scholarly journals Radiographic analysis of the thickness of the cranial bones in captive compared to wild-living cheetahs and in cheetahs with hypovitaminosis A

PLoS ONE ◽  
2021 ◽  
Vol 16 (8) ◽  
pp. e0255924
Author(s):  
Martin J. Schmidt ◽  
Gerhard Steenkamp ◽  
Peter Caldwell ◽  
Klaus Failing ◽  
Robert M. Kirberger
Keyword(s):  
Vitamin A ◽  
Health Management ◽  
Vitamin A Deficiency ◽  
Serum Levels ◽  
Bone Thickness ◽  
Calvarial Bone ◽  
Presumptive Diagnosis ◽  
Vitamin A Status ◽  
Skull Radiographs ◽  
Hypovitaminosis A

Captive cheetahs often demonstrate a high incidence of diseases in which vitamin A imbalances are implicated. These can occur even under controlled and optimised feeding regimens, which is why surveillance of vitamin A status is mandatory in the successful health management of cheetahs. Serum levels of the vitamin do not reflect the true vitamin A status and liver tissue analysis is rather impractical for routine application in large felids. A biomarker for evaluating overt and subclinical vitamin A deficiency in cheetahs is needed. This study evaluates whether increased calvarial bone thickness can be detected on routine skull radiographs of vitamin A deficient cheetahs compared to unaffected animals, and secondly, evaluates whether there is increased bone thickness in clinically sound captive cheetahs in general compared to wild-living controls. Bone thickness in the neuro- and splanchnocranium was measured in 138 skull radiographs. Significant thickening of the parietal bones was found in latero-lateral radiographs of immature cheetahs (< 12 months) with vitamin A deficiency. This finding may allow a presumptive diagnosis of hypovitaminosis A in immature cheetahs. A general difference in skull thickness between free-living and captive cheetahs was not found.

Research Recommendations for Applying Vitamin A-Labelled Isotope Dilution Techniques to Improve Human Vitamin A Nutrition

2014 ◽  
Vol 84 (Supplement 1) ◽  
pp. 52-59 ◽  
Author(s):  
Sherry A. Tanumihardjo ◽  
Anura V. Kurpad ◽  
Janet R. Hunt
Keyword(s):  
Public Health ◽  
Vitamin A ◽  
Vitamin A Deficiency ◽  
Human Subjects ◽  
The Body ◽  
Pool Size ◽  
Serum Retinol ◽  
Vitamin A Status ◽  
Status Assessment ◽  
Total Body

The current use of serum retinol concentrations as a measurement of subclinical vitamin A deficiency is unsatisfactory for many reasons. The best technique available for vitamin A status assessment in humans is the measurement of total body pool size. Pool size is measured by the administration of retinol labelled with stable isotopes of carbon or hydrogen that are safe for human subjects, with subsequent measurement of the dilution of the labelled retinol within the body pool. However, the isotope techniques are time-consuming, technically challenging, and relatively expensive. There is also a need to assess different types of tracers and doses, and to establish clear guidelines for the use and interpretation of this method in different populations. Field-friendly improvements are desirable to encourage the application of this technique in developing countries where the need is greatest for monitoring the risk of vitamin A deficiency, the effectiveness of public health interventions, and the potential of hypervitaminosis due to combined supplement and fortification programs. These techniques should be applied to validate other less technical methods of assessing vitamin A deficiency. Another area of public health relevance for this technique is to understand the bioconversion of β-carotene to vitamin A, and its relation to existing vitamin A status, for future dietary diversification programs.

Vitamin A Supplementation and Measles

1995 ◽  
Vol 16 (9) ◽  
pp. 358-359
Author(s):  
Glenn J. Fennelly
Keyword(s):  
Vitamin A ◽  
Acute Phase ◽  
Vitamin A Deficiency ◽  
Serum Levels ◽  
Morbidity And Mortality ◽  
Serum Retinol ◽  
Vitamin A Supplementation

Vitamin A deficiency resulting from inadequate intake or induced by infection is associated with increased morbidity and mortality. Measles, the major single infectious cause of mortality in children worldwide, is more severe in children who have preexisting vitamin A deficiency. Several recent studies suggest that: 1) measles is associated with depressed serum levels of vitamin A; 2) hyporetinemia, defined as a serum retinol of less than 0.7 µmol/L, is associated with increased mortality from measles, especially in children younger than 2 years of age; and 3) vitamin A will decrease the risk of complications and death when administered during the acute phase of illness (within 5 days of the onset of rash).

Genotype Effects on β-Carotene Conversion to Vitamin A: Implications on Reducing Vitamin A Deficiency in the Philippines

2021 ◽  
pp. 037957212110602
Author(s):  
Mark Pretzel P. Zumaraga ◽  
Jose Maria Reynaldo Apollo Arquiza ◽  
Mae Anne Concepcion ◽  
Leah Perlas ◽  
Ma. Neda Alcudia-Catalma ◽  
...  
Keyword(s):  
Vitamin A ◽  
Children And Adolescents ◽  
Vitamin A Deficiency ◽  
The Philippines ◽  
Fisher Exact Test ◽  
National Capital Region ◽  
Nutrition Survey ◽  
Vitamin A Status ◽  
Genotype Frequencies

Background: The study aimed to identify two beta-carotene 15,15′-monooxygenase (BCMO1) mutations, namely R267S and A379V, and determine their association with vitamin A status among Filipinos 6 to 19 years old respondents of the 2013 Philippine National Nutrition Survey living in the National Capital Region. Materials and Methods: This study followed cross-sectional design. Whole blood specimen was collected in the morning and was used as source of genomic DNA and serum for retinol concentration determination. Fisher exact test was performed to determine whether genotype frequencies were associated to retinol concentrations/vitamin A deficiency status. A level of P < .05 was identified as significant. Results: A total of 693 Filipino children and adolescents were included. Of the 693, there were at least 7.6% who bears the combined mutations for R267S + A379V. Association analysis showed that an inverse relationship exists between the A379V TT variant and vitamin A status. Although the exact role of these identified polymorphisms on retinol/carotenoid metabolism need to be confirmed in dedicated functional studies. Conclusion: This study has identified for the first time the presence of 2 nonsynonymous genetic variants/mutations in the coding region of BCMO1 gene. Interestingly, one of these two variants, the A379V T, was found to be associated with vitamin A status. It is, therefore, warranted to investigate the role of BCMO1 variants for the success of supplementation programs and fortification efforts among vulnerable populations in this region. Genetic variability should be considered for future provitamin A supplementation recommendations among children and adolescents in the Philippines.

scholarly journals Vitamin A Supplementation and Child Morbidity and Mortality in Developing Countries

1994 ◽  
Vol 15 (4) ◽  
pp. 1-9 ◽  
Author(s):  
George H. Beaton ◽  
Reynaldo Martorell ◽  
Kristan A. Aronson ◽  
Barry Edmonston ◽  
George McCabe. A. Catharine Ross ◽  
...  
Keyword(s):  
Vitamin A ◽  
Respiratory Infections ◽  
Vitamin A Deficiency ◽  
Meta Analysis ◽  
Clinical Signs ◽  
Vitamin A Status ◽  
Child Morbidity ◽  
Age Profile ◽  
Mortality Trials ◽  
Low Prevalence

A meta-analysis of eight mortality trials indicates that improving the vitamin A status of children aged six months to five years reduced mortality rates by about 23% in populations with at least low prevalence of clinical signs of vitamin A deficiency. The observed effect of supplementation, described in terms of relative risk (RR), was RR =0.77 (95% confidence interval 0.68–0.88; p < .001) and did not differ by sex or age. However, the number of lives saved was greater at younger ages because of higher mortality. A significant RR was shown for deaths attributed to diarrhoea and measles, but not for respiratory infection. Variability among the trials in effects was apparent, but attempts to explain it by descriptors of the population (baseline anthropometric status, prevalence of xerophthalmia, age profile, baseline mortality) were unsuccessful. Owing to the lack of data, firm conclusions could not be reached about effectiveness in children of less than six months and in settings where biochemical but not clinical evidence of vitamin A deficiency exists. Information about morbidity outcomes from about two dozen studies was reviewed. No consistent effects on frequency or prevalence of diarrhoeal and respiratory infections were found. Improvement in vitamin A status did appear to reduce severe morbidity, particularly in children with measles.

scholarly journals Cassava with enhanced β-carotene maintains adequate vitamin A status in Mongolian gerbils (Meriones unguiculatus) despite substantial cis-isomer content

2009 ◽  
Vol 102 (3) ◽  
pp. 342-349 ◽  
Author(s):  
Julie A. Howe ◽  
Bussie Maziya-Dixon ◽  
Sherry A. Tanumihardjo
Keyword(s):  
Vitamin A ◽  
Vitamin A Deficiency ◽  
Meriones Unguiculatus ◽  
Provitamin A ◽  
Carotenoid Content ◽  
Mongolian Gerbils ◽  
Serum Retinol ◽  
Vitamin A Status ◽  
Isomer Content ◽  
Β Carotene

Efforts to increase β-carotene in cassava have been successful, but the ability of high-β-carotene cassava to prevent vitamin A deficiency has not been determined. Two studies investigated the bioefficacy of provitamin A in cassava and compared the effects of carotenoid content and variety on vitamin A status in vitamin A-depleted Mongolian gerbils (Meriones unguiculatus). Gerbils were fed a vitamin A-free diet 4 weeks prior to treatment. In Expt 1, treatments (ten gerbils per group) included 45 % high-β-carotene cassava, β-carotene and vitamin A supplements (intake matched to high-β-carotene cassava group), and oil control. In Expt 2, gerbils were fed cassava feeds with 1·8 or 4·3 nmol provitamin A/g prepared with two varieties. Gerbils were killed after 4 weeks. For Expt 1, liver vitamin A was higher (P < 0·05) in the vitamin A (1·45 (sd 0·23) μmol/liver), lower in the control (0·43 (sd 0·10) μmol/liver), but did not differ from the β-carotene group (0·77 (sd 0·12) μmol/liver) when compared with the high-β-carotene cassava group (0·69 (sd 0·20) μmol/liver). The bioconversion factor was 3·7 μg β-carotene to 1 μg retinol (2 mol:1 mol), despite 48 % cis-β-carotene [(Z)-β-carotene] composition in cassava. In Expt 2, cassava feed with 4·3 nmol provitamin A/g maintained vitamin A status. No effect of cassava variety was observed. Serum retinol concentrations did not differ. β-Carotene was detected in livers of gerbils receiving cassava and supplements, but the cis-to-trans ratio in liver differed from intake. Biofortified cassava adequately maintained vitamin A status and was as efficacious as β-carotene supplementation in the gerbil model.

Vitamin A Status and Hepatic Drug Metabolism in the Rat

1973 ◽  
Vol 51 (1) ◽  
pp. 6-11 ◽  
Author(s):  
G. C. Becking
Keyword(s):  
Vitamin A ◽  
Drug Metabolism ◽  
Vitamin A Deficiency ◽  
Hepatic Drug Metabolism ◽  
Deficient Diet ◽  
Hepatic Drug ◽  
Vitamin A Status ◽  
Cytochrome P 450 ◽  
Liver Vitamin

The effect of vitamin A status on hepatic drug metabolism was studied in rats. Animals were fed diets with and without vitamin A for 20 and 25 days. Weight gains of control and deficient animals were not significantly different, whereas liver vitamin A levels had decreased to less than 10% of control animals after 20 days and were essentially zero after eating the deficient diet for 25 days. Aniline metabolism in vitro and aminopyrine metabolism in vitro and in vivo were significantly lower in male weanling rats fed a vitamin A deficient diet for 20 days. No alteration in in vitro p-nitrobenzoic acid metabolism was noted after 25 days on the test. Vitamin A deficiency did not alter microsomal protein levels or cytochrome c reductase activity but deficient animals did have a lower microsomal cytochrome P-450 content. Hepatic enzyme activities and cytochrome P-450 levels were restored to values approaching those found in control animals by feeding vitamin A deficient rats the vitamin A containing diet for 21 days. Liver vitamin A levels were markedly increased after re-feeding studies but were still significantly lower than control animals.

scholarly journals Production of chickens with marginal vitamin A deficiency

1992 ◽  
Vol 68 (1) ◽  
pp. 283-291 ◽  
Author(s):  
Clive E. West ◽  
S. Reinder Sijtsma ◽  
Harry P. F. Peters ◽  
Jan H. W. M. Rombout ◽  
Akke J. Van Der Zijpp
Keyword(s):  
Body Weight ◽  
Vitamin A ◽  
General Health ◽  
Egg Production ◽  
Narrow Range ◽  
Vitamin A Deficiency ◽  
Generation Model ◽  
Vitamin A Status ◽  
Plasma Retinol ◽  
High Level

Marginally vitamin A-deficient 1-d-old chickens capable of remaining healthy for at least 6 weeks were produced using a two-generation model. In this model, hens fed on diets with a limited vitamin A content were used to obtain 1-d-old chickens which were marginally deficient in vitamin A. Only hens with a narrow range of plasma retinol values (0.60–0.85 μmol/l) were satisfactory for this purpose. Above this range the 1-d-old chickens were not marginally vitamin A deficient. Below this range egg production and hatchability were affected to some extent depending on the degree of vitamin A deficiency. Even when egg production and hatchability remained at a high level in such birds, the 1-d-old chickens produced were not sufficiently strong to survive the first weeks of life. The advantages of the two-generation model for producing marginally vitamin A-deficient chickens are the increased uniformity and predictability of the chickens with respect to body-weight, general health and vitamin A status. However, it does take about 3 months to produce such chickens.

scholarly journals Use of the retinol-binding protein : transthyretin ratio for assessment of vitamin A status during the acute-phase response

2000 ◽  
Vol 83 (5) ◽  
pp. 513-520 ◽  
Author(s):  
Suzanne M. Filteau ◽  
Juana F. Willumsen ◽  
Keith Sullivan ◽  
Karin Simmank ◽  
Mary Gamble
Keyword(s):  
Vitamin A ◽  
Sensitivity And Specificity ◽  
Assessment Tool ◽  
Binding Protein ◽  
Vitamin A Deficiency ◽  
Retinol Binding Protein ◽  
Serum Retinol ◽  
Vitamin A Status ◽  
Plasma Retinol

The ratio plasma retinol-binding protein (RBP) : transthyretin (TTR) has been proposed as a means to improve the assessment of vitamin A status of individuals with concurrent infection or inflammation. We have measured RBP and TTR in stored sera from South African children who had accidentally ingested kerosene. Samples were collected from these children in hospital when suffering acute inflammation and respiratory distress, and from them and neighbourhood control children 3 months later. Vitamin A status was defined by modified relative dose response (MRDR) tests of liver retinol stores at 3 months and by serum retinol concentration both when children were ill and when they were well. Illness was defined as either being in hospital or, at follow-up, as having a raised plasma α1-acid glycoprotein (AGP) level. The RBP : TTR value was significantly decreased by both illness and low liver retinol stores. When the effects on RBP : TTR of illness and vitamin A stores were considered together for the 3-month follow-up samples, only vitamin A status significantly decreased the value. We calculated sensitivity and specificity of the RBP : TTR ratio against established measures of vitamin A status using a cut-off value of 0·3 for RBP : TTR and standard cut-off values for MRDR (0·06) and plasma retinol (0·7 μmol/l). Compared with MRDR, RBP : TTR had sensitivities of 76 % and 43 % and specificities of 22 % and 81 % to detect vitamin A deficiency in hospitalized and well children respectively. Compared with plasma retinol, sensitivities were 88 % and 44 % and specificities were 55 % and 64 % in hospitalized and well children respectively. Only for the case of clinically well children with biochemical evidence of subclinical inflammation did sensitivity (62 % and 100 % against MRDR and plasma retinol respectively) and specificity (100 % and 60 % against MRDR and retinol) approach useful levels for an assessment tool. Overall, although a trend supporting the theory behind the use of the RBP : TTR for assessment of vitamin A status in infection was observed in the current study, the ratio did not provide adequate sensitivity and specificity to be a useful assessment tool.

scholarly journals Maize meal fortification is associated with improved vitamin A and iron status in adolescents and reduced childhood anaemia in a food aid-dependent refugee population

2008 ◽  
Vol 11 (7) ◽  
pp. 720-728 ◽  
Author(s):  
Andrew Seal ◽  
Emmanuel Kafwembe ◽  
Ismail AR Kassim ◽  
Mei Hong ◽  
Annie Wesley ◽  
...  
Keyword(s):  
Vitamin A ◽  
Vitamin A Deficiency ◽  
Iron Status ◽  
Household Survey ◽  
Refugee Camp ◽  
Food Aid ◽  
Serum Retinol ◽  
Post Intervention ◽  
Vitamin A Status ◽  
Maize Meal

AbstractObjectiveTo assess changes in the Fe and vitamin A status of the population of Nangweshi refugee camp associated with the introduction of maize meal fortification.DesignPre- and post-intervention study using a longitudinal cohort.SettingNangweshi refugee camp, Zambia.SubjectsTwo hundred and twelve adolescents (10–19 years), 157 children (6–59 months) and 118 women (20–49 years) were selected at random by household survey in July 2003 and followed up after 12 months.ResultsMaize grain was milled and fortified in two custom-designed mills installed at a central location in the camp and a daily ration of 400 g per person was distributed twice monthly to households as part of the routine food aid ration. During the intervention period mean Hb increased in children (0·87 g/dl;P< 0·001) and adolescents (0·24 g/dl;P= 0·043) but did not increase in women. Anaemia decreased in children by 23·4 % (P< 0·001) but there was no significant change in adolescents or women. Serum transferrin receptor (log10-transformed) decreased by −0·082 μg/ml (P= 0·036) indicating an improvement in the Fe status of adolescents but there was no significant decrease in the prevalence of deficiency (−8·5 %;P= 0·079). In adolescents, serum retinol increased by 0·16 μmol/l (P< 0·001) and vitamin A deficiency decreased by 26·1 % (P< 0·001).ConclusionsThe introduction of fortified maize meal led to a decrease in anaemia in children and a decrease in vitamin A deficiency in adolescents. Centralised, camp-level milling and fortification of maize meal is a feasible and pertinent intervention in food aid operations.

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