Detection and Characterization of Lewis Antigens in Plasma of Lewis-Negative Individuals Evidence of Chain Extension as a Result of Reduced Fucosyltransferase Competition

Nonacid plasma glycolipids from Lewis-negative individuals of nonsecretor, partial-secretor and secretor phenotypes were prepared and separated by thin-layer chromatography and immunostained with radiolabelled Lewis antibodies. Lewis-positive plasma and intestinal epithelial cell glycolipids from Caucasians representing the four recognized Lewis and secretor combined phenotypes were used as controls. By presenting these purified total glycolipids in a cell-free environment to Lewis antibodies we were able to demonstrate the presence of small amounts of Lewis antigens in Lewis-negative individuals. It is shown that lactotetraosylceramide and extended precursor glycolipids are present in all Le(a–b–) nonsecretors. Le^awas detected in 1 of the 3 Le(a–b–) nonsecretor plasmas and in the intestinal sample of the same phenotype. Lactotetraosylceramide was absent but H type 1 and Le^bwere both present in all group O Le(a–b–) secretors, and extended H type 1 reactive structures were also found in the partial secretor. These results clearly demonstrate that although the Lewis-negative phenotype exists at the serological level, this phenotype is not an 'all-or-nothing' phenomenon at the chemical level. We also show that in the presence of reduced fucosyltransferase activity, increased elongation of the precursor chain occurs, which allows us to postulate that fucosylation of the precursor prevents or at least markedly reduces chain elongation.     

Body composition in patients treated with peritoneal dialysis

Background: Malnutrition is a common complication in uremia and during maintenance dialysis. Several factors contribute to its development. Different modes of dialysis treatment may differ in their effects on nutritional status. Methods: In order to analyse the nutritional consequences of peritoneal dialysis (PD), body composition analyses were performed in PD patients between February 1993 and March 1996. Body cell mass (BCM) was estimated from measurements of total body potassium (TBK) in a whole-body counter. Total body water (TBW) was determined by measurement of tritiated water. Body fat (BF) was calculated from body weight (BW), TBK and TBW. Observed values were related to predicted (o/p) derived from local population studies. Results: Sixty patients were repeatedly investigated during the study period. Of these, 34 were investigated during the first year of PD. At the start of dialysis, TBK o/p was 0.94 and BF o/p 0.76. No change in body composition was seen during the observation period in the group as a whole. However, within the group individual changes in BW were strongly correlated with individual changes in BF (r=0.66, P=0.0001). Twenty-six patients were examined during the second and third year of PD. In this group, BW o/p remained constant over time. However, there was a small but significant decline of TBK o/p and a concomitant increase of BF o/p (P<0.05). No correlation was observed between changes in TBK and changes in serum albumin. Conclusions: The results of this study indicate, that there may be a risk for further reduction of body cell mass during long-term PD treatment, while body energy stores are maintained or even increased.     

The rheumatic patient''s early needs and expectations

During the last few years, studies have revealed that the need for psychosocial support and concrete social services are great in the early stages of the treatment of rheumatic diseases. The ability to keep a job, to do household chores, to participate in leisure activities and to maintain social relations is clearly impaired. Anxiety and depression are not unusual and often associated with weak support from relatives, loneliness and disturbed family relations. Nevertheless, the patients report resilience and determination to cope with the impacts of illness. Crisis intervention, vocational guidance and counselling about problems concerning the disease should be available and offered to the patients. As the patients seem to be unaccustomed to talking about their psychosocial problems, an empathetic and information-seeking attitude on the part of the health care staff is essential.     

Ramp-function work test suitable for automatic computation

Heart rate (HR) response to step-function and ramp-function (20 W/min) work tests was compared in 12 healthy subjects. For a given power output (P), HR was substantially lower in the ramp tests. The HR difference increased with power output and increasing difference in work time between the test types. The HR difference can be explained in terms of a drift component (which accounts for 1/3 of the difference) and a lag component (2/3). As a consequence of the HR differences, P for a given HR is higher in ramp tests. Work capacity expressed, for example as P170, can be determined in ramp tests, and the result can be translated to step-function P170. The precision in this translation is markedly improved if a steady-state period is incorporated into the ramp test.     

Multicenter quality assessment of PCR methods for detection of enteroviruses

We conducted a multicenter evaluation of commercial and in-house PCR methods for the detection of enteroviruses. Three coded panels of test and control RNA samples, artificial clinical specimens, and representative enterovirus serotypes were used to assess amplification methods, RNA extraction methods, and reactivities with different enterovirus serotypes. Despite several differences between PCR methods, there was good agreement, although some variation in sensitivity was observed. Most PCR methods were able to detect enterovirus RNA derived from 0.01 50% tissue culture infective dose (TCID50) and were able to detect at least 1 TCID50 of enterovirus in cerebrospinal fluid, stool, or throat swab specimens. Most were also able to detect a wide range of enterovirus serotypes, although serotypic identification was not possible. Some laboratories experienced false-positive results due to PCR contamination, which appeared to result mainly from cross-contamination of specimens during RNA extraction. Provided that this problem is overcome, these PCR methods will prove to be a sensitive and rapid alternative to cell culture for the diagnosis of enterovirus infection.     

Ambulation in patients with myelomeningocele: a 12-year follow-up

Factors determining change in ambulatory status were studied over a 12-year observation time in 60 ambulating patients with myelomeningocele. There were 26 female and 34 male subjects with a median age of 22 years (range, 12-54). We used the method of Lindseth to define the neurologic level of the lesion and classified walking ability according to the criteria of Hoffer. The prevalence of spasticity and spine and lower-limb deformities was assessed. Orthopedic and neurosurgical interventions and other medical events were registered, as well as occurrence of pressure sores, musculoskeletal pain, and use of orthoses. There were 19 patients with downward transitions in ambulatory level during the follow-up time. Factors explaining deterioration in these 19 patients included deterioration of the neurologic level of lesion, spasticity, knee and hip flexion contractures, low-back pain, lack of motivation, as well as those of major medical events like stroke, recurrent septicemia, lower limb edema, and invasive surgical interventions.     

Localization and characteristics of transglutaminase in the rabbit and human eye

Transglutaminases (transamidases; endo--gluta-mine: -lysine transferases) are calcium-dependent enzymes, which cross-link proteins by introducing covalent -(-gluta-minyl)lysine pseudopeptide bonds between the molecules. The distribution and characteristics of transglutaminase in both human and rabbit eyes have been studied. Transglutaminase activity was measured with an isotope technique based on the enzyme catalysed incorporation of¹⁴C-putrescine into casein. Electrophoretic characteristics were studied using agarose gel electrophoresis combined with a specific fluorescent activity staining procedure based on the transglutaminase catalysed incorporation of monodansylthiacadaverine into casein.A thrombin-independent enzyme, indistinguishable from the guinea pig liver transglutaminase with regard to electrophoretic mobility, was found in the choroid/pigment epithelium and ciliary body of the human eye while the lens, retina, iris and vitreous humour did not contain detectable amounts. The lens and the choroid/pigment epithelium of the rabbit eye tissues contained high activities while the activity in the extract from the combined ciliary body/iris was low but measurable.     

Ionotropic glutamate receptor expression in human spinal cord during first trimester development

Quantitative receptor autoradiography and immunoblotting were used to study the expression and distribution of AMPA, kainate and NMDA receptors in first trimester human spinal cord obtained from elective abortions ranging from 4 to 11.5 weeks of gestational age. Spinal cord tissue sections were processed for receptor autoradiography with the ligands [3H]AMPA, [3H]kainate and [3H]MK-801 and the optical density was measured separately in a dorsal region (alar plate) and ventral region (basal plate) of the autoradiographs. Binding sites for all three ligands were demonstrated already at 4-5.5 weeks of gestation and increased continuously during the first trimester both in the dorsal and ventral regions. [3H]AMPA binding to both high- and low-affinity sites increased from undetectable levels to about 35 and 400 fmol/mg tissue, respectively, during this period. A temporal difference in the distribution of [3H]AMPA binding sites was observed. The early homogeneous pattern of [3H]AMPA binding in both alar and basal plates had changed to a heterogeneous pattern at 11 weeks of gestation with the highest density of [3H]AMPA binding sites in the superficial layers of the immature dorsal horn. [3H]kainate and [3H]MK-801 binding sites were densely and homogeneously distributed already at 4 weeks, and steadily increased six- and two-fold, respectively, to about 100 fmol/mg tissue at 11.5 weeks of gestation. Immunoreactive bands corresponding to the NMDA receptor subunits NR1, NR2A, NR2B, NR2C and NR2D were demonstrated by immunoblotting at the earliest between 4.5 and 7 weeks and increasing concentrations were seen up to 11 weeks of gestation. These results suggest that AMPA, kainate and NMDA receptors are expressed in the human spinal cord early in embryogenesis.     

Fatal venous thromboembolism associated with different combined oral contraceptives: a study of incidences and potential biases in spontaneous reporting.

BACKGROUND: Fatal venous thromboembolism (VTE) is a rare complication of combined oral contraceptive (COC) treatment. This study aims to determine incidences of fatal VTE in relation to the type of COC and the percentage of cases reported to the Swedish Adverse Drug Reactions Advisory Committee (SADRAC). A further aim is to compare the characteristics of reported and not reported cases. METHODS: This retrospective study is a separate analysis using data from a larger study that included women aged 15-44 years between 1990 and 1999 with VTE coded as the underlying or contributory cause of death in the Swedish Cause of Death Register. COC use within 2 months of the date of symptom onset or death was identified in 28 cases. Sales data were obtained from the National Corporation of Swedish Pharmacies. Reported cases were identified in the SADRAC database. RESULTS: After excluding two cases where the type of COC was unknown, the crude incidences of fatal VTE were 5.1 (95% CI 2.3, 9.6), 8.6 (95% CI 4.3, 15.4) and 9.1 (95% CI 3.3, 19.8) cases per million women per year for levonorgestrel-, desogestrel- and norethisterone-containing COCs, respectively. Age-adjusted incidences were approximately twice as high for desogestrel- and norethisterone-containing COCs compared with levonorgestrel-containing COCs, although differences were not statistically significant. Thirty-six percent of cases were reported. Reporting was positively associated with information in medical records relevant to the VTE diagnosis that the patient was a COC user and was significantly higher in northern Sweden. CONCLUSION: Results from this study support a higher incidence of fatal VTE with desogestrel-containing COCs than with levonorgestrel-containing COCs.