scholarly journals Challenges Ahead for a Rational Analysis of Vitamin D in Athletes

2021 ◽  
Vol 8 ◽  
Author(s):  
Pedro Araujo ◽  
Cioly Méndez-Dávila
Keyword(s):  
Vitamin D ◽  
Statistical Power ◽  
Calcium Absorption ◽  
Underlying Mechanism ◽  
Effective Management ◽  
Rational Analysis ◽  
Golden Standard ◽  
Analytical Quantification ◽  
And Performance ◽  
Comprehensive Study

Vitamin D is an essential vitamin for the normal formation of bones and calcium absorption. It is synthesized into our body through sunlight exposure and obtained by consuming foods rich in vitamin D (e.g., fatty fish, eggs yolk, dairy products). Its benefits on the health and performance of athletes are well documented. This article outlines some analytical challenges concerning the analytical quantification of vitamin D for its optimal intake, namely, a comprehensive study of the variability of the assay before categorizing any method as the golden standard, assurance of sample comparability to draw meaningful correlations, revision of the intake guidance based on appropriate statistical power analysis, and the implementation of rational strategies for preventing the underlying mechanism of preanalytical factors. Addressing these challenges will enable the effective management of vitamin D in the sports sector.

Replication of the Superstition and Performance Study by

2014 ◽  
Vol 45 (3) ◽  
pp. 239-245 ◽  
Author(s):  
Robert J. Calin-Jageman ◽  
Tracy L. Caldwell
Keyword(s):  
Task Difficulty ◽  
Statistical Power ◽  
Meta Analysis ◽  
A Priori ◽  
Significant Heterogeneity ◽  
Performance Study ◽  
Improve Performance ◽  
Research Designs ◽  
Series Of Experiments ◽  
And Performance

A recent series of experiments suggests that fostering superstitions can substantially improve performance on a variety of motor and cognitive tasks ( Damisch, Stoberock, & Mussweiler, 2010 ). We conducted two high-powered and precise replications of one of these experiments, examining if telling participants they had a lucky golf ball could improve their performance on a 10-shot golf task relative to controls. We found that the effect of superstition on performance is elusive: Participants told they had a lucky ball performed almost identically to controls. Our failure to replicate the target study was not due to lack of impact, lack of statistical power, differences in task difficulty, nor differences in participant belief in luck. A meta-analysis indicates significant heterogeneity in the effect of superstition on performance. This could be due to an unknown moderator, but no effect was observed among the studies with the strongest research designs (e.g., high power, a priori sampling plan).

OCCULT MALABSORPTION CAUSING OSTEITIS FIBROSA CYSTICA

1962 ◽  
Vol 40 (4) ◽  
pp. 481-492
Author(s):  
J. G. Devlin ◽  
D. K. O'Donovan
Keyword(s):  
Vitamin D ◽  
Iron Absorption ◽  
Calcium Absorption ◽  
Calcium Balance ◽  
Gluten Free ◽  
Osteitis Fibrosa Cystica ◽  
Mucosal Atrophy ◽  
Cystic Changes ◽  
Calcium Malabsorption ◽  
Radiological Examinations

ABSTRACT A case is reported of intermittent hypercalcaemia, hypophosphataemia and severe skeletal rarefaction with cystic changes. An occult calcium malabsorption was found. Fat, triolein and iron absorption and radiological examinations were normal. There was gross intestinal mucosal atrophy. She was shown to be in a state of negative calcium balance and this was reversed by vitamin D. A gluten-free diet also improved calcium absorption. It is postulated that the patient had severe secondary hyperparathyroidism as the skeleton reverted to normal after six months of medical treatment.

artikel 9 admistrasi layanan khusus

2020 ◽  
Author(s):  
syafriati
Keyword(s):  
Service Management ◽  
School Level ◽  
Effective Management ◽  
Class Inclusion ◽  
Program Monitoring ◽  
Special Services ◽  
Management Processes ◽  
Special Service ◽  
And Performance ◽  
Management Functions

Special services provided by schools to students are generally the same, but different on the process of the management and utilization. Some form of special services in school is the service: councelling, libraries, laboratories, extracurricular, infirmary, cafeteria, cooperatives, OSIS, transport, boarding, acceleration, class inclusion, and apprentice. As a special service management functions include: (1) planning, such as needs analysis and programming of special services; (2) the organization, such as the division of tasks to carry out special service program; (3) in motion, in the form of the settings in the implementation of special services, and (4) control, in the form of program monitoring and performance assessment special services program in school. So that special services should be managed with effective management processes in order to strengthen the management process of education, particularly at the school level.

Calcium absorption and vitamin D in the chick

1951 ◽  
Vol 34 (1) ◽  
pp. 105-111 ◽  
Author(s):  
B.B. Migicovsky ◽  
A.M. Nielson
Keyword(s):  
Vitamin D ◽  
Calcium Absorption

scholarly journals The Implications of Regulatory Framework for Topical Semisolid Drug Products: From Critical Quality and Performance Attributes towards Establishing Bioequivalence

Pharmaceutics ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 710
Author(s):  
Tanja Ilić ◽  
Ivana Pantelić ◽  
Snežana Savić
Keyword(s):  
Statistical Power ◽  
Failure Modes ◽  
In Vitro Release ◽  
Optimal Number ◽  
Drug Products ◽  
Pharmaceutical Equivalence ◽  
And Performance ◽  
Low Sensitivity

Due to complex interdependent relationships affecting their microstructure, topical semisolid drug formulations face unique obstacles to the development of generics compared to other drug products. Traditionally, establishing bioequivalence is based on comparative clinical trials, which are expensive and often associated with high degrees of variability and low sensitivity in detecting formulation differences. To address this issue, leading regulatory agencies have aimed to advance guidelines relevant to topical generics, ultimately accepting different non-clinical, in vitro/in vivo surrogate methods for topical bioequivalence assessment. Unfortunately, according to both industry and academia stakeholders, these efforts are far from flawless, and often upsurge the potential for result variability and a number of other failure modes. This paper offers a comprehensive review of the literature focused on amending regulatory positions concerning the demonstration of (i) extended pharmaceutical equivalence and (ii) equivalence with respect to the efficacy of topical semisolids. The proposed corrective measures are disclosed and critically discussed, as they span from mere demands to widen the acceptance range (e.g., from ±10% to ±20%/±25% for rheology and in vitro release parameters highly prone to batch-to-batch variability) or reassess the optimal number of samples required to reach the desired statistical power, but also rely on specific data modeling or novel statistical approaches.

The Temporal Distribution of the 1α,25-Dihydroxycholecalciferol Receptor in the Rat Jejunal Villus

1984 ◽  
Vol 67 (3) ◽  
pp. 285-290 ◽  
Author(s):  
S. D. H. Chan ◽  
D. Atkins
Keyword(s):  
Vitamin D ◽  
Vitamin D Deficiency ◽  
Calcium Absorption ◽  
Sedimentation Coefficient ◽  
Temporal Distribution ◽  
High Affinity ◽  
High Affinity Receptor ◽  
Affinity Receptor ◽  
Cell Fractions ◽  
Crypt Cells

1. The distribution of the 1α,25-dihydroxycholecalciferol receptor was studied in enterocytes isolated from the upper, mid and lower villus and crypt cells of the jejunum of normal and rachitic rats. 2. In all cell fractions a high-affinity receptor (KD ⋍ 0.07 nmol/l) with a sedimentation coefficient of 3.5S was demonstrated. 3. In normal rats there was a 60% reduction in receptor numbers in crypt cells compared with the mid and upper villous cells. 4. Vitamin D deficiency led to a reduction in receptor numbers in all cell fractions (45% upper villus, 78% crypt cells). 5. The data are compatible with the concept of calcium absorption occurring in the differentiated villous cells and also account for the reduction in absorption in rachitic animals.

SEVERE IDIOPATHIC HYPERCALCEMIA OF INFANCY

PEDIATRICS ◽  
1957 ◽  
Vol 19 (3) ◽  
pp. 362-371
Author(s):  
George L. Daeschner ◽  
C. William Daeschner
Keyword(s):  
Vitamin D ◽  
Renal Function ◽  
Impaired Renal Function ◽  
Calcium Absorption ◽  
Severe Form ◽  
Additional Case ◽  
Mild Form ◽  
Laboratory Findings ◽  
Pathologic Features ◽  
Motor Retardation

A syndrome occurring in infants and characterized clinically by anorexia, vomiting, constipation, hypotonia, hypertension, characteristic facies, and severe mental-motor retardation, and by the laboratory findings of hypercalcemia, azotemia and impaired renal function has recently been described by British and Swiss workers. The disease apparently occurs in two forms, referred to as mild and severe. The literature concerning the severe form has been reviewed and an additional case reported. Hypersensitivity to vitamin D with excessive calcium absorption has been demonstrated in the mild form of this syndrome and has also been proposed as the metabolic abnormality responsible for the pathologic features of the severe form of the disease.

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