scholarly journals NaCl Promotes the Efficient Formation of Haematococcus pluvialis Nonmotile Cells under Phosphorus Deficiency

Marine Drugs ◽  
2021 ◽  
Vol 19 (6) ◽  
pp. 337
Author(s):  
Feng Li ◽  
Ning Zhang ◽  
Yulei Zhang ◽  
Qingsheng Lian ◽  
Caiying Qin ◽  
...  
Keyword(s):  
Haematococcus Pluvialis ◽  
Phosphorus Deficiency ◽  
Cell Formation ◽  
Animal Nutrition ◽  
Cell Factory ◽  
Cell Type ◽  
Negative Effects ◽  
Related Factors ◽  
Motile Cells ◽  
Application Prospects

Natural astaxanthin helps reduce the negative effects caused by oxidative stress and other related factors, thereby minimizing oxidative damage. Therefore, it has considerable potential and broad application prospects in human health and animal nutrition. Haematococcus pluvialis is considered to be the most promising cell factory for the production of natural astaxanthin. Previous studies have confirmed that nonmotile cells of H. pluvialis are more tolerant to high intensity of light than motile cells. Cultivating nonmotile cells as the dominant cell type in the red stage can significantly increase the overall astaxanthin productivity. However, we know very little about how to induce nonmotile cell formation. In this work, we first investigated the effect of phosphorus deficiency on the formation of nonmotile cells of H. pluvialis, and then investigated the effect of NaCl on the formation of nonmotile cells under the conditions of phosphorus deficiency. The results showed that, after three days of treatment with 0.1% NaCl under phosphorus deficiency, more than 80% of motile cells had been transformed into nonmotile cells. The work provides the most efficient method for the cultivation of H. pluvialis nonmotile cells so far, and it significantly improves the production of H. pluvialis astaxanthin.

The conserved ninth C-terminal heptad in thyroid hormone and retinoic acid receptors mediates diverse responses by affecting heterodimer but not homodimer formation

1993 ◽  
Vol 13 (9) ◽  
pp. 5725-5737
Author(s):  
M Au-Fliegner ◽  
E Helmer ◽  
J Casanova ◽  
B M Raaka ◽  
H H Samuels
Keyword(s):  
Retinoic Acid ◽  
Thyroid Hormone ◽  
Dominant Negative ◽  
Heptad Repeat ◽  
Specific Response ◽  
Wild Type ◽  
Negative Effects ◽  
Related Factors ◽  
Response Element ◽  
Response Elements

The receptors for thyroid hormone (T3R), all-trans-retinoic acid (RAR), and 9-cis-retinoic acid (RXR) bind DNA response elements as homo- and heterodimers. The ligand-binding domains of these receptors contain nine conserved heptads proposed to play a role in dimerization. Mutant receptors with changes in the first or last hydrophobic amino acids in the highly conserved ninth heptad of chick T3R alpha [cT3R alpha(L365R) and cT3R(L372R)] and human RAR alpha (hRAR alpha) [hRAR(M377R) and hRAR(L384R)] reveal that this heptad is essential for certain heterodimeric interactions and for diverse functional activities. Without ligands, wild-type receptors form both homodimers and heterodimers, while these mutants form only homodimers. Surprisingly, the cognate ligand for each mutant enables heterodimer formation between cT3R(L365R) and RAR or RXR and between hRAR(M377R) and T3R or RXR. Both cT3R(L365R) and hRAR(M377R) mediate ligand-dependent transcriptional regulation. However, unlike the wild-type receptor, non-ligand-associated cT3R(L365R) does not suppress the basal activity of certain promoters containing thyroid hormone response elements, suggesting that this silencing effect of T3R is mediated by unliganded heterodimers of T3R and endogenous RXR or related factors. Heterodimerization is also necessary for the strong ligand-independent inhibition between T3R and RAR on a common response element, since the ninth-heptad mutants function as poor inhibitors. However, with a T3R-specific response element, hRAR(M377R) acts as a retinoic acid-dependent inhibitor of cT3R, indicating the importance of heterodimerization for this inhibition. Our studies also suggest that the ninth heptad is necessary for the dominant inhibition of wild-type T3Rs by mutant T3Rs, as has been found for the thyroid hormone-resistant syndrome in humans. Thus, the ninth heptad repeat is required for heterodimerization, suppression of basal promoter activity, and dominant negative effects of T3R and RAR. Lastly, the finding that cT3R(L365R) and hRAR(M377R) require ligands for heterodimer formation also raises the possibility that heterodimeric interactions are mediated by the ninth heptad without ligands but by a second region of these receptors with ligands.

scholarly journals Potential for application of feed additives encapsulation technology in animal nutrition

Krmiva ◽  
2021 ◽  
Vol 62 (1) ◽  
pp. 57-66
Author(s):  
Sara Kolar ◽  
Slaven Jurić ◽  
Kristina Vlahoviček-Kahlina ◽  
Marko Vinceković
Keyword(s):  
Targeted Delivery ◽  
Animal Health ◽  
Correct Choice ◽  
Feed Additives ◽  
Animal Nutrition ◽  
Growth Promoters ◽  
Negative Effects ◽  
Animal Growth ◽  
Enhancing Production ◽  
Positive Effect

Demands for higher production and consumer demand for healthier food have encouraged intensive research for alternative animal growth promoters in recent years. Research trends are focused on the development of new products enriched with feed additives to improve animal health and enhancing production. Many of these compounds are unstable in the presence of light, air, water, or high temperatures and need to be protected during processing, storage, and application. By encapsulatied in microparticles, feed additives are protected from harmful external influences, and their stability and functionality are not diminished. Microencapsulation technology is used to protect payload and improve bioavailability by controlled and targeted delivery to the digestive tract. It is particularly suitable for the addition of feed additives in ruminant’s nutrition, because the correct choice of microparticle material allows the release of the feed additives in the small intestine, and not in the rumen. With proper use, microparticle formulations are an effective tool in animal nutrition that delivers nutrients and/or drugs to a specific site at the desired rate. The paper summarizes laboratory studies on the application of microencapsulation technology in feeding ruminants and monogastric animals. Numerous results of the application of encapsulated feed additives have shown a positive effect on animal health, increased productivity without negative effects on the final product, and environmental protection.

scholarly journals Relation of Polypharmacy to Systemic and Oral Health Related Factors

2018 ◽  
Vol 69 (11) ◽  
pp. 3115-3117
Author(s):  
Madalina Bicheru ◽  
Cristina Teodora Preoteasa ◽  
Andreea Zamfirescu ◽  
Ana Capisizu ◽  
Marina Melescanu Imre ◽  
...  
Keyword(s):  
Oral Health ◽  
Cross Sectional Study ◽  
Prescription Medications ◽  
Negative Effects ◽  
Related Factors ◽  
Cross Sectional ◽  
Convenience Sample ◽  
Health Related ◽  
Removable Prosthesis ◽  
Systemic Health

To assess polypharmacy (i.e., multiple medication use, as synthetic chemical products) and its relationship to general, systemic health and oral health factors in adults over 50 years old. A cross-sectional study was conducted on a convenience sample of adult patients recruited from two medical centers from Bucharest, i.e. from the Clinic of Dental Prosthetics, Carol Davila University of Medicine and Pharmacy, and from Saint Luca Hospital for Chronic Diseases. Study sample included 126 patients, that used a mean of 5.2 drugs. Almost half of patients (43.65%) used more than five prescribed medications. There was a tendency to use a greater number of medications in the case of patients that were hospitalized at Saint Luca Hospital, were less educated, had a lower income, had a greater number of comorbidities, had untreated edentulism in both jaws, were unfrequently wearing removable prosthesis and were using denture adhesives. Both positive and negative effects of polypharmacy should be considered in mutimorbidity patients when establishing prescription medications, along with general and oral factors that may influence treatment conduct and outcome.

Cell-type-dependent gene activation by yeast transposon Ty1 involves multiple regulatory determinants

1987 ◽  
Vol 7 (9) ◽  
pp. 3205-3211
Author(s):  
M Company ◽  
B Errede
Keyword(s):  
Gene Expression ◽  
Transcriptional Control ◽  
Gene Activation ◽  
Distal Region ◽  
Control Site ◽  
Cell Type ◽  
Cell Type Specificity ◽  
Negative Effects ◽  
Cis Acting ◽  
Transcriptional Control Region

Ty transposable element insertion mutations of Saccharomyces cerevisiae can cause cell-type-dependent activation of adjacent gene expression. Several cis-acting regulatory regions within Ty1 that are responsible for these effects were identified. A 211-base-pair (bp) region functions as an activator. This region includes the so-called U5 domain of delta and 145 bp of adjacent epsilon sequences. Unlike activation by the intact Ty1, activation by the 211-bp Ty1 subfragment is cell-type independent. The presence of a 112-bp fragment from a more distal region of Ty1 confers cell-type specificity to the activator. The 112-bp fragment includes sequences with homology to mammalian enhancers and to a yeast a/alpha control site. In addition, Ty1 regions that exert negative effects on gene expression were identified. These results demonstrate that the Ty1 transcriptional control region consists of multiple components with distinct regulatory functions.

Implementation of a targeted mastitis therapy concept using an on-farm rapid test: antimicrobial consumption, cure rates and compliance

2020 ◽  
Vol 187 (10) ◽  
pp. 401-401 ◽  
Author(s):  
Anne Schmenger ◽  
Stefanie Leimbach ◽  
Nicole Wente ◽  
Yanchao Zhang ◽  
Andrew Martin Biggs ◽  
...  
Keyword(s):  
Relapse Rate ◽  
Treatment Approach ◽  
Real Life ◽  
Rapid Test ◽  
Clinical Mastitis ◽  
Negative Effects ◽  
Related Factors ◽  
Treatment Groups ◽  
Cure Rates ◽  
On Farm

BackgroundAim of the present study was to investigate the implementation of a targeted therapy (tLCT) concept under real-life circumstances, taking both pathogen-related and animal-related factors into account. The reduction of antibiotics without negative effects on cure rates was evaluated as well as the compliance by the farmers.MethodsAfter analysing the existing conventional therapy (CT) concepts of five farms, the tLCT concept and a novel on-farm test were introduced. Three treatment groups were compared with respect to bacteriological cure (BC), cytological cure (CYC), full cure (FC), new infection rate (NIR), relapse rate and the treatment approach per mastitis case: the CT group, the tLCT group including all clinical mastitis (CM) cases treated according to the concept, and the modified tLCT group (tLCTmod), including the CM cases in which farmers deviated from the concept.ResultsEven so farmers deviated from the treatment concept in 506 out of 909 cases; belonging to one of the three treatment groups had no significant impact on BC, CYC, FC, NIR or relapse rate. The antibiotic usage in the tLCT as well as in the tLCTmod group was significantly lower in comparison to the CT group.ConclusionFrom this, it can be deduced that farmers will reduce antibiotic doses by implementing a tLCT concept.

scholarly journals Cell-type-dependent gene activation by yeast transposon Ty1 involves multiple regulatory determinants.

1987 ◽  
Vol 7 (9) ◽  
pp. 3205-3211 ◽  
Author(s):  
M Company ◽  
B Errede
Keyword(s):  
Gene Expression ◽  
Transcriptional Control ◽  
Gene Activation ◽  
Distal Region ◽  
Control Site ◽  
Cell Type ◽  
Cell Type Specificity ◽  
Negative Effects ◽  
Cis Acting ◽  
Transcriptional Control Region

Ty transposable element insertion mutations of Saccharomyces cerevisiae can cause cell-type-dependent activation of adjacent gene expression. Several cis-acting regulatory regions within Ty1 that are responsible for these effects were identified. A 211-base-pair (bp) region functions as an activator. This region includes the so-called U5 domain of delta and 145 bp of adjacent epsilon sequences. Unlike activation by the intact Ty1, activation by the 211-bp Ty1 subfragment is cell-type independent. The presence of a 112-bp fragment from a more distal region of Ty1 confers cell-type specificity to the activator. The 112-bp fragment includes sequences with homology to mammalian enhancers and to a yeast a/alpha control site. In addition, Ty1 regions that exert negative effects on gene expression were identified. These results demonstrate that the Ty1 transcriptional control region consists of multiple components with distinct regulatory functions.

scholarly journals The pigment composition of Haematococcus pluvialis microalgae cells upon cultivated on biogenic-deficient media

2020 ◽  
Vol 65 (2) ◽  
pp. 163-170
Author(s):  
N. V. Shalygo
Keyword(s):  
Chlorophyll A ◽  
Nutrient Medium ◽  
Haematococcus Pluvialis ◽  
Phosphorus Deficiency ◽  
Nitrogen Deficiency ◽  
Control Level ◽  
Pigment Composition ◽  
Nutrient Media ◽  
P Deficiency ◽  
Β Carotene

The accumulation of carotenoids (carotenogenesis) in the cells of Haematococcus pluvialis (strain IBCE H-17) upon cultivation in nutrient media deficient in nutrient elements (N and K + P) is shown. K and P deficiency in nutrient medium led to accumulation of astaxanthin, β-carotene, anteraxanthin, zeaxanthin and violaxanthin after 18 days of cultivation, while the amount of neoxanthin and lutein was at the control level. Carotenogenesis under such conditions was accompanied by high levels of chlorophyll (a + b). The use of nutrient medium deficient in N led to the accumulation of astaxanthin and, to a lesser extent, β-carotene in haematococcus cells, while lutein, anteraxanthin, zeaxanthin, violaxanthin and neoxanthin levels were lower or the same as control. N deficiency caused the decrease in amount of chlorophyll (a + b). Nitrogen deficiency was 4.3 times more effective than control medium and 1.8 times more effective than combined potassium and phosphorus deficiency in promoting astaxanthin accumulation.

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