The educational sequelae of a randomized prospective study

Five hundred and thirty surgeons were contacted using a blinded questionnaire to determine the educational sequelae of a randomized prospective study. The participants were chosen randomly to represent three distinct variables: (1) those involved with the original study, (2) those who heard the study results presented, and (3) surgeons who would be interested in the subject (colon trauma) but without controlled exposure or participation. While response varied, it was clear that behavior modification was most affected by involvement with a randomized study as a participant. Source recognition, despite evidence of changes in practice patterns, was low among nonparticipants, suggesting that the dissemination of study results occurs without conscious effort or remembrance of procedural methodology.     

Autoantibodies to oxidised low density lipoproteins in IDDM are inversely related to metabolic control and microvascular complications

Summary Diabetes mellitus is associated with an increased risk of atherosclerosis. The oxidation of low-density lipoproteins (LDL) is considered a key event in the initiation of atherosclerosis. To investigate LDL oxidation in vivo we measured autoantibodies to oxidised LDL (oxLDL) in 94 patients with insulin-dependent diabetes mellitus (IDDM), compared to 27 age-matched, healthy control subjects. Patients and control subjects were screened for autoantibodies using a solid phase ELISA, comparing the binding to oxLDL with that to native LDL (nLDL). In patients with IDDM the oxLDL/nLDL antibody ratio was significantly higher than in control subjects (means ± SEM: 2.24 ± 0.26 vs 1.17 ± 0.17, p < 0.03). Antibody-negative patients had a longer diabetes duration (13.5 ± 1.3 vs 9.1 ± 1.1 years, p < 0.01) and higher actual and mean HbA_{1 c} levels compared to antibody-positive patients (8.8 ± 0.2 vs 7.9 ± 0.2 %, p < 0.005 and 8.3 ± 0.2 vs 7.7 ± 0.2 %, p < 0.03; respectively). In patients with a high microangiopathy score, the antibody ratio was lower than in patients without complications (1.04 ± 0.10 vs 2.40 ± 0.29, p < 0.01). OxLDL specific immune complexes were found exclusively in antibody-negative as compared to antibody-positive patients (18.3 vs 0 %; p < 0.01). Our data demonstrate an inverse relationship between free oxLDL antibodies and the severity of the disease. This apparent paradox can be explained in part by our demonstration of oxLDL immune complexes, masking free antibodies. [Diabetologia (1998) 41: 350–356] Received: 18 June 1997 and in final revised form: 30 September 1997     

Age dependence of vascular prostacyclin formation in man (author's transl)

The synthesis of prostacyclin (PGI2), the most potent known inhibitor of platelet aggregation, varies with age. After 30 years the production decreases, but increases again in the 6th and 7th decade. Contrary to these physiological variations patients suffering from juvenile onset diabetes or peripheral angiopathy show a markedly decreased prostacyclin synthesis. Since the prostacyclin system in thought to be an important blood vessel protector, the pathological low level of PGI2-synthesis could be a key position in development or progression of vascular complications.     

Early opacification of silicone intraocular lenses: Laboratory analyses of 6 explants

PURPOSE: To report laboratory analyses of 6 intraocular lenses (IOLs) explanted from patients who had visual disturbances caused by early postoperative opacification of the lens optic. SETTING: John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. METHODS: Six patients with 3-piece silicone lenses presented with optic cloudiness as early as a few hours after implantation. The lenses were implanted in 4 locations in Brazil and in France. The lenses in Brazil were stored at the same location before implantation. Gross and microscopic analyses were performed (dry and hydrated states). One half of each specimen underwent gas chromatography/mass spectrometry (GC/MS) analysis and/or extraction by isopropyl alcohol or acetonitrile. One lens also underwent scanning electron microscopy (SEM) with energy dispersive x-ray spectroscopy (EDS). The IOLs were examined for the presence of contaminants or deposits that could cause fast optic opacification. RESULTS: The IOLs showed a white optic discoloration in the hydrated state but became transparent on complete dehydration. Suspect exogenous chemical compounds were identified in GC/MS analyses; general classes included terpenes and ketones, typically found in industrial cleaning agents and fumigants. Surface analysis (SEM and EDS) did not show any significant deposits on the external surfaces and sagittal cut in 1 of the specimens. CONCLUSIONS: Most IOLs are enclosed in semipermeable packages to allow sterilization by ethylene oxide gas. During cleaning or disinfection of storage rooms, aerosolized solutions may introduce chemicals through the package and onto the IOLs. This may cause surface changes in the IOL, promoting opacification by water ingress in the aqueous environment. Cleaning and disinfection procedures of IOL storage areas should be monitored carefully.     

Antitumoral activity of interferon-gamma involved in impaired immune function in cancer patients

Insufficient immunosurveillance is an important aspect in early tumorigenesis and in the pathogenesis of malignant disease. In the later course of cancer, the development of immunodeficiency is considered the major reason for disease progression and death. Within the anti-tumoral host defense reaction, Th1-type cytokine interferon-gamma (IFN-gamma) is of particular relevance. IFN-gamma stimulates several anti-proliferative and thus tumoricidal biochemical pathways in macrophages and other cells and also in tumor cell lines. These include inducible nitric oxide synthase, indoleamine (2, 3)-dioxygenase, an enzyme degrading the essential amino acid tryptophan, and the production of reactive oxygen species and neopterin in human macrophages and dendritic cells. Although the anti-proliferative strategy of the immune system aims to inhibit the growth of malignant cells, it can also affect T-cell response and thus contribute to the development of immunodeficiency. Accelerated degradation of tryptophan and increased production of neopterin were found to parallel the course of malignant diseases. Moreover, a higher degree of these metabolic changes characterizes poor prognosis and is associated with the development of anemia, weight loss and depressive mood in patients. Available data suggest that immunodeficiency in cancer patients may develop as a long-term side-effect of the antiproliferative and pro-apoptotic mechanisms elicited within Th1-type immune response, and enhanced production of pro-inflammatory cytokine IFN-gamma seems to be critically involved.     

Humoral immunodeficiency to bacterial antigens in patients with juvenile onset diabetes mellitus

Summary Humoral immunity to bacterial antigens was tested in 49 tissue typed patients with juvenile onset diabetes mellitus (JOD) and in 50 healthy controls. The number of patients with agglutinins to E. coli and staphyloccoci was significantly lower compared to controls (p<0.001, p<0.01 respectively). Missing antibody formation to pertussis and diphtheria toxoid could also be detected in a higher percentage of JOD patients than of controls (p < 0.05; p 0.05, respectively). By contrast heteroagglutinins to sheep and rabbit erythrocytes were found in similiar proportion in both groups and the values of immunoglobulin serum concentrations showed no difference between patients and controls. In addition no correlation between antibody formation and genes of the HLA complex was found. It is suggested that the severely reduced agglutinin formation to bacterial antigens might be partly responsible for susceptibility to bacterial infections in juvenile diabetics.National Blood Group Reference Laboratory (WHO), National Tissue Typing Reference Laboratory (Council of Europe).     

Seropositive rheumatoid arthritis associated with decreased diffusion capacity of the lung.

Sixty-two patients with classical or definite rheumatoid arthritis were subjected to lung function analysis. The various parameters--spirography, plethysmography, blood gas analysis, measurement of lung compliance, and diffusion capacity--were correlated with duration and stage of disease, and with rheumatoid factor titres. A statistically significant correlation was found to exist between Rose-Waaler titre and specific diffusion capacity. Similar results between Rose-Waaler titre and lung compliance, however, were not statistically significant.     

Assessment of GH reserve before and after successful treatment of adult patients with Cushing's syndrome

OBJECTIVE: Several studies have demonstrated impaired GH secretion in patients with active Cushing's syndrome (CS). It has been suggested that persistence of GH deficiency, despite treatment of cortisol excess, may delay the recovery of these patients and therefore temporary treatment with GH may have some benefit. However, the time course of restoration of GH secretion after successful treatment of CS has only been investigated in a limited number of mostly paediatric reports. The aim of the present study was the evaluation of GH reserve in adult patients with CS before and after correction of cortisol excess. DESIGN AND PATIENTS: Sixteen patients (12 females, four males) with CS aged 44.7 +/- 5.05 years were recruited. These included seven patients with Cushing's disease, four patients with ectopic ACTH secretion and five patients with adrenal adenoma. All patients were evaluated before any therapeutic intervention. Twelve patients were successfully treated following appropriate surgery and these were further studied. The combined pyridostigmine/GHRH test was used to assess GH reserve in these patients. In a proportion of cases an insulin tolerance test (ITT) was also used. RESULTS: Before any therapeutic intervention, an impaired GH response to PD/GHRH was noted in all patients. Restoration of GH response at 6 months was observed in six patients (50%); at 12 months in two; at 18 months in one patient. Two of the patients with no restoration of GH response at 12 months did not accept further investigation. Only one patient did not achieve an adequate GH response even when tested 30 months following cure of CS. Restoration of GH reserve was more commonly observed in those patients in whom there was recovery of the HPA axis. There was a good correlation between peak GH levels to PD + GHRH and ITT. No statistically significant difference was revealed in IGF-I levels between pre- and post-treatment evaluation. CONCLUSIONS: Adult patients with active Cushing's syndrome demonstrate a profound suppression of stimulated GH secretion. In the majority of these patients the disruption of GH secretion is normalized within a year after successful treatment of endogenous cortisol excess.