Increase in soluble CD95L during subacute phases after human spinal cord injury: a potential therapeutic target.

STUDY DESIGN: A pilot study measuring the levels of serum-soluble CD95 ligand (CD95L) in eight spinal cord-injured patients. OBJECTIVES: To determine the soluble concentration of CD95L in spinal cord injury (SCI) patients after trauma. METHODS: We collected blood samples from eight patients with acute traumatic SCI. Soluble CD95L serum levels were determined using an enzyme-linked immunosorbent assay. American Spinal Injury Association (ASIA) was determined according to ASIA classification. The patients were monitored, and venous blood was drawn after arrival at the hospital on the 1st and 3rd day and during the 1st, 2nd, 4th, 8th and 12th weeks after trauma. RESULTS: The average patient age was 48.1 years (18-86 years). Three patients were paraplegic (two incomplete, one complete), five were quadriplegic (one complete, four incomplete). The serum concentration of soluble CD95L (sCD95L) decreased during the 1st week (41 ng(- l)) and increased after the 2nd week in all eight patients. It peaked during the 4th week (68.5 ng (- l)) and reached a plateau during the 12th week (76.2 ng (- l)). There are many possible explanations for not being able to detect a statistical significance, one of course being the small sample size. CONCLUSION: Promising results for anti-CD95L therapy have already been documented in lab studies with rodents. Anti-CD95L blocks the pro-apoptotic and proinflammatory activity of membrane-bound CD95L during the acute phase of SCI. We observed that sCD95L levels are elevated during the subacute and intermediate phases of SCI. It would be of great interest to study a larger group of patients to determine whether higher sCD95 levels are correlated with improved or impaired neurological outcome or with increasing levels of autoimmune components in peripheral blood.

The effects of bed-rest and countermeasure exercise on the endocrine system in male adults: evidence for immobilization-induced reduction in sex hormone-binding globulin levels.

BACKGROUND AND AIM: There is limited data on the effects of inactivity (prolonged bed-rest) on parameters of endocrine and metabolic function; we therefore aimed to examine changes in these systems during and after prolonged (56- day) bed-rest in male adults. SUBJECTS AND METHODS: Twenty healthy male subjects underwent 8 weeks of strict bed-rest and 12 months of follow-up as part of the Berlin Bed Rest Study. Subjects were randomized to an inactive group or a group that performed resistive vibration exercise (RVE) during bed-rest. All outcome parameters were measured before, during and after bed-rest. These included body composition (by whole body dual X-ray absorptiometry), SHBG, testosterone (T), estradiol (E2), PRL, cortisol (C), TSH and free T3 (FT3). RESULTS: Serum SHBG levels decreased in inactive subjects but remained unchanged in the RVE group (p<0.001). Serum T concentrations increased during the first 3 weeks of bed-rest in both groups (p<0.0001), while E2 levels sharply rose with re-mobilization (p<0.0001). Serum PRL decreased in the control group but increased in the RVE group (p=0.021). C levels did not change over time (p≥0.10). TSH increased whilst FT3 decreased during bed-rest (p all ≤0.0013). CONCLUSIONS: Prolonged bed-rest has significant effects on parameters of endocrine and metabolic function, some of which are related to, or counteracted by physical activity.

Are commonly recommended dosages for vitamin D supplementation too low? Vitamin D status and effects of supplementation on serum 25-hydroxyvitamin D levels--an observational study during clinical practice conditions.

UNLABELLED: Vitamin D deficiency is associated with increased fracture risk. The observational study aimed to investigate vitamin D status and supplementation in ambulatory patients. Only 20% of patients had optimal serum 25-hydroxyvitamin D [25(OH)D] levels. Commonly recommended dosages were insufficient to achieve clinically relevant increase of 25(OH)D levels. Higher dosages were safe and effective under clinical practice conditions. INTRODUCTION: Vitamin D deficiency is associated with adverse health outcome. The study aimed to investigate vitamin D status and supplementation in ambulatory patients. METHODS: Nine hundred seventy-five women and 188 men were evaluated for bone status from January 2008 to August 2008 within an observational study; 104 patients (n = 70 osteoporosis) received follow-up after 3 months. Dosage of vitamin D supplementation was documented and serum 25(OH)D and parathyroid hormone (PTH) determined. RESULTS: In all patients (age, 60.4 ± 14.1 years), distribution of 25(OH)D was 56.3 ± 22.3 nmol/L (normal range, 52-182 nmol/L) and PTH 53.8 ± 67.5 ng/L (normal range, 11-43 ng/L). The proportion of patients with 25(OH)D < 25, 25 to <50, 50 to <75, ≥75 nmol/L was 7.5%, 33.3%, 38.9% and 20.2% in the total group and 20.1%, 38.5%, 30.8%, 10.6% at baseline in the follow-up group, respectively. After 3 months, 3.9% had still 25(OH)D < 25 nmol/L; only 12.5% achieved 25(OH)D ≥ 75 nmol/L. In osteoporosis patients, 25(OH)D increased more in those taking ≥1,500 (median, 3,000) IU vitamin D per day (33.1 ± 14.7 nmol/L) compared with ≤1,000 (median, 800) IU/day (10.6 ± 20.0 nmol/L) (p < 0.0008). PTH decreased more in patients taking ≥1,500 IU/day (-13.2 ± 15.2 ng/L) compared with ≤1,000 IU/day (-7.6 ± 19.2 ng/L; p = 0.29). 25(OH)D was negatively correlated to PTH (r = -0.49, p < 0.0001). An increase of 25(OH)D ≥ 75 nmol/L resulted in normalised PTH. CONCLUSION: Supplementation with higher vitamin D dosages (2,000-3,000 IU/day) is required to achieve a relevant increase of 25(OH)D and normalisation of PTH.

Additive impact of alfacalcidol on bone mineral density and bone strength in alendronate treated postmenopausal women with reduced bone mass.

OBJECTIVES: Assessment of additive impact of alfacalcidol 1 µg daily (Alfa) on bone mineral density (BMD) and on bone strength in postmenopausal women treated with alendronate 70 mg weekly + 500 mg calcium daily. SUBJECTS AND METHODS: In a randomized, double-blind, placebo controlled study, 279 postmenopausal women with osteoporosis or osteopenia participated (intention to treat analysis [ITT]; aged 73.6∓4.7 years) and were treated with 70 mg alendronate (ALN) weekly and 500 mg calcium daily for 36 months. In addition, these patients received either 1 µg alfacalcidol (Alfa) or placebo (PLC) daily. BMD was measured with Dual-Energy-X-ray-Absorptiometry (DXA) at the lumbar spine and proximal femur and at forearm and tibia with peripheral quantitative computed tomography (pQCT) at regular intervals for 36 months. RESULTS: DXA-BMD of lumbar spine (L1-4) increased after 36 months, by 6.65% (p<0.0001) in the Alfa/ALN group versus 4.17% (p<0.0001) in the PLC/ALN group. Group difference was significant after 3 years (p=0.026). At the end of the study, significant differences were found in favor of the Alfa/ALN group in trabecular density (tibia) (p=0.002), cortical density (midshaft tibia) (p=0.043), and bone strength (p=0.001). The remaining parameters showed no differences between the treatment arms, apart cortical bone density at midshaft radius. CONCLUSIONS: Alfacalcidol significantly increases the efficacy of alendronate treatment in osteopenic/osteoporotic postmenopausal women on spinal DXA-BMD, cortical and trabecular BMD of the tibia and also bending stiffness of the tibia.

Resistive vibration exercise attenuates bone and muscle atrophy in 56 days of bed rest: biochemical markers of bone metabolism.

UNLABELLED: During and after prolonged bed rest, changes in bone metabolic markers occur within 3 days. Resistive vibration exercise during bed rest impedes bone loss and restricts increases in bone resorption markers whilst increasing bone formation. INTRODUCTION: To investigate the effectiveness of a resistive vibration exercise (RVE) countermeasure during prolonged bed rest using serum markers of bone metabolism and whole-body dual X-ray absorptiometry (DXA) as endpoints. METHODS: Twenty healthy male subjects underwent 8 weeks of bed rest with 12 months follow-up. Ten subjects performed RVE. Blood drawings and DXA measures were conducted regularly during and after bed rest. RESULTS: Bone resorption increased in the CTRL group with a less severe increase in the RVE group (p = 0.0004). Bone formation markers increased in the RVE group but decreased marginally in the CTRL group (p < 0.0001). At the end of bed rest, the CTRL group showed significant loss in leg bone mass (-1.8(0.9)%, p = 0.042) whereas the RVE group did not (-0.7(0.8)%, p = 0.405) although the difference between the groups was not significant (p = 0.12). CONCLUSIONS: The results suggest the countermeasure restricts increases in bone resorption, increased bone formation, and reduced bone loss during bed rest.

Comparison of CT colonography, colonoscopy, sigmoidoscopy and faecal occult blood tests for the detection of advanced adenoma in an average risk population.

BACKGROUND AND AIMS: This prospective trial was designed to compare the performance characteristics of five different screening tests in parallel for the detection of advanced colonic neoplasia: CT colonography (CTC), colonoscopy (OC), flexible sigmoidoscopy (FS), faecal immunochemical stool testing (FIT) and faecal occult blood testing (FOBT). METHODS: Average risk adults provided stool specimens for FOBT and FIT, and underwent same-day low-dose 64-multidetector row CTC and OC using segmentally unblinded OC as the standard of reference. Sensitivities and specificities were calculated for each single test, and for combinations of FS and stool tests. CTC radiation exposure was measured, and patient comfort levels and preferences were assessed by questionnaire. RESULTS: 221 adenomas were detected in 307 subjects who completed CTC (mean radiation dose, 4.5 mSv) and OC; 269 patients provided stool samples for both FOBT and FIT. Sensitivities of OC, CTC, FS, FIT and FOBT for advanced colonic neoplasia were 100% (95% CI 88.4% to 100%), 96.7% (82.8% to 99.9%), 83.3% (95% CI 65.3% to 94.4%), 32% (95% CI 14.9% to 53.5) and 20% (95% CI 6.8% to 40.7%), respectively. Combination of FS with FOBT or FIT led to no relevant increase in sensitivity. 12 of 45 advanced adenomas were smaller than 10 mm. 46% of patients preferred CTC and 37% preferred OC (p<0.001). CONCLUSIONS: High-resolution and low-dose CTC is feasible for colorectal cancer screening and reaches sensitivities comparable with OC for polyps >5 mm. For patients who refuse full bowel preparation and OC or CTC, FS should be preferred over stool tests. However, in cases where stool tests are performed, FIT should be recommended rather than FOBT.

Chicken beta B1-crystallin gene expression: presence of conserved functional polyomavirus enhancer-like and octamer binding-like promoter elements found in non-lens genes.

Expression of the chicken beta B1-crystallin gene was examined. Northern (RNA) blot and primer extension analyses showed that while abundant in the lens, the beta B1 mRNA is absent from the liver, brain, heart, skeletal muscle, and fibroblasts of the chicken embryo, suggesting lens specificity. Promoter fragments ranging from 434 to 126 bp of 5'-flanking sequence (plus 30 bp of exon 1) of the beta B1 gene fused to the bacterial chloramphenicol acetyltransferase gene functioned much more efficiently in transfected embryonic chicken lens epithelial cells than in transfected primary muscle fibroblasts or HeLa cells. Transient expression of recombinant plasmids in cultured lens cells, DNase I footprinting, in vitro transcription in a HeLa cell extract, and gel mobility shift assays were used to identify putative functional promoter elements of the beta B1-crystallin gene. Sequence analysis revealed a number of potential regulatory elements between positions -126 and -53 of the beta B1 promoter, including two Sp1 sites, two octamer binding sequence-like sites (OL-1 and OL-2), and two polyomavirus enhancer-like sites (PL-1 and PL-2). Deletion and site-specific mutation experiments established the functional importance of PL-1 (-116 to -102), PL-2 (-90 to -76), and OL-2 (-75 to -68). DNase I footprinting using a lens or a HeLa cell nuclear extract and gel mobility shifts using a lens nuclear extract indicated the presence of putative lens transcription factors binding to these DNA sequences. Competition experiments provided evidence that PL-1 and PL-2 recognize the same or very similar factors, while OL-2 recognizes a different factor. Our data suggest that the same or closely related transcription factors found in many tissues are used for expression of the chicken beta B1-crystallin gene in the lens.

Vitamin D deficiency associated with number of neurofibromas in neurofibromatosis 1.

Neurofibromatosis 1 (NF1) is a tumour suppressor gene syndrome characterized by multiple cutaneous and plexiform neurofibromas. Focal osseous abnormalities, short stature, and decreased bone mineral density are also frequent in people with NF1. We measured serum 25-hydroxyvitamin D concentrations in 55 patients with NF1 and 58 healthy controls, and correlated the findings in the patients with NF1 with their estimated number of dermal neurofibromas. Geometric mean (SD) serum 25-hydroxyvitamin D concentration was 14.0 (1.6) ng/mL among the patients with NF1 compared with 31.4 (1.7) ng/mL among healthy controls (p<<0.0001). The serum vitamin D concentration and number of dermal neurofibromas reported by patients with NF1 were inversely correlated (Spearman's rho = -0.572, p<0.00001). The occurrence of low serum vitamin D concentrations in people with NF1, especially those with many dermal neurofibromas, may provide new pathogenic insights and have important therapeutic implications.

Multicenter evaluation of a new 4th generation HIV screening assay Elecsys HIV combi.

Fourth-generation screening assays which permit a simultaneous detection of human immunodeficiency virus (HIV) antigen and antibody reduce the diagnostic window on average by four days in comparison to third-generation antibody assays. Recently, the new automated Elecsys HIV combi was compared in a multicenter study to alternative fourth- and third-generation assays, p24 antigen test and HIV-1 RNA RT-PCR. A total of 104 serocon-version panels, samples of the acute phase of infection after seroconversion (n = 33), anti-HIV-1 positive specimens (n = 572) from patients in different stages of the disease, 535 subtyped samples from different geographical locations, including group M (subtypes A-J) and group O, anti-HIV-2 positive sera (n = 364), dilutions of cell culture supernatants (n = 60) infected with different HIV-1 subtypes, selected performance panels, 8406 unselected samples from blood donors originating from different blood transfusion centers, 3810 unselected sera from daily routine and from hospitalized patients, 9927 unselected samples from South Africa and 1943 potentially interfering samples were tested with the Elecsys HIV combi. Elecsys HIV combi showed a comparable sensitivity to HIV-1 Ag stand-alone assays for early detection of HIV infection in seroconversion panels. The mean time delay of Elecsys HIV combi (last negative sample + 1 day) in comparison to HIV-1 RT-PCR for 92 panels tested with both methods was 3.23 days. The diagnostic window was reduced with Elecsys HIV combi between 1.56 and 5.32 days in comparison to third-generation assays. The specificity of Elecsys HIV combi in blood donors was 99.80% after repeated testing. Our results show that a fourth-generation assay with improved specificity and sensitivity like the Elecsys HIV combi is suitable for blood donor screening due to its low number of false positives and since it detects HIV p24 antigen with a comparable sensitivity to single antigen assays.

Chicken beta B1 crystallin: gene sequence and evidence for functional conservation of promoter activity between chicken and mouse.

The complete sequence was determined for the chicken beta B1-crystallin gene and 2.2 kbp of its 5' flanking region; the chicken gene was then compared to its rat ortholog. Although both have a 5' non-coding exon followed by 5 protein coding exons, the chicken gene is only 2.2 kbp while the rat gene is 13.6 kpb due to longer introns. The coding exons of the chicken beta B1-crystallin gene, like those of the rat and other beta-crystallin genes, each correspond to one of the four 'Greek key' motifs of the encoded protein. The only obvious similarity between the 5' flanking sequences of the chicken and rat beta B1-crystallin gene is associated with the TATA box. A CR1 repetitive element is present at positions -559 to -730 of the chicken beta B1-crystallin gene. In vivo footprinting using dimethyl sulfate/ligation mediated PCR showed that the PL-1 (-116/-102), PL-2 (-90/-76), OL-2 (-75/-68) and OL-1 (-125/-118) control elements identified previously (Roth et al. (1991) Mol. Cell. Biol. 11, 1488-1499) bind proteins within the chromatin of cultured embryonic chicken lens cells. Both -2448/+30 and -434/+30 promoter fragments from the chicken beta B1-crystallin gene directed lens-specific CAT gene expression in a copy number and position independent manner in transgenic mice. These data indicate that the structure and lens-specific expression of this gene are highly conserved although, like other crystallin genes, the 5' flanking sequences have diverged appreciably during evolution.

New series of lipoxins isolated from human eosinophils.

Granulocytes from human eosinophilic donors were incubated with arachidonic acid or 15-hydroxyeicosatetraenoic acid (15-HETE) and stimulated with the ionophore A23187. The eicosanoids were extracted with reversed-phase cartridges and subjected to RP-HPLC analysis. When extracts from eosinophil-enriched populations were analysed and compared with extracts from human neutrophils, three additional peaks were detected which coeluted with 15-hydroxy-delta 13-trans-15H derivatives of leukotriene C4, D4 and E4 in different HPLC systems. The recorded absorbance spectra of the eluted compounds and the standards were identical and showed a maximum at 307 nm which is characteristic for a conjugated tetraene system with a bathochromic shift by the sulfur moiety in alpha-position to the tetraene system. The compound which coeluted with the 15-hydroxy-LTC4 standard was treated with gamma-glutamyltransferase and converted to the corresponding leukotriene D4 derivative. The results indicate that interaction between the 5- and 15-lipoxygenase pathways leads to the formation of a new series of arachidonic acid metabolites in human eosinophils. Since the biosynthetic route is similar to that of lipoxin A4 and lipoxin B4, we suggest the trivial names lipoxin C4, D4 and E4.

Risk factors in alcohol associated breast cancer: alcohol dehydrogenase polymorphism and estrogens.

Chronic alcohol consumption is associated with an increased risk for breast cancer, even if consumed in moderate doses. Since acetaldehyde is a carcinogenic factor associated with chronic alcohol consumption, individuals with the alcohol dehydrogenase 1C*1 allele (ADH1C*1 allele) seem to be at particular risk, since this allele encodes for a rapidly ethanol metabolizing enzyme leading to increased acetaldehyde levels. Since recent epidemiological studies demonstrated an increased risk for breast cancer for individuals with the ADH1C*1 allele, we have investigated here ADH1C genotypes in moderate alcohol consumers. Furthermore, estradiols are also known risk factors for breast cancer and acute alcohol ingestion in high doses results in increased serum estradiol concentrations. Thus, in the present study, we tested the effect of low ethanol doses on estrogen serum concentrations. We analyzed the ADH1C genotype in 117 moderate alcohol consumers with breast cancer and in 111 age-matched women with alcohol associated diseases without cancer (74 cirrhotics, 22 patients with pancreatitis and 15 alcohol dependent patients). In addition, 107 healthy controls were studied. Genotyping of the ADH1C-locus was performed using polymerase chain reaction-based restriction fragment length polymorphism methods on leukocyte DNA. To study the effects of ethanol on estradiol levels, ethanol in a dose of 0.225 g/kg body weight was given orally to 8 premenopausal women at various time points of their menstrual cycle. Thereafter estradiol serum concentrations were measured over time. The allele frequency of the ADH1C*1 allele was found to be significantly increased in moderate alcohol consumers with breast cancer as compared to age-matched alcoholic controls without cancer (62% vs. 41.9%, p=0.0035). Women with the ADH1C*1,1 genotype were found to be 1.8 times more at risk for breast cancer than those with another genotype (95% CI 1.431-2.330, p<0.001). Oral ethanol increased serum estradiol levels significantly by 27-38%. The data demonstrate that moderate alcohol consumers with the ADH1C*1 allele have an increased risk to develop breast cancer and even small amounts of alcohol increase serum estradiol levels significantly in premenopausal women especially in the midphase of the menstrual cycle.

Immunochemiluminometric assay with two monoclonal antibodies against the N-terminal sequence of human parathyroid hormone.

We have developed an immunochemiluminometric assay (ICMA) with two monoclonal antibodies for the N-terminal sequence of human parathyroid hormone (hPTH). One monoclonal antibody (A1-70) was physically adsorbed onto polystyrene beads, the other (B1-70) was labelled with acridinium ester and synthetic hPTH (1-38) was used as standard. This assay has cross-reactions with synthetic hPTH (1-34) and hPTH (1-84) but no cross-reactions with hPTH (4-16), (28-48), (39-84), (44-68), (53-84) and hPTH-rP (1-86). The assay detection limit is 0.4 pmol/l. The normal range is 1.3-12 pmol/l based on 72 normal volunteers. About 91% of study patients (n = 58) with surgically proven primary hyperparathyroidism (1 degree HPT) had PTH values above normal and one of them showed a low normal intact PTH value but elevated PTH values with use of this assay. After immunoabsorption of plasma samples from patients with secondary hyperparathyroidism (2 degrees HPT) on hemodialysis with polystyrene beads containing antibodies against hPTH (39-84), some patients still showed significant amounts of PTH in this new ICMA but not intact PTH. The data reveal that significant amounts of amino-terminal immunoreactive PTH fragments rarely exist in 1 degree HPT but are present in some patients with 2 degrees HPT. The major advantage of this assay is to measure both amino-terminal PTH fragments and intact PTH with no interference from carboxy-terminal PTH fragments because two anti-N-terminal hormone sequence monoclonal antibodies are used.

Synthesis of azathia analogues of platelet activating factor with polyheterosidechains.

The synthesis of azathia analogues of the platelet activating factor with oxygen and sulphur-containing sidechains is reported. The starting point is 1-acetylthio-3-hydroxy-2-propaneamine-HCl, which permits the formation of the thioether and the acetamido linkage in one step. The phosphocholine part is introduced via 2-chloro-2-oxo-1,3,2-dioxaphospholane and subsequent ring opening with trimethylamine under pressure.

Human anti-mouse antibodies: pitfalls in tumor marker measurement and strategies for enhanced assay robustness; including results with Elecsys CEA.

Therapies using monoclonal antibodies may have undesirable consequences for the diagnostic use of tumor markers. These effects can be minimised by employing chimeric antibodies as well as special interference eliminating reagents. Human Anti-Mouse Antibodies (HAMA) are produced as a result of the immune response of a patient to treatment with murine monoclonal antibodies. The interaction of HAMA with the murine monoclonal antibodies of a tumor marker assay can simulate (false) positive or negative results leading to misdiagnosis and to inadequate disease management of a patient. To avoid HAMA-interferences "Roche Diagnostics" established a three-component-system: The use of chimeric antibodies, the interference elimination, which is realised in the parameters most frequently used like CEA and TSH. By employing such a chimeric antibody, Elecsys CEA proved to be extremely robust against HAMA-interferences. With 20 clinical relevant samples from different Mab-approaches, no HAMA-interference was observed. By fragmentation of the antibodies, i.e., elimination of the constant region and using monovalent fab-fragments (antigen binding fragment) combined with the addition of special blocking reagents all not-chimerized, Elecsys assays showed comparable results to chimerisation. This could also be shown with 20 clinical relevant samples.

Technical performance of the Elecsys CA 72-4 test--development and field study.

Tumor-associated glycoprotein (TAG) 72 is a mucin-like protein of high molecular weight (220-400 kd). Elevated serum levels of TAG72 are preferentially observed in patients suffering from gastric cancer. Additionally the determination of TAG72 may be a helpful tool in the management of patients suffering from mucinous ovarian cancer, in whom the clinical sensitivity of CA125 is low. The new Elecsys CA72-4 assay-available as Elecsys 2010 and 1010--was evaluated in a first field study. The test has a wide measuring range (300 U/ml) and low detection limit (0.5 U/ml) which favours its routine use. Typical precision values are 2% for intra-assay, 4% for inter-assay and 6% for inter-instrument-precision. Method comparisons to Enzymun-Test CA72-4 showed a correlation between 0.91 and 0.96. The correlation to a commercially available RIA was 0.8. With human ascites material no Hook-effect was observed up to 20,000 U/ml. No Hama-interference with clinically relevant HAMA-samples was detected.

Validation of the first automated chemiluminescence protein-binding assay for the detection of 25-hydroxycalciferol.

BACKGROUND: Measurement of 25-hydroxyvitamin D, 25(OH)D is the ideal parameter to indicate the access of the organism to vitamin D. Numerous studies have shown that serum levels of 25(OH)D are the best markers of vitamin D deficiency, normal vitamin D supply or vitamin D intoxication. The aim of the study was to validate a beta-site version of the first fully automated chemiluminescence protein-binding assay (CLPBA) for the detection of 25-hydroxycalciferol. METHODS: The newly developed CLPBA run on the Nichols Advantage Specialty Systems was compared to an inhouse radioimmunoassay (RIA), focussing on the major assay features such as imprecision, functional sensitivity, linearity, method comparison and suitability of serum or EDTA-plasma as well as establishing a preliminary reference range. RESULTS: Within-run imprecision is approximately 4.5% and total imprecision approximately 6% respectively (NCCLS protocol), functional sensitivity 6.8 microg/l. With mean recovery values of 96.9% and 98.7% for two diluted serum samples linearity is given over the measuring range. Due to different calibrations used for RIA and CLPBA the CLPBA reads approximately 70% lower (CLPBA = 0.321xRIA + 0.571, n = 469) but correlates well with the RIA (r = 0.9045). Method comparison with HPLC reveals a regression line of CLPBA = 0.8921xHPLC + 0.1358 (n = 54, r = 0.9117). Serum or EDTA-plasma is not equally suitable. Plasma samples read on average 5 microg/l higher than serum samples. The preliminary reference range is 11 microg/l to 84 microg/l (95% of all values). CONCLUSION: The validated 25(OH)D CLPBA is a very promising alternative to established commercially available 25(OH)D measurements and will, with its use on a fully automated platform, simplify the reliable quantification of 25-hydroxycalciferol significantly.

Internal thoracoplasty. A new procedure.

STUDY DESIGN: The efficacy of performing a thoracoplasty from within the thoracotomy during anterior surgery for scoliosis was investigated. OBJECTIVES: Patients were prospectively studied to determine the possible complications and morbidity of the procedure, and were compared to a similar group of patients that previously underwent same-day anterior and posterior procedures for scoliosis, but without thoracoplasty. Description of the technique is presented. SUMMARY OF BACKGROUND DATA: The seven study patients had uneventful intra- and post-operative courses. For the posterior procedure (CD instrumentation), only morselized rib graft was used, obviating the need for iliac graft. RESULTS: There was no greater rate or additional types of complications in the study group compared to the control group, except one additional day of thoracotomy tube retention. CONCLUSIONS: When same day anterior and posterior procedures are to be performed for scoliosis, internal thoracoplasty is indicated, as a source of autogenous bone and for cosmesis.

Risk analysis for the importation of veterinary biologicals into the United States of America.

International trade in veterinary biological products has been restricted by the following factors: a) concerns that contaminated products could result in the introduction of foreign animal disease agents into the importing country b) differences between countries in the technical requirements for product registration. The provisions of the North American Free Trade Agreement (NAFTA) and the General Agreement on Tariffs and Trade (GATT: now the World Trade Organisation [WTO]) require importation decisions to be science-based and transparent. This requires regulatory agencies to implement valid, credible, and science-based risk analysis models for decision-making. The Veterinary Biologics section of the United States Department of Agriculture, Animal and Plant Health Inspection Service, currently uses a formalized risk analysis model to evaluate the safety risks associated with proposals to field test and license new and biotechnology-derived veterinary biological products. This model for evaluating field tests has been modified to evaluate proposals to import veterinary biological products into the United States of America. The authors describe this risk analysis model, which was specifically designed to evaluate the risks of importing veterinary biological products potentially contaminated with foreign animal disease agents.

Single-dose oral calcitriol and changes of plasma 1,84iPTH in uremic children.

Both intravenous and oral 1,25(OH)2 D3 pulse therapy are effective in decreasing iPTH in patients with chronic renal failure. In order to understand why intermittent application of calcitriol is effective, we investigated 10 children with advanced renal failure (4 female, 6 male; median age 6.5 [3-16] years; body surface area 0.58-1.57m2; CCR 7 [5-47] mL/min/1.73m2) with elevated baseline concentrations of 1,84iPTH (median 63.5 [9.4-300] pmol/L). After a standard dose of 2 micrograms calcitriol per os (equal to 1.27-3.45 micrograms/m2), serum 1,25(OH)2D3 concentrations increased. The peak concentration occurred after 6 h (3-12), and 1,25(OH)2D3 serum levels returned to baseline by 48 h. 1,84iPTH concentrations were significantly suppressed by 6-72 h. The median maximal decrease was 51.4% of baseline (22.3%-74%). The decrement was a function of baseline 1,84iPTH, but not of 1,25(OH)2D3 serum peak concentration, area under the curve, body surface area, or change in ionized serum calcium. We conclude: (i) oral 1,25(OH)2D3 has a prolonged (up to 72 h) suppressive effect on 1,84iPTH concentrations in uremic patients, and (ii) the wide interindividual variation in suppression of 1,84iPTH was not explained by the kinetics of 1,25(OH)2D3 concentration, which implies that additional factors influence the 1,84iPTH response to 1,25(OH)2D3.