Trauma-related preventable death; data analysis and panel review at a level 1 trauma centre in Amsterdam, the Netherlands.

PURPOSE: Trauma-related death is used as a parameter to evaluate the quality of trauma care and identify cases in which mortality could have been prevented under optimal trauma care conditions. The aim of this study was to identify trauma-related preventable death (TRPD) within our institute by an external expert panel and to evaluate inter-panel reliability. METHODS: Trauma-related deaths between the 1st of January 2020 and the 1st of February 2022 at the Amsterdam University Medical Centre were identified. The severely injured patients (injury severity score ≥ 16) were enrolled for preventability analysis by an external multidisciplinary panel, consisting of a trauma surgeon, anaesthesiologist, emergency physician, neurosurgeon, and forensic physician. Case descriptions were provided, and panellists were asked to classify deaths as non-preventable, potentially preventable, and preventable. Agreements between the five observers were assessed by Fleiss kappa statistics. RESULTS: In total 95 trauma-related deaths were identified. Of which 36 fatalities were included for analysis, the mean age was 55.3 years (± 24.5), 69.4% were male and 88.9% suffered blunt trauma. The mean injury severity score was 35.3 (± 15.3). Interobserver agreement within the external panel was moderate for survivability (Fleiss kappa 0.474) but low for categorical preventable death classification (Fleiss kappa 0.298). Most of the disagreements were between non-preventable or potentially preventable with care that could have been improved. CONCLUSION: Multidisciplinary panel review has a moderate inter-observer agreement regarding survivability and low agreement regarding categorical preventable death classification. A valid definition and classification of TRPD is required to improve inter-observer agreement and quality of trauma care.

Maternal fatty acid status in pregnancy and childhood atopic manifestations: KOALA Birth Cohort Study.

BACKGROUND: Prevalence of atopic disorders has increased rapidly, but aetiological factors responsible for this increase are still largely unknown. Prenatal exposure to a pro-inflammatory fatty acid status is hypothesized although little research has been carried out. OBJECTIVE: To investigate whether prenatal fatty acid exposures are associated with atopy in childhood. METHODS: In the KOALA Birth Cohort Study, maternal blood samples (n=1275) at 34-36 weeks of pregnancy were assayed for n-6 and n-3 long-chain polyunsaturated fatty acids (LCPs). The full spectrum of offspring atopic manifestations (wheeze, asthma, allergic rhinoconjunctivitis, eczema, atopic dermatitis, allergic sensitization, and high total IgE) until the age of 6-7 years was assessed by repeated parental questionnaires and measurements of total and specific IgE. Associations of maternal fatty acid status with child atopic outcomes were analysed using multivariable logistic regression and generalized estimating equations for repeated measurements. RESULTS: High ratio of maternal n-6 vs. n-3 LCPs was associated with a lower risk of eczema in the child (P for trend 0.012). More specifically, we found a decreased risk of eczema in the first 7 months of life with increasing arachidonic acid levels (P for trend 0.013). No associations were found between maternal fatty acids and offspring airway-related atopic manifestations, sensitization, or high total IgE. CONCLUSION AND CLINICAL RELEVANCE: The development of atopic disorders in early childhood is associated with prenatal exposure to n-6 vs. n-3 fatty acids, but with inconsistencies between different manifestations. Further exploration of associations with maternal diet and genetic variants in genes regulating fatty acid metabolism are required. This study shows that the influence of prenatal exposure to fatty acids on the risk of eczema in the child is limited to the first year of life.

Serum micronutrient concentrations and childhood asthma: the PIAMA birth cohort study.

BACKGROUND: Research suggests an influence of micronutrients on childhood asthma. So far, evidence mainly originates from cross-sectional studies using nutrient intake data, which is not an accurate measure of nutrient status. This study aimed to investigate the cross-sectional and prospective associations between serum concentrations of magnesium, vitamin D, selenium, and zinc and prevalence of (severe) asthma, atopy, and bronchial hyperresponsiveness (BHR) in childhood. METHODS: In the Prevention and Incidence of Asthma and Mite Allergy birth cohort study, serum nutrient concentrations were available for a 4-yr-old subgroup (n = 372) and for a different 8-yr-old subgroup (n = 328). Yearly questionnaires inquired about asthma prevalence until 8 yr of age. Allergic sensitization was measured at 4 and 8 yr of age; BHR was measured at 8 yr of age. Data were analyzed with logistic regression and generalized estimating equations models. RESULTS: There was a consistent (non-significant) inverse association between serum magnesium concentrations and asthma prevalence. Serum vitamin D concentrations measured at age 4 were inversely associated with asthma at ages 4-8 [e.g., cross-sectional association between vitamin D tertile 3 vs. 1 and severe asthma: odds ratio (OR): 0.49, 95% confidence interval (CI): 0.25-0.95], whereas vitamin D measured at age 8 was positively associated with asthma at age 8 (e.g., cross-sectional association between vitamin D tertile 3 vs. 1 and severe asthma: OR: 2.14, 95% CI: 0.67-6.82). CONCLUSIONS: Our study contributes to the evidence that children with higher serum magnesium concentrations are less likely to have asthma. The associations between serum vitamin D concentrations and asthma were age-dependent.

Self-rated health in individuals with and without disease is associated with multiple biomarkers representing multiple biological domains.

Self-rated health (SRH) is one of the most frequently used indicators in health and social research. Its robust association with mortality in very different populations implies that it is a comprehensive measure of health status and may even reflect the condition of the human organism beyond clinical diagnoses. Yet the biological basis of SRH is poorly understood. We used data from three independent European population samples (N approx. 15,000) to investigate the associations of SRH with 150 biomolecules in blood or urine (biomarkers). Altogether 57 biomarkers representing different organ systems were associated with SRH. In almost half of the cases the association was independent of disease and physical functioning. Biomarkers weakened but did not remove the association between SRH and mortality. We propose three potential pathways through which biomarkers may be incorporated into an individual's subjective health assessment, including (1) their role in clinical diseases; (2) their association with health-related lifestyles; and (3) their potential to stimulate physical sensations through interoceptive mechanisms. Our findings indicate that SRH has a solid biological basis and it is a valid but non-specific indicator of the biological condition of the human organism.

Vitamin E supplementation during the dry period in dairy cattle. Part I: adverse effect on incidence of mastitis postpartum in a double-blind randomized field trial.

A randomized, controlled field trial with dairy cows demonstrated an adverse effect of vitamin E supplementation during the dry period on mastitis incidence in early lactation. This study was conducted on farms with historically high rates of mastitis to investigate the benefit of vitamin E supplementation on udder health; however, the outcome showed an adverse effect. The aim of the study was to evaluate whether daily supplementation of 3,000 IU of vitamin E to dairy cows during the dry period could improve udder health in commercial herds with a high incidence of mastitis. On 5 dairy farms, dry cows were randomly divided into 2 experimental groups: a high and a low group. Both groups received a dry cow mineral mix providing 3,000 or 135 IU of vitamin E/cow per day, respectively, between dry-off and calving for a mean period of 8 wk. Providing 3,000 IU of vitamin E exceeds NRC standards, but this amount has been used in previous studies. The experiment, as well as the majority of the statistical analysis, were carried out blinded. Blood was sampled 3 times before calving and on calving day. Serum was analyzed for vitamin E and cholesterol. Vitamin E and the vitamin E:cholesterol ratio were analyzed as dependent variables in mixed models and Student's t-tests to study trends in time and differences between groups. Relative risk calculation and survival analysis were used to study the effect of supplementation on mastitis incidence in the first 3 mo of lactation. The results showed that vitamin E supplements increased both absolute vitamin E and the ratio of vitamin E to cholesterol in blood. In the high group, significantly more subclinical and clinical cases occurred, showing the same trend on all farms. In this study, an initial vitamin E level at dry off above 14.5 µmol/L was a risk factor for clinical mastitis, suggesting that the vitamin E status at the start of the dry period is important. It is recommended to work out exactly at what threshold vitamin E is harmful for udder health before new trials with high dosages of vitamin E are started. Additionally, further research is required to investigate the mechanism by which vitamin E affects udder health.

Vitamin E supplementation during the dry period in dairy cattle. Part II: oxidative stress following vitamin E supplementation may increase clinical mastitis incidence postpartum.

The aim of this study was to evaluate, retrospectively, which physiological states influenced the effect of vitamin E supplements during the dry period on the level of oxidative stress at 2 wk antepartum. Furthermore the effect of oxidative stress at 2 wk antepartum on the risk of clinical mastitis in early lactation was investigated. Cows experience oxidative stress around calving. Vitamin E is able to decrease oxidative stress by scavenging free radicals. Normally, vitamin E radicals formed when vitamin E reacts with free radicals are regenerated by a network of other antioxidants, termed the "vitamin E regeneration system" (VERS). In case of vitamin E supplementation, VERS should be sufficient to regenerate formed vitamin E radicals; if not, oxidative stress might increase instead of decrease. Additionally, the level of oxidative stress and vitamin E might be important physiological states to evaluate before supplementation. In a clinical trial, 296 cows on 5 farms were randomly divided into 2 groups, supplemented with a mineral mix between dry off and calving that supplied 3,000 or 135 IU/d, respectively. Blood samples collected at dry off and 2 wk antepartum were analyzed for vitamin E, reactive oxygen metabolites, ferric-reducing ability of plasma, glutathione peroxidase, and malondialdehyde. Cows were allocated retrospectively into 8 subgroups based on the level of oxidative stress, vitamin E, and VERS status at dry off. To evaluate whether differences in physiological states at dry off influenced the effect of vitamin E supplementation on the level of oxidative stress, group effects (supplemented vs. control) were studied with Student's t-test for all 8 subgroup at 2 wk antepartum. Differences in physiological states at dry off influenced the effect of vitamin E supplements. In 2 insufficient VERS subgroups, the supplemented group had higher levels of free radicals at 2 wk antepartum compared with the control group. Relative risk calculation was used to study the effect of oxidative stress at 2 wk antepartum on the incidence of mastitis in the first 100 d of lactation. Higher levels of oxidative stress at 2 wk antepartum were related to higher risk of clinical mastitis. In conclusion, not every dry cow responded well to high vitamin E supplementation. This subgroup analysis provides a possible explanation for the unexpected adverse effects observed in the clinical trial.

Effects of vitamin E supplementation on and the association of body condition score with changes in peroxidative biomarkers and antioxidants around calving in dairy heifers.

The objective of this study was to investigate the effect of vitamin E supplementation on oxidative status in blood, liver, milk, and ovarian follicular fluid in periparturient heifers. Vitamin E supplementation started 8 wk before calving and continued until 8 wk postpartum. Grass silage was the main forage fed during the experiment. In addition, supplemented heifers (n=9) received 3,000I U of vitamin E daily on a carrier food; control heifers (n=9) consumed only the carrier food. Blood samples and liver biopsies were taken frequently throughout the study and ovarian follicular fluid was sampled at 8 wk postpartum. Body condition score was scored weekly and milk yield was measured daily. A marker of oxidative damage, determinable reactive oxygen metabolites (d-ROM), and a set of antioxidants were measured in blood, liver, milk, and ovarian follicular fluid. Control heifers had a low vitamin E status, and selenium status was marginal in control and supplemented heifers. Vitamin E supplementation increased vitamin E concentrations in blood, liver, and ovarian follicular fluid and increased triacylglycerol in liver. Serum d-ROM were not reduced by vitamin E supplementation. Superoxide dismutase and glutathione peroxidase activity in red blood cells and liver and glutathione peroxidase activity in ovarian follicular fluid were not affected by vitamin E supplementation and they were not increased around calving. Protein thiol groups and ratio of reduced glutathione to oxidized glutathione were also not increased around calving. These results suggest that heifers around calving experience a low level of oxidative processes. This might be caused by lower than expected milk production attributed to a low forage intake. Serum d-ROM were negatively correlated with protein thiol groups and positively correlated with the activity of glutathione peroxidase in red blood cells, oxidized glutathione, and the ratio of reduced glutathione and oxidized glutathione in serum. The lack of treatment effects allowed estimation of the effects of body condition 4 wk before calving and the loss of body condition on markers of lipid peroxidation and antioxidants. A trend that a body condition of >or=3 might result in more oxidative damage measured by serum d-ROM was observed, but fatter heifers had a significantly higher ratio of reduced glutathione to oxidized glutathione.

Low-grade inflammation can partly explain the association between the metabolic syndrome and either coronary artery disease or severity of peripheral arterial disease: the CODAM study.

BACKGROUND: Low-grade inflammation has been hypothesized to underlie the coronary artery disease (CAD) risk associated with the metabolic syndrome, but the evidence is not conclusive. For peripheral arterial disease (PAD; as measured by the ankle-arm index), this association has not been studied before. The aim was to study whether the association between the metabolic syndrome and CAD or the severity of PAD can be explained by low-grade inflammation. METHODS: The Cohort study Diabetes and Atherosclerosis Maastricht population includes 574 subjects, with an increased risk of type 2 diabetes, of whom 560 were included in the analyses (343 males; age: 59.5 +/- 7.0 years). The inflammation markers that were measured were C-reactive protein, interleukin 6, soluble vascular cell adhesion molecule-1, soluble intercellular adhesion molecule-1 and serum amyloid A. All analyses were adjusted for age, sex and smoking. RESULTS: Logistic regression showed that the metabolic syndrome was significantly associated with CAD [odds ratio (OR) = 1.86, 95% CI: 1.21; 2.84, P = 0.004]. Further adjustment for inflammatory status, as captured in a combination of the inflammation markers (using an averaged Z-score), resulted in significant associations of both the metabolic syndrome and inflammatory status with CAD [OR(metabolic syndrome) (95% CI) = 1.58 (1.01; 2.46), P = 0.044; OR(inflammation) (95% CI) = 1.59 (1.14; 2.21), P = 0.007]. Linear regression analysis showed similar results for the ankle-arm index. CONCLUSIONS: The association between the metabolic syndrome, on the one hand, and prevalence of CAD or the severity of PAD, on the other, can be partly but not completely, 26% and 29% respectively, explained by low-grade inflammation.

Changes in transferrin are related to changes in insulin resistance: the SLIM study.

AIMS: To determine the effect of a lifestyle intervention on serum transferrin and ferritin levels and the relationship between changes in transferrin and ferritin and changes in glucose tolerance and insulin resistance. METHODS: Randomized controlled lifestyle intervention directed at a healthy diet and increased physical activity in subjects with impaired glucose tolerance. RESULTS: After 1 year, the change in ferritin levels in the intervention group as compared with the control group did not reach statistical significance (P = 0.06). Transferrin change was independently related to the change in homeostasis model assessment of insulin resistance and ferritin change was related to the change in 2-h free fatty acids. CONCLUSIONS: Changes in insulin sensitivity and postprandial lipid metabolism are related to changes in iron metabolism.

Paraoxonase 1 phenotype distribution and activity differs in subjects with newly diagnosed Type 2 diabetes (the CODAM Study).

AIMS: Paraoxonase 1 (PON1) is an antioxidant high-density lipoprotein-bound enzyme, which was recently found to be expressed in the islets of Langerhans. A substitution (Q/R) at position 192 results in enzymes with different activity. Oxidation has been implicated in the onset of diabetes, and it can be hypothesized that PON1 may have a protective effect on diabetes. Our aim was to compare PON1 activities and PON1 Q/R phenotypes in subjects with different degrees of glucose intolerance. METHODS: We examined 566 members of the Cohort study of Diabetes and Atherosclerosis Maastricht (CoDAM), including subjects with normal glucose tolerance (NGT, n = 298), impaired glucose regulation (IGR, n = 128), newly diagnosed Type 2 diabetes (nDM, n = 78) and treated, that is to say known, Type 2 diabetes (kDM, n = 64). PON1 activity was measured in serum using paraoxon and diazoxon as substrates. The PON1 phenotype was determined using two-dimensional enzyme analysis. RESULTS: The RR-phenotype was significantly more frequent in nDM compared with NGT subjects (14.1 vs. 6.0%, P = 0.05). Adjusted for the PON1 phenotype, subjects with nDM had significant lower PON1 activity towards paraoxon and diazoxon than subjects with NGT. Adjusted odds ratios comparing the RR-variant with the QQ-variant were 2.17 [95% confidence interval (CI): 0.90-5.24] for impaired glucose tolerance, 2.84 (95% CI: 1.03-7.83) for nDM, 2.13 (95% CI; 0.61-7.42) for kDM and 2.65 (95% CI: 1.10-6.40) for total diabetes mellitus. CONCLUSIONS: An aberrant PON1 phenotype distribution and PON1 activity were observed in early diabetes. In addition, the higher state of oxidative stress may affect the future development of complications.

Short-term beta-adrenergic regulation of leptin, adiponectin and interleukin-6 secretion in vivo in lean and obese subjects.

AIM: Adipose tissue and skeletal muscle are endocrine organs, secreting substances that have been implicated in obesity-related disorders. This study examined short-term beta-adrenergic regulation of circulating leptin, adiponectin and interleukin-6 (IL-6) concentrations and secretion from abdominal subcutaneous adipose tissue and muscle (IL-6) in vivo in lean and obese subjects. METHODS: Systemic concentrations and net fluxes of leptin, adiponectin and IL-6 across abdominal subcutaneous adipose tissue and forearm skeletal muscle (IL-6) were assessed before and during beta-adrenergic stimulation (intravenous isoprenaline infusion) in 13 lean and 10 obese men. RESULTS: Basal circulating leptin concentrations were higher in the obese (p < 0.001), while circulating adiponectin (p = 0.45) and IL-6 concentrations (p = 0.41) were not different between groups. beta-Adrenergic stimulation decreased leptin concentrations in both groups (p < 0.01), but did not reduce net abdominal subcutaneous adipose tissue leptin release. Increased leptin clearance and/or decreased leptin secretion from other fat depots may explain the reduction in leptin concentrations. Adiponectin concentrations remained unchanged during beta-adrenergic stimulation in both groups. beta-Adrenergic stimulation increased IL-6 concentration, which was more pronounced in the obese (p = 0.01 vs. lean). This cannot be explained by increased IL-6 release per unit abdominal subcutaneous adipose tissue and muscle but might be because of the increased fat mass and fat-free mass at whole-body level. CONCLUSIONS: Short-term beta-adrenergic stimulation decreases leptin concentrations, which cannot be explained by reduced net leptin release from abdominal subcutaneous adipose tissue, while it elevates IL-6 concentration partly by increased release from this fat depot and muscle. Finally, beta-adrenergic stimulation has no short-term regulatory role in adiponectin secretion.

Effects of rosuvastatin on postprandial leukocytes in mildly hyperlipidemic patients with premature coronary sclerosis.

We investigated whether pro-inflammatory aspects of the postprandial phase can be modulated by rosuvastatin in premature coronary artery disease (CAD) patients. Herefore standardized 8 h oral fat loading tests were performed off-treatment and after rosuvastatin 40 mg/d in 20 male CAD patients (50 +/- 4 years). The expression of leukocyte activation markers CD11a, CD11b, CD62L and CD66b was studied using flowcytometry. Migration of isolated neutrophils towards chemoattractants was determined in a fluorescence-based assay. Rosuvastatin did not affect baseline leukocyte counts nor the postprandial neutrophil increment (maximum mean increase +10% pre- and +14% post-treatment, P < 0.01 for each). Rosuvastatin reduced baseline platelets (from 266 +/- 78 to 225 +/- 74 x 10(9) cells/L, P < 0.001) and blunted the postprandial platelet count change (maximum mean increase +6%, P = 0.01, and 0%, respectively). The baseline expression of CD11a, CD11b and CD62L increased on most types of leukocytes by rosuvastatin, whereas the postprandial responses were unaffected. Pretreatment, postprandial neutrophil migration increased dose-dependently, but there were no postprandial changes after rosuvastatin. The latter effect was unrelated to changes in lipoprotein concentrations. In conclusion, in CAD patients postprandial pro-inflammatory and pro-coagulant changes can be modified by rosuvastatin. These apparently lipid-lowering independent effects may render protection against atherosclerosis.

The use of affinity matrices in the purification of inhibin from bovine follicular fluid.

The protein associated with inhibin-like activity in bovine follicular fluid was purified 80- to 120-fold after successive adsorptions on different affinity matrices, i.e. Matrex gel red A, phenyl sepharose, omega-aminohexyl agarose and concanavalin-A sepharose. Partial characterization of the active protein resulted in the conclusion that inhibin from bovine follicular fluid is a hydrophobic glycoprotein with an apparent molecular weight between 60 000 and 70 000 daltons. An antiserum, raised against an 80-fold purified preparation, prevented the inhibin-like action of bovine follicular fluid on pituitary cells in vitro.

Hypergastrinaemia during long-term omeprazole therapy: influences of vagal nerve function, gastric emptying and Helicobacter pylori infection.

AIM: elucidate the mechanisms that lead to severe hypergastrinaemia during long-term omeprazole therapy for gastro-oesophageal reflux disease (GERD). PATIENTS AND METHODS: A total of 26 GERD patients were studied during omeprazole maintenance therapy. Twelve patients with severe hypergastrinaemia (gastrin > 400 ng/L) were compared with 14 control patients (gastrin < 300 ng/L). Helicobacter pylori serology and a laboratory screen were obtained in all patients. Gastric emptying was scored by the evidence of food remnants upon endoscopy 12 h after a standardized meal. Gastric antrum and corpus biopsies were analysed for histological parameters, as well as somatostatin and gastrin concentrations. All patients underwent a meal-stimulated gastrin test and the hypergastrinaemia patients also underwent a vagal nerve integrity assessment by pancreatic polypeptide testing (PPT). RESULTS: Severe hypergastrinaemia patients had a longer duration of treatment (80 vs. 55 months; P = 0.047) and were characterized by a higher prevalence of H. pylori infection (9/12 vs. 2/14, P = 0.004), corpus mucosal inflammation and atrophic gastritis (P < 0.04). This was reflected in lower serum pepsinogen A concentrations (mean +/- S.E.M. 53.6 +/- 17.9 vs. 137 +/- 16.0 mg/L, P = 0.03), pepsinogen A/C ratio (1.8 +/- 0.3 vs. 4.1 +/- 0.6, P = 0.005) and mucosal somatostatin concentrations (2.75 +/- 0.60 vs. 4.48 +/- 1.08 mg/g protein, P = 0.038). Two patients in the hypergastrinaemia group had signs of delayed gastric emptying, but none in the normogastrinaemia group did (P = N.S.). In addition, both groups had a normal meal-stimulated gastrin response. CONCLUSION: Severe hypergastrinaemia during omeprazole maintenance therapy for GERD is associated with the duration of therapy and H. pylori infection, but not with abnormalities of gastric emptying or vagal nerve integrity.

Polymorphism Ncol in tumor necrosis factor B is associated with fasting glycemia and lipid parameters in healthy non-obese caucasian subjects.

BACKGROUND: The study was designed to investigate the associations among polymorphisms TNF-B Ncol and TNF-alpha -308G/A, plasma TNF-alpha levels and metabolic and anthropometric parameters related to insulin sensitivity in a set of 113 Caucasian subjects undergoing oral glucose tolerance test (oGTT). METHODS: Genotypes were detected by PCR; BMI, WHR, glycemia during oGTT, fasting immunoreactive insulin, fasting C-peptide, HbA(1c), total cholesterol, triglycerides, HDL, LDL and plasma TNF-alpha levels were measured in each subject. RESULTS: Type 2 diabetes was diagnosed in 10 subjects, impaired glucose tolerance (IGT) in 41, normal glucose tolerance (NGT) in 62. Significant differences among genotypes of the TNF-B Ncol were observed for FPG (P=0.0063), LDL (P=0.0179) and marginally for total cholesterol (P=0.0763) in NGT group. After the classification of NGT subjects into obese and non-obese according to BMI, associations of TNF-B Ncol with FPG, LDL and cholesterol were proved in non-obese subgroup only. TNF-alpha -308G/A polymorphism was not associated with any of the parameters studied. TNF-alpha levels did not revealed difference among NGT, IGT and DM groups or genotype-dependent differences. CONCLUSIONS: Our results indicate significant association of the TNF-B Ncol polymorphism with FPG, LDL and total cholesterol in normoglycemic non-obese Caucasian subjects. This polymorphism could be involved in genetic modulation of glucose and lipid homeostasis and regulation of insulin sensitivity already in healthy state. Disturbances of this regulation could be component of pathogenesis of type 2 diabetes mellitus.

Rheumatoid vasculitis presenting as appendicitis.

Appendicitis was diagnosed in a 38-year-old patient with seropositive rheumatoid arthritis. Despite appendectomy the patient's clinical condition deteriorated. Thorough microscopical evaluation of the pathological anatomical specimens from the appendix made possible a diagnosis of necrotizing vasculitis. The systemic nature of the vasculitis was confirmed with a muscle biopsy. A complete remission was induced with immunosuppressive treatment. The case exemplifies a rare but serious manifestation of rheumatoid vasculitis.

Relations among serum ferritin, C282Y and H63D mutations in the HFE gene and type 2 diabetes mellitus in the Czech population.

Aims of the study were: (i) to determine the prevalence of mutations C282Y and H63D in the HFE gene causing hereditary hemochromatosis in patients with type 2 diabetes mellitus and non-diabetics, (ii) to investigate the relationship among HFE genotypes, serum ferritin and glucose intolerance and (iii) to assess possible association of HFE mutations with the susceptibility to develop late diabetic complications in the Czech population. Two approaches were employed - the case-control study comprising diabetics and non-diabetic controls (n = 326) and the cross-sectional study comprising subjects with a previously unknown defect of glucose tolerance (n = 113, oral glucose tolerance test performed in each subject). Allele frequencies of C282Y and H63D did not differ between diabetic and control groups nor among subjects with normal glucose tolerance (NGT), impaired glucose tolerance (IGT) and diabetes. Ferritin levels significantly differed between diabetic and non-diabetic women (P<1.10 (-3)) and among subjects with NGT, IGT and diabetes (P<0.05). Differences in ferritin levels related to particular genotypes of C282Y and H63D were not detected. Prevalence of diabetes in the first and second quartiles of ferritin distribution differed highly significantly from the prevalence in the third and fourth quartiles in women (P = 0.000037), OR = 3.50 (95% CI, 1.89-6.48). The extent of diabetic late complications did not correlate with ferritin plasma levels.

A new physiological biomarker for nitrate exposure in humans.

After toxicological studies with nitrate/nitrite in rats it was observed with nuclear magnetic resonance that N-methylnicotinamide (NMN), a metabolite of tryptophan was increased. The use of NMN as a biomarker for nitrate/nitrite exposure was investigated further in additional experiments with rats and in a human study with volunteers. Rats have been exposed to 36 mmol KCl, KNO2 or KNO3 per 1 tap water for 13 weeks. In general, the animals receiving KNO2 showed a statistically significant (P < 0.01) 2-fold increase in NMN compared with the KCl group. This increase was observed after a relatively high exposure (about 800 mg/kg body wt./day). It was also noticed that the initial increase in urinary NMN concentrations decreased after prolonged exposure for 12 weeks. To investigate the induction of urinary NMN in humans, an experiment has been performed in which 8 volunteers received a single oral dose of sodium nitrate, corresponding with 10 mg NaNO3/kg body wt./day (2 times the acceptable daily intake for nitrate). A rapid increase of urinary NMN (up to 6-fold) was observed in 4 volunteers. In the other 4 volunteers the urinary NMN concentration did hardly react. When the experiment was repeated with the same volunteers, it was remarkable to see that in this experiment all volunteers showed the same individual response on urinary NMN as in the first experiment. It is concluded that NMN can possibly be a good biomarker for the internal nitrite exposure of humans, but further studies are necessary to assess its value.

Effective control for diethylstilbestrol in cattle in the Netherlands.

In the period from August 1981 to April 1983, 10243 random samples of urine from slaughtered cattle were inspected for the presence of the stilbene derivatives diethylstilbestrol (DES), dienestrol (DE), and hexestrol (HEX). Fast screening of all samples was performed by radioimmunoassay (RIA) with prior clean-up column chromatography. In this screening, 216 samples were indicated for confirmatory analyses by combined high performance liquid chromatography-gas chromatography-mass spectrometry (HPLC-GCMS) on account of an immunochemical response equivalent to 1 microgram/1 DES or more. The presence of DES was confirmed in 184 samples, DE in 5 samples and HEX in 14 samples. In the remaining 13 samples no stilbene derivative could be confirmed. From the results in 1984, after the introduction of the Meat Inspection Act, it is concluded that the use of stilbene derivatives in cattle in the Netherlands has dropped almost to zero. Of 4558 samples investigated, only 6 (0.13%) were indicated as 'stilbene' positive. The presence of DES was confirmed in 2 samples and DE in 4 samples.

Monitoring and identification of residues of anabolic preparations in slaughtered cattle by HPLC with diode array detection.

The new combination of isocratic high performance liquid chromatography (HPLC) with on line UV spectrum detection via a diode array configuration has been applied to the detection and identification of anabolics present in application sites of cattle. Combination of the characteristic retention time in the HPLC chromatogram and a comparison of the full spectrum between 190-400 nm of the anabolic components with that of a standard resulted in a very reliable identification. By means of this method 117 samples of application sites were investigated for the presence of anabolic residues. Of the xenobiotic anabolics , 19-nortestosterone (NT) was found most frequently (in 96 cases), whereas diethylstilbestrol (DES) was found in only 11 cases. In all samples the identification of NT and DES was confirmed by high resolution gas chromatography-mass spectrometry (GCMS).