Physiological and biochemical changes induced in sunflower seeds by osmopriming and subsequent drying, storage and aging

1997 ◽  
Vol 7 (4) ◽  
pp. 323-332 ◽  
Author(s):  
M. Chojnowski ◽  
F. Corbineau ◽  
D. Côme
Keyword(s):  
Seed Viability ◽  
Accelerated Aging ◽  
Acc Oxidase ◽  
Significant Loss ◽  
Membrane Properties ◽  
Seed Vigour ◽  
Acc Conversion ◽  
Subsequent Storage ◽  
Polyethylene Glycol 6000

AbstractSunflower (Helianthus annuus L.) seeds show more germination at high temperatures (25–30°C) than at temperatures below 20°C. Osmopriming with polyethylene glycol-6000 for 3–5 days at 15°C strongly increases germination at suboptimal temperatures. This stimulatory effect of priming persists after seed redrying and during subsequent storage at 20°C (55% RH) for at least 14 weeks. However, primed seeds deteriorate faster than untreated seeds during accelerated aging (45°C, 100% RH). The longer the priming treatment, the higher is the amount of germination but at the same time the higher is the sensitivity of seeds to accelerated aging. Priming enhances the respiratory activity of seeds transferred onto water and their ability to convert 1-aminocyclopropane-1-carboxylic acid (ACC) to ethylene. These effects remain after drying the seeds and are maintained in part during dry storage, whereas they disappear during accelerated aging. These results suggest that ACC-dependent ethylene production might be a good indicator of seed vigour; it increases with duration of priming and decreases very early during aging, well before significant loss of seed viability. Decrease in ACC conversion to ethylene indicates that aging is probably associated with membrane deterioration since in vivo ACC oxidase activity depends on membrane properties. However, no increase in electrolyte leakage is observed during aging.

scholarly journals Vigour tests as indicators of seed viability

Genetika ◽  
2010 ◽  
Vol 42 (1) ◽  
pp. 103-118 ◽  
Author(s):  
Mirjana Milosevic ◽  
Milka Vujakovic ◽  
Djura Karagic
Keyword(s):  
Seed Quality ◽  
Growth Parameters ◽  
Seed Viability ◽  
Accelerated Aging ◽  
Cold Test ◽  
Plant Production ◽  
Biochemical Tests ◽  
Species Determination ◽  
Seed Vigour ◽  
Physiological Tests

Seed marks the beginning of each plant production and therefore ensuring its quality is the priority of modern seed science and a prerequisite for obtaining high yields of all plant species. Determination of seed quality and its viability indicates what seed lots can be placed onto the market, and for that reason it is very important to have reliable methods and tests to be used for seed quality and seed vigour testing. The term vigour of viability is used to describe the physiological characteristics of seeds that control its ability to germinate rapidly in the soil and to tolerate various, mostly negative environmental factors. MCDONALD grouped vigour tests into three groups: Physical tests - determine seed characteristics such as size and mass. These tests are inexpensive, quick, can be applied to large number of samples, and are positively correlated with seed vigour. The main feature of seed development is accumulation of nutritive materials, which is also in direct correlation with vigour, i.e. with size and mass of seed; Physiological tests - using germination and growth parameters. There are two types of these tests. First type, when germination is done under favourable conditions (standard laboratory germination, and test of growth intensity). Second type, when seed is exposed to unfavourable environmental conditions (cold test, accelerated aging test, and Hiltner test); Biochemical tests - are considered as indirect methods for estimation of seed value. These are Tetrazolijum test, conductometric measurements, enzyme activity and respiration.

scholarly journals Mfn2 Overexpression Attenuates MPTP Neurotoxicity In Vivo

2021 ◽  
Vol 22 (2) ◽  
pp. 601
Author(s):  
Fanpeng Zhao ◽  
Quillan Austria ◽  
Wenzhang Wang ◽  
Xiongwei Zhu
Keyword(s):  
Mitochondrial Dysfunction ◽  
Mitochondrial Dynamics ◽  
Significant Loss ◽  
Critical Event ◽  
Mitochondrial Fragmentation ◽  
Wild Type Littermate ◽  
Littermate Control ◽  
Mptp Administration

Mitochondrial dysfunction represents a critical event in the pathogenesis of Parkinson’s disease (PD). Increasing evidence demonstrates that disturbed mitochondrial dynamics and quality control play an important role in mitochondrial dysfunction in PD. Our previous study demonstrated that MPP+ induces mitochondrial fragmentation in vitro. In this study, we aimed to assess whether blocking MPTP-induced mitochondrial fragmentation by overexpressing Mfn2 affords neuroprotection in vivo. We found that the significant loss of dopaminergic neurons in the substantia nigra (SN) induced by MPTP treatment, as seen in wild-type littermate control mice, was almost completely blocked in mice overexpressing Mfn2 (hMfn2 mice). The dramatic reduction in dopamine neuronal fibers and dopamine levels in the striatum caused by MPTP administration was also partially inhibited in hMfn2 mice. MPTP-induced oxidative stress and inflammatory response in the SN and striatum were significantly alleviated in hMfn2 mice. The impairment of motor function caused by MPTP was also blocked in hMfn2 mice. Overall, our work demonstrates that restoration of mitochondrial dynamics by Mfn2 overexpression protects against neuronal toxicity in an MPTP-based PD mouse model, which supports the modulation of mitochondrial dynamics as a potential therapeutic target for PD treatment.

scholarly journals Aβ42 oligomers trigger synaptic loss through CAMKK2-AMPK-dependent effectors coordinating mitochondrial fission and mitophagy

2019 ◽  
Author(s):  
Annie Lee ◽  
Chandana Kondapalli ◽  
Daniel M. Virga ◽  
Tommy L. Lewis ◽  
So Yeon Koo ◽  
...  
Keyword(s):  
Genome Engineering ◽  
Pyramidal Neurons ◽  
Es Cells ◽  
Mitochondrial Fission ◽  
Significant Loss ◽  
Synaptic Loss ◽  
Structural Remodeling ◽  
Swedish Mutation ◽  
Human Neurons

AbstractDuring the early stages of Alzheimer’s disease (AD) in both mouse models and human patients, soluble forms of Amyloid-β1-42 oligomers (Aβ42o) trigger loss of excitatory synapses (synaptotoxicity) in cortical and hippocampal pyramidal neurons (PNs) prior to the formation of insoluble Aβ plaques. We observed a spatially restricted structural remodeling of mitochondria in the apical tufts of CA1 PNs dendrites in the hAPPSWE,IND transgenic AD mouse model (J20), corresponding to the dendritic domain receiving presynaptic inputs from the entorhinal cortex and where the earliest synaptic loss is detected in vivo. We also observed significant loss of mitochondrial biomass in human neurons derived from a new model of human ES cells where CRISPR-Cas9-mediated genome engineering was used to introduce the ‘Swedish’ mutation bi-allelically (APPSWE/SWE). Recent work uncovered that Aβ42o mediates synaptic loss by over-activating the CAMKK2-AMPK kinase dyad, and that AMPK is a central regulator of mitochondria homeostasis in non-neuronal cells. Here, we demonstrate that Aβ42o-dependent over-activation of CAMKK2-AMPK mediates synaptic loss through coordinated MFF-dependent mitochondrial fission and ULK2-dependent mitophagy in dendrites of PNs. We also found that the ability of Aβ42o-dependent mitochondrial remodeling to trigger synaptic loss requires the ability of AMPK to phosphorylate Tau on Serine 262. Our results uncover a unifying stress-response pathway triggered by Aβo and causally linking structural remodeling of dendritic mitochondria to synaptic loss.

Effects of norepinephrine upon superficial layer neurons in the superior colliculus of the hamster: In vitro studies

1999 ◽  
Vol 16 (3) ◽  
pp. 557-570 ◽  
Author(s):  
HONGJING TAN ◽  
RICHARD D. MOONEY ◽  
ROBERT W. RHOADES
Keyword(s):  
Superior Colliculus ◽  
Optic Tract ◽  
Reversal Potential ◽  
Outward Current ◽  
Input Resistance ◽  
Superficial Layer ◽  
Membrane Properties ◽  
Induced Response

Intracellular recording techniques were used to evaluate the effects of norepinephrine (NE) on the membrane properties of superficial layer (stratum griseum superficiale and stratum opticum) superior colliculus (SC) cells. Of the 207 cells tested, 44.4% (N = 92) were hyperpolarized by ≥3 mV and 8.7% (N = 18) were depolarized by ≥3 mV by application of NE. Hyperpolarization induced by NE was dose dependent (EC50 = 8.1 μM) and was associated with decreased input resistance and outward current which had a reversal potential of −94.0 mV. Depolarization was associated with a very slight rise in input resistance and had a reversal potential of −93.1 mV for the single cell tested. Pharmacologic experiments demonstrated that isoproterenol, dobutamine, and p-aminoclonidine all hyperpolarized SC cells. These results are consistent with the conclusion that NE-induced hyperpolarization of SC cells is mediated by both α2 and β1 adrenoceptors. The α1 adrenoceptor agonists, methoxamine and phenylephrine, depolarized 35% (6 of 17) of the SC cells tested by ≥3 mV. Most of the SC cells tested exhibited responses indicative of expression of more than one adrenoceptor. Application of p-aminoclonidine or dobutamine inhibited transsynaptic responses in SC cells evoked by electrical stimulation of optic tract axons. Inhibition of evoked responses by these agents was usually, but not invariably, associated with a hyperpolarization of the cell membrane and a reduction in depolarizing potentials evoked by application of glutamate. The present in vitro results are consistent with those of the companion in vivo study which suggested that NE-induced response suppression in superficial layer SC neurons was primarily postsynaptic and chiefly mediated by both α2 and β1 adrenoceptors.

A different fixation of the femoral component in total knee arthroplasty may lead to preservation of femoral bone stock

2003 ◽  
Vol 217 (5) ◽  
pp. 325-332 ◽  
Author(s):  
M Barink ◽  
N Verdonschot ◽  
M de Waal Malefijt
Keyword(s):  
Femoral Component ◽  
Knee Arthroplasty ◽  
Bone Remodelling ◽  
Significant Loss ◽  
Bone Stock ◽  
Femoral Bone ◽  
Secondary Effects ◽  
Total Knee ◽  
The Stability

Good femoral bone stock is important for the stability of the femoral component in revision knee arthroplasty. However, the primary total knee replacement (TKR) may cause significant loss of bone stock in the distal anterior femur. Earlier stress-induced bone remodelling simulations have suggested that a completely debonded component may save bone stock in the distal anterior region. However, these simulations did not consider the fixation of a debonded implant and possible secondary effects of micromotions and osteolysis at the interface. The current study tries to combine the preservation of bone stock with adequate component fixation. Different bone remodelling simulations were performed around femoral knee components with different sizes of bonding area and different friction characteristics of the debonded area. The fixation of the femoral component with different bonding characteristics is quantified with calculated implant-bone interface stresses. The results show that a bonded femoral component with a debonded inner side of the anterior flange may significantly reduce bone resorption in the endangered distal anterior femur, without jeopardizing the fixation of the femoral implant. This effect may be obtained in vivo by using a femoral component with a highly polished inner side of the anterior flange.

scholarly journals METABOLIC CONSEQUENCES OF METHIONINE REDOX IN METHIONINE RESTRICTION

2019 ◽  
Vol 3 (Supplement_1) ◽  
pp. S106-S107
Author(s):  
Kevin Thyne ◽  
Yuhong Liu ◽  
Adam B Salmon
Keyword(s):  
Protein Function ◽  
Methionine Sulfoxide ◽  
Redox Status ◽  
Significant Loss ◽  
Methionine Sulfoxide Reductase ◽  
Wild Type ◽  
Entire Family ◽  
Methionine Sulfoxide Reductase A ◽  
Methionine Restriction

Abstract While caloric restriction (CR) provides highly robust improvements to longevity and health, dietary restriction of the essential amino acid methionine can provide similar benefits including improved metabolic function and increased longevity. Despite these similarities between CR and methionine restriction (MR), there is growing evidence to suggest they may be mediated by different mechanisms that require further elucidation. The sulfur side-chain of methionine is highly prone to oxidation, even in vivo, with redox changes of these residues potentially altering protein function and interfering with its use as a substrate. An entire family of enzymes, methionine sulfoxide reductases, have evolved in aerobic organisms to regulate the redox status of methionine. We tested the role of methionine sulfoxide reductase A (MsrA) in the physiological and metabolic benefits of MR. After three months of MR, mice lacking MsrA (MsrA KO) showed significant loss of weight, including both fat and lean mass, in comparison to wild-type mice under MR. Both MsrA KO and wild-type mice responded to MR with improvements to both glucose and insulin tolerance. However, MR MsrA KO mice showed lower HbA1c and reduced leptin compared to MR wild-type mice. Overall, our results show mice lacking MsrA have a stronger response to MR suggesting that methionine redox may play an important role in some of the mechanisms responsible for these metabolic outcomes. Further studies clarify whether MsrA could also be a potential regulator of the longevity benefits of MR.

Effect of NPK on growth, yield and seed quality of hybrid Chilli

2019 ◽  
Vol 9 (1) ◽  
pp. 35-41
Author(s):  
M Hasan ◽  
M Robbani ◽  
R Parvin ◽  
MNH Mehedi ◽  
I Hossain
Keyword(s):  
Seed Yield ◽  
Seed Quality ◽  
Seed Viability ◽  
Growth Yield ◽  
Control Treatment ◽  
Npk Fertilizers ◽  
Seed Vigour ◽  
Female Line ◽  
Long Time

An experiment was carried out at Germplasm Centre and Plant Biotechnology Lab, Department of Horticulture, PSTU to evaluate the growth, seed yield and quality of hybrid F1 chilli (cv. Sonic) crossing male line (LTSL-004-M) and female line (LTSL-004-F) along the viability of productive seeds influenced by NPK fertilizers during the period from November 2015 to October 2016. Ten different treatments of NPK fertilizers were used. Result showed that all the characteristics except primary branches and1000 seed weight were influenced significantly due to the application of NPK fertilizers. The tallest plant (69.88 cm), more leaves plant–1 (2491.33), highest number of secondary branches plant-1, tertiary branches plant-1 (5.00 and 88.00, respectively), number of flowers and hybrid fruits plant–1 (1533.00 and 12.33, respectively) and weight of seeds (4.03 g plant–1) along with required more time (54.67 days) for flowering were obtained from the application of 145 kg N ha–1, 175 kg P ha–1 and 96 kg K ha–1 (T4) which produced the highest final seed yield of chilli (4.03 kg ha–1). Application of T5 and T9 showed the highest number of primary branches (2.33). In seed viability characteristics T9 treated seeds showed the highest germination (100, 97.33 and 94.97%) at 1st, (1 MAH - Month After Harvest), 2nd (2 MAH) and 3rd (4 MAH) observations, respectively. The T3 treated seeds performed well in respect of Seed Vigour Index (SVI) at 1st and 2nd observations (8.00 and 7.48, respectively) but T9 treated seeds showed the highest SVI (6.32) at 3rd observation. Above indicating all characteristics were lowest under only recommended doses of NPK T1 as control treatment except days to first flowering. The observations suggested that production of hybrid chilli seeds could be enhanced by applying T4. While seeds of chilli treated by T9 in field level showed long time viable. Application of 145 kg N ha–1, 175 kg P ha–1 and 96 kg K ha–1 may be suggested for seed production of chilli and 110 kg N ha–1, + 175 kg P ha–1 + 115 kg K ha–1 for keeping the long time seed viability. Int. J. Agril. Res. Innov. & Tech. 9 (1): 35-41, June, 2019

scholarly journals Functional Crosstalk between CB and TRPV1 Receptors Protects Nigrostriatal Dopaminergic Neurons in the MPTP Model of Parkinson’s Disease

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Rayul Wi ◽  
Young Cheul Chung ◽  
Byung Kwan Jin ◽  
Lihua Duan
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Significant Loss ◽  
Glial Activation ◽  
Dopamine Neurons ◽  
Pcr Analysis ◽  
Beneficial Effects ◽  
Nigrostriatal Dopamine ◽  
Nigrostriatal Dopamine Neurons

The present study examined whether crosstalk between cannabinoid (CB) and transient potential receptor vanilloid type 1 (TRPV1) could contribute to the survival of nigrostriatal dopamine neurons in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of Parkinson’s disease (PD). MPTP induced a significant loss of nigrostriatal dopamine neurons and glial activation in the substantia nigra (SN) and striatum (STR) as visualized by tyrosine hydroxylase (TH) or macrophage antigen complex-1 (MAC-1) or glial fibrillary acidic protein (GFAP) immunocytochemistry, respectively. RT-PCR analysis shows the upregulation of inducible nitric oxide synthase, interleukin-1β, and tumor necrosis factor-α in microglia in the SN in vivo, indicating the activation of the inflammatory system. By contrast, treatment with capsaicin (a specific TRPV1 agonist) increased the survival of dopamine neurons in the SN and their fibers and dopamine levels in the STR in MPTP mice. Capsaicin neuroprotection is accompanied by inhibiting MPTP-induced glial activation and production of inflammatory cytokines. Treatment with AM251 and AM630 (CB1/2 antagonists) abolished capsaicin-induced beneficial effects, indicating the existence of a functional crosstalk between CB and TRPV1. Moreover, treatment with anandamide (an endogenous agonist for both CB and TRVP1) rescued nigrostriatal dopamine neurons and reduced gliosis-derived neuroinflammatory responses in MPTP mice. These results suggest that the cannabinoid and vanilloid system may be beneficial for the treatment of neurodegenerative diseases, such as PD, that are associated with neuroinflammation.

Dendritic arbor of locus coeruleus neurons contributes to opioid inhibition

1996 ◽  
Vol 75 (5) ◽  
pp. 2029-2035 ◽  
Author(s):  
R. A. Travagli ◽  
M. Wessendorf ◽  
J. T. Williams
Keyword(s):  
Locus Coeruleus ◽  
Horizontal Plane ◽  
Reversal Potential ◽  
Outward Current ◽  
Membrane Properties ◽  
Equilibrium Potential ◽  
Intrinsic Membrane Properties ◽  
In Cells

1. The nucleus locus coeruleus (LC) is made up of noradrenergic cells all of which are hyperpolarized by opioids. Recent work has shown that the reversal potential of the opioid-induced current is more negative than the potassium equilibrium potential. The aim of the present study was to determine whether the extent of the dendritic field could contribute to the very negative opioid reversal potential. 2. Individual LC cells were labeled in the brain slice preparation. The number of dendrites found on cells in slices sectioned in the horizontal plane was greater than cells in coronal slices. However, the dimensions of the cell body slices from each plane were not significantly different. 3. The resting conductance of neurons from slices cut in the horizontal plane was significantly larger than in cells from coronal plane. 4. The amplitude of the outward current induced by [Met5]-enkephalin (ME) was larger in cells from horizontal slices and the reversal potential was more negative than that of cells in coronal slices. 5. The results show that the plane of section influences the membrane properties and opioid actions of LC neurons in vitro and suggest that these differences correlate with the numbers of dendrites. The results suggest that in vivo, in addition to intrinsic membrane properties and synaptic inputs, the structural makeup of the nucleus is an important factor in determining the activity.

scholarly journals Phenotypic aberrations during micropropagation of Soymida febrifuga (Roxb.) Adr. Juss

2014 ◽  
Vol 6 (1) ◽  
pp. 99-104 ◽  
Author(s):  
Kishore Kumar CHIRUVELLA ◽  
Arifullah MOHAMMED ◽  
Rama Gopal GHANTA
Keyword(s):  
Seed Viability ◽  
Ms Medium ◽  
Stem Cuttings ◽  
Endemic Plant ◽  
Seedling Mortality ◽  
Root Regeneration ◽  
Half Strength ◽  
Shoot Necrosis

Like most of the medicinal plants Soymida febrifuga (Meliaceae) possess significance for its valuable secondary metabolites. Multiplication of this endemic plant is limited by difficulty in rooting of stem cuttings, high seedling mortality rates and low seed viability period. Hence efficient protocols for in vitro mass propagation has been established from field grown and aseptic seedlings explants. Strikingly, we observed aberrant structures such as vitrified shoots, faciated shoots, albino shoots as well shoot necrosis during its micropropagation. These phenotypic maladies were observed during organogenesis and rooting. Compared to other abnormalities, shoot necrosis nonetheless was frequent and pronounced leading to plant death. Shoots when subjected to rooting also displayed necrosis which was controlled by transferring to MS medium containing various concentrations and combinations of calcium levels, activated charcoal, glucose, fructose and auxins. Microshoots initiated roots on half strength MS medium with IBA and IAA individually or in combination within two weeks. MS half strength solid medium supplemented with CAN (556 mg l–1), CAP (1.0 mg l–1), IAA (2.0 mg l–1) and IBA (2.0 mg l–1) in combination was found to be more efficient in showing high frequency (95%) of root regeneration. Rooted plantlets were successfully hardened and 70-85% of regenerated plants were successfully acclimatized to natural environment. In vitro derived plantlets were morphologically similar to in vivo plants.

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