scholarly journals Challenge of Virus Disease Threats to Ensuring Sustained Uptake of Vitamin-A-Rich Sweetpotato in Africa

Author(s):  
Jan Kreuze ◽  
Wilmer J. Cuellar ◽  
Jan W. Low

AbstractOrange-fleshed sweetpotatoes (OFSP) are a rich source of pro-vitamin A and can alleviate vitamin A deficiency in the developing world. In Africa, traditional varieties have been almost exclusively white-fleshed and introduction and breeding of orange-fleshed varieties into Africa has been severely hampered by virus diseases to which many varieties are susceptible. Breeding progress to generate resistant varieties has been slow due to rare and recessive occurrence of resistance in breeding populations. Production of virus-free seed is complicated by the fact that most sweetpotato viruses show no or only limited symptoms and very low virus concentrations when infected by individual viruses, making them difficult to detect. Even single infections can lead to significant yield losses, but when they combine severe disease complexes are generated, which can lead to total crop failure. Significant efforts have been made in characterizing and understanding virus interactions in sweetpotato over the last two decades to address this challenge; they are reviewed in this chapter. We also review the state of the art in detection of viruses in support of seed systems and breeding. We conclude with recommendations for the most urgent future research directions needed to address virus problems in sweetpotatoes.

2021 ◽  
Vol 5 (Supplement_2) ◽  
pp. 73-73
Author(s):  
Catherine Johnson ◽  
Sophia Brown ◽  
Chandler Phelps ◽  
Chisela Kaliwile ◽  
Jesse Sheftel ◽  
...  

Abstract Objectives Vitamin A deficiency (VAD) has remained a leading cause of morbidity and mortality throughout the world for decades, however there are still challenges defining VA status because the most common biomarker, serum retinol, is regulated homeostatically except in extreme deficiency and affected by inflammation; therefore, more accurate biomarkers to define VAD are needed. Furthermore, the effects of VAD on metabolism are still being uncovered. The objective was to investigate whether serum metabolomics profiles differed between Zambian women with adequate versus deficient VA status measured by the gold-standard biomarker total liver VA reserves (TLR) whose serum retinol concentrations did not differ. Methods Retinol isotope dilution (RID) was used to estimate TLR in Zambian women in the Rufunsa district; serum aliquots were selected for metabolomics based on adequate (TLR > 0.1–1 μmol VA/g liver) or deficient (TLR < 0.1 μmol/g) VA status (n = 10/group). Serum retinol levels were indicative of adequacy (>0.7 μmol/L) and were not different between groups. Serum samples were analyzed by LC-MS using four metabolomics assays. Metabolomics data were covariate-adjusted for age and BMI. Results Ten metabolites were different between the adequate and deficient vitamin A groups (P < 0.05). Metabolites lower in the deficient group included multiple phosphatidylcholines (PCs) and phosphatidylethanolamines (PEs), as well as lipoxygenase (LOX)-derived oxylipins (9-HODE and 17-HDoHE), choline, and anthranilic acid. One cholestryl ester was elevated in the deficient group. Conclusions The study revealed numerous metabolites altered by RID-measured VAD and adequacy despite similarly adequate serum retinol levels in both groups. Future research is required to investigate the mechanisms by which phospholipids such as PCs and PEs, as well as LOX-derived oxylipins, are altered by VA status and the potential use of these metabolites as biomarkers of VAD. Funding Sources University of Wisconsin-Madison Global Health Institute visiting scholar fellowship (CK and SAT).


Nutrients ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 1286 ◽  
Author(s):  
Corrine Hanson ◽  
Elizabeth Lyden ◽  
Ann Anderson-Berry ◽  
Nicholas Kocmich ◽  
Amy Rezac ◽  
...  

Vitamin A is an essential nutrient in pregnancy, and other carotenoids have been independently associated with maternal-infant outcomes. The objective of this study was to quantify the status of vitamin A and carotenoids in Nigerian maternal-infant pairs at delivery, compare these to a cohort from a developed nation, and determine the impact on clinical outcomes. Maternal and cord blood samples were collected in 99 Nigerian mother-infant pairs. Concentrations of lutein + zeaxanthin, β-cryptoxanthin, lycopene, α- and β-carotenes, and retinol were measured using HPLC. Descriptive statistics were calculated and Spearman coefficients were used to assess correlations between maternal and cord measurements; Mann-Whitney tests were used to compare median plasma values between dichotomous variables. Linear regression models were used to adjust for relevant confounders. A p < 0.05 was considered statistically significant. Thirty-five percent of mothers had plasma retinol concentrations ≤0.70 µmol/L; 82% of infants had plasma retinol concentrations ≤0.70 µmol/L at delivery. Maternal and infant concentrations of vitamin A compounds were highly correlated and were associated with newborn growth and Apgar scores. Despite plasma concentrations of pro-vitamin A carotenoids higher than those reported in other populations, pregnant Nigerian women have a high prevalence of vitamin A deficiency. As vitamin A related compounds are modifiable by diet, future research determining the clinical impact of these compounds is warranted.


2019 ◽  
Vol 1 (1) ◽  
Author(s):  
Jiaqi Qin ◽  
Ci Wang ◽  
Leqi Wang ◽  
Shanshan Zhao ◽  
Jianguo Wu

AbstractRice viruses, known as “rice killer”, are vector-borne pathogens that cause severe disease and significant yield loss in rice production around the world. Rice virus disease is characterized by uncontrolled virus replication and the activation of host responses that contribute to pathogenesis. Underlying these phenomena is the potent suppression of rice antiviral responses, particularly the RNA silencing pathway and plant hormone pathways, which play vital roles in antiviral immunity. Classical rice virus disease control strategies include chemotherapeutics and use of disease resistance rice varieties. Here, we summarize recent advances in understanding the mechanisms behind the immune evasion and rice viral pathogenesis. Based on these mechanistic insights, we discuss how to combine different strategies for maintaining the effectiveness of rice resistance to viruses, and propose theoretical basis for the next generation of virus-resistant rice plants.


2013 ◽  
Vol 83 (2) ◽  
pp. 122-128 ◽  
Author(s):  
Cécile Renaud ◽  
Jacques Berger ◽  
Arnaud Laillou ◽  
Sylvie Avallone

Vitamin A deficiency is still one of the major public health problems in least developed countries. Fortification of vegetable oils is a strategy implemented worldwide to prevent this deficiency. For a fortification program to be effective, regular monitoring is necessary to control food quality in the producing units. The reference methods for vitamin A quantification are expensive and time-consuming. A rapid method should be useful for regular assessment of vitamin A in the oil industry. A portable device was compared to high-performance liquid chromatography (HPLC) for three plant oils (rapeseed, groundnut, and soya). The device presented a good linearity from 3 to 30 mg retinol equivalents per kg (mg RE.kg- 1). Its limits of detection and quantification were 3 mg RE.kg- 1 for groundnut and rapeseed oils and 4 mg RE.kg- 1 for soya oil. The intra-assay precision ranged from 1.48 % to 3.98 %, considered satisfactory. Accuracy estimated by the root mean squares error ranged from 3.99 to 5.49 and revealed a lower precision than HPLC (0.4 to 2.25). Although it offers less precision than HPLC, the device estimates quickly the vitamin A content of the tested oils from 3 or 4 to 15 mg RE.kg- 1.


2014 ◽  
Vol 84 (Supplement 1) ◽  
pp. 52-59 ◽  
Author(s):  
Sherry A. Tanumihardjo ◽  
Anura V. Kurpad ◽  
Janet R. Hunt

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.


2020 ◽  
Author(s):  
M Nagel ◽  
C Labenz ◽  
M Nguyen-Tat ◽  
N Cabezas Wallscheid ◽  
C Czauderna ◽  
...  

2015 ◽  
Vol 18 (3) ◽  
pp. 109
Author(s):  
Huseyin Saskin ◽  
Mustafa Idiz ◽  
Cagri Duzyol ◽  
Huseyin Macika ◽  
Rezan Aksoy

Pulmonary agenesis is associated with the absence of pulmonary vessels, bronchi, or parenchyma. This condition usually occurs between the 4th and 5th week of gestation during the embryonic phase. Etiopathogenic factors associated with pulmonary agenesis are not fully understood. In the literature, genetic and teratogenic factors, viral infections, and vitamin-A deficiency are shown to be associated with pulmonary agenesis [Malcon 2012]. This condition may be seen unilaterally or bilaterally. Although the precise rate of incidence is unknown, it is estimated to occur in one of every 10,000 to 12,000 live births [Yetim 2011]. There is a 1.3:1 female predominance with unilateral agenesis [Halilbasic 2013]


2018 ◽  
Vol 74 (1) ◽  
pp. 6029-2018
Author(s):  
HANDAN MERT ◽  
SERKAN YİLDİRİM ◽  
IBRAHİM HAKKİ YORUK ◽  
KİVANC IRAK ◽  
BAHAT COMBA ◽  
...  

Vitamins are essential for the health of all living organisms. Vitamins E, A, D and K are known as fat-soluble vitamins, and deprivation of vitamin E causes various disorders, especially in the reproduction and cardiovascular systems and in muscle functions. Vitamin A, on the other hand, has roles in various biological functions – like eyesight – and the growth, reproduction and differentiation of epithelial cells. Vitamin A deficiency leads to the keratinization of the epithelium, and disorders related to the metaplasies of the genital and genitourinary systems. Conversely, vitamin D is defined as a pro-hormone and is responsible for Cahomeostasis, and thus indirectly affects the bone metabolism, bone structure, and cellular and neural functions of Ca. White muscle disease (WMD) can occur in newborn lambs, but is more commonly seen in lambs of up to 3 months of age. In this study, 30 lambs of 3 to 50-days-old from different flocks diagnosed with White Muscle Disease (WMD) were selected as research material, while the control group consisted of 8 healthy lambs. With the aim of clarifying the cause of WMD, serum fat-soluble vitamins, retinol, α-tocopherol and vitamin D3 levels were determined in 16 lambs. Gluteal and heart musclet issue samples also were taken from 30 lambs with WMD. The vitamin levels of the samples were analysed by HPLC. The levels of serum α-tocopherol, retinols, and vitamin D3 were foundto be low in the diseased animals, but only retinol (p<0.001) and α-tocopherol (p<0.0011) level differences were statistically relevant. Macroscopically, Zenker’s necrosis was determined in the heart muscles of 17 lambs, and in the gluteal and chest muscles of 6 lambs. 7 lambs displayed necrosis in both their heart and in gluteal muscles. The samples were analyzed microscopically to reach similar findings: swollen homogeneous pink muscles, pycnotic nuclei, and hyperaemic and haemorrhagic blood vessels in gluteal, chest and heart muscles. Hyaline degeneration and Zenker's necrosis, dystrophic regions in necrotic areas, cc was detected as a severe disease in lambs at an early stage of life with advanced degeneration in different muscle tissues. Deficiency of fat-soluble vitamins was also detected in the sick animals. Control group lambs had higher levels of α tocopherol and retinol (p<0.001) compared to the sick lambs. .


2020 ◽  
Vol 18 ◽  
Author(s):  
Rina Das ◽  
Dinesh Kumar Mehta ◽  
Meenakshi Dhanawat

Abstract:: A novel virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), appeared and expanded globally by the end of year in 2019 from Wuhan, China, causing severe acute respiratory syndrome. During its initial stage, the disease was called the novel coronavirus (2019-nCoV). It was named COVID-19 by the World Health Organization (WHO) on 11 February 2020. The WHO declared worldwide the SARS-CoV-2 virus a pandemic on March 2020. On 30 January 2020 the first case of Corona Virus Disease 2019 (COVID-19) was reported in India. Now in current situation the virus is floating in almost every part of the province and rest of the globe. -: On the basis of novel published evidences, we efficiently summarized the reported work with reference to COVID-19 epidemiology, pathogen, clinical symptoms, treatment and prevention. Using several worldwide electronic scientific databases such as Pubmed, Medline, Embase, Science direct, Scopus, etc were utilized for extensive investigation of relevant literature. -: This review is written in the hope of encouraging the people successfully with the key learning points from the underway efforts to perceive and manage SARS-CoV-2, suggesting sailent points for expanding future research.


2005 ◽  
Vol 81 (2) ◽  
pp. 169-174 ◽  
Author(s):  
Ivan S. Ferraz ◽  
Júlio C. Daneluzzi ◽  
Hélio Vannucchi ◽  
Alceu A. Jordão Jr. ◽  
Rubens G. Ricco ◽  
...  

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