Pigment Levels Research Articles

The use of photosynthetic pigments and SPAD can help in the selection of bean genotypes under fertilization organic and mineral

The common bean is cultivated in all regions of the country, representing a product of great economic and social importance. In order to ensure food security in the world, it is necessary to create alternatives to reduce the dependence on fertilizers and seeds, and in this context, organic agriculture is a sustainable alternative to ensure it. Therefore, it becomes necessary to adapt rapid methods to monitor plant nutrition in real-time. The reflectance index determined by SPAD and pigment determination can be a sustainable alternative to identify genotypes in different fertilizations (organic × mineral fertilizer). The research hypothesis is to monitor nutritional management through pigment levels and reflectance index in common bean cultivars and their adaptation into different types of fertilization (organic × mineral fertilizer). Therefore, the objective of the research was to evaluate the common bean genotypes of the type carioca, in different fertilizations (organic × mineral fertilizer), and their effects on photosynthetic pigments, and the relationship between SPAD reflectance index and productivity. The experimental design used was a 2 × 7 factorial in randomized blocks with four replications: The first factor was the fertilization (organic × mineral fertilizer)and the second were the 7 genotypes (UFU-1; UFU-2; UFU-3; UFU-4; UFU-5; UFU-6 UFU-7), with UFU-1 being a hybrid obtained between genotypes UFU-4 and UFU-7; UFU-2 and UFU-3 were commercial genotypes; and UFU-4, UFU-5, UFU-6 and UFU-7 were genotypes from the UFU germplasm bank, located in the city of Monte Carmelo, Brazil. Evaluations were carried out for the agronomic characteristics of the plants, which were: height, number of branches, length and volume of roots, dry matter, leaf area index, number of flowers, number of pods, number of seeds per pod, 100 seed weight, and productivity of the genotypes. The results were compared with chlorophyll content and SPAD reflectance index, and the genotypes showed distinct behavior for each fertilization (organic × mineral fertilizer). The genotypes recommended for the organic fertilizer were UFU-2, UFU-6, and UFU-7, which showed higher productivity. For themineral fertilizer, the best-adapted genotype was UFU-4, with a higher productive yield. In conclusion, we can affirm that the highest chlorophyll and SPAD indices can help select common bean genotypes with higher productivity and adaptation within the organic fertilizer being this the main focus of this research. However, the other variables carried out during this research also demonstrated to have significant effects, so they could be analyzed individually and could offer valuable information in the selection of the best-adapted genotypes.

Stable Colloidal Iron Oxide Nanoparticles: A New Green Nanofertilizer and Therapeutic Nutrient for Eggplant Immune Response Against Fusarium Wilt Disease

Cultivating crops often presents numerous challenges, including resource loss such as water, fertilizers, and pesticides, as well as the spread and escalation of infections. Nanotechnology offers promising solutions to enhance plant immunity and resolve agricultural issues. In this study, in order to prevent Fusarium-wilt disease in eggplants, we concentrated on the simple manufacture of colloidal ferric oxide nanoparticles (Fe2O3 NPs) as a promising nanofertilizers. To evaluate the effectiveness of systemic resistance (SR) development, we evaluated markers of metabolic resistance, photosynthetic pigments, plant protection, and disease index (DI). Positively, Fe2O3 NPs exhibit significant antifungal activity against Fusarium oxysporum. However, when applied at a concentration of 20 µg/mL, Fe2O3 NPs proved to be the most effective treatment, reducing the percent disease index (PDI) from 82.5% in infected control plants to 22.5%. Similar results were observed with a concentration of 10 µg/mL Fe2O3 NPs. In both healthy and diseaseed plants, Fe2O3 NP treatments also showed beneficial effects on the activity of antioxidant enzymes, osmolytes, and photosynthetic pigments. Notably, compared to untreated Fusarium-infected plants, the application of Fe2O3 NPs at a concentration of 20 µg/mL significantly increased the levels of osmolyte, comprising soluble sugar, proline, and soluble protein, by 32.88%, 47.09%, and 31.34%, respectively. Furthermore, in both healthy and diseased eggplants, Fe2O3 NPs at a concentration of 20 µg/mL increased the levels of photosynthetic pigments, osmolytes, peroxidase, polyphenol oxidase, catalase, and superoxide dismutase enzymes. Overall, our research findings indicates that Fe2O3 NPs can successfully decreased the harmful effects that F. oxysporum causes to infected eggplants. With their promising therapeutic potential, these nanoparticles provide a secure and effective substitute for chemical fungicides in the management of Fusarium wilt disease.

Identification and Verification of the Blue Pigment in the Edible Jellyfish (Rhopilema esculentum)

Rhopilema esculentum is widely cultured in Chinese coastal regions and has thousand years of consumption history in China. Despite R. esculentum owns multiple colors (mainly ochre and blue) in aquaculture ponds, little is known about the pigments and color formation. This study identified and verified the blue pigment of R. esculentum. Results showed that the blue pigment of R. esculentum has 262 amino acids with 54.96% identity to the blue pigment protein precursor of Rhizostoma pulmo. The blue pigment of R. esculentum has Kringle and Frizzled domains, which is in accordance with rhizostomins characteristics. Compared to ochre R. esculentum, the expression level of blue pigment increased 3.49-fold in blue R. esculentum. In addition, overexpression of the blue pigment in Rhodosporidium toruloides made transformant cells blue under blue light excitation. Our findings provide knowledge for the blue color formation of R. esculentum and will benefit the color selection of R. esculentum with excellent traits.

The physiological responses of celery (Apium graveolens L.) and its ability to accumulate selenium when inoculated with Funneliformis mosseae

Celery (Apium graveolens L.) has a strong capacity to enrich selenium (Se) and is a good system for research on Se enrichment in vegetables. Arbuscular mycorrhizal fungi (AMF) are commonly used plant symbionts that affect plant growth and their effectiveness is plant species specific. However, there is little research on the effects of AMF inoculation on the accumulation and translocation of Se in celery. The treatments in this study included inoculation with AMF (+AMF) and the application of different types and concentrations of exogenous Se. We evaluated the growth, root mycorrhizal colonization, photosynthetic pigment content, ascorbate-glutathione cycle (ASA-GSH cycle), the accumulation and translocation of Se and the combination of AMF + Se compared with an untreated control. The application of low concentrations of Se (≤10 mg kg−1) stimulated celery growth, while high concentrations (>20 mg kg−1) had the opposite effect. The inhibition of celery growth was more severe with Se6+ than Se4+ when applied at the same concentration. The accumulation of Se improved in all the organs of celery as the supply increased. AMF had a significant positive effect on the accumulation and translocation of Se. In addition, +AMF significantly increased the shoot height and root fresh weight of celery and reduced the inhibitory effect of Se on growth. However, +AMF had slight effects on the levels of photosynthetic pigments and the ASA-GSH cycle. +AMF combined with 10 mg kg−1 sodium selenite (Se4+) is an effective way to produce Se-rich celery.

Novel Bioformulations with Trichoderma lixii to Improve the Growth Dynamics and Biocontrol of the Cowpea Damping-Off Disease

Because agricultural wastes are abundant in biologically active substances, they can be used as a substitute source to produce highly valuable products while lowering pollution levels in the environment. Therefore, we aimed at determining the best agricultural wastes to increase the biomass production rate and the effectiveness of the biocontrol strain Trichoderma lixii SARS 111 in a solid-state fermentation system. The potential for its use in enhancing growth dynamics and controlling the Fusarium oxysporum NCAIM-F-00779-caused damping-off disease of cowpea plants grown in greenhouse conditions was also studied. Using a one-factor-at-a-time experiment, five cheap agricultural waste substrates (faba bean, cowpea, sweet potato, pumpkin, and cassava) were studied using the Plackett–Burman design (PBD) and the central composite design (CCD) to optimize the nutritional and growth conditions to maximize the production of Trichoderma conidia. The findings demonstrated that increasing Candida production quantitatively required the use of 3 g of sweet potato, 3 g of cassava, pH 6, 25 °C, and pre-treatment with dH2O. The shelf life and viability of T. lixii strain were measured as log10 CFU g−1 per substrate at room temperature (RT, 25 °C) at the beginning of month 0 and subsequently at 2-month intervals for 12 months. Data showed that the fungal counts increased with the use of 4 g of sweet potato + 2 g of cassava up to 7 months and then sharply decreased, lasting up to 12 months. Additionally, this bioformulation was applied to cowpea plants in a greenhouse experiment, where a significantly higher level of plant growth traits, photosynthetic pigments, antioxidant enzymes, and chemical content in the leaves, as well as lower incidence of the damping-off disease, were noted. Accordingly, it is possible to suggest 4 g of sweet potato and 2 g of cassava as a suitable bioformulation for the industrial-scale production of the T. lixii strain, which may be a potential biocontrol agent for preventing the cowpea damping-off disease caused by F. oxysporum and improving the growth dynamics.

Organogermanium, Ge-132, promotes the clearance of senescent red blood cells via macrophage-mediated phagocyte activation

Red blood cells (RBCs) are renewed in a cyclic manner. Aging RBCs are captured and degraded by phagocytic cells, and heme metabolic pigments are subsequently excreted in feces. We evaluated the effect of an organogermanium compound on RBC metabolism and found that the phagocytosis of RAW264.7 macrophage-like cells was increased by treatment with 3-(trihydroxygermyl)propanoic acid (THGP). Additionally, consumption of Ge-132 (a dehydrate polymer of THGP) changed the fecal color to bright yellow and increased the erythrocyte metabolic pigment levels and antioxidant activity in feces. These data suggest that Ge-132 may activate macrophages in the body and promote the degradation of aged RBCs. Furthermore, Ge-132 intake promoted not only increases in RBC degradation but also the induction of erythroblast differentiation in bone marrow cells. The normal hematocrit levels were maintained due to the maintenance of homeostasis, even though Ge-132 ingestion increased erythrocyte degradation. Therefore, Ge-132 enhances the degradation of senescent RBCs by macrophages. In turn, RBC production is increased to compensate for the amount of degradation, and RBC metabolism is increased.

Metal accumulation and genetic adaptation of Oryza sativa to Cadmiun and Chromium heavy metal stress: A hydroponic and RAPD analyses

This research was performed to assess the influence of Cd and Cr metals on growth, pigments, antioxidant, and genomic stability of Oryza sativa indica and Oryza sativa japonica were investigated under hydroponic conditions. The results revealed that significant metal influence on test crop growth, pigment content, metal stress balancing antioxidant activity in a dose dependent manner. Since, while at elevated (500 ppm) concentration of Cd as well as Cr metals the pigment (total chlorophyll, chlorophyll a, b and carotenoids) level was reduced than control; however antioxidant activity (total antioxidant, H2O2, and NO) was considerably improved as protective mechanisms to combat the metal toxicity and support the plant growth. Furthermore, the test crops under typical hydroponic medium (loaded with Cd and Cr as 200, 300, 400, and 500 ppm) growth conditions, effectively absorb the metals from medium and accumulated in the root and least quantity was translocated to the shoot of this test crops. Furthermore, typical RAPD analysis with 10 universal primers demonstrated that the genomic DNA of the test crops was adaptable to develop metal resistance and ensure crop growth under increased concentrations (500 ppm) of tested heavy metals. These findings suggest that these edible crops have the ability to accumulate Cd along with Cr metals, and additionally that their genetic systems have the ability to adapt to metal-stressed environments.

Eumelanin Detection in Melanized Focal Changes but Not in Red Focal Changes on Atlantic Salmon (Salmo salar) Fillets

Superficial discolored spots on Atlantic salmon (Salmo salar) fillets are a serious quality problem for commercial seafood farming. Previous reports have proposed that the black spots (called melanized focal changes (MFCs)) may be melanin, but no convincing evidence has been reported. In this study, we performed chemical characterization of MFCs and of red pigment (called red focal changes (RFCs)) from salmon fillets using alkaline hydrogen peroxide oxidation and hydroiodic acid hydrolysis. This revealed that the MFCs contain 3,4-dihydroxyphenylalanine (DOPA)-derived eumelanin, whereas the RFCs contain only trace amounts of eumelanin. Therefore, it is probable that the black color of the MFCs can be explained by the presence of eumelanin from accumulated melanomacrophages. For the red pigment, we could not find a significant signature of either eumelanin or pheomelanin; the red color is probably predominantly hemorrhagic in nature. However, we found that the level of pigmentation in RFCs increased together with some melanogenic metabolites. Comparison with a “mimicking experiment”, in which a mixture of a salmon homogenate + DOPA was oxidized with tyrosinase, suggested that the RFCs include conjugations of DOPAquinone and/or DOPAchrome with salmon muscle tissue proteins. In short, the results suggest that melanogenic metabolites in MFCs and RFCs derive from different chemical pathways, which would agree with the two different colorations deriving from distinct cellular origins, namely melanomacrophages and red blood cells, respectively.

The Pharmacological Effect of Hemin in Inflammatory-Related Diseases: Protocol for a Systematic Review.

Hemin is a commonly used drug in the treatment of acute attacks of porphyria, due to its capability of restoring normal levels of hemoproteins and respiratory pigments. In addition, this drug has demonstrated the capacity to induce the heme oxygenase (HO) enzyme. At the moment, there are 3 known HO isoenzymes in mammals: HO-1, HO-2, and HO-3. The first of these shows cytoprotective, antioxidant, and anti-inflammatory effects. Currently, medicines used in inflammatory disorders have increased toxicity, especially over longer time frames, which highlights the need to investigate new, safer options. Indeed, the current nonclinical evidence demonstrates the potential that hemin has a significant anti-inflammatory effect in several animal models of inflammation-related diseases, such as experimental colitis, without significant side effects. However, the underlying mechanism(s) are still not fully understood. In addition, past nonclinical studies have applied different therapeutic regimens, making it relatively difficult to understand which is optimal. According to the literature, there is a lack of review articles discussing this topic, highlighting the need for a summary and analysis of the available preclinical evidence to elucidate the abovementioned issues. Therefore, a qualitative synthesis of the current evidence is essential for the research and medical communities. This systematic review aims to summarize and analyze currently available nonclinical data to ascertain the potential anti-inflammatory effect of hemin in animal models. Throughout the development of this protocol, we followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol. The comprehensive search strategy will be carried out in MEDLINE (PubMed), Web of Science, and Scopus without any filters associated with publication date. Only in vivo, nonclinical studies that evaluated the potential anti-inflammatory effect of hemin will be included. The evaluated outcomes will be the observed clinical signs, inflammatory and other biochemical markers, and macroscopic and microscopic evaluations. To analyze the potential risk of bias, we will use the risk of bias tool developed by the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE). Currently, it is not possible to disclose any results since the project is still in initial steps. More specifically, we are currently engaged in the identification of eligible articles through the application of the inclusion and exclusion criteria. The work was initiated in April 2023, and it is expected to be finished at the end of 2023. Concerning the major gap in the literature regarding the underlying mechanism(s) and treatment-related properties, this systematic review will be essential to clearly summarize and critically analyze the nonclinical data available, promoting a clearer vision of the potential anti-inflammatory effect of hemin. PROSPERO CRD42023406160; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=406160. PRR1-10.2196/48368.

Cross-ancestry analyses identify new genetic loci associated with 25-hydroxyvitamin D.

Vitamin D status-a complex trait influenced by environmental and genetic factors-is tightly associated with skin colour and ancestry. Yet very few studies have investigated the genetic underpinnings of vitamin D levels across diverse ancestries, and the ones that have, relied on small sample sizes, resulting in inconclusive results. Here, we conduct genome-wide association studies (GWAS) of 25 hydroxyvitamin D (25OHD)-the main circulating form of vitamin D-in 442,435 individuals from four broad genetically-determined ancestry groups represented in the UK Biobank: European (N = 421,867), South Asian (N = 9,983), African (N = 8,306) and East Asian (N = 2,279). We identify a new genetic determinant of 25OHD (rs146759773) in individuals of African ancestry, which was not detected in previous analysis of much larger European cohorts due to low minor allele frequency. We show genome-wide significant evidence of dominance effects in 25OHD that protect against vitamin D deficiency. Given that key events in the synthesis of 25OHD occur in the skin and are affected by pigmentation levels, we conduct GWAS of 25OHD stratified by skin colour and identify new associations. Lastly, we test the interaction between skin colour and variants associated with variance in 25OHD levels and identify two loci (rs10832254 and rs1352846) whose association with 25OHD differs in individuals of distinct complexions. Collectively, our results provide new insights into the complex relationship between 25OHD and skin colour and highlight the importance of diversity in genomic studies. Despite the much larger rates of vitamin D deficiency that we and others report for ancestry groups with dark skin (e.g., South Asian), our study highlights the importance of considering ancestral background and/or skin colour when assessing the implications of low vitamin D.

The Adaptive Role of Carotenoids and Anthocyanins in Solanum lycopersicum Pigment Mutants under High Irradiance.

The effects of high-intensity light on the pigment content, photosynthetic rate, and fluorescence parameters of photosystem II in high-pigment tomato mutants (hp 3005) and low-pigment mutants (lp 3617) were investigated. This study also evaluated the dry weight percentage of low molecular weight antioxidant capacity, expression patterns of some photoreceptor-regulated genes, and structural aspects of leaf mesophyll cells. The 3005 mutant displayed increased levels of photosynthetic pigments and anthocyanins, whereas the 3617 mutant demonstrated a heightened content of ultraviolet-absorbing pigments. The photosynthetic rate, photosystem II activity, antioxidant capacity, and carotenoid content were most pronounced in the high-pigment mutant after 72 h exposure to intense light. This mutant also exhibited an increase in leaf thickness and water content when exposed to high-intensity light, suggesting superior physiological adaptability and reduced photoinhibition. Our findings indicate that the enhanced adaptability of the high-pigment mutant might be attributed to increased flavonoid and carotenoid contents, leading to augmented expression of key genes associated with pigment synthesis and light regulation.

Epigenetics insights from perceived facial aging

Facial aging is the most visible manifestation of aging. People desire to look younger than others of the same chronological age. Hence, perceived age is often used as a visible marker of aging, while biological age, often estimated by methylation markers, is used as an objective measure of age. Multiple epigenetics-based clocks have been developed for accurate estimation of general biological age and the age of specific organs, including the skin. However, it is not clear whether the epigenetic biomarkers (CpGs) used in these clocks are drivers of aging processes or consequences of aging. In this proof-of-concept study, we integrate data from GWAS on perceived facial aging and EWAS on CpGs measured in blood. By running EW Mendelian randomization, we identify hundreds of putative CpGs that are potentially causal to perceived facial aging with similar numbers of damaging markers that causally drive or accelerate facial aging and protective methylation markers that causally slow down or protect from aging. We further demonstrate that while candidate causal CpGs have little overlap with known epigenetics-based clocks, they affect genes or proteins with known functions in skin aging, such as skin pigmentation, elastin, and collagen levels. Overall, our results suggest that blood methylation markers reflect facial aging processes, and thus can be used to quantify skin aging and develop anti-aging solutions that target the root causes of aging.

Correlations between inflammatory cytokine levels and degree of pigmentation in acral melanomas.

Cutaneous melanoma, a highly aggressive skin tumor, is characterized by complex signaling pathways in terms of its pathogenesis and progression. Although the degree of pigmentation in melanoma determines its progression, metastasis, and prognosis, its association with inflammatory cytokines remains unclear. Thus, we evaluated the associations between melanoma pigmentation and plasma levels of inflammatory cytokines; furthermore, we investigated the potential variations in this relationship across the primary anatomic sites of melanoma. We enrolled patients with cutaneous melanoma who visited Chonnam National University Hwasun Hospital between January 2021 and December 2021. The anatomical sites of melanoma were categorized as acral and non-acral sites. The degree of pigmentation was quantified using computer software. In total, nine inflammatory cytokines were analyzed, including interleukin (IL)-2, IL-4, IL-5, IL-10, IL-12, IL-13, granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon-γ (IFN-γ), and tumor necrosis factor-α (TNF-α). This study included 80 melanoma patients. Of these, 53 had acral melanoma and 27 had non-acral melanoma. Overall, plasma concentrations of IL-2, IL-4, IL-5, GM-CSF, and IFN-γ demonstrated significant correlations with diminished pigmentation. Furthermore, in the acral melanoma patients group, plasma concentrations of IL-2, IL-4, IL-5, GM-CSF, IFN-γ, and TNF-α revealed significant correlations with diminished pigmentation. Our results reveal significant associations between melanoma pigmentation and various cytokine levels, particularly in acral melanoma patients; these associations can be influenced by factors related to acral melanoma, such as physical stress or trauma. These correlations may also provide directions for the treatment of acral melanoma.

Shining a light on duckweed: exploring the effects of artificial light at night (ALAN) on growth and pigmentation.

Artificial light at night (ALAN) is a novel environmental stressor of global concern. Various sources of artificial light are now common in urbanized areas and have diverse negative effects on many species of animals and plants. However, ALAN has also been shown to have no effect or a positive effect on some organisms. This study investigates the impact of ALAN on the growth and leaf pigmentation of a common floating freshwater plant species. We exposed wild-derived dotted duckweed (Landoltia punctata) to either darkness during the night (Control group) or to artificial light at night (ALAN group) for 49 days. We set up two large boxes of eighty samples each with 2-3 leaves of duckweed in each sample at the start of the experiment. The ALAN box had an opaque lid with a small lamp that was turned on at night. The Control box was also covered at night with an opaque lid but without a lamp. During the day, plants in both boxes were exposed to natural light. We counted the number of leaves in each sample weekly. We took photos of the samples on day 28 to measure the total leaf surface area per sample. On day 49, we took photos of the underside of the leaves for analyses of the relative levels of dark pigmentation across all samples. We found that ALAN-exposed plant samples had, on average, more leaves than control plants after a few weeks of exposure. They also had a more variable number of leaves per sample. The total leaf area per sample on day 28 was larger in the ALAN samples. The underside of the leaves on day 49 was, on average, darker in the ALAN plants than in the control plants. There is a significant growth-enhancing effect from exposure to artificial light at night on Landolita punctata. However, higher variability induced by ALAN exposure indicates that ALAN is also a stressful condition for these plants. This is in line with our finding of the presence of larger amounts of dark pigments in the leaves of ALAN-exposed plants. Dark pigmentation in duckweed species could be a defence mechanism protecting tissues from stress-induced oxidative damage. Overall, both positive and negative effects of ALAN can be observed simultaneously in different traits of the same organism. Increased individual variation can facilitate population-level adaptation to stressful conditions. As such, this work contributes to our knowledge of the effects of light pollution in urban environments on common plants.

Comprehensive physiological, transcriptomic, and metabolomic analysis of the key metabolic pathways in millet seedling adaptation to drought stress.

Drought is one of the leading environmental constraints that affect the growth and development of plants and, ultimately, their yield and quality. Foxtail millet (Setaria italica) is a natural stress-resistant plant and an ideal model for studying plant drought resistance. In this study, two varieties of foxtail millet with different levels of drought resistance were used as the experimental material. The soil weighing method was used to simulate drought stress, and the differences in growth, photosynthetic physiology, metabolite metabolism, and gene transcriptional expression under drought stress were compared and analyzed. We aimed to determine the physiological and key metabolic regulation pathways of the drought-tolerant millet in resistance to drought stress. The results showed that drought-tolerant millet exhibited relatively stable growth and photosynthetic parameters under drought stress while maintaining a relatively stable level of photosynthetic pigments. The metabolomic, transcriptomic, and gene co-expression network analysis confirmed that the key to adaptation to drought by millet was to enhance lignin metabolism, promote the metabolism of fatty acids to be transformed into cutin and wax, and improve ascorbic acid circulation. These findings provided new insights into the metabolic regulatory network of millet adaptation to drought stress.

Photoprotective responses of three intertidal Antarctic macroalgae to short-term temperature stress

The Antarctic Peninsula is experiencing one of the highest warming rates globally. In polar regions, macroalgae thrive under extreme environmental conditions, which could worsen because of future climate change scenarios, including increased ultraviolet exposure, extremely low light availability, and fluctuating temperatures, particularly in the intertidal zones. To investigate the potential role of photoprotective and antioxidant mechanisms in response to future increases in sea surface temperatures caused by climate change, we conducted laboratory experiments using three intertidal macroalgae model species: Adenocystis utricularis (Ochrophyta, Phaeophyceae), Pyropia endiviifolia (Rhodophyta, Bangiophyceae), and Monostroma hariotii (Chlorophyta, Ulvophyceae). These algae were collected in Punta Artigas (King George Island, Antarctica) and acclimated at 2°C for 48 h. They were then assessed in laboratory experiments for up to 5 days under two treatments: (1) control conditions at 2°C and (2) elevated tem.perature conditions at 8°C, representing the most negative increment in SSTs estimated by the end of the 21st century. Carbon, nitrogen, pigments (chlorophylls and carotenoids), mycosporine-like amino acids (MAAs), and phenolic compounds were quantified after 3 and 5 days of exposure. For M. hariotii, elevated temperatures led to an increase in the C/N ratio, total antioxidant capacity, and levels of nitrogen, total carotenoids, chlorophyll-a, pigments (chlorophyll-b and violaxanthin), and phenolic compounds. For A. utricularis, elevated temperatures led to elevated C/N ratio and levels of chlorophyll-a and carotenoids (fucoxanthin and β-carotene). For P. endiviifolia, elevated temperatures resulted in elevated levels of carotenoids (lutein and β-carotene), phenolic compounds, and MAAs (porphyra-334, shinorine, and palythine). Thus, our study suggests that increasing water temperatures due to global warming can enhance the photoprotective abilities of three Antarctic intertidal macroalgae (M. hariotii, A. utricularis, and P. endiviifolia), with each species showing specific responses.

Physio-biochemical responses of registered bread wheat (Triticum aestivum L.) genotypes to drought stress: Variations in antioxidant parameters and photosynthetic pigment amounts

In this study, physio-biochemical parameters of 7 registered bread wheat (Triticum aestivum L.) genotypes (Gerek 79, Sultan 95, Haymana 79, Grk/Cty, T98-9, Pastor, PM ME1) were investigated under drought stress conditions. Polyphenol oxidase (PPO), peroxidase (POD), ascorbate peroxidase (APX), catalase (CAT), photosynthetic pigment, total protein, hydrogen peroxide, lipid peroxidation (malonyldialdehyde-MDA) and proline levels were determined in this wheat genotypes exposed to different drought duration (3rd, 6th and 10th day). As a result of this study, among 7 different wheat genotypes, Gerek 79 and Haymana 79 genotypes were the most physiologically sensitive to drought. In comparison, Pastor and Sultan 95 genotypes were the most drought-tolerant varieties. In addition, in parallel with the prolongation of the drought period in wheat varieties in general, it was determined that the content of photosynthetic pigments decreased significantly due to oxidative damage, while proline and MDA content increased

Effect of Different Rootstocks on the Salt Stress Tolerance and Fruit Quality of Grafted Eggplants (Solanum melongena L.).

Vegetable grafting is considered a rapid, non-chemical alternative method to relatively slow and expensive breeding to overcome the adverse effect of salinity. Therefore, a soilless experiment was performed to determine the salinity tolerance of eggplant (Solanum melongena) cv. Madonna grafted onto two different rootstocks, Solanum grandifolium × Solanum melongena (SH) and Solanum torvum (ST), as well as self-grafted (SG) and self-rooted (SR) as controls. All groups of plants were treated with 0 mM NaCl or 80 mM NaCl. A significant decrease in the relative leaf chlorophyll content (SPAD value) and chlorophyll concentrations were found in response to NaCl. However, the grafted plants had a higher photosynthetic pigment level than the non-grafted plants grown under saline conditions. Grafting eggplants onto SH significantly enhanced the total fruit yield as compared to the self-rooted plants exposed to salinity by increasing the average fruit weight. Moreover, salt stress significantly increased the whitening index and oxidation potential of fruits. The plants grafted onto SH or ST accumulated more Na+ in their roots than in their fruit or leaves, thus the Na+ partitioning between the above-ground and root parts most probably determines the increased salinity tolerance of the grafted ST and SH plants. To conclude, both the SH and ST rootstocks protected the scions against salinity; the scion showed both increased photosynthetic pigment concentration and chlorophyll fluorescence parameters as well as a lower Na+ concentration under stress that resulted in a higher fruit yield and quality.

Race, pigmentation, and the human skin barrier-considerations for dermal absorption studies.

A functional human skin barrier is critical in limiting harmful exposure to environmental agents and regulating the absorption of intentionally applied topical drug and cosmetic products. Inherent differences in the skin barrier between consumers due to extrinsic and intrinsic factors are an important consideration in the safety assessment of dermatological products. Race is a concept often used to describe a group of people who share distinct physical characteristics. The observed predisposition of specific racial groups to certain skin pathologies highlights the potential differences in skin physiology between these groups. In the context of the human skin barrier, however, the current data correlating function to race often conflict, likely as a consequence of the range of experimental approaches and controls used in the existing works. To date, a variety of methods have been developed for evaluating compound permeation through the human skin, both in vivo and in vitro. Additionally, great strides have been made in the development of reconstructed human pigmented skin models, with the flexibility to incorporate melanocytes from donors of different race and pigmentation levels. Together, the advances in the production of reconstructed human skin models and the increased adoption of in vitro methodologies show potential to aid in the standardization of dermal absorption studies for discerning racial- and skin pigmentation-dependent differences in the human skin barrier. This review analyzes the existing data on skin permeation, focusing on its interaction with race and skin pigmentation, and highlights the tools and research opportunities to better represent the diversity of the human populations in dermal absorption assessments.

CHIASM-Net: Artificial Intelligence-Based Direct Identification of Chiasmal Abnormalities in Albinism.

Albinism is a congenital disorder affecting pigmentation levels, structure, and function of the visual system. The identification of anatomical changes typical for people with albinism (PWA), such as optic chiasm malformations, could become an important component of diagnostics. Here, we tested an application of convolutional neural networks (CNNs) for this purpose. We established and evaluated a CNN, referred to as CHIASM-Net, for the detection of chiasmal malformations from anatomic magnetic resonance (MR) images of the brain. CHIASM-Net, composed of encoding and classification modules, was developed using MR images of controls (n = 1708) and PWA (n = 32). Evaluation involved 8-fold cross validation involving accuracy, precision, recall, and F1-score metrics and was performed on a subset of controls and PWA samples excluded from the training. In addition to quantitative metrics, we used Explainable AI (XAI) methods that granted insights into factors driving the predictions of CHIASM-Net. The results for the scenario indicated an accuracy of 85 ± 14%, precision of 90 ± 14% and recall of 81 ± 18%. XAI methods revealed that the predictions of CHIASM-Net are driven by optic-chiasm white matter and by the optic tracts. CHIASM-Net was demonstrated to use relevant regions of the optic chiasm for albinism detection from magnetic resonance imaging (MRI) brain anatomies. This indicates the strong potential of CNN-based approaches for visual pathway analysis and ultimately diagnostics.