten entry predict respiratory illnesses after the Loma Prieta earthquake.

Previous studies in adult populations have demonstrated alterations in immune function after psychologically stressful events, and pediatric research has shown significant associations between stress and various childhood morbidities. However, no previous work has examined stress-related immune changes in children and subsequent illness experience. Twenty children were enrolled in a study on immunologic changes after kindergarten entry and their prospective relationship to respiratory illness (RI) experience. Midway through a 12-week RI data collection period, the October 17, 1989 Loma Prieta earthquake occurred. The timing of this event created a natural experiment enabling us to study possible associations between immunologic changes at kindergarten entry, the intensity of earthquake-related stress for children and parents, and changes in RI incidence over the 6 weeks after the earthquake. Immunologic changes were measured using helper (CD4+)-suppressor (CD8+) cell ratios, lymphocyte responses to pokeweed mitogen, and type-specific antibody responses to Pneumovax, in blood sampled 1 week before and 1 week after school entry. RI incidence was assessed using home health diaries and telephone interviews completed every 2 weeks. RIs per child varied from none to six. Six children showed an increase in RI incidence after the earthquake; five experienced a decline. Changes in helper-suppressor cell ratios and pokeweed mitogen response predicted changes in RI incidence in the postearthquake period (r = .43, .46; p < .05). Children showing upregulation of immune parameters at school entry sustained a significant increase in RI incidence after the earthquake.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibody Formation↗
PubMed1992

Predicted alpha-helical regions of the prion protein when synthesized as peptides form amyloid.

By comparing the amino acid sequences of 11 mammalian and 1 avian prion proteins (PrP), structural analyses predicted four alpha-helical regions. Peptides corresponding to these regions of Syrian hamster PrP were synthesized, and, contrary to predictions, three of the four spontaneously formed amyloids as shown by electron microscopy and Congo red staining. By IR spectroscopy, these amyloid peptides exhibited secondary structures composed largely of beta-sheets. The first of the predicted helices is the 14-amino acid peptide corresponding to residues 109-122; this peptide and the overlapping 15-residue sequence 113-127 both form amyloid. The most highly amyloidogenic peptide is AGAAAAGA, which corresponds to Syrian hamster PrP residues 113-120 and is conserved across all species for which the PrP sequence has been determined. Two other predicted alpha-helices corresponding to residues 178-191 and 202-218 form amyloids and exhibit considerable beta-sheet structure when synthesized as peptides. These findings suggest the possibility that the conversion of the cellular isoform of PrP to the scrapie isoform of PrP involves the transition of one or more putative PrP alpha-helices into beta-sheets and that prion diseases are disorders of protein conformation.

Amino Acid Sequence↗
PubMed1992

Staphylococcal infections in childhood dermatomyositis--association with the development of calcinosis, raised IgE concentrations and granulocyte chemotactic defect.

There is a high incidence of staphylococcal infection in children with dermatomyositis, which is limited to those children who either already have or subsequently develop calcinosis. Of 15 children followed up for 3-10 years after diagnosis, all nine who developed calcinosis had infections with Staphylococcus aureus compared with none of six without calcinosis. Of these nine, the occurrence of staphylococcal infections before calcinosis was observed in four, suggested by history in two, and unclear in three children. Granulocyte chemotaxis to Staphylococcus aureus was more severely depressed in those children with calcinosis, whereas those without calcinosis did not differ significantly from controls. The chemotactic defect was due to a serum factor (patients' serum depressed control chemotaxis and control serum corrected the patients' chemotaxis). The nine children with calcinosis also had significantly higher serum IgE concentrations than non-atopic age matched controls; the six without calcinosis did not differ from controls. The increased IgE concentrations appeared to develop after staphylococcal infection and before calcinosis. Two of five patients with calcinosis had increased antistaphylococcal IgE antibodies; neither of the two patients without calcinosis had such increased antibodies. This suggests preceding immunological differences in patients with dermatomyositis who do and do not subsequently develop calcinosis, either increasing susceptibility to Staphylococcus aureus infection or potentially resulting from such infections.

Antibodies, Bacterial↗
PubMed1992

[Paralytic pontine exotropia disclosing endocarditis].

A case of bacterial endocarditis complicated by paralytic pontine exotropia is reported. Magnetic resonance imaging clearly showed a rostral lesion of the paramedial pontine reticular formation and the medial longitudinal fasciculus. The occurrence of paralytic pontine exotropia is suggestive of ischaemia, and patients with this so-called "one-and-a-half syndrome" associated with signs of infection should be investigated for endocarditis.

Brain Ischemia↗
PubMed1991

Focal scleroderma and severe cardiomyopathy. Patient report and brief review.

A 21-month-old infant presented with simultaneous localized scleroderma and severe cardiomyopathy with heart failure. Cardiac abnormalities and serological changes (positive rheumatoid factor assay, elevated IgM and IgG levels, and elevated erythrocyte sedimentation rate) reverted to normal with prednisone therapy, and there was substantial, though incomplete, resolution of her skin changes during the same period. To our knowledge, this is the first patient with definite, clinically significant cardiac involvement associated with focal scleroderma. The possibility of internal organ involvement, including cardiac involvement, must be considered with focal scleroderma as well as with progressive systemic sclerosis.

Cardiomyopathy, Dilated↗
PubMed1989

Depletion of CD8+ cells in human thymic medulla results in selective immune deficiency.

CD8 molecules expressed on the surface of a subset of T cells participate in the selection of class I MHC antigen-restricted T cells in the thymus, and in MHC-restricted immune responses of mature class I MHC antigen-restricted T cells. Here we describe an immune-deficient patient with lack of CD8+ peripheral blood cells. The patient presented with Pneumocystis carinii pneumonia and was unable to reject an allogeneic skin graft, but had normal primary and secondary antibody responses. Examination of the patient's thymus revealed that the loss of CD8+ cells occurred during intrathymic differentiation: the patient's immature cortical thymocytes included both CD4+ and CD8+ cells while the mature medullary cells expressed the CD4 but not the CD8 protein on their surface. Northern blot and polymerase chain reaction analyses revealed the presence of CD8 alpha and beta mRNA in the patient's thymus but not in the peripheral blood. Both class I MHC antigen expression and the expressed TCR V beta repertoire are normal in this patient. These data are consistent with an impaired selection of CD8+ cells in the patient's thymus and support the role of the CD8 surface protein in thymic selection previously characterized in genetically manipulated and inbred mice.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1989

Effect of personal pain experience on pain assessment.

The purpose of this study was to determine the effect of nurses' personal pain experiences on the assessment of their patients' pain. The sample consisted of 134 registered nurses employed in three Midwestern hospitals. In response to a personal pain history questionnaire, pain with headache, menstrual distress and dental events were cited most frequently. Most also reported that a family member had experienced pain in their presence (cancer, surgery, orthopedic injuries). Responses to the Standard Measure of Inferences of Suffering (Davitz & Davitz, 1981) showed significant differences between intensity of pain experienced by the nurse and overall perceived patient psychological distress. Furthermore, the intensity of pain experienced by the nurse was the only variable that predicted significantly perceptions of patients' physical suffering and psychological distress. While additional study is warranted, the findings support the notion that nurses who have experienced intense pain are more sympathetic to the patient in pain.

Attitude of Health Personnel↗
PubMed1989

[The interview in dental clinical examination: the role of reformulation].

Faced to the major role of the patients examination as a part of our interventions in dentistry, and with to our pedagogic mission towards students, we propose a method of interviewing the patients based on the principle of reformulation, basic technique in the help-talk. The described experimentation demonstrates the interest of method compared with the classical "interrogatory", particularly with rebellious or "problematic" patients. The personalized interview is efficient in obtaining their cooperation which is a key factor for the subsequent treatment.

Adult↗
PubMed1989

[Guided teaching with the Philips 6/6 method].

Complementary to the didactic lecture, the guided teaching system enables the students to formulate and resolve one or more problematic cases specific to the topic. The application of the PHILIPS 6/6 inter-active non-directive method, allowed us through the teaching of a simple subject (the rubber dam in restorative dentistry) to emphasize the multiple performances of group dynamics as applied to dental education.

Dentistry, Operative↗
PubMed1988

[The course of acquired C 1 esterase inhibitor deficiency in lymphoproliferative syndrome].

Acquired deficiency in C1 esterase inhibitor (C1 INH) was first described by Caldwell in 1972. Since that date, about 30 cases have been reported, in most cases during proliferative lymphocyte B syndromes. The acquired C1 INH deficiency can provoke episodes of angioneurotic edema as in hereditary AE. The complement profile differs, notably by the usual sudden fall in C1. Documented data suggest consumption of complement and therefore of C1 INH. The present case is the first reported of an acquired C1 INH deficiency during a cold hemagglutinin disease. The activation of complement by the classical pathway appears provoked by tumoral cells rather than a humoral factor, as suggested by the efficacy of anti-tumoral therapy in contrast to plasmapheresis in the present case. A possible mechanism for the C1 INH deficiency is discussed.

Anemia, Hemolytic, Autoimmune↗
PubMed1983

Prostanoid synthesis by cultured gastric and duodenal mucosa: Possible role in the pathogenesis of duodenal ulcer.

Cultured duodenal mucosa obtained from normal subjects synthesized and secreted significantly less prostaglandin E2 (PGE2), 6-keto-PGF1 alpha, and thromboxane B2 (TXB2) than cultured gastric mucosa obtained from the same subjects. Accumulation of PGE2, 6-keto-PGF1 alpha, and TXB2--the stable metabolites of prostacyclin I2 and thromboxane A2, respectively--by cultured gastric mucosa obtained from 21 untreated patients with active duodenal ulcer was significantly lower than their respective accumulation by cultured gastric mucosa obtained from 14 normal subjects. Accumulation of all three prostanoids by cultured duodenal mucosa obtained from patients with active duodenal ulcer and from normal subjects was not significantly different. PGE2, 6-keto-PGF1 alpha, and TXB2 accumulation was five to six times higher than their respective content in fresh tissue before culture and was inhibited by flufenamic acid. These results suggest that a decrease in endogenous gastric prostanoid synthesis may have a role in the pathogenesis of peptic ulcer disease.

6-Ketoprostaglandin F1 alpha↗