ABSTRACT
INTRODUCTION: This study describes deaths among Danish soldiers in international operations 2002-2018. Having been part of UN and later NATO forces in ex-Yugoslavia, in 2002 the first Danish contingent took part in the International Security Assistance Force mission in Afghanistan as well as Iraq. The changing role of the Danish military in international operations meant casualties, in numbers that had not yet been experienced, and necessitated a review of our procedures for handling fatalities in the military. METHODS: The study is a retrospective review of autopsy reports, Military Police reports and medical reports, and the purpose is to examine all Danish fatalities in international operations in 2002-2018 to identify potential areas of improving treatment and protection and to review the contribution of the autopsies. The mechanism of injury, the fatal injuries and causes of death and the time of death within the chain of evacuation were identified. Casualties dying at any time from site of injury until definitive care were included. RESULTS: A total of 53 soldiers died from injuries during international operations in the years 2002-2018. The majority of these (43) died from combat injuries and 10 from accidents. Four of the victims with combat injuries were not autopsied. The majority (36) of the combat deaths were caused by blast/explosions (improvised explosive devices, rocket propelled grenades, fragments), while 7 were caused by bullets. 39 combat victims died instantly on the site or at the arrival to the field hospital, 4 were treated in field hospital and 2 of these were transported back to Denmark. CONCLUSIONS: Most combat fatalities result from fragmentation and blast injury. Forensic autopsies provide valuable information regarding injuries, weaponry, the efficiency of protective equipment and the quality of medical intervention in military fatalities and are recommended in all military fatalities in order to prevent avoidable casualties in the future.
ABSTRACT
Background Transdermal opioids are widely used among elderly adults with chronic pain. However, transdermal patches may be involved in a significant proportion of opioid-related patient safety incidents, as the application process includes several subprocesses, each associated with an individual risk of error. Objective The aim was to obtain specific knowledge on patient safety incidents related to transdermal opioid treatment within both the primary care sector and the hospital sector in Denmark. Setting The study is descriptive with data provided by the Danish Patient Safety Database. Methods We manually retrieved all patient safety incidents concerning transdermal opioids reported for 2018 from (1) the hospital sector and (2) the primary care sector. Study data were collected and managed using REDCap electronic data capture tools. Main outcome measure The available information for each incident was sorted into the following categories: location, medication process, type of problem, outcome at time of reporting, and outcome classification. Results A total of 866 patient safety incidents involving transdermal opioids were reported to the Danish Patient Safety Database in 2018. No fatal incidents were present in the database. In 386 cases, the incidents were reported as harmful, and these 386 cases were analysed. Most reports came from the primary care sector (nursing home, home care or social housing). The majority of incidents were related to the administration of the patch in the medication process, and the most prevalent problem was the omission of doses. Conclusion This study has demonstrated that the administration of transdermal opioids is challenging and may cause harm, particularly in the primary care sector. To improve patient safety, optimized systems, including guidelines on drug management and the continuing education of healthcare personnel in transdermal opioid management, are necessary. These guidelines should preferably incorporate reminders and checklists, since the omission of doses was the most reported problem.
Subject(s)
Analgesics, Opioid , Patient Safety , Adult , Aged , Analgesics, Opioid/adverse effects , Databases, Factual , Denmark/epidemiology , Hospitals , HumansABSTRACT
SETTING: The management of multidrug-resistant tuberculosis (MDR-TB) is strictly regulated in Norway. However, nationwide studies of the epidemic are lacking. OBJECTIVE: To describe the MDR-TB epidemic in Norway over two decades. DESIGN: Retrospective analysis of data on MDR-TB cases in Norway, 1995-2014, obtained from the national registry, patient records and the reference laboratory, with genotyping and cluster analysis data. Data for non-MDR-TB cases were collected from the national registry. RESULTS: Of 4427 TB cases, 89 (2.0%) had MDR-TB, 7% of whom had extensively drug-resistant TB (XDR-TB) and 24% pre-XDR-TB. Of the 89 MDR-TB cases, 96% were immigrants, mainly from the Horn of Africa or the former Soviet Union (FSU); 37% had smear-positive TB; and 4% were human immunodeficiency virus co-infected. Of the 19% infected in Norway, the majority belonged to a Delhi/Central Asian lineage cluster in a local Somali community. Among the MDR-TB cases, smear-positive TB and FSU origin were independent risk factors for XDR/pre-XDR-TB. Treatment was successful in 66%; 17% were lost to follow-up, with illicit drug use and adolescence being independent risk factors. Forty-four per cent of patients treated with linezolid discontinued treatment due to adverse effects. CONCLUSION: MDR-TB is rare in Norway and is predominantly seen in immigrants from the Horn of Africa and FSU. Domestic transmission outside immigrant populations is minimal.
Subject(s)
Epidemics , Extensively Drug-Resistant Tuberculosis/epidemiology , HIV Infections/epidemiology , Tuberculosis, Multidrug-Resistant/epidemiology , Adolescent , Adult , Africa/ethnology , Antitubercular Agents/therapeutic use , Child , Child, Preschool , Cluster Analysis , Emigrants and Immigrants , Extensively Drug-Resistant Tuberculosis/drug therapy , Female , Follow-Up Studies , Genotyping Techniques , HIV Infections/drug therapy , Humans , Linezolid/therapeutic use , Lost to Follow-Up , Male , Middle Aged , Norway/epidemiology , Retrospective Studies , Risk Factors , Tuberculosis, Multidrug-Resistant/drug therapy , USSR/ethnology , Young AdultABSTRACT
The manuscript presents the International Guidelines developed by the Working Group on Personal Injury and Damage under the patronage of the International Academy of Legal Medicine (IALM) regarding the Methods of Ascertainment of any suspected Whiplash-Associated Disorders (WAD).The document includes a detailed description of the logical and methodological steps of the ascertainment process as well as a synoptic diagram in the form of Flow Chart.
Subject(s)
Whiplash Injuries/diagnosis , Humans , Medical History Taking/standards , Physical Examination/standards , Visual Analog ScaleABSTRACT
The modified International Knee Documentation Committee Subjective Knee Form (Pedi-IKDC) is a widely used patient-reported tool ranging on a scale from 0 to 100. We aimed to translate Pedi-IKDC into Danish and assess its reproducibility and responsiveness in children with knee disorders. The translation complied with the international guidelines. Reproducibility was assessed in 53 children (15 years) responding Pedi-IKDC at baseline and after 3-14 days. For analysis of responsiveness, 94 children (15 years) responded Pedi-IKDC again after 3 months. Test-retest reliability was excellent. Intraclass correlation coefficient was 0.9, standard error of measurement was 4.1 points, and smallest detectable change (SDC) was 11.3 points. Evaluating responsiveness as a large effect was found in children reporting improvement compared with children reporting deterioration. The change score was correlated to the external anchor Global Rating Scale consisting of 15 answers from -7 "A very great deal worse" to +7 "A very great deal better," with a Spearmen's rho of 0.45 (P > 0.001). The minimal clinically important changes was 12.0. In conclusion, excellent test-retest reproducibility was found at group level, but at individual level the SDC was high. The Pedi-IKDC showed adequate responsiveness and is suitable for assessing improvement or deterioration in children with knee disorders.
Subject(s)
Anterior Cruciate Ligament Injuries/physiopathology , Patellofemoral Pain Syndrome/physiopathology , Tibial Meniscus Injuries/physiopathology , Adolescent , Child , Cultural Competency , Denmark , Female , Humans , Knee Injuries/physiopathology , Male , Patient Outcome Assessment , Reproducibility of Results , Surveys and Questionnaires , TranslationsSubject(s)
Adrenal Cortex Hormones/therapeutic use , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Methotrexate/therapeutic use , Osteomyelitis/drug therapy , Child , Cohort Studies , Female , Humans , Male , Norway/epidemiology , Osteomyelitis/epidemiology , Recurrence , Retrospective Studies , Treatment Outcome , Tumor Necrosis Factor-alpha/antagonists & inhibitorsABSTRACT
Enterovirus D68 (EV-D68), phylogenetic clade B was identified in nasopharyngeal specimens of two cases of severe acute flaccid myelitis. The cases were six and five years-old and occurred in September and November 2014. EV-D68 is increasingly associated with acute flaccid myelitis in children, most cases being reported in the United States. Awareness of this possible neurological complication of enterovirus D68 infection is needed.
Subject(s)
Enterovirus D, Human/genetics , Enterovirus D, Human/isolation & purification , Enterovirus Infections/diagnosis , Myelitis/diagnosis , Nasopharynx/virology , Paralysis/diagnosis , Child , Child, Preschool , Electroencephalography , Enterovirus D, Human/classification , Enterovirus Infections/virology , Female , Humans , Magnetic Resonance Imaging , Myelitis/virology , Norway , Paralysis/virology , Reverse Transcriptase Polymerase Chain Reaction , Seasons , Sequence Analysis, DNA , Severity of Illness IndexABSTRACT
Chronic lymphocytic leukemia (CLL) is an incurable malignancy of mature B cells. One of the major challenges in treatment of CLL is the achievement of a complete remission to prevent relapse of disease originating from cells within lymphoid tissues and subsequent chemoresistance. In search for novel drugs that target CLL cells in protective microenvironments, we performed a fungal extract screen using cocultures of primary CLL cells with bone marrow-derived stromal cells. A secondary metabolite produced by Penicillium aquamarinium was identified as Chaetoglobosin A (ChA), a member of the cytochalasan family that showed preferential induction of apoptosis in CLL cells, even under culture conditions that mimic lymphoid tissues. In vitro testing of 89 CLL cases revealed effective targeting of CLL cells by ChA, independent of bad prognosis characteristics, like 17p deletion or TP53 mutation. To provide insight into its mechanism of action, we showed that ChA targets filamentous actin in CLL cells and thereby induces cell-cycle arrest and inhibits membrane ruffling and cell migration. Our data further revealed that ChA prevents CLL cell activation and sensitizes them for treatment with PI3K and BTK inhibitors, suggesting this compound as a novel potential drug for CLL.
Subject(s)
Apoptosis/drug effects , Cytokinesis/drug effects , Cytoskeleton/drug effects , Indole Alkaloids/pharmacology , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Mycotoxins/pharmacology , Stromal Cells/drug effects , Actins/metabolism , Blotting, Western , Case-Control Studies , Cell Adhesion/drug effects , Cell Cycle/drug effects , Cell Movement/drug effects , Cell Proliferation/drug effects , Chromatography, High Pressure Liquid , Coculture Techniques , Cytoskeleton/metabolism , Flow Cytometry , Fungi/chemistry , Healthy Volunteers , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Leukemia, Lymphocytic, Chronic, B-Cell/metabolism , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Stromal Cells/metabolism , Stromal Cells/pathology , Tumor Cells, CulturedABSTRACT
AIMS/HYPOTHESIS: Many cystic fibrosis patients are vitamin D-insufficient. Cystic fibrosis-related diabetes is a major complication of cystic fibrosis. The literature suggests that vitamin D might possess certain glucose-lowering properties. We aimed to assess the relationship between vitamin D and cystic fibrosis-related glucose intolerance. METHODS: We enrolled 898 cystic fibrosis patients from Sweden, Norway and Denmark. Vitamin D intake was assessed using a seven-day food record. Serum 25-hydroxyvitamin D (s25OHD) and HbA(1c) were measured, and an OGTT was carried out. Multiple linear and logistic regressions were used for HbA(1c) and cystic fibrosis-related diabetes/OGTT result as outcome variables, respectively. Each model was controlled for country, and for known cystic fibrosis-related diabetes risk factors: age, sex, genotype, liver dysfunction, long-term corticosteroid treatment, and lung and pancreatic function. RESULTS: Degree of vitamin D insufficiency (OR 1.36; p = 0.032) and s25OHD < 30 nmol/l (OR 1.79; p = 0.042) were significant risk factors for cystic fibrosis-related diabetes. Accordingly, HbA(1c) value was positively associated with s25OHD < 30 nmol/l and < 50 nmol/l, as well as with degree of vitamin D insufficiency (adjusted R (2) = 20.5% and p < 0.05 in all). In subgroup analyses, s25OHD < 30 nmol/l determined the HbA(1c) value in paediatric patients (adjusted R (2) = 20.2%; p = 0.017), but not in adults. CONCLUSIONS/INTERPRETATION: Vitamin D status is associated with HbA(1c) and diabetes in cystic fibrosis, particularly in children. The study justifies prospective studies on the proposed role of vitamin D deficiency in the pathophysiology of diabetes mellitus.
Subject(s)
Cystic Fibrosis/complications , Diabetes Mellitus/etiology , Diet Records , Vitamin D Deficiency/complications , Adolescent , Child , Child, Preschool , Cohort Studies , Cross-Sectional Studies , Cystic Fibrosis/blood , Female , Glucose Tolerance Test , Glycated Hemoglobin/analysis , Humans , Male , Risk Factors , Scandinavian and Nordic Countries/epidemiology , Severity of Illness Index , Vitamin D/administration & dosage , Vitamin D/blood , Vitamin D Deficiency/blood , Young AdultABSTRACT
BACKGROUND/OBJECTIVES: The hallmark of cystic fibrosis (CF) is chronic lung inflammation. The severity of lung disease is closely correlated with immunoglobulin G (IgG) levels. Beyond its contribution to the bone health, the importance of vitamin D has not been fully recognized owing to the lack of human studies providing evidence of its benefit. In the context of the recently described immunomodulatory functions of vitamin D, we aimed to assess the relationship between vitamin D and IgG levels. SUBJECTS/METHODS: Eight hundred and ninety-six CF patients were included (0.53-65.9 years) from seven centers in Denmark, Norway and Sweden. Serum 25-hydroxyvitamin D (25OHD) and total IgG were measured, spirometry was carried out and vitamin D intake data were gathered using a 7-day dietary food record. Multiple linear regression analyses were performed for IgG and forced expiratory volume in 1λs (FEV1) as dependent variables, and serum 25OHD, daily food and supplemented vitamin D sources of intake as independent variables. The model was controlled for age, gender, genotype, CF-related diabetes, season, infection/colonization status, long-term oral corticosteroid treatment, long-term treatment with macrolide antibiotics, pancreatic insufficient phenotype and body mass index z-score. RESULTS: Serum total IgG levels were negatively associated with serum 25OHD (adjusted R (2) = 0.376; beta = -0.02; P<0.001), supplemented vitamin D intake per kg bodyweight (adjusted R (2) = 0.375; beta = -0.82; P < 0.001) and total vitamin D intake per kg bodyweight (adjusted R (2) = 0.398; beta = -0.60; P = 0.002). Serum 25OHD was positively associated with FEV1 (adjusted R (2) = 0.308; beta = 0.0007; P = 0.025). CONCLUSIONS: Increasing vitamin D intake may positively modulate inflammation in CF. This study supports the proposed role of vitamin D in the immune system during infection and substantiates prospective studies.
Subject(s)
Cystic Fibrosis/blood , Ergocalciferols/blood , Immunoglobulin G/blood , Nutritional Status , Vitamin D/analogs & derivatives , Adolescent , Adult , Aged , Child , Child, Preschool , Cross-Sectional Studies , Cystic Fibrosis/immunology , Cystic Fibrosis/metabolism , Denmark/epidemiology , Dietary Supplements , Ergocalciferols/administration & dosage , Female , Humans , Infant , Male , Middle Aged , Norway/epidemiology , Regression Analysis , Sweden/epidemiology , Vitamin D/administration & dosage , Vitamin D/blood , Young AdultABSTRACT
BACKGROUND: Medication errors can have serious consequences for patients, and medication safety is essential to pharmaceutical care. Insight is needed into the vulnerability of the working process at community pharmacies to identify what causes error incidents, so that the system can be improved to enhance patient safety. METHODS: 40 randomly selected Danish community pharmacies collected data on medication errors. Cases that reached patients were analysed, and the most serious cases were selected for root-cause analyses by an interdisciplinary analysis team. RESULTS: 401 cases had reached patients and a substantial number of them had possible clinical significance. Most of these errors were made in the transcription stage, and the most serious were errors in strength and dosage. The analysis team identified four root causes: handwritten prescriptions; "traps" such as similarities in packaging or names, or strength and dosage stated in misleading ways; lack of effective control of prescription label and medicine; and lack of concentration caused by interruptions. CONCLUSION: A substantial number of the medication errors identified at pharmacies that reach patients have possible clinical significance. Root-cause analysis shows potential for identifying the underlying causes of the incidents and for providing a basis for action to improve patient safety.
Subject(s)
Causality , Medical Records/standards , Medication Errors/prevention & control , Pharmacies/standards , Systems Analysis , Denmark/epidemiology , Drug Packaging/standards , Drug Prescriptions , Humans , Incidence , Medication Errors/statistics & numerical data , Safety ManagementABSTRACT
BACKGROUND: Medication errors are a widespread problem which can, in the worst case, cause harm to patients. Errors can be corrected if documented and evaluated as a part of quality improvement. The Danish community pharmacies are committed to recording prescription corrections, dispensing errors and dispensing near misses. This study investigated the frequency and seriousness of these errors. METHODS: 40 randomly selected Danish community pharmacies collected data for a defined period. The data included four types of written report of incidents, three of which already existed at the pharmacies: prescription correction, dispensing near misses and dispensing errors. Data for the fourth type of report, on adverse drug events, were collected through a web-based reporting system piloted for the project. RESULTS: There were 976 cases of prescription corrections, 229 cases of near misses, 203 cases of dispensing errors and 198 cases of adverse drug events. The error rate was 23/10,000 prescriptions for prescription corrections, 1/10,000 for dispensing errors and 2/10,000 for near misses. The errors that reached the patients were pooled for separate analysis. Most of these errors, and the potentially most serious ones, occurred in the transcription stage of the dispensing process. CONCLUSION: Prescribing errors were the most frequent type of error reported. Errors that reached the patients were not frequent, but most of them were potentially harmful, and the absolute number of medication errors was high, as provision of medicine is a frequent event in primary care in Denmark. Patient safety could be further improved by optimising the opportunity to learn from the incidents described.
Subject(s)
Causality , Medication Errors/statistics & numerical data , Pharmacies/standards , Denmark/epidemiology , Drug Prescriptions , Health Care Surveys , Humans , Incidence , Medical Records/standards , Medication Errors/classification , Pharmacies/statistics & numerical data , Safety Management , Systems AnalysisABSTRACT
BACKGROUND: Epidemiological studies have shown an association between gastro-oesophageal reflux disease (GORD) and asthma, and oesophageal acid perfusion may cause bronchial constriction. However, no causative relation has been proven. AIM: To assess whether acid suppression would lead to reduced asthma symptoms in children with concomitant asthma and GORD. METHODS: Thirty eight children (mean age 10.8 years, range 7.2-16.8; 29 males) with asthma and a reflux index > or =5.0 assessed by 24 hour oesophageal pH monitoring were randomised to 12 weeks of treatment with omeprazole 20 mg daily or placebo. The groups were similar in age, gender, mean reflux index, and asthma severity. Primary endpoints were asthma symptoms (daytime wheeze, symptoms at night, in the morning, and during exercise) and quality of life (PAQLQ). Secondary endpoints were changes in lung function and the use of short acting bronchodilators. At the end of the study a repeated pH study was performed to confirm the efficacy of acid suppression. RESULTS: The change in total symptom score did not differ significantly between the omeprazole and the placebo group, and decreased by 1.28 (95% CI -0.1 to 2.65) and 1.28 (95% CI -0.72 to 3.27) respectively. The PAQLQ score increased by 0.62 (95% CI 0.29 to 0.95) in the omeprazole group compared to 0.50 (95% CI 0.29 to 0.70) in the placebo group. Change in lung function and use of short acting bronchodilators were similar in the groups. The acid suppression was adequate (reflux index <5.0) under omeprazole treatment. CONCLUSION: Omeprazole treatment did not improve asthma symptoms or lung function in children with asthma and GORD.
Subject(s)
Anti-Ulcer Agents/therapeutic use , Asthma/etiology , Gastroesophageal Reflux/drug therapy , Omeprazole/therapeutic use , Adolescent , Child , Esophagus/physiopathology , Female , Gastroesophageal Reflux/complications , Humans , Hydrogen-Ion Concentration , Male , Quality of Life , Severity of Illness Index , Surveys and Questionnaires , Treatment OutcomeABSTRACT
On request of the International Criminal Tribunal for the former Yugoslavia (ICTY), the Danish-Swedish forensic teams worked in Kosovo during the summer and the fall of 1999. The teams worked mainly as "mobile teams" at sites with few graves. Only two larger sites were examined. Most of the bodies were buried separately. A few "multiple burial" graves were examined, but no mass graves were encountered. The main purpose of the autopsies was to establish the cause and manner of death. Identification was of less importance, but a majority of the bodies had been identified prior to the autopsy. A total of 308 bodies, mainly males, were examined. The age varied greatly with a mean age of 47 years. The most common cause of death was gun shot wounds and the most common manner of death was homicide.
Subject(s)
Coroners and Medical Examiners , Forensic Medicine , War Crimes/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Autopsy , Cause of Death , Child , Child, Preschool , Female , Humans , Male , Middle Aged , YugoslaviaABSTRACT
BACKGROUND: The article gives an overview of the telepathology activity at the Norwegian Radium Hospital from the service was launched in 1994 and up until today. We show the development during these years and discuss telepathology in general terms. We also discuss those aspects that determine how well a telepathology service functions. MATERIAL AND METHODS: 74 frozen section slides were diagnosed by two different telepathology systems. One of these systems was used for examining its appropriateness as a tool for second opinion in pathology. A new Internet-based system was developed that provided additional functionality. RESULTS: A telepathology system with a digital camera outperforms one with an analog camera with respect to diagnostic accuracy. INTERPRETATION: Image quality determines the precision of a telepathology service. Telepathology is a feasible tool for second opinion in pathology.
Subject(s)
Pathology Department, Hospital/organization & administration , Radiology , Telepathology/methods , Diagnosis, Computer-Assisted , Frozen Sections , Hospitals, Special/organization & administration , Humans , Image Processing, Computer-Assisted , Internet , Norway , Referral and Consultation , Remote Consultation , Telepathology/organization & administration , Telepathology/trendsABSTRACT
The carrier frequency of Asn291Ser polymorphism of the lipoprotein lipase (LPL) gene is 4;-6% in the Western population. Heterozygotes are prone to fasting hypertriglyceridemia and low high density lipoprotein (HDL) cholesterol concentrations especially when secondary factors are superimposed on the genetic defect. We studied the LPL Asn291Ser gene variant as a modulator of postprandial lipemia in heterozygote carriers. Ten normolipidemic carriers were compared to ten control subjects, who were selected to have similar age, sex, BMI, and apolipoprotein (apo)E-phenotype. The subjects were given a lipid-rich mixed meal and their insulin sensitivity was determined by euglycemic hyperinsulinemic clamp technique. The two groups had comparable fasting triglycerides and glucose utilization rate during insulin infusion, but fasting HDL cholesterol was lower in carriers (1.25 +/- 0.05 mmol/L) than in the control subjects (1. 53 +/- 0.06 mmol/L, P = 0.005). In the postprandial state the most pronounced differences were found in the very low density lipoprotein 1 (VLDL1) fraction, where the carriers displayed higher responses of apoB-48 area under the curve (AUC), apoB-100 AUC, triglyceride AUC, and retinyl ester AUC than the control subjects. The most marked differences in apoB-48 and apoB-100 concentrations were observed late in the postprandial period (9 and 12 h), demonstrating delayed clearance of triglyceride-rich particles of both hepatic and intestinal origin. Postprandially, the carriers exhibited enrichment of triglycerides in HDL fraction. Thus, in normolipidemic carriers the LPL Asn291Ser gene variant delays postprandial triglyceride, apoB-48, apoB-100, and retinyl ester metabolism in VLDL1 fraction and alters postprandial HDL composition compared to matched non-carriers.
Subject(s)
Genetic Variation , Lipoprotein Lipase/genetics , Lipoprotein Lipase/metabolism , Triglycerides/metabolism , Adult , Apolipoprotein B-100 , Apolipoprotein B-48 , Apolipoproteins B/blood , Base Sequence , Blood Glucose/metabolism , Cholesterol/blood , DNA Primers/genetics , Dietary Fats/administration & dosage , Fasting/blood , Female , Heterozygote , Humans , Insulin Resistance , Lipoproteins, VLDL/blood , Male , Triglycerides/bloodSubject(s)
Air Bags/adverse effects , Occipital Bone/injuries , Accidents, Traffic/mortality , Adult , Female , Humans , MaleABSTRACT
A procedure of making membranes of amphiphilic materials at the bottom of a U-shaped flexible plastic tube within an aqueous medium is described. The membranes were made sufficiently large in order for the annulus area to be neglected. Consequently the hydrophobic thickness of the membrane could be measured by a capacitance technique assuming the relative permittivity of the hydrophobic part of the bilayer. Introduction of an AC microvolt technique allowed manufacture of stable thick membranes by quenching the electroconstriction observed when DC electrical potentials in the millivolt range are used. By continuously monitoring the hydrophobic thickness and by use of the AC microvolt technique the membrane-thinning process by chemical means could be studied in isolation because the electroconstriction was quenched. The maximally thinned hydrophobic thickness of a monooleylglycerol membrane measured at 38 degrees C was found to be 25+/-1.2 A. Criteria and argumentation for maximal thinning of the membrane are put forward. A distinction between genuine and modified cholesterol was demonstrated to be possible by the described method.
ABSTRACT
Hypertriglyceridemia is a heterogeneous lipid disorder often running in families. Variation in the apolipoprotein B (apo B) gene has been associated with serum triglyceride levels. Recently, a role of the amino-terminal end of apo B in binding with lipoprotein lipase (LPL) has been suggested. We screened the 5' end of the apo B gene in 76 Finnish severely hypertriglyceridemic (> 6 mmol/l) patients, using a single-strand conformation polymorphism (SSCP) screening method. We detected a previously unreported polymorphic C2316-->A change, causing a Val703-->Ile substitution. The minor 703 Ile allele frequency was 0.04 in hypercholesterolemic and normolipidemic population samples. This allele was associated with lower serum triglyceride levels in a normolipidemic population sample. Analysis of two previously reported polymorphisms also located in the amino-terminal domain of apo B (Thr71-->Ile and Val591-->Ala) revealed elevating effects on serum apo B concentrations in hypertriglyceridemic individuals. The 591 Ala allele was associated with elevated apo B (P=0.011), and individuals with both minor alleles (apo B 591 Ala + and apo B 71 Ile +) had higher apo B levels compared to subjects homozygous for both common alleles (P=0.004). Although no DNA sequence change seemed to be the cause of hypertriglyceridemia in our patients, genetic variation in the 5' end of the apo B gene may contribute to changes in serum apo B levels in hypertriglyceridemic patients.