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Commonly recommended daily intake of vitamin D is not sufficient if sunlight exposure is limited 总被引:9,自引:0,他引:9
Glerup H Mikkelsen K Poulsen L Hass E Overbeck S Thomsen J Charles P Eriksen EF 《Journal of internal medicine》2000,247(2):260-268
OBJECTIVES: Sunlight exposure of the skin is known to be the most important source of vitamin D. The aims of this study were: (i) to estimate vitamin D status amongst sunlight-deprived individuals (veiled Arab women, veiled ethnic Danish Moslem women and Danish controls); and (ii) through food intake analysis to estimate the oral intake of vitamin D necessary to keep a normal vitamin D status in sunlight-deprived individuals. DESIGN: Cross-sectional study amongst randomly selected Moslem women of Arab origin living in Denmark. Age-matched Danish women were included as controls. To control for racial differences, a group of veiled ethnic Danish Moslem women (all Caucasians) was included. SETTING: Primary Health Care Centre, City Vest and Department of Endocrinology and Metabolism C, University Hospital of Aarhus, Aarhus Amtssygehus, Aarhus, Denmark. SUBJECTS: Sixty-nine Arab women (60 veiled, nine non-veiled) and 44 age-matched Danish controls were randomly selected amongst patients contacting the primary health care centre for reasons other than vitamin D deficiency. Ten ethnic Danish Moslem women were included through a direct contact with their community. MAIN OUTCOME MEASURES: Serum levels of 25-hydroxyvitamin D were used as estimates of vitamin D status. Intact parathyroid hormone (PTH) was used to control for secondary hyperparathyroidism. Alkaline phosphatase and bone-specific alkaline phosphatase were used as markers for osteomalacic bone involvement. Oral intake of vitamin D and calcium were estimated through a historical food intake interview performed by a trained clinical dietician. RESULTS: Veiled Arab women displayed extremely low values of 25-hydroxyvitamin D: 7.1 +/- 1.1 nmol L-1, compared with 17.5 +/- 2. 3 (P < 0.002) in ethnic Danish Moslems and 47.1 +/- 4.6 (P < 10-17) in Danish controls. PTH was increased amongst veiled Arab women: 15. 6 +/- 1.8 pmol L-1, compared with 5.7 +/- 1.4 in ethnic Danish Moslems and 2.7 +/- 0.3 (P < 10-6) in Danish controls. The vitamin D intake (including food supplementation) was very low amongst Arab women: 1.04 microg day-1, compared with 13.53 amongst ethnic Danish Moslems and 7.49 amongst Danish controls (P < 0.0005). CONCLUSIONS: Severe vitamin D deficiency is prevalent amongst sunlight-deprived individuals living in Denmark. In veiled Arab women, vitamin D deficiency is the result of a combination of limitations in sunlight exposure and a low oral intake of vitamin D. The oral intake of vitamin D amongst veiled ethnic Danish Moslems was, however, very high, at 13.53 microgram (approximately 600 IU), but they were still vitamin D-deficient. Our results suggest that the daily oral intake of vitamin D in sunlight-deprived individuals should exceed 600 IU; most probably it should be 1000 IU day-1 to secure a normal level of 25-hydroxyvitamin D. This finding is in contrast with the commonly used RDA (recommended daily allowance) for adults in Europe: 200 IU day-1. 相似文献
44.
Rui Shen Ong Diana C. Kappatos Sarah G.G. Russell Helen A. Poulsen Samuel D. Banister Roy R. Gerona Michelle Glass Cameron S. Johnson Mary‐Jane McCarthy 《Drug testing and analysis》2020,12(2):195-214
We describe the validation of a method for the simultaneous analysis of 29 synthetic cannabinoids (SCs) and metabolites, 4 amphetamines, and 2 cannabinoids in human whole blood. This method enables one analysis to cover what previously required multiple analyses for these classic and novel drugs‐of‐abuse with diverse physicochemical properties. The scope of targeted analytes was based on the most prevalent drugs‐of‐abuse and SCs encountered at the New Zealand border in 2017 and included parent compounds and metabolites belonging to the indole and indazole carboxamide, quinolinyl indole carboxylate, and naphthoylindole classifications. Samples were prepared by supported‐liquid‐extraction (SLE) followed by liquid chromatography?tandem mass spectrometry (LC?MS/MS) analysis with positive electrospray ionization (ESI). The method was validated with respect to selectivity, matrix effects, process efficiency, sensitivity, repeatability, extract stability, and carryover for qualitative confirmation. Linearity as well as accuracy and precision data at target decision concentrations were also evaluated. The limits of detection and confirmation ranged from 0.1 to 6.0 ng/mL and 1.0 to 6.0 ng/mL, respectively. The described method was successfully applied to the analysis of 564 ante‐ and post‐mortem blood samples in 2018. There were 132 cases (23%) with positive findings of at least one SC, with the five most commonly detected SCs being AMB‐FUBINACA and/or acid (61%), 5F‐ADB and/or acid (40%), ADB‐FUBINACA (11%), 5F‐MDMB‐PICA acid (6%), and MDMB‐FUBINACA acid (6%). The results also demonstrate the predominant presence of metabolites at higher levels than the unchanged parent SCs in blood, highlighting the need to maintain forensic screening methods capable of the simultaneous detection of both parent compounds and metabolites. 相似文献
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46.
Resveratrol reduces the levels of circulating androgen precursors but has no effect on,testosterone, dihydrotestosterone,PSA levels or prostate volume. A 4‐month randomised trial in middle‐aged men 下载免费PDF全文
47.
The long‐term influence of repetitive cellular cardiac rejections on left ventricular longitudinal myocardial deformation in heart transplant recipients 下载免费PDF全文
Tor Skibsted Clemmensen Brian Bridal Løgstrup Hans Eiskjær Søren Høyer Steen Hvitfeldt Poulsen 《Transplant international》2015,28(4):475-484
The aim of the study was to evaluate the long‐term influence of repeated acute cellular rejections on left ventricular longitudinal deformation in heart transplantation (HTX) patients. One hundred and seventy‐eight HTX patients were included in the study. Rejections were classified according to the International Society of Heart and Lung Transplantation (ISHLT) classification (0R–3R). Patients were divided into three groups according to rejection scores (RSs). Group 1: <50% of biopsies with 1R rejection and no ≥2R rejections; Group 2: ≥50% of biopsies with 1R rejection or one biopsy with ≥2R rejection; Group 3: ≥Two biopsies with ≥2R rejections. All patients had a comprehensive echocardiographic examination and coronary angiography. We found significantly decreasing global longitudinal strain (GLS) comparing to rejection groups (GLS group 1: ?16.8 ± 2.4 (%); GLS group 2: ?15.9 ± 3.3 (%); GLS group 3: ?14.5 ± 2.9 (%), P = 0.0003). After excluding patients with LVEF < 50% or vasculopathy, GLS was still significantly reduced according to RS groups (P = 0.0096). Total number of 1R and 2R rejections correlated significant to GLS in a linear regression model. In contrast, we found fractional shortening and LVEF to be unaffected by repeated rejections. In conclusion, repeated cardiac rejections lead to impaired graft function as detected by decreasing magnitude of GLS. In contrast, traditional systolic graft function surveillance by LVEF did not correlate to rejection burden. 相似文献
48.
The localization, release, and effects of substance P and neurokinin A were studied in the porcine pancreas and the localization of substance P immunoreactive nerve fibers was examined by immunohistochemistry. The effects of electrical vagus stimulation and capsaicin infusion on tachykinin release and the effects of substance P and neurokinin A infusion on insulin, glucagon, somatostatin, and exocrine secretion were studied using the isolated perfused porcine pancreas with intact vagal innervation. NK-1 and NK-2 receptor antagonists were used to investigate receptor involvement. Substance P immunoreactive nerve fibers were localized to islets of Langerhans, acini, ducts, and blood vessels. Vagus stimulation had no effect on substance P and neurokinin A release, whereas capsaicin infusion stimulated release of both. Substance P and neurokinin A infusion increased release of insulin, glucagon, and exocrine secretion, whereas somatostatin secretion was unaffected. The effect of substance P on insulin, glucagon, and exocrine secretion was blocked by the NK-1 receptor antagonist. The effect of electrical stimulation of vagus nerves on insulin and exocrine secretion was not influenced by tachykinin receptor antagonists. We conclude that tachykinins stimulate both endocrine and exocrine pancreatic functions through NK-1 receptors. Tachykinins are not involved in vagal regulation of pancreatic secretion in pigs but could constitute part of an alternative stimulatory system. 相似文献
49.
Kofoed PE Alfrangis M Poulsen A Rodrigues A Gjedde SB Rønn A Rombo L 《Tropical medicine & international health : TM & IH》2004,9(1):171-177
The antifolate drugs sulphadoxine and pyrimethamine are used for treatment of chloroquine-resistant Plasmodium falciparum in Africa. Resistance to pyrimethamine has been associated with point mutations in the dhfr-gene and resistance to sulphadoxine with mutations in the dhps-gene. There is concern that the use of the antifolates trimethoprim and sulphamethoxazole for treatment of other infectious diseases will result in the selection of malaria parasites with mutations in these genes. In Guinea-Bissau, where sulfonamide and trimethoprim-containing drugs have been used extensively, we decided to assess the prevalence of mutations in the dhfr-and dhps-gene in P. falciparum isolated from children suffering from acute malaria and to assess the resistance patterns to trimethoprim/sulphamethoxazole in Escherichia coli isolated from the same patients. A thick film and a blood sample for polymerase chain reaction (PCR) were obtained from 100 children attending the Bandim Health Centre in Bissau with symptoms compatible with malaria. Furthermore, a stool sample was collected from the same children and cultured for E. coli. Of the cultured E. coli, 67% were resistant both to sulfonamides and trimethoprim, 4% to sulfonamides alone, 3% to trimethoprim alone while 26% were fully sensitive to both drugs. PCR was successfully performed in 97 blood samples. Of these, 41% had triple mutations at the dhfr-gene (at codons 51, 59 and 108), and 15% had triple mutations plus mutation at codon 437 in the dhps-gene. Only 45% harboured the wild-type dhfr-gene. Thus both bacterial resistance and mutations in the parasitic genes were common, but not linked in the individual child. As sulphadoxine-pyrimethamine has only been used as a second line treatment for chloroquine resistant malaria in Guinea-Bissau for a few years, it is worrying to find a high prevalence of mutations in the parasitic genes coding for resistance to these drugs. Therefore, restricting the use of sulphadoxine-pyrimethamine for the treatment of chloroquine resistant malaria might not be sufficient to prevent the development of resistance in the parasites as long as antifolate drugs are used extensively. 相似文献
50.
Secretion of goblet cell serine proteinase, ingobsin, is stimulated by vasoactive intestinal polypeptide and acetylcholine 总被引:1,自引:0,他引:1
Ingobsin is localized to the intestinal goblet cells in the rat and in man. In the present study, we investigated the effect of vasoactive intestinal polypeptide (VIP) and acetylcholine on the secretion of ingobsin from the proximal duodenum. Intravenous infusion of VIP or acetylcholine increased the concentration of ingobsin in duodenal secretion, while the concentration in the duodenum was unchanged. Simultaneous infusion of VIP and acetylcholine increased the concentration of ingobsin in duodenal secretion and decreased the concentration of ingobsin in the duodenum. This study demonstrates that secretion of ingobsin from the proximal duodenum is exocrine and can be stimulated by VIP and acetylcholine. 相似文献