Responses of Detached Rice Leaves (Oryza sativa L.) To Moderate Supplementary Ultraviolet-B Radiation Allow Early Screening for Relative Sensitivity to Ultraviolet-B Irradiation

1993 ◽  
Vol 20 (3) ◽  
pp. 285 ◽  
Author(s):  
LK Huang ◽  
J He ◽  
WS Chow ◽  
MI Whitecross ◽  
JM Anderson
Keyword(s):  
Oryza Sativa L ◽  
Relative Sensitivity ◽  
Ultraviolet B ◽  
Total Soluble Protein ◽  
Rice Cultivars ◽  
Short Term ◽  
Early Screening ◽  
Short Term Treatment ◽  
Detached Leaves ◽  
Rice Leaves

Responses to short-term supplementary ultraviolet-B (UV-B) radiation were studied in detached leaves of two indica rice cultivars (Er Bai Ai and Lemont) to evaluate whether this might be an initial method for screening for UV-B susceptibility. Leaf tissue from plants grown in a greenhouse (28�C day/ 20�C night, with a maximum irradiance of 800-1000 μmol photons m-2 s-1) was placed under moderate supplementary UV-B radiation for 20 h. The effects of this short-term treatment were measured by determining the ratio of variable to maximum chlorophyll fluorescence (Fv/Fm), quantum yield of photosynthetic O2 exchange, chlorophyll content, maximum Rubisco activity as well as the concentrations of total soluble protein and Rubisco protein. All the above parameters showed considerable declines, which were always greater in cv. Er Bai Ai than in cv. Lemont. The in vivo activation of Rubisco was markedly increased in detached leaves treated with supplementary UV-B compared with control leaves; the increase was greater in cv. Er Bai Ai than in cv. Lemont. The photosynthetic responses invoked in the detached rice leaves are remarkably similar to those observed previously [He et al. (1993). Aust. J. Plant Physiol. 20, 129-42] in intact rice plants which had a longer-term supplementary UV-B exposure of comparable cumulative biologically effective UV-B dosage. We conclude that rapid short-term responses of detached leaves allow early screening of relative sensitivity of rice cultivars to UV-B.

Responses of Rice and Pea Plants to Hardening With Low Doses of Ultraviolet-B Radiation

1994 ◽  
Vol 21 (5) ◽  
pp. 563 ◽  
Author(s):  
J He ◽  
LK Huang ◽  
WS Chow ◽  
MI Whitecross ◽  
JM Anderson
Keyword(s):  
Oryza Sativa L ◽  
Photosynthetic Apparatus ◽  
Ultraviolet B ◽  
Water Soluble ◽  
Rice Cultivars ◽  
Unit Leaf ◽  
Hardening Treatment ◽  
Uv Absorbing Compounds ◽  
Soluble Enzymes ◽  
Photosynthetic Properties

Responses of two rice cultivars (Oryza sativa L. cw. Er Bai Ai and Lemont) and a pea plant (Pisum sativum L. cv. Greenfeast) to low daily doses of ultraviolet-B (UV-B) radiation were measured to explore mechanisms underlying UV-B tolerance. On hardening of rice plants, cv. Er Bai Ai produced more UV-absorbing compounds than cv. Lemont; however, cv. Lemont produced more water-soluble proteins, which may be related to its greater UV-B tolerance. These responses occurred without apparent deleterious effects on the photosynthetic properties of rice leaves. In contrast, the same hardening doses caused damage to pea plants, as indicated by decreases in photosynthetic quantum yield, maximum photosynthetic capacity and chlorophyll content per unit leaf area, as well as water-soluble and total protein contents. The acquired tolerance of the two rice cultivars to a subsequent high UV-B dose increased with the duration of the hardening treatment. In contrast, the 'hardening' treatment exacerbated the damage to the photosynthetic apparatus of pea plants subsequently exposed to a high UV-B dose. It appears that for defence against UV-B radiation, cv. Er Bai Ai relies more upon the synthesis of UV-absorbing compounds, while cv. Lemont depends more upon the synthesis of protective, water-soluble enzymes; however, neither strategy seems to operate effectively in pea plants.

A Newspaper’s Effect on the Strength of Automatic Associations in Memory

2012 ◽  
Vol 24 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Florian Arendt
Keyword(s):  
Treatment Group ◽  
Term Effect ◽  
Control Group ◽  
Implicit Measure ◽  
Short Term ◽  
Short Term Treatment ◽  
Short Term Effect ◽  
Automatic Associations ◽  
Foreign Nationality ◽  
The Impact

A test was done to see if reading a newspaper which consistently overrepresents foreigners as criminals strengthens the automatic association between foreign country and criminal in memory (i.e., implicit cultivation). Further, an investigation was done to find out if reading articles from the same newspaper produces a short-term effect on the same measure and if (1) emotionalization of the newspaper texts, (2) emotional reactions of the reader (indicated by arousal), and (3) attributed text credibility moderate the short-term treatment effect. Eighty-five participants were assigned to one of three experimental conditions. Participants in the control group received short factual crime texts, where the nationality of the offender was not mentioned. Participants in the factual treatment group received the same texts, but the foreign nationality was mentioned. Participants in the emotionalized treatment group received emotionalized articles (i.e., texts which are high in vividness and frequency) covering the same crimes, with the foreign nationality mentioned. Supporting empirical evidence for implicit cultivation and a short-term effect was found. However, only emotionalized articles produced a short-term effect on the strength of the automatic association, indicating that newspaper texts must have a minimum of stimulus intensity to overcome an effect threshold. There were no moderating effects of arousal or credibility pertaining to the impact on the implicit measure. However, credibility moderated the short-term effect on a first-order judgment (i.e., estimated frequency of foreigners of all criminals). This indicates that a newspaper’s effect on the strength of automatic associations is relatively independent from processes of propositional reasoning.

Sensitivity of Selected Vegetable and Weed Seedlings to Ultraviolet-B Radiation

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 480e-480
Author(s):  
Nancy H. Furness ◽  
Mahesh K. Upadhyaya ◽  
Douglas P. Ormrod
Keyword(s):  
Brassica Oleracea ◽  
Leaf Area ◽  
Spinacia Oleracea ◽  
Relative Sensitivity ◽  
Amaranthus Retroflexus ◽  
Ultraviolet B ◽  
Seedling Height ◽  
Fresh Weight ◽  
Stellaria Media ◽  
Green Foxtail

Relative sensitivity of selected vegetable and weed seedlings to ultraviolet-B (UV-B) radiation (280–320 nm) was investigated. Seedlings were grown for 4 weeks in a greenhouse, in chambers equipped with UV-B-emitting fluorescent tubes and Mylar (control) and cellulose acetate (UV-B) filters. UV-B radiation reduced seedling height, leaf area, and leaf fresh weight in tomato (Lycopersicon esculentum `Cour Di Bue'), broccoli (Brassica oleracea var. Italica `Purple Sprouting'), cabbage (Brassica oleracea var. Capitata `Red Drumhead'), and cucumber (Cucumis sativus `Straight Eight'), leaf area and leaf fresh weight in beet (Beta vulgaris `Cylindra' and `Early Wonder'), seedling height and leaf area in spinach (Spinacia oleracea `Long Standing Bloomsdale'), lettuce (Lactuca sativa ``Red Salad Bowl Everest') and `Savoy' cabbage, and seedling height in `Chinese Tip Top' cabbage and lettuce (`Saladin'). `Winterton' cabbage was not affected. UV-B radiation decreased leaf area and leaf fresh weight in common chickweed (Stellaria media) and corn spurry (Spergula arvensis) and seedling height in green foxtail (Setaria viridis) and redroot pigweed (Amaranthus retroflexus). Tillering was stimulated in response to UV-B in green foxtail. There was no effect of UV-B on lady's-thumb (Polygonum persicaria) growth. Leaf number was not affected by exposure to UV-B in any species. The differential morphological sensitivity of vegetable and weed seedlings may result in altered competitive relationships under enhanced UV-B levels expected with the depletion of the earth's ozone layer.

scholarly journals The role of KPI-121 0.25% in the treatment of dry eye disease: penetrating the mucus barrier to treat periodic flares

2021 ◽  
Vol 13 ◽  
pp. 251584142110127
Author(s):  
Preeya K. Gupta ◽  
Nandini Venkateswaran
Keyword(s):  
Drug Delivery ◽  
Dry Eye ◽  
Ocular Surface ◽  
Dry Eye Disease ◽  
Eye Disease ◽  
Eye Drops ◽  
Short Term ◽  
Short Term Treatment ◽  
Loteprednol Etabonate ◽  
Mucus Barrier

The tear film, which includes mucins that adhere to foreign particles, rapidly clears allergens and pathogens from the ocular surface, protecting the underlying tissues. However, the tear film’s ability to efficiently remove foreign particles during blinking can also pose challenges for topical drug delivery, as traditional eye drops (solutions and suspensions) are cleared from the ocular surface before the drug can penetrate into the conjunctival and corneal epithelium. In the past 15 years, there has been an increase in the development of nanoparticles with specialized coatings that have reduced affinity to mucins and are small enough in size to pass through the mucus barrier. These mucus-penetrating particles (MPPs) have been shown to efficiently penetrate the mucus barrier and reach the ocular surface tissues. Dry eye disease (DED) is a common inflammatory ocular surface disorder that often presents with periodic flares (exacerbations). However, currently approved immunomodulatory treatments for DED are intended for long-term use. Thus, there is a need for effective short-term treatments that can address intermittent flares of DED. Loteprednol etabonate, an ocular corticosteroid, was engineered to break down rapidly after administration to the ocular surface tissues and thereby reduce risks associated with other topical steroids. KPI-121 is an ophthalmic suspension that uses the MPP technology to deliver loteprednol etabonate more efficiently to the ocular tissues, achieving in animal models a 3.6-fold greater penetration of loteprednol etabonate to the cornea than traditional loteprednol etabonate ophthalmic suspensions. In clinical trials, short-term treatment with KPI-121 0.25% significantly reduced signs and symptoms of DED compared with its vehicle (placebo). Recently approved KPI-121 0.25%, with its novel drug delivery design and ease of use, has the potential to effectively treat periodic flares of DED experienced by many patients.

scholarly journals A meta-analysis comparing short-term weight and cardiometabolic changes between olanzapine/samidorphan and olanzapine

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Manit Srisurapanont ◽  
Sirijit Suttajit ◽  
Surinporn Likhitsathian ◽  
Benchalak Maneeton ◽  
Narong Maneeton
Keyword(s):  
Weight Gain ◽  
Meta Analysis ◽  
Random Effect ◽  
Random Effect Model ◽  
Dropout Rates ◽  
Lower Percentage ◽  
Current Evidence ◽  
Weight Changes ◽  
Short Term ◽  
Short Term Treatment

AbstractThis study compared weight and cardiometabolic changes after short-term treatment of olanzapine/samidorphan and olanzapine. Eligible criteria for an included trial were ≤ 24 weeks, randomized controlled trials (RCTs) that compared olanzapine/samidorphan and olanzapine treatments in patients/healthy volunteers and reported weight or cardiometabolic outcomes. Three databases were searched on October 31, 2020. Primary outcomes included weight changes and all-cause dropout rates. Standardized mean differences (SMDs) and risk ratios (RRs) were computed and pooled using a random-effect model. This meta-analysis included four RCTs (n = 1195). The heterogeneous data revealed that weight changes were not significantly different between olanzapine/samidorphan and olanzapine groups (4 RCTs, SDM = − 0.19, 95% CI − 0.45 to 0.07, I2 = 75%). The whole-sample, pooled RR of all-cause dropout rates (4 RCTs, RR = 1.02, 95% CI 0.84 to 1.23, I2 = 0%) was not significant different between olanzapine/samidorphan and olanzapine groups. A lower percentage of males and a lower initial body mass index were associated with the greater effect of samidorphan in preventing olanzapine-induced weight gain. Current evidence is insufficient to support the use of samidorphan to prevent olanzapine-induced weight gain and olanzapine-induced cardiometabolic abnormalities. Samidorphan is well accepted by olanzapine-treated patients.

Amorphous silica nanoparticles induced spleen and liver toxicity after acute intravenous exposure in male and female rats

2021 ◽  
pp. 074823372110105
Author(s):  
Roberta Tassinari ◽  
Andrea Martinelli ◽  
Mauro Valeri ◽  
Francesca Maranghi
Keyword(s):  
Amorphous Silica ◽  
Liver Toxicity ◽  
Female Rats ◽  
Histopathological Analysis ◽  
Short Term ◽  
Short Term Treatment ◽  
Male And Female ◽  
Male And Female Rats ◽  
Target Organs ◽  
Short Term Exposure

Synthetic amorphous silica (SAS) nanomaterial – consisting of aggregates and agglomerates of primary silicon dioxide (SiO2) particles in the nanorange (<100 nm) – is commonly used as excipient in pharmaceuticals, in cosmetics and as food additive (E551). The available data suggest that SAS nanoparticles (NP) after intravenous (IV) exposure persist in liver and spleen; however, insufficient data exist to verify whether SAS may also induce adverse effects. The aim of the present study was to verify the potential long-term effects of SAS NP (NM-203) on spleen and liver as target organs following short-term exposure. Adult male and female Sprague-Dawley rats were treated by IV injection in the tail vein with a single (1-day) dose (SD) and repeated (5-day) doses (RD) of 20 mg/kg bw per day of SAS dispersed in sterile saline solution as vehicle. Histopathological examinations of target organs were performed after 90 days. Tissue biodistribution and full characterization of NM-203, primary particle size 13–45 nm, was performed within the framework of the Nanogenotox project. No mortality or general toxicity occurred; histopathological analysis showed splenomegaly in the RD group accompanied by inflammatory granulomas in both sexes. Granulomas were also present in liver parenchyma in the RD (both sexes) and SD groups (male only). The histopathological results indicated that SAS NP have the potential to persist and induce sex-specific chronic inflammatory lesions in spleen and liver upon short-term treatment. Overall, the data showed that the widespread use of silica in drugs might elicit chronic reactions in spleen and liver prompting to the need of further investigations on the safety of SAS NP.

Sign in / Sign up

Export Citation Format

Share Document