Screening for mutations in the exon 26 of the apolipoprotein B gene in hypercholesterolemic finnish families by the single-strand conformation polymorphism method

To date, the only known apolipoprotein B (apo B) mutation causing hypercholesteroletnia is the apo B 3500 Arg → Gln or the familial defective apo B (FDB) mutation. This mutation has not been detected in the Finnish population. We have set up a systematic single-strand conformation polymorphism (SSCP) analysis-based screening method to search for other mutations in the exon 26 of the apo B gene in 21 Finnish hypercholesterolemic probands. The 7572-bp exon 26 covers half of the coding region of the gene including the DNA sequence coding for the putative low-density lipoprotein (LDL) receptor binding site on the apo B protein. Exon 26 was amplified as six 1190- to 1435-bp fragments, each of which was further split into three smaller 213- to 579-bp segments by restriction enzymes. These digestion products were run on nondenaturing polyacrylamide gels using at least three different electrophoretic ccnditions and autoradiographed. All previously known genetic variants in the exon 26 were detected by the SSCP method. A C→T change at nucleotide 7064, in complete association with the XbaI site, was characterized by direct sequencing. This variant did not affect the amino acid sequence of the apo B protein. The SSCP-based procedure appears suitable for systematic screening for DNA sequence changes in large coding regions. © 1994 Wiley-Liss, Inc.     

Environmental tobacco smoke in Finnish restaurants and bars before and after smoking restrictions were introduced

OBJECTIVES: The Finnish Tobacco Act was amended on 1 March 2000 to include restrictions on smoking in restaurants and bars. To evaluate the effectiveness of the restrictions, environmental tobacco smoke (ETS) concentrations in restaurants and bars were measured prior and after the amended Act entered into force. The Act was enforced in stages so that all stages were effective on 1 July 2003. According to the Act, smoking is prohibited in all Finnish restaurants and bars with certain exceptions. Smoking may be allowed in establishments where the service area is not larger than 50 m(2) if the exposure of employees working there to ETS can be prevented. On premises with larger service area, smoking may be allowed on 50% of the service area, provided tobacco smoke does not spread into the area where smoking is prohibited. At bar counters or gambling tables smoking is not allowed, if the spreading of tobacco smoke cannot be restricted to the employee side of the counter. Therefore, according to the Act all areas where smoking is prohibited are to be smoke-free. METHODS: Establishments with a serving area larger than 100 m(2) were selected for the present study. The evaluation both before and after the enforcement of the Act included the following: The ventilation rate was first measured in each establishment. Then 3-5 area samplers, depending on the layout, were placed in locations that best described the establishment and the working areas of the personnel. The measurements were performed twice at each establishment, during peak hours. The sample collection time was 4 h during which the guests and the cigarettes smoked were counted. The air samples were analysed for nicotine, 3-ethenylpyridine (3-EP) and total volatile organic compounds (TVOC) by thermodesorption-gas chromatography-mass spectrometry. RESULTS: Altogether 20 restaurants and bars situated in three Finnish cities participated in the study out of which 16 participated during all four measurement periods. None of the establishments had introduced a total ban on smoking and they all had reserved only the smallest area allowed by the Finnish Tobacco Act as the smoke-free area. The measured geometric mean (GM) nicotine concentration in all participating establishments was 7.1 microg m(-3) before the amended act was in force and 7.3 microg m(-3) after all stages of the Act had been enforced. The GM concentration of nicotine in food and dining restaurants was 0.7 microg m(-3) before and 0.6 microg m(-3) after the enforcement of the Act, in bars and taverns the concentrations were 10.6 and 12.7 microg m(-3), and in discos and night-clubs 15.2 and 8.1 microg m(-3), respectively. The GM nicotine concentrations measured in the smoke-free sections varied between 2.9 and 3 microg m(-3). 3-EP concentrations measured correlated well with the nicotine concentrations and were approximately one-fifth of the nicotine concentrations. The measurements showed higher TVOC values in the smoking sections than in the smoke-free sections, but because there are many other sources of TVOC compounds in restaurants and bars TVOC cannot be regarded as a marker for ETS. CONCLUSIONS: The overall air nicotine concentration decreased in 10 out of the 18 establishments that participated in the study both before and after all stages of the amended Act had been in force. Structural changes or changes to the ventilation systems had been carried out in nine of these establishments, i.e. the smoke-free sections were actually non-smoking and were mainly separated from other sections by signs and very little was done to keep the smoke from spreading into the smoke-free sections. In four establishments, the highest air nicotine concentration was measured in the smoke-free section. In 10 establishments, the air nicotine concentration at bar counters had dropped after the Act. Exposure of the workers and the public to ETS was, therefore, not reduced as intended by the Finnish legislature. Thus, it seems obvious from the present study that improving ventilation will not be a solution to restricting tobacco smoke from reaching smoke-free areas and physical barriers separating smoking from smoke-free areas are required.     

The predictive value of megakaryocytic and erythroid colony formation and platelet function tests on the risk of thromboembolic and bleeding complications in essential thrombocythaemia

The predictive value of spontaneous in vitro colony formation of megakaryocytic and erythroid progenitors (154 patients), and defective platelet aggregation responses (55 patients) on the risk of thrombohaemorrhagic complications in patients with essential thrombocythaemia (ET) was evaluated retrospectively. In the in vitro cultures of haematopoietic progenitors, 114/154 patients (74%) showed either spontaneous megakaryocytic or erythroid colony formation or both. Forty-three per cent of patients with any spontaneous colony growth and only 20% of those without this phenomenon had an arterial thrombosis at diagnosis or during the follow-up (P = 0.02). In the whole patient group neither spontaneous megakaryocytic nor spontaneous erythroid colony formation alone predicted the risk of arterial thrombosis. In patients younger than 45 yr of age, the prognostic value of spontaneous megakaryocytic growth was statistically significant: 44% of the patients with spontaneous megakaryocytic colony formation, but only 14% of those without it, experienced arterial thrombosis (P = 0.04). The presence of spontaneous colony formation had no effect on the risk of bleeding complications. Forty-one of the 55 patients (75%) showed abnormalities in the platelet aggregation responses. There was no statistically significant correlation between the platelet function response and the risk of bleeding or thrombotic complications. No correlation was found between the platelet aggregation responses and the presence of spontaneous colony growth. In conclusion, spontaneous colony formation indicated an increased risk of thrombohaemorragic events but the platelet function test had no predictive value for these complications.     

Prevention of bone loss after allogeneic stem cell transplantation by calcium, vitamin D, and sex hormone replacement with or without pamidronate

CONTEXT: In controlled studies, bisphosphonates have been used to prevent bone loss after solid organ transplantations but not in conjunction with stem cell transplantation (SCT). OBJECTIVE: The objective of the study was to test whether additional iv pamidronate would prevent bone loss associated with SCT more effectively than the combination of calcium, vitamin D, and sex steroid replacement therapy alone. SETTING: The study was carried out at the Helsinki University Central Hospital. PATIENTS, DESIGN, INTERVENTION: Ninety-nine adult recipients of allogeneic SCT were randomized by age and gender into two groups. In one group, the patients received 1000 mg calcium carbonate and 800 IU vitamin D daily, and females received estrogen and males received testosterone replacement therapy. In another group, the patients received the same treatments plus six iv infusions of 60 mg pamidronate before and 1, 2, 3, 6, and 9 months after SCT. MAIN OUTCOME MEASURES: Bone mineral density (BMD) of the lumbar spine and the upper femur, measured by dual-energy x-ray absorptiometry, and bone turnover markers were followed for 12 months. RESULTS: In the pamidronate group, lumbar spine BMD remained stable but decreased in the other group by 2.9% at 12 months (P = 0.0084 between the groups over time). Total hip BMD reduced 5.1% in the pamidronate group and 7.8% in the other group by 12 months (P = 0.0015), and femoral neck BMD reduced 4.2 and 6.2%, respectively (P = 0.074). In the pamidronate group, serum type I procollagen amino-terminal propeptide (P = 0.032 between the groups over time) and urinary type I collagen amino-terminal telopeptide (P = 0.035) decreased 79 and 68% during the first 3 months, and remained lowered thereafter, but did not change in the other group. CONCLUSIONS: The recipients of allogeneic SCT receiving additional pamidronate sustain less bone loss than those treated with calcium, vitamin D, and sex steroid replacement alone. Despite all the efforts, however, bone loss is not totally abolished at the hip.     

Retrospective comparison of reduced-intensity conditioning and conventional high-dose conditioning for allogeneic hematopoietic stem cell transplantation using HLA-identical sibling donors in myelodysplastic syndromes

In this multicenter retrospective study, the outcomes of 836 patients with myelodysplastic syndrome (MDS) who underwent transplantation with a human leukocyte antigen (HLA)-identical sibling donor were analyzed according to 2 types of conditioning: reduced-intensity conditioning (RIC) in 215 patients, and standard myeloablative (or high-dose) conditioning (SMC) in 621 patients. In multivariate analysis, the 3-year relapse rate was significantly increased after RIC (hazard ratio [HR], 1.64; 95% confidence interval [95% CI], 1.2-2.2; P = .001), but the 3-year nonrelapse mortality (NRM) rate was decreased in the RIC group (HR, 0.61; 95% CI, 0.41-0.91; P = .015). The 3-year probabilities of progression-free and overall survivals were similar in both groups (39% after SMC vs 33% in RIC; multivariate P = .9; and 45% vs 41%, respectively; P = .8). In conclusion, the lower 3-year NRM after RIC is encouraging, since these patients were older (age > 50 years in 73% RIC vs 28% in SMC, P < .001) and had more adverse pretransplantation variables. However, based on the higher risk of relapse, patients with no contraindications for SMC should not receive RIC outside of prospective randomized trials, which are needed to establish the position of RIC-based transplantation in the treatment of patients with MDS.