scholarly journals Vitamin D deficiency and metabolic syndrome in elderly Chinese individuals: evidence from CLHLS

2020 ◽  
Author(s):  
Ling Liu ◽  
Zhaojin Cao ◽  
Feng Lu ◽  
Yingchun Liu ◽  
Yuebin Lv ◽  
...  
Keyword(s):  
Metabolic Syndrome ◽  
Vitamin D ◽  
Waist Circumference ◽  
Vitamin D Deficiency ◽  
Elderly People ◽  
Serum Vitamin ◽  
Serum Vitamin D ◽  
Vitamin D Levels ◽  
Elderly Chinese ◽  
25 Hydroxy Vitamin D

Abstract Objectives : Both low vitamin D status and metabolic syndrome (MetS) are worldwide concerns, and low vitamin D levels are associated with MetS; however, related epidemiological evidence based on elderly Chinese individuals, especially those over 80 years of age, is limited. In the present study, we aimed to evaluate the association between serum 25-hydroxy vitamin D and MetS in elderly Chinese individuals. Method: Serum 25-hydroxy vitamin D (25(OH)D3) was measured in a cross-sectional sample of 2493 elderly people aged 65-112 years from eight areas of China in which the density of centenarians is exceptionally high. MetS was diagnosed according to blood pressure, lipid, and blood sugar levels; waist circumference; and body mass index (BMI). Adjusted multivariable logistic regression was used to analyze the associations between vitamin D and MetS based on different diagnostic criteria. Results: A total of 890 (35.7%) of the recruited elderly individuals had insufficient levels of vitamin D, and 1029 participants (41.3%) were vitamin D deficient. High serum vitamin D concentrations were associated with a low prevalence of MetS according to the modified Adult Treatment Panel III (ATP III) criteria for adequate versus deficient vitamin D levels (OR: 0.63, 95% CI: 0.45, 0.88) and inadequate versus deficient vitamin D levels (OR: 0.70, 95% CI: 0.52, 0.92). Each 10 ng/ml increase in serum vitamin D was significantly associated with a decreased prevalence of MetS according to the modified ATP III criteria for people with normal waist circumference (WC) (OR: 0.55, 95% CI: 0.43,0.71). However, no significant statistical correlation was found among elderly people with a high WC. Additionally, in the analysis of the individual components, the ORs of adequate versus deficient vitamin D levels were 0.46 (95% CI: 0.30, 0.71) for elevated triglycerides and 0.64 (95% CI: 0.42, 0.97) for reduced high-density lipoprotein cholesterol (HDL-C) after adjustment for other components. Conclusions: Vitamin D deficiency is very common among elderly Chinese individuals. Vitamin D deficiency may be a risk factor for MetS; however, the association was only statistically significant among elderly people with noncentral obesity. Further studies are needed to examine the causal direction of the association.

scholarly journals Vitamin D deficiency and metabolic syndrome in elderly Chinese individuals: evidence from CLHLS

2020 ◽  
Author(s):  
Ling Liu ◽  
Zhaojin Cao ◽  
Feng Lu ◽  
Yingchun Liu ◽  
Yuebin Lv ◽  
...  
Keyword(s):  
Metabolic Syndrome ◽  
Vitamin D ◽  
Waist Circumference ◽  
Vitamin D Deficiency ◽  
Elderly People ◽  
Serum Vitamin ◽  
Serum Vitamin D ◽  
Vitamin D Levels ◽  
Elderly Chinese ◽  
25 Hydroxy Vitamin D

Abstract Objectives : Both low vitamin D status and metabolic syndrome (MetS) are worldwide concerns, and low vitamin D levels are associated with MetS; however, related epidemiological evidence based on elderly Chinese individuals, especially those over 80 years of age, is limited. In the present study, we aimed to evaluate the association between serum 25-hydroxy vitamin D and MetS in elderly Chinese individuals. Method: Serum 25-hydroxy vitamin D (25(OH)D3) was measured in a cross-sectional sample of 2493 elderly people aged 65-112 years from eight areas of China in which the density of centenarians is exceptionally high. MetS was diagnosed according to blood pressure, lipid, and blood sugar levels; waist circumference; and body mass index (BMI). Adjusted multivariable logistic regression was used to analyze the associations between vitamin D and MetS based on different diagnostic criteria. Results: A total of 890 (35.7%) of the recruited elderly individuals had insufficient levels of vitamin D, and 1029 participants (41.3%) were vitamin D deficient. High serum vitamin D concentrations were associated with a low prevalence of MetS according to the modified Adult Treatment Panel III (ATP III) criteria for adequate versus deficient vitamin D levels (OR: 0.63, 95% CI: 0.45, 0.88) and inadequate versus deficient vitamin D levels (OR: 0.70, 95% CI: 0.52, 0.92). Each 10 ng/ml increase in serum vitamin D was significantly associated with a decreased prevalence of MetS according to the modified ATP III criteria for people with normal waist circumference (WC) (OR: 0.55, 95% CI: 0.43,0.71). However, no significant statistical correlation was found among elderly people with a high WC. Additionally, in the analysis of the individual components, the ORs of adequate versus deficient vitamin D levels were 0.46 (95% CI: 0.30, 0.71) for elevated triglycerides and 0.64 (95% CI: 0.42, 0.97) for reduced high-density lipoprotein cholesterol (HDL-C) after adjustment for other components. Conclusions: Vitamin D deficiency is very common among elderly Chinese individuals. Vitamin D deficiency may be a risk factor for MetS; however, the association was only statistically significant among elderly people with noncentral obesity. Further studies are needed to examine the causal direction of the association.

scholarly journals Assessment of Relationship Between Serum Vitamin D Levels and Metabolic Syndrome Components in Hemodialysis Patients

2021 ◽  
Vol 28 (1) ◽  
pp. E202113
Author(s):  
Sevil Karahan Yılmaz ◽  
Cuma Mertoğlu ◽  
Aylin Ayaz
Keyword(s):  
Metabolic Syndrome ◽  
Vitamin D ◽  
Vitamin D Deficiency ◽  
Serum Vitamin ◽  
Vitamin D Insufficiency ◽  
Hemodialysis Patients ◽  
Hydroxyvitamin D ◽  
Serum Vitamin D ◽  
Vitamin D Levels ◽  
25 Oh Vitamin D

Aim: This study is aimed to evaluate the relationship between serum vitamin D levels and metabolic syndrome in hemodialysis patients. Materials and Methods: This study was conducted with participation of 80 patients undergoing hemodialysis for more than 6 months three times a week, aged > 18 years. Their height, dry weight, waist circumference were measured. Biochemical parameters such as serum 25-hydroxyvitamin D, lipid profile, and fasting blood glucose were analyzed. Metabolic syndrome was defined using the National Cholesterol Education Program Adult Treatment Panel III criteria. Severe vitamin D deficiency, 25 (OH) vitamin D < 5 ng/ml; mild vitamin D deficiency, 25 (OH) vitamin D 5-15 ng/ml; vitamin D insufficiency, 25 (OH) vitamin D 16-30 ng/ml, and vitamin D sufficiency, 25 (OH) vitamin D > 30 ng/ml were categorized. Statistical analysis of the data was performed with the use of SPSS version 21.0. Results: 48.4% of hemodialysis patients were identified to have metabolic syndrome. According to the serum levels of vitamin D; 35.0% of patients had severe vitamin D deficiency, 37.4% of patients had mild vitamin D deficiency, 18.8% of patients had vitamin D insufficiency and 8.8% of patients had vitamin D sufficiency (> 30 ng/ml). Vitamin D insufficiency was significantly associated with metabolic syndrome and central obesity. Conclusions: Deficiency/insufficiency is observed in serum 25-hydroxyvitamin D levels in hemodialysis patients. Vitamin D insufficiency is associated with metabolic syndrome.

Genetic Variation in CYP2R1 and GC Genes Associated With Vitamin D Deficiency Status

2016 ◽  
Vol 30 (1) ◽  
pp. 31-36 ◽  
Author(s):  
Nicole A. Slater ◽  
Michelle L. Rager ◽  
Dawn E. Havrda ◽  
Arthur F. Harralson
Keyword(s):  
Vitamin D ◽  
Vitamin D Deficiency ◽  
Serum Vitamin ◽  
Cross Sectional Study ◽  
Total Serum ◽  
Cross Sectional ◽  
Serum Vitamin D ◽  
Vitamin D Levels ◽  
25 Hydroxy Vitamin D ◽  
Variant Alleles

This cross-sectional study enrolled 180 patients at a private family practice in Virginia. Total serum vitamin D concentrations were obtained weekly from January 30, 2013, through March 30, 2013, in consecutive patients regularly scheduled for laboratory work at the practice. Patients were categorized into 2 groups and analyzed for variant alleles in vitamin D receptor ( VDR; rs2228570), cytochrome P450 2R1 ( CYP2R1; rs10741657), 7-dehydrocholesterol reductase ( DHCR7; rs12785878), and group-specific component ( GC; rs2282679) to determine whether variants of those alleles influenced total serum 25(OH)D concentrations. One-hundred and eighty patients were enrolled, with 40 (22%) being sufficient, 25-hydroxy vitamin D level 25(OH)D ≥ 30 ng/mL, and 140 (78%) being insufficient, 25(OH)D < 30 ng/mL. Of the 4 genes, 2 genes, CYP2R1 (rs10741657) and GC (rs2282679), demonstrated a significant association related to vitamin D status. Subjects with 1 or more variant alleles at rs10741657 were almost 3.7 (odds ratio [OR] 3.67; 95% confidence interval [CI]: 1.35-9.99) times more likely be insufficient in vitamin D and subjects with 1 or more variant alleles at rs2282679 were about half (OR 0.42; 95% CI: 0.18-0.93) as likely to be insufficient in vitamin D. Allelic variations in CYP2R1 (rs10741657) and GC (rs2282679) affect vitamin D levels, but variant alleles on VDR (rs2228570) and DHCR7 (rs12785878) were not correlated with vitamin D deficiency, 25(OH)D < 30 ng/mL.

scholarly journals SAT-017 Relationship Between Vitamin D Levels and Signs of Polycystic Ovary Syndrome

2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Anastasia Smykalova ◽  
Svetlana Kalinchenko ◽  
Aigul Safi ◽  
Mekan Orazov ◽  
Alexander Nizhnik
Keyword(s):  
Vitamin D ◽  
Waist Circumference ◽  
Vitamin D Deficiency ◽  
Polycystic Ovary ◽  
Serum Vitamin ◽  
The Body ◽  
Reproductive Age ◽  
Women Of Reproductive Age ◽  
Serum Vitamin D ◽  
Vitamin D Levels

Abstract An analysis of the structure of the causes of infertility shows that up to almost 25% of women of reproductive age ovulation disorders are observed. Hormonal disorders leading to the absence of ovulation, began to play a leading role in the etiology of infertility, special vitamin D deficiency, while today it has been established that its D receptors (VDR) are localized in most organs, including reproductive ones. VDR affect the expression of 1000 genes and play a crucial role in the implementation of sex hormones function. The aim of the study was to assess the vitamin D level in women of reproductive age, depending on the presence of signs of PCOS and waist circumference (WC). 71 women from 19 to 44 years old were examined of these, 41 patients were diagnosed with PCOS and impaired ovulatory function, in 30 patients the ovulatory cycle was preserved, and signs of PCOS were not detected. The level of vitamin 25 (OH) D3 in the serum of the subjects was evaluated by tandem chromato-mass spectrometry at the ArchiMed clinic of new medical technologies, Moscow. In the recommendations of the Canadian “The Vitamin D society”, 40-60 ng/ml the optimal level of serum vitamin D, a concentration of 20-40 ng/ml insufficiency, &lt;20 ng/ml as a deficiency. Vitamin D deficiency was detected in 57% of women in both groups, with a pronounced deficiency (&lt;10 ng/ml) in 17%, insufficiency was observed in 43% of cases, a sufficient level was not detected in any of the subjects. The average level of vitamin D in patients with PCOS was 18.2 (2 to 32.3) ng/ml, the value in patients without signs of PCOS was 18.5 (6.8 to 31) ng/ml. Comparison of the vitamin D value with WC showed that in women with PCOS with an WC &lt;80 cm the value of this indicator was 18.8 ng/ml, and for WC ≥ 80 cm it was statistically significantly lower - 13.3 ng/ml (p&lt;0.05). Conclusion. High prevalence of vitamin D deficiency among patients of reproductive age, with no differences in the magnitude of this indicator depending on the presence of signs of PCOS and persistent ovulation. Difference was established between the levels of vitamin D in patients with PCOS depending on the waist circumference - its insufficiency increases with an increase in WC. The results of the study suggest that the deficiency of vitamin D in the body increases with the aggravation of hormonal dysfunction in PCOS, which should be taken into account by specialists during the management of this category of patients and the treatment of infertility.

scholarly journals Association between Preeclampsia and vitamin D Deficiency

QJM ◽  
2020 ◽  
Vol 113 (Supplement_1) ◽  
Author(s):  
A S Elhoussieny ◽  
M E Ibrahim ◽  
H F Gad ◽  
E H Mahdi
Keyword(s):  
Vitamin D ◽  
Pregnant Women ◽  
Vitamin D Deficiency ◽  
Serum Vitamin ◽  
Maternity Hospital ◽  
Control Group ◽  
Major Health Problem ◽  
Serum Vitamin D ◽  
Vitamin D Levels ◽  
25 Hydroxy Vitamin D

Abstract Background Preeclampsia is a pregnancy-specific disorder that affects 3–5% of pregnant women worldwide and is one of the most frequently encountered medical complications of pregnancy. Recent research has pointed towards some role of vitamin D deficiency in pathogenesis of preeclampsia. Vitamin D deficiency in pregnant women and their children is a major health problem, with potential adverse consequences for overall health. Aim of the Study The aim of this study is to investigate the serum vitamin D levels in preeclampsia and healthy normotensive pregnant women. Patients and Methods This case control study was conducted at Ain Shams University Maternity Hospital from November 2017. The study included pregnant women 20-35years this study will be carried out on pregnant women recruited at pre labour room (preeclamptic group) and (non preeclamptic group) at Ain Shams University Maternity Hospital, 50 women in each group. Results All samples were screened by DRG® 25-OH Vitamin D (total) ELISA (EIA-5396) and it was found that mean 25 hydroxy vitamin D levels were lower in preeclamptic group than normotensive control group. Mean level of 25 hydroxy vitamin D between preeclamptic cases was 13.98 ±4.98 ng/ml and between normotensive controls was15.62± 3.51 ng/ml. Conclusion This study has shown no association between vitamin D deficiency and pre-eclampsia, supporting no role for vitamin D as a preventative agent against preeclampsia.

scholarly journals Relationship between Serum Vitamin D Levels and HDL Cholesterol in Postmenopausal Women from Colombian Caribbean

2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Luz Adriana Sarmiento-Rubiano ◽  
José Armando Angarita Ruidiaz ◽  
Héctor Fernando Suarez Dávila ◽  
Alfonso Suarez Rodríguez ◽  
Roberto C. Rebolledo-Cobos ◽  
...  
Keyword(s):  
Metabolic Syndrome ◽  
Vitamin D ◽  
Vitamin D Deficiency ◽  
Postmenopausal Women ◽  
Serum Vitamin ◽  
Hdl Cholesterol ◽  
Serum Vitamin D ◽  
The Metabolic Syndrome ◽  
Increased Risk ◽  
Vitamin D Levels

Background. Previous evidence suggests that metabolic disorders in postmenopausal women could be related with low serum vitamin D levels. For example, vitamin D deficiency has been associated with increased risk factors for cardiovascular disease (CVD), mainly those related with metabolic syndrome.Objective. To assess the relationship between the serum vitamin D (25-OH-D) levels and the metabolic syndrome markers in postmenopausal women.Methods. This descriptive and cross-sectional study was conducted in 183 postmenopausal women of four municipalities from Colombian Caribbean. The serum 25-OH-D levels and the anthropometric and biochemical markers were assessed and correlated with metabolic syndrome.Results. The average value of serum vitamin D (25-OH-D) was 26.34 ± 9.08 ng/mL, and 69.95% of the women had vitamin D levels <30 ng/mL, of which 43.72% were with insufficiency (<30 to >20 ng/mL) and 26.23% with deficiency (<20 ng/mL). Of the evaluated women, the 81.42% seemed to have metabolic syndrome. Through the linear regression, one significant positive association was observed between the HDL cholesterol and the 25-OH-D levels (P=0.014).Conclusion. In the evaluated population in this study, vitamin D deficiency is related with low HDL cholesterol levels.

Clinical factors correlated with vitamin D deficiency in patients with obesity scheduled for bariatric surgery: A single center experience

2020 ◽  
Vol 90 (3-4) ◽  
pp. 346-352
Author(s):  
Vincenzo Pilone ◽  
Salvatore Tramontano ◽  
Carmen Cutolo ◽  
Federica Marchese ◽  
Antonio Maria Pagano ◽  
...  
Keyword(s):  
Bariatric Surgery ◽  
Vitamin D ◽  
Vitamin D Deficiency ◽  
Serum Vitamin ◽  
Inverse Correlation ◽  
Model Assessment ◽  
Cross Sectional ◽  
Serum Vitamin D ◽  
Female Sex ◽  
Vitamin D Levels

Abstract. We aim to assess the prevalence of vitamin D deficiency (VDD) in patients scheduled for bariatric surgery (BS), and to identify factors that might be associated with VDD. We conducted a cross-sectional observational study involving all consecutive patients scheduled for BS from 2017 to 2019. The exclusion criteria were missing data for vitamin D levels, intake of vitamin D supplements in the 3 months prior to serum vitamin D determination, and renal insufficiency. A total of 206 patients (mean age and body mass index [BMI] of 34.9 ± 10.7 years, and 44.3 ± 6.99 kg/m2, respectively) met the inclusion criteria and were enrolled for data analysis. VDD (<19.9 ng/mL), severe VDD (<10 ng/mL), and vitamin D insufficiency (20–29.9 ng/mL) were present in 68.8 %, 12.5 %, and 31.2 % of patients, respectively. A significant inverse correlation was found between vitamin D levels and initial BMI, parathyroid hormone, and homeostatic model assessment of insulin resistance (r = −0.280, p < 0.05; r = −0.407, p = 0.038; r = −0.445, p = 0.005), respectively. VDD was significantly more prevalent in patients with higher BMI [−0.413 ± 0.12, CI95 % (−0.659; −0.167), p = 0.006], whereas no significant association between hypertension [−1.005 ± 1.65, CI95 % (−4.338; 2.326), p = 0.001], and diabetes type 2 (T2D) [−0.44 ± 2.20, CI95 % (−4.876; 3.986), p = 0.841] was found. We observed significant association between female sex and levels of vitamin D [6.69 ± 2.31, CI95 % (2.06; 11.33), p = 0.006]. The present study shows that in patients scheduled for BS, VDD deficiency is common and was associated with higher BMI, and female sex.

Association between vitamin D deficiency and prostate cancer: Prospective case-control study

2021 ◽  
pp. 205141582199360
Author(s):  
Ghanshyam Kumawat ◽  
Vijay Chaudhary ◽  
Anurag Garg ◽  
Nishkarsh Mehta ◽  
Gagan Talwar ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Vitamin D ◽  
Vitamin D Deficiency ◽  
Case Control Study ◽  
Serum Vitamin ◽  
P Value ◽  
Serum Vitamin D ◽  
Severe Vitamin ◽  
Vitamin D Levels ◽  
Control Study

Objective: We aimed to find out the association of low serum vitamin D levels with the incidence of prostate cancer through a prospective case-control study. Material and methods: This study was carried out in the tertiary care hospital (India). All newly diagnosed patients of prostate cancer and age-matched controls were included. Serum vitamin D levels were measured in all of them. Vitamin D status (ng/mL) was classified as severe deficiency <10, moderate deficiency 10–<30, normal 30–100, and toxicity >100. Normality of the data was tested by the Kolmogorov–Smirnov test, statistical analysis was done with Statistical Package for the Social Sciences version 26.0, p-value of <0.05 was considered significant. Results: In our study, 320 cases and 320 controls were included. The mean vitamin D levels in cases and controls were 15.71 ± 6.5 (ng/mL) and 17.63 ± 4.54 (ng/mL), respectively, ( p-Value <0.01). Patients with severe vitamin D deficiency (73.58%) had a Gleason score ⩾8 on biopsy and 79.24% of them had a serum prostate specific antigen (PSA) level >20 ng/mL. Conclusion: We had concluded that there was no significant association between vitamin D deficiency and increased risk of prostate cancer, although patients with higher-grade prostate cancer and with higher PSA level had severe vitamin D deficiency. Level of evidence: Not applicable for this multicentre audit.

scholarly journals Correlation of psoriasis and serum vitamin D

2021 ◽  
Vol 7 (4) ◽  
pp. 320-323
Author(s):  
Ritika Gujrati ◽  
Krishnendra Varma ◽  
Ujjwal Kumar
Keyword(s):  
Vitamin D ◽  
Vitamin D Deficiency ◽  
Psoriasis Vulgaris ◽  
Systemic Disease ◽  
Serum Vitamin ◽  
Psoriatic Skin ◽  
Control Group ◽  
P Value ◽  
Serum Vitamin D ◽  
Vitamin D Levels

Psoriasis is an immuno-mediated chronic systemic disease involving cytokines of helper Th1 pathway. Vitamin D has an effect on keratinocyte proliferation, differentiation and immune modulation of immune system especially Th1 pathway, which is altered in psoriatic skin suggesting that Vitamin D may have a role in pathogenesis of psoriasis. To study correlation between psoriasis vulgaris and serum vitamin D. To evaluate serum vitamin D level in psoriasis cases and in control group and correlating vitamin D level with severity and duration of the psoriasis. 57 cases (&#62;15years of age) with psoriasis and 57 healthy subjects were recruited. Psoriasis was clinically diagnosed and severity evaluated by PASI scale. Vitamin D was analysed by enhanced chemilumine scence on vitrus Eci autoanalyzer of Orth clinical diagnostic. Vitamin D deficiency defined as &#60;20ng/ml, insufficiency 20-30ng/ml and sufficient 30-100ng/ml. Vitamin D deficiency in the study was 22.8% in patients and 14% in control group. Vitamin D insufficiency was found in 42.1% of cases and 19.3% of control. According to chi-square the p-value is 0.003 showing significant association. There was a tendency towards decrease in vitamin D level with increase in disease duration. There was negative correlation between vitamin D and PASI score. The study found a significant relationship between vitamin D and psoriasis. Further metanalysis involving larger study population will be required to establish whether vitamin D levels benefits patient with psoriasis vulgaris.

scholarly journals Rate of hypovitaminosis D and association of plasma concentration of 25(OH)D with indicators of disease activity in patients with rheumatoid arthritis

2020 ◽  
Vol 64 (6) ◽  
pp. 723-729
Author(s):  
A. V. Rudenko ◽  
T. D. Tyabut ◽  
A. E. Buglova ◽  
G. A. Babak ◽  
P. M. Morozik ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
Vitamin D ◽  
Disease Activity ◽  
Vitamin D Deficiency ◽  
Activity Index ◽  
Serum Vitamin ◽  
Disease Activity Index ◽  
Tender Joint Count ◽  
Serum Vitamin D ◽  
Vitamin D Levels

Vitamin D deficiency is an important environmental risk factor that influences the prevalence and severity of several autoimmune diseases, including rheumatoid arthritis (RA). The aim of this study was to determine the incidence of vitamin D insufficiency and deficiency in patients with RA, to establish the relationship between serum vitamin D levels and indicators of disease activity. 156 patients with RA were included in the study, mean age 60.2 ± 13.9 years. Assessment of clinical status was performed, serum concentrations of rheumatoid factor (RF), C-reactive protein (CRP), total vitamin D (25(OH)D), antibodies to cyclic citrullinated peptide (ACCP) were determined. RA disease activity was evaluated using DAS28 (disease activity score), SDAI (Simplified Disease Activity Index) и CDAI (Clinical Disease Activity Index) scores. Average levels of 25(OH)D in the surveyed sample were 25.2 ± 13.2 ng/ml. The results of the study indicate a high prevalence of vitamin D deficiency in patients with RA. Normal indicators of vitamin D, its insufficiency and deficiency were observed in 47 (30.3 %), 45 (28.7 %) and 64 (40.7 %) patients, respectively. Low level of serum 25(OH)D was associated with higher indices of RA activity according to DAS28, SDAI and CDAI, as well as with greater tender joint count. Vitamin D should be prescribed as an adjunctive therapy in patients with active RA due to its potential immunomodulatory effect, as well as for the prevention and treatment of bone metabolism disorders.

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