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Contains fulltext : 238819.pdf (Publisher’s version ) (Open Access) BACKGROUND: Vitamin B12 and folate function as co-factors in pathways used during physical activity. Physical activity may therefore increase vitamin requirements, leading to a risk of deficient plasma concentrations. We aimed to investigate the relationship between intake and plasma concentrations of vitamin B12 and folate in physically active adults, as well as identify other determinants of vitamin B12 and folate plasma concentrations. METHODS: The study population consisted of 873 adults (528 men and 345 women), aged 19-78 years, who participated in a 4-day walking event. The relationship between intake and plasma concentrations of vitamin B12 and folate was assessed using correlation and linear regression analyses. In addition, potential other determinants (sex, age, body mass index, energy intake and physical activity) of vitamin plasma concentrations were investigated. RESULTS: Significant positive correlations were observed between intake and plasma concentrations of vitamin B12 [Pearson's correlation coefficient = 0.15; 95% confidence interval (CI) = 0.08-0.21] and folate (Pearson's correlation coefficient = 0.18; 95% CI = 0.12-0.25). In addition to vitamin intake, sex, age and energy intake were also determinants of both vitamin B12 and folate plasma concentrations in multivariable regression models. CONCLUSIONS: The results suggest a positive association between intake and plasma concentrations for both vitamin B12 and folate in physically active people. By contrast to our hypothesis, physical activity was not a determinant of vitamin B12 and folate plasma concentrations. However, sex, age and energy intake were found to be determinants. Thus, when studying the relationship between intake and plasma concentrations of vitamin B12 or folate, these factors should be taken into account. 01 april 2021

Background The morphological assessment of urinary erythrocytes (uRBC) is a convenient screening tool for the differentiation of nephrological (dysmorphic) and urological (isomorphic) causes of hematuria. Considering the morphological heterogeneity, this analysis is often perceived as difficult. There is no clear (inter)national consensus and there is a lack of external quality assessment programs. To gain insight into the heterogeneity within and between laboratories, we scrutinized the current state of this analysis in Dutch medical laboratories. Methods The laboratories, affiliated with the Dutch Foundation for Quality Assessment in Medical Laboratories, were invited to participate in a web-based survey, consisting of two questionnaires. The first one provided information about the institution and laboratory organization, and the second explored the variability in the morphological analysis of uRBC on the basis of categorization of 160 uRBC images. Statistical analysis was premised on binomial significance testing and principal component analysis. Results Nearly one third of the Dutch medical laboratories (65/191) with 167 staff members participated in the survey. Most of these laboratories (83%) were an integral part of secondary care. The statistical analysis of the evaluations of the participants in comparison to the consensus (three experts from two different medical laboratories) suggested a great degree of heterogeneity in the agreement. Nearly half of the participants consciously disagreed with the consensus, whereas one fifth demonstrated a random relationship with it. Conclusions In Dutch medical laboratories, results from morphological analysis of uRBC are heterogeneous, which point out the necessity for standardization and harmonization.

Purpose: Vitamin D deficiencies are common in elderly, which increases the risk for, e.g., bone fractures. Identification of determinants of vitamin D status may provide leads for specific deficiency prevention strategies. Although determinants of vitamin D status have been studied in various populations, this has not been examined in elderly that have a physically active lifestyle. Methods: Vitamin D status of 450 physically active elderly who do not use vitamin D supplements was determined and information on possible determinants (demographic, dietary intake and physical activity) was collected around a prolonged four day walking event in July and analyzed in linear regression models. Results: The average summertime serum 25(OH)D concentration was 88.8 ± 22.4 nmol/L. Only 2% of the participants had a 25(OH)D concentration below 50 nmol/L. Dietary intake of vitamin D was 4.0 ± 1.9 µg/day, and the participants spent 12.4 ± 8.6 h/week on outdoor activities. In the multivariate model, lower age (= − 0.48, 95% CI − 0.80 to − 0.16), lower BMI (= − 0.86, 95% CI − 1.62 to − 0.10), being a moderate to high drinker versus a non-drinker (= 7.97, 95% CI 0.43–15.51) and more outdoor physical activity (= 0.25, 95% CI 0.01–0.50) were significantly associated with higher 25(OH)D concentrations. Conclusions: In physically active elderly, vitamin D status was very high in summertime, with few deficiencies, suggesting that elderly with a physical active lifestyle might not necessarily need supplements during the summer period. Lower age, lower BMI, higher alcohol intake and more outdoor physical activity had a significant association with vitamin D status.

Background: Magnesium is essential for health and performance. Sub-optimal levels have been reported for older persons. In addition, physical exercise is known to temporally decrease magnesium blood concentrations. Objective: To investigate these observations in conjunction we assessed total (tMg) and ionized magnesium (iMg) concentrations in plasma and whole blood, respectively, during 4 consecutive days of exercise in very old vital adults. Design: 68 participants (age 83.7±1.9 years) were monitored on 4 consecutive days at which they walked 30–40km (average ∼8 hours) per day at a self-determined pace. Blood samples were collected one or two days prior to the start of exercise (baseline) and every walking day immediately post-exercise. Samples were analysed for tMg and iMg levels. Results: Baseline tMg and iMg levels were 0.85±0.07 and 0.47±0.07 mmol/L, respectively. iMg decreased after the first walking day (−0.10±0.09 mmol/L, p

Contains fulltext : 196745.pdf (Publisher’s version ) (Open Access) PURPOSE: The aim of the present study was to assess the effect of prolonged and repeated exercise on iron metabolism in middle-aged adults and to compare differences between sexes. METHODS: 50 male (58.9 +/- 9.9 year) and 48 female (50.9 +/- 11.2 year) individuals were monitored on 4 consecutive days at which they walked on average 8 h and 44 min per day at a self-determined pace. Blood samples were collected 1 or 2 days prior to the start of the exercise (baseline) and every day immediately post-exercise. Samples were analysed for iron, ferritin, haemoglobin, and haptoglobin concentrations. RESULTS: Plasma iron decreased across days, while ferritin increased across days (both p < 0.001). Haptoglobin showed a decrease (p < 0.001) after the first day and increased over subsequent days (p < 0.001). Haemoglobin did not change after the first day, but increased during subsequent days (p < 0.05). At baseline, 8% of the participants had iron concentrations below minimum reference value (10 micromol/L), this increased to 43% at day 4. There was an interaction between sex and exercise days on iron (p = 0.028), ferritin (p < 0.001) and haemoglobin levels (p = 0.004), but not on haptoglobin levels. CONCLUSION: This study showed decreases in iron, increases in ferritin, a decrease followed by increases in haptoglobin and no change followed by increases in haemoglobin. This is most likely explained by (foot strike) haemolysis, inflammation, and sweat and urine losses. These processes resulted in iron levels below minimum reference value in a large number of our participants.

Contains fulltext : 69498.pdf (Publisher’s version ) (Closed access) OBJECTIVE: Implementation of strict glucose control in most intensive care units has resulted in increased use of point-of-care glucose devices in the intensive care unit. The aim of this study was to determine the reliability of point-of-care testing glucose meters among critically ill patients under intensive insulin treatment. DESIGN: Prospective observational study. PATIENTS: Intensive care unit and non-intensive care unit patients in a tertiary care teaching hospital. MEASUREMENTS: A glucose oxidase method was used to validate the point-of-care testing devices. Three different point-of-care testing devices, Accu-Chek Sensor (Roche Diagnostics), Precision (Abbott Diagnostics), and HemoCue were tested. Glucose measurements were performed in duplicate by an experienced technician under standardized conditions in the hospital's laboratory, using arterial (intensive care unit patients) and arterial or venous (non-intensive care unit patients) heparinized whole blood samples. MAIN RESULTS: A strong correlation was found between the glucose oxidase method and the Accu-Chek device (r = .9596, p < 0.001). Mean absolute difference between the glucose oxidase and Accu-Chek was -0.32 mmol/L (95% confidence interval -0.84 to 1.48 mmol/L). Using the International Organization for Standardization (ISO) criteria, 27 of 197 samples (13.7%) were inaccurate. In all samples that failed to meet the ISO criteria, glucose values measured by the Accu-Chek device were higher compared with the glucose oxidase method. In another set of experiments among intensive care unit patients, strong positive correlations were also found between the other point-of-care testing devices and the glucose oxidase method. However, paired samples from Accu-Chek, HemoCue, and Precision failed the ISO criteria in 9 of 82 (11.0%), 4 of 82 (4.9%), and 11 of 82 (13.4%) of cases, respectively. In non-intensive care unit patients paired samples from Accu-Chek, HemoCue, and Precision failed the ISO criteria in 3 of 120 (2.5%), 11 of 120 (9.2%), and 16 of 120 (13.3%) cases, respectively. CONCLUSIONS: Under standardized conditions, glucose results from three point-of-care testing devices were inaccurate in both intensive care unit and non-intensive care unit patients. Among intensive care unit patients, inaccurate glucose readings were most frequently falsely elevated, resulting in misinterpretation of high glucose values with subsequent inappropriate insulin administration or masking of true hypoglycemia.

Contains fulltext : 51625.pdf (Publisher’s version ) (Open Access) CD64 is a high-affinity Fc(gamma)RI receptor expressed by activated neutrophils that has been recently evaluated as a potential sepsis parameter. In the present study, the kinetics of neutrophil membrane CD64 expression were examined during a standardized inflammatory response, using a human endotoxemia model, and compared with hematological indices, CRP, cytokines and interleukins. Ten healthy subjects received 2 ng/kg intravenous Escherichia coli lipopolysaccharide (LPS). After administration of LPS, neutrophil CD64 showed a biphasic response, characterized by a first increase from 108.5 +/- 7.5 to 133 +/- 6 AFU after 1 h (P = 0.047) and a second increase that started at 6 h and reached its maximum of 167 +/- 13 AFU at 22 h (P < 0.0001). CRP concentrations increased to 40 +/- 5 mg/dl 22 h after the administration of LPS. The cytokines and interleukins reached their maximum response within 1-2 h. The maximum values of pro-inflammatory cytokines (TNF-alpha, IFN-gamma and IL-6) correlated with the CD64 expression at 22 h after LPS administration (r(2) = 0.76, r(2) = 0.78, r(2) = 0.81, respectively, all P < 0.05), whereas this correlation was not found for the anti-inflammatory IL-10 (r(2) = 0.058, P = 0.54), suggesting that neutrophil CD64 expression might be a quantitative marker for innate immunity that could easily be used in the clinical setting.

A patient with abdominal sepsis, had both intra and extracellular bacteria in a blood smear, and high levels of neutrophil membrane CD64 and HLA-Dr. Intracellular bacteria are only observed in the terminal phase of a sepsis. Our patient recovered, suggesting that a high expression of neutrophil CD64 is indicative for a good prognosis.

Item does not contain fulltext BACKGROUND: DD3(PCA3) is the most prostate cancer-specific gene described to date. To assess the clinical utility of DD3(PCA3) a time-resolved fluorescence-based, quantitative RT-PCR analysis for DD3(PCA3) was developed. METHODS: The diagnostic potential of DD3(PCA3) was determined by quantitative measurement of DD3(PCA3) transcripts in non-malignant and malignant prostate specimens. Moreover, DD3(PCA3) transcripts were determined quantitatively in urine sediments obtained after prostatic massage. A cohort of 108 men, admitted for prostate biopsies based on a PSA of >3ng/ml, was studied. RESULTS: Prostate tumors showed a 66-fold up-regulation of DD3(PCA3) (median 158.4.10(5) copies/microg tissue RNA) when compared to benign prostate tissue (median 2.4.10(5) copies/microg tissue RNA). This up-regulation was found in more than 95% of prostate cancer specimens studied. These data revealed that specimens with less than 10% of cancer cells could be accurately discriminated from non-cancer tissues. Hence, detection of a small fraction of prostate cancer cells in a background of normal cells seemed feasible. Therefore, this DD3(PCA3)-based RT-PCR assay was used for the identification of prostate cancer in urine sediments obtained after prostatic massage. From 108 men with a serum PSA value >3ng/ml, 24 men were shown to have prostate cancer upon biopsy. Of these 24 men, 16 were shown to be positive for DD3(PCA3), indicating a sensitivity of the assay of 67%. Furthermore, a negative predictive value of 90% was calculated. CONCLUSION: The quantitative RT-PCR assay for DD3(PCA3) described, bears great promise as a tool for molecular urine analysis. It has great potential in reducing the number of unnecessary biopsies. A multi-center study using this DD3(PCA3) assay can provide the basis for the utility of molecular diagnostics in clinical urological practice.

Contains fulltext : 88944.pdf (Publisher’s version ) (Closed access) OBJECTIVE: The incidence of cerebrovascular accidents (CVA) occurring perinatally is relatively high and aspects of the multifactorial pathophysiology remain unclear. Elevated homocysteine concentrations have been shown to be associated with an increased risk for CVA in children and even in newborns. We studied the possible homocysteine lowering effect of folinic acid in newborns. METHOD: We included 37 newborns in our prospective randomized folinic acid (given as 5-formyltetrahydrofolate) intervention study from patients admitted to our neonatal intensive care unit (18 controls, 19 intervention group). We measured total homocysteine (tHcy) and plasma folate concentrations at three time points (baseline, 1 and 2 weeks after intervention). The intervention group was treated with folinic acid (70 mug/kg/day) for 2 weeks. We calculated median concentrations (25th and 75th percentiles). RESULTS: Median tHcy concentrations at the three time points did not differ from each other in the control group nor in the intervention group. We also could not observe different tHcy concentrations between both groups. Plasma folate concentrations increased in the intervention group (mean increase 167% (95% confidence interval (CI) -291, 625)) compared with control group (mean increase -12% (95% CI -132, 108)), P for treatment effect: 0.03. CONCLUSION: We could not demonstrate a homocysteine lowering effect of folinic acid administration in newborns. This indicates that one carbon metabolism in newborns differs form adults. Cobalamin might be a better strategy to lower tHcy concentrations in newborns. 01 november 2010

The PFA-100 device is increasingly used for assessing platelet function. Its use to monitor anti-platelet therapy, like acetylsalicylic acid (ASA), has been described. In most studies single PFA-100 measurements were used. In this study, we evaluate the influence of ASA on duplicate measurements using collagen/epinephrine cartridges. Twelve healthy volunteers received a single dose of 160 mg ASA and 12 other healthy volunteers received 30 mg ASA during 10 days followed by 80 mg ASA during 10 days. PFA-100 measurements were performed in duplicate 1 and 24 h after the final intake of medication. The mean coefficient of variation of duplicate measurements before medication was 8.4% and at least two times higher after the intake of a single dose of 160 mg ASA or 30 mg ASA during 10 days. Per individual, huge differences between duplicate measurements were observed after ASA ingestion. Differences were less pronounced after ingestion of 80 mg ASA during 10 days, because six of 12 volunteers had a maximum PFA-100 value > 300 s in both measurements. As a consequence, one should be cautious to use the PFA-100 to monitor ASA therapy in individual patients.

Item does not contain fulltext OBJECTIVE: To determine the incidence of troponin T elevations among a selected group of critically ill patients, to correlate these findings to electrocardiographs, and to compare troponin T-positive and T-negative patients in relation to clinical parameters. DESIGN: Prospective study. SETTING: Mixed surgical and medical intensive care unit. PATIENTS: Thirty-four consecutive critically ill patients who were mechanically ventilated or underwent thoracic or vascular surgery. INTERVENTIONS: Blood samples were collected at admission, the next morning, and 24 h after the second blood sampling. These samples were used for troponin T measurement and electrocardiographs were made when troponin T levels were elevated. MAIN RESULTS: Eleven of 34 patients (32%) had elevated troponin T levels, which were already present upon admission in eight out of 11 patients (73%). Most patients underwent surgery prior to ICU admission (21 of 34 patients). Significantly ( P=0.0055) more troponin T-positive patients underwent acute surgery, and significantly more ( P=0.045) troponin T-positive patients suffered from hypotension. Only four of the troponin T-positive patients were diagnosed as suffering from an acute myocardial infarction based on electrocardiographs. All troponin T-positive patients had coronary artery disease: nine had a history of CAD and two had actual CAD. No difference in mortality rates was observed between troponin T-positive and T-negative patients. CONCLUSIONS: An unexpectedly high percentage of included patients had troponin T elevations, which could be corroborated by electrocardiographs in only four cases suggesting that a high percentage of critically ill patients with a history of CAD suffer from clinically unrecognised (minor) myocardial damage.

The valveless scavenging circuit of Samson was compared with a standard Magill (Mapleson A) circuit. Replacement of the scavenging unit of the Samson circuit by the Heidbrink valve of the Magill circuit at a given fresh gas flow rate allowed each patient to act as his own control. The minimum and maximum carbon dioxide levels were estimated at varying fresh gas flows related to the body weight of the patient. The carbon dioxide elimination of the two circuits showed no statistical difference and it is concluded that the Samson circuit requires fresh gas flows similar to the Magill circuit. The Samson circuit scavenged adequately during spontaneous breathing, manual ventilation and even when using the emergency oxygen bypass.

Anti-Emm, an antibody to a public red cell antigen, was found in the serums of four Emm-propositi and in the serum of the Emm-brother of one of them. Three of the propositi were men, and their antibodies, as well as that of the compatible brother, were believed to be "naturally occurring." Since there are two Emm-siblings in one family, Emm is probably an inherited characteristic.

The red blood cells and sera from 21 RN/RN individuals were studied. The study confirmed the Rh type D+C+E-c-e+, CW-, characterized by an increased expression of the D antigen, a markedly decreased expression of the C and e antigens, the presence of a low incidence antigen (Rh32) and the absence of a high incidence antigen (Rh46) associated with an epitope recognized by a murine monoclonal antibody (MR 432). Four individuals exposed to Rh46 cells by pregnancy and/or transfusion had an anti-Rh46 antibody. This antibody gave positive reactions with all red blood cells of common and rare Rh phenotype except Rh null, D--, D.., DC(W-) and RN/RN cells. This antibody is considered to be of clinical significance in case of transfusion or pregnancy.