163 research outputs found
A maternal erythrocyte DHA content of approximately 6 g% is the DHA status at which intrauterine DHA biomagnifications turns into bioattenuation and postnatal infant DHA equilibrium isreached
PURPOSE: Higher long-chain polyunsaturated fatty acids (LCP) in infant compared with maternal lipids at delivery is named biomagnification. The decline of infant and maternal docosahexaenoic acid (DHA) status during lactation in Western countries suggests maternal depletion. We investigated whether biomagnification persists at lifelong high fish intakes and whether the latter prevents a postpartum decline of infant and/or maternal DHA status. METHODS: We studied 3 Tanzanian tribes with low (Maasai: 0/week), intermediate (Pare: 2â3/week), and high (Sengerema: 4â5/week) fish intakes. DHA and arachidonic acid (AA) were determined in maternal (m) and infant (i) erythrocytes (RBC) during pregnancy (1st trimester n = 14, 2nd = 103, 3rd = 88), and in motherâinfant pairs at delivery (n = 63) and at 3 months postpartum (n = 104). RESULTS: At delivery, infants of all tribes had similar iRBC-AA which was higher than, and unrelated to, mRBC-AA. Transplacental DHA biomagnification occurred up to 5.6 g% mRBC-DHA; higher mRBC-DHA was associated with âbioattenuationâ (i.e., iRBC-DHA < mRBC-DHA). Compared to delivery, mRBC-AA after 3 months was higher, while iRBC-AA was lower. mRBC-DHA after 3 months was lower, while iRBC-DHA was lower (low fish intake), equal (intermediate fish intake), and higher (high fish intake) compared to delivery. We estimated that postpartum iRBC-DHA equilibrium is reached at 5.9 g%, which corresponds to a mRBC-DHA of 6.1 g% throughout pregnancy. CONCLUSION: Uniform high iRBC-AA at delivery might indicate the importance of intrauterine infant AA status. Biomagnification reflects low maternal DHA status, and bioattenuation may prevent intrauterine competition of DHA with AA. A mRBC-DHA of about 6 g% during pregnancy predicts maternalâfetal equilibrium at delivery, postnatal iRBC-DHA equilibrium, but is unable to prevent a postnatal mRBC-DHA decline
How the data revolution can benefit farmers
Background: Iodine deficiency occurs in West European countries. Iodine is important for brain development of the foetus and infant. The current iodine status of pregnant and lactating Dutch women is unknown. Methods: In a pilot study we examined the iodine status of 36 women. From 20 gestational weeks (GW) until 4 weeks postpartum, they ingested 150 mu g iodine/day in the form of a multivitamin supplement for pregnant and lactating women. Twenty-four hour urine samples were collected at 20 and 36 GW and at 4 weeks postpartum. A breast milk sample was collected at 4 weeks postpartum. Iodine concentrations were analysed by inductively coupled plasma-mass spectrometry. Cut-off values for the urinary iodine concentration (UIC) for pregnant and lactating women are 150 and 100 mu g/l, respectively. Adequate intakes (AI) of iodine for infants aged 0-6 months are 1.1 mu mol/l (Institute of Medicine recommendations) or 0.5 mu mol/l (Nordic Council recommendations). Results: The median UICs (percentages below cut-off) were 102 mu g/l (83%) at 20 GW, 144 mu g/l (56%) at 36 GW and 112 mu g/l (40%) at 4 weeks postpartum. The median breast milk iodine concentration was 1.2 mu mol/l (range 0.5-3.0); 33% and 0% of the infants had estimated iodine intakes below the IOM-AI and Nordic-AI, respectively. Conclusion: This pilot study suggested a high prevalence of iodine deficiency during pregnancy. Daily supplementation of 150 mu g iodine from 20 GW might be insufficient to reach maternal iodine adequacy. The median breast milk iodine concentration seems adequate. Further studies, using a representative sample of the Dutch population, are needed to establish the current Dutch iodine status of pregnant and lactating women
The influence of the cultural climate of the training environment on physicians' self-perception of competence and preparedness for practice
<p>Abstract</p> <p>Background</p> <p>In current supervisory practice, the learning environment in which the training of specialist registrars (SpRs) takes place is important. Examples of such learning environments are the hospital settings and/or geographical locations where training occurs. Our objective was to investigate whether the cultural climate of different learning environments influences physicians' perceived level of competence and preparedness for practice.</p> <p>Methods</p> <p>An electronic questionnaire was sent to an equal group of paediatricians who had trained in clinical settings located in Europe and the Caribbean. 30 items (Likert scale 1â4 = totally disagree-totally agree) were used to measure the level of preparedness of the respondents in 7 physician competencies.</p> <p>Results</p> <p>42 participants were included for analysis. The distribution of participants in both groups was comparable. The overall perception of preparedness in the Caribbean group was 2.93 (SD = 0.47) and 2.86 (SD = 0.72) in the European group. The European group felt less prepared in the competency as manager 1.81 (SD = 1.06) compared to their Caribbean counterparts 2.72 (SD = 0.66). The difference was significant (p = 0.006).</p> <p>Conclusion</p> <p>The training in the different environments was perceived as adequate and comparable in effect. The learning environment's cultural climate appeared to influence the physician's perception of their competencies and preparedness for clinical practice.</p
Traditionally living populations in East Africa have a mean serum 25-hydroxyvitamin D concentration of 115 nmol/l
Cutaneous synthesis of vitamin D by exposure to UVB is the principal source of vitamin D in the human body. Our current clothing habits and reduced time spent outdoors put us at risk of many insufficiency-related diseases that are associated with calcaemic and non-calcaemic functions of vitamin D. Populations with traditional lifestyles having lifelong, year-round exposure to tropical sunlight might provide us with information on optimal vitamin D status from an evolutionary perspective. We measured the sum of serum 25-hydroxyvitamin D-2 and D-3 (25(OH) D) concentrations of thirty-five pastoral Maasai (34 (SD 10) years, 43% male) and twenty-five Hadzabe hunter-gatherers (35 (SD 12) years, 84% male) living in Tanzania. They have skin type VI, have a moderate degree of clothing, spend the major part of the day outdoors, but avoid direct exposure to sunlight when possible. Their 25(OH) D concentrations were measured by liquid chromatography-MS/MS. The mean serum 25(OH) D concentrations of Maasai and Hadzabe were 119 (range 58-167) and 109 (range 71-171) nmol/l, respectively. These concentrations were not related to age, sex or BMI. People with traditional lifestyles, living in the cradle of mankind, have a mean circulating 25(OH) D concentration of 115 nmol/l. Whether this concentration is optimal under the conditions of the current Western lifestyle is uncertain, and should as a possible target be investigated with concomitant appreciation of other important factors in Ca homeostasis that we have changed since the agricultural revolution
A phase I study of a new polyamine biosynthesis inhibitor, SAM486A, in cancer patients with solid tumours
Because tumour cell proliferation is highly dependent upon up-regulation of de-novo polyamine synthesis, inhibition of the polyamine synthesis pathway represents a potential target for anticancer therapy. SAM486A (CGP 48664) is a new inhibitor of the polyamine biosynthetic enzyme S-adenosylmethionine decarboxylase (SAMDC), more potent and specific than the first-generation SAMDC inhibitor methylglyoxal (bis) guanylhydrazone (MGBG). Preclinical testing confirmed promising antiproliferative activity. In this phase I study, SAM486A was given 4-weekly as a 120 h infusion. 39 adult cancer patients were enrolled with advanced/refractory disease not amenable to established treatments, PS †2, adequate marrow, liver, renal and cardiac function. Doses were escalated in 100% increments without toxicity in 24 pts from 3 mg mâ2cycleâ1up to 400 mg mâ2cycleâ1. At 550 and 700 mg mâ2cycleâ1reversible dose-limiting neutropenia occurred. Other toxicities included mild fatigue, nausea and vomiting. No objective remission was seen. Pharmakokinetic analysis showed a terminal half-life of approximately 2 days. AUC and Cmax were related to dose; neutropenia correlated with AUC. The recommended dose for further phase II studies on this schedule is 400 mg mâ2cycleâ1. © 2000 Cancer Research Campaig
Higher Prevalence of "Low T3 Syndrome" in Patients With Chronic Fatigue Syndrome:A Case-Control Study
Chronic fatigue syndrome (CFS) is a heterogeneous disease with unknown cause(s). CFS symptoms resemble a hypothyroid state, possibly secondary to chronic (low-grade) (metabolic) inflammation. We studied 98 CFS patients (21â69âyears, 21 males) and 99 age- and sex-matched controls (19â65âyears, 23 males). We measured parameters of thyroid function, (metabolic) inflammation, gut wall integrity and nutrients influencing thyroid function and/or inflammation. Most remarkably, CFS patients exhibited similar thyrotropin, but lower free triiodothyronine (FT3) (difference of medians 0.1%), total thyroxine (TT4) (11.9%), total triiodothyronine (TT3) (12.5%), %TT3 (4.7%), sum activity of deiodinases (14.4%), secretory capacity of the thyroid gland (14.9%), 24-h urinary iodine (27.6%), and higher % reverse T3 (rT3) (13.3%). FT3 below the reference range, consistent with the âlow T3 syndrome,â was found in 16/98 CFS patients vs. 7/99 controls (OR 2.56; 95% confidence intervalâ=â1.00â6.54). Most observations persisted in two sensitivity analyses with more stringent cutoff values for body mass index, high-sensitive C-reactive protein (hsCRP), and WBC. We found possible evidence of (chronic) low-grade metabolic inflammation (ferritin and HDL-C). FT3, TT3, TT4, and rT3 correlated positively with hsCRP in CFS patients and all subjects. TT3 and TT4 were positively related to hsCRP in controls. Low circulating T3 and the apparent shift from T3 to rT3 may reflect more severely depressed tissue T3 levels. The present findings might be in line with recent metabolomic studies pointing at a hypometabolic state. They resemble a mild form of ânon-thyroidal illness syndromeâ and âlow T3 syndromeâ experienced by a subgroup of hypothyroid patients receiving T4 monotherapy. Our study needs confirmation and extension by others. If confirmed, trials with, e.g., T3 and iodide supplements might be indicated
Brief Report: Normal Intestinal Permeability at Elevated Platelet Serotonin Levels in a Subgroup of Children with Pervasive Developmental Disorders in Curaçao (The Netherlands Antilles)
This study investigated the relationship between platelet (PLT) serotonin (5-HT) and intestinal permeability in children with pervasive developmental disorders (PDD). Differential sugar absorption and PLT 5-HT were determined in 23 children with PDD. PLT 5-HT (2.0â7.1 nmol/109 PLT) was elevated in 4/23 patients. None exhibited elevated intestinal permeability (lactulose/mannitol ratio: 0.008â0.035 mol/mol). PLT 5-HT did not correlate with intestinal permeability or GI tract complaints. PLT 5-HT correlated with 24 h urinary 5-hydroxyindoleacetic acid (5-HIAA; p = .034). Also urinary 5-HIAA and urinary 5-HT were interrelated (p = .005). A link between hyperserotonemia and increased intestinal permeability remained unsupported. Increased PLT 5-HT in PDD is likely to derive from increased PLT exposure to 5-HT. Longitudinal studies, showing the (in)consistency of abnormal intestinal permeability and PLT 5-HT, may resolve present discrepancies in the literature
- âŠ