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1.
Proc Natl Acad Sci U S A ; 121(11): e2303366121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38437536

RESUMO

Phytoplankton and sea ice algae are traditionally considered to be the main primary producers in the Arctic Ocean. In this Perspective, we explore the importance of benthic primary producers (BPPs) encompassing microalgae, macroalgae, and seagrasses, which represent a poorly quantified source of Arctic marine primary production. Despite scarce observations, models predict that BPPs are widespread, colonizing ~3 million km2 of the extensive Arctic coastal and shelf seas. Using a synthesis of published data and a novel model, we estimate that BPPs currently contribute ~77 Tg C y-1 of primary production to the Arctic, equivalent to ~20 to 35% of annual phytoplankton production. Macroalgae contribute ~43 Tg C y-1, seagrasses contribute ~23 Tg C y-1, and microalgae-dominated shelf habitats contribute ~11 to 16 Tg C y-1. Since 2003, the Arctic seafloor area exposed to sunlight has increased by ~47,000 km2 y-1, expanding the realm of BPPs in a warming Arctic. Increased macrophyte abundance and productivity is expected along Arctic coastlines with continued ocean warming and sea ice loss. However, microalgal benthic primary production has increased in only a few shelf regions despite substantial sea ice loss over the past 20 y, as higher solar irradiance in the ice-free ocean is counterbalanced by reduced water transparency. This suggests complex impacts of climate change on Arctic light availability and marine primary production. Despite significant knowledge gaps on Arctic BPPs, their widespread presence and obvious contribution to coastal and shelf ecosystem production call for further investigation and for their inclusion in Arctic ecosystem models and carbon budgets.


Assuntos
Microalgas , Alga Marinha , Ecossistema , Orçamentos , Carbono , Mudança Climática , Camada de Gelo , Fitoplâncton
2.
Planta ; 260(6): 124, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39443340

RESUMO

MAIN CONCLUSION: The chromosome-level genome assembly of Citrullus colocynthis reveals its genetic potential for enhancing drought tolerance, paving the way for innovative crop improvement strategies. This study presents the first comprehensive genome assembly and annotation of Citrullus colocynthis, a drought-tolerant wild close relative of cultivated watermelon, highlighting its potential for enhancing agricultural resilience to climate change. The study achieved a chromosome-level assembly using advanced sequencing technologies, including PacBio HiFi and Hi-C, revealing a genome size of approximately 366 Mb with low heterozygosity and substantial repetitive content. Our analysis identified 23,327 gene models, that could encode stress response mechanisms for species' adaptation to arid environments. Comparative genomics with closely related species illuminated the evolutionary dynamics within the Cucurbitaceae family. In addition, resequencing of 27 accessions from the United Arab Emirates (UAE) identified genetic diversity, suggesting a foundation for future breeding programs. This genomic resource opens new avenues for the de novo domestication of C. colocynthis, offering a blueprint for developing crops with enhanced drought tolerance, disease resistance, and nutritional profiles, crucial for sustaining future food security in the face of escalating climate challenges.


Assuntos
Citrullus colocynthis , Produtos Agrícolas , Secas , Genoma de Planta , Genoma de Planta/genética , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Citrullus colocynthis/genética , Citrullus colocynthis/fisiologia , Anotação de Sequência Molecular , Cromossomos de Plantas/genética , Citrullus/genética , Citrullus/crescimento & desenvolvimento , Citrullus/fisiologia , Emirados Árabes Unidos , Genômica/métodos , Variação Genética , Filogenia
3.
Opt Lett ; 49(2): 326-329, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38194560

RESUMO

We present and experimentally demonstrate a new, to the best of our knowledge, technique to quantitatively measure coherence-polarization (BCP) matrix with correlations of only two Stokes fluctuations. The BCP matrix is a square matrix with four elements that involves two-point correlations among orthogonal polarization components. A theoretical framework of the technique is developed, and its viability is demonstrated by a proof of principle experiment. Experimental tests and measurement of the elements of the BCP matrix of statistically stationary beams are demonstrated.

4.
J Opt Soc Am A Opt Image Sci Vis ; 41(1): 95-103, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38175134

RESUMO

Topological defects in vector fields constitute polarization singularities that have numerous applications in classical and quantum optics. These beams are inhomogeneously polarized and are shown to self-heal under symmetric amplitude perturbations. Polarization singular beams are characterized using a singularity index that can be detected using Stokes polarimetry or other interferometric and diffraction approaches. However, the information about the singularity index is lost when these beams travel through random scattering media; this results in a spatially fluctuating polarization pattern known as polarization speckle. This paper proposes and experimentally demonstrates a new method to detect the topological index of these randomly scattered V-point singularities using higher-order Stokes correlations in a lensless condition. A detailed theoretical basis is developed, and the performance of the technique is demonstrated by retrieving the signature of polarization singularities with Poincaré-Hopf index |η|=1 and |η|=2. We also demonstrate that by studying the intensity-intensity correlations of the polarization speckle, it is possible to differentiate between different vector beams having the same magnitude as the Poincaré-Hopf index.

5.
Toxicol Mech Methods ; 34(1): 57-71, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37680063

RESUMO

BACKGROUND: Iron is one of the essential metals that functions as a cofactor in various biological cascades in the brain. However, excessive iron accumulation in the brain may lead to neurodegeneration and may show toxic effects. Quercetin, a pigment flavonoid compound, has been proven to be a potent antioxidant and anti-inflammatory that can inhibit lipid peroxidation during metal-induced neurotoxicity. Although iron-induced neuroinflammation and neurodegeneration have been reported in many studies, but the proof for its exact mechanisms needs to be explored. PURPOSE: The key target of the study was to explore the neuroprotective effect of quercetin after oral exposure of iron in rats and explore its underlying molecular mechanisms. RESULTS: The outcomes of the study have shown that oral exposure to ferrous sulfate may modulate behavioral paradigms such as locomotor activity, neuromuscular coordination, and increased anxiety level. The pro-inflammatory cytokines (TNF-α, IL-1ß and IL-6), apoptotic protein (caspase 3), beta-amyloid and phosphorylated tau were found to be increased on iron exposure. Also, the expressions of ferritin heavy and light chain, BACE-1 and GFAP expressions were altered. These behavioral, structural, and biochemical alterations in the brain were significantly and dose-dependently reversed by treatment with quercetin. CONCLUSION: The current study provides a fundamental understanding of molecular signaling pathways, and structural proteins implicated in iron-induced neurotoxicity along with the ameliorative effects of quercetin.


Assuntos
Fármacos Neuroprotetores , Quercetina , Ratos , Animais , Quercetina/farmacologia , Ferro/toxicidade , Ferro/metabolismo , Antioxidantes/metabolismo , Encéfalo , Transdução de Sinais , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico
6.
NMR Biomed ; 36(5): e4884, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36453877

RESUMO

The peritumoral vasogenic edema (PVE) in brain tumors exhibits varied characteristics. Brain metastasis (BM) and meningioma barely have tumor cells in PVE, while glioblastoma (GB) show tumor cell infiltration in most subjects. The purpose of this study was to investigate the PVE of these three pathologies using radiomics features in FLAIR images, with the hypothesis that the tumor cells might influence textural variation. Ex vivo experimentation of radiomics analysis of T1-weighted images of the culture medium with and without suspended tumor cells was also attempted to infer the possible influence of increasing tumor cells on radiomics features. This retrospective study involved magnetic resonance (MR) images acquired using a 3.0-T MR machine from 83 patients with 48 GB, 21 BM, and 14 meningioma. The 93 radiomics features were extracted from each subject's PVE mask from three pathologies using T1-dynamic contrast-enhanced MR imaging. Statistically significant (< 0.05, independent samples T-test) features were considered. Features maps were also computed for qualitative investigation. The same was carried out for T1-weighted cell line images but group comparison was carried out using one-way analysis of variance. Further, a random forest (RF)-based machine learning model was designed to classify the PVE of GB and BM. Texture-based variations, especially higher nonuniformity values, were observed in the PVE of GB. No significance was observed between BM and meningioma PVE. In cell line images, the culture medium had higher nonuniformity and was considerably reduced with increasing cell densities in four features. The RF model implemented with highly significant features provided improved area under the curve results. The possible infiltrative tumor cells in the PVE of the GB are likely influencing the texture values and are higher in comparison with BM PVE and may be of value in the differentiation of solitary metastasis from GB. However, the robustness of the features needs to be investigated with a larger cohort and across different scanners in the future.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Neoplasias Meníngeas , Meningioma , Humanos , Glioblastoma/diagnóstico por imagem , Glioblastoma/patologia , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Perfusão , Edema
7.
J Recept Signal Transduct Res ; 43(1): 1-8, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36651469

RESUMO

THE PURPOSE OF THE ARTICLE: To identify novel small molecule antagonists of Urotensin II receptor with acceptable pharmacological profile. MATERIALS AND METHODS: Structure-activity-relationship (SAR) studies on 2-{N-[(2,4,5-trichlorophenoxy) acetyl]-N-methylamino}-3-pyrrolidinepropanamide series were conducted and shortlisted compounds were synthesized and evaluated in in vitro cell-based assays. Human and mouse Urotensin II receptor overexpressing CHO cells were used for calcium release and radioligand binding assays. Initial molecules in this series had solubility and inter-species variability issue in the calcium release assay. We, therefore, conducted SAR to overcome these 2 issues and molecules with accepted in vitro profile were evaluated further in mouse pressor response model to generate the in vivo proof of concept for UII receptor antagonization. RESULTS AND CONCLUSIONS: We report herewith identification of 2-{N-[(2,4,5-trichlorophenoxy)acetyl]-N-methylamino}-3-pyrrolidinepropanamides series to obtain novel small molecule antagonists of Urotensin II receptor with acceptable pharmacological profile.


Assuntos
Cálcio , Urotensinas , Camundongos , Cricetinae , Animais , Humanos , Cricetulus , Cálcio/metabolismo , Urotensinas/química , Urotensinas/metabolismo , Urotensinas/farmacologia , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Células CHO
8.
Opt Lett ; 48(13): 3391-3394, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37390138

RESUMO

The Hanbury Brown-Twiss approach, associated with the correlation of intensity fluctuations at two different points in a wave field, unveils fundamental aspects of light. Here, we propose and experimentally demonstrate an imaging and phase recovery technique through a dynamic scattering medium using the Hanbury Brown-Twiss approach. A detailed theoretical basis is presented and verified by experimental demonstrations. To validate the application of the proposed technique, the randomness of the dynamically scattered light is exploited using temporal ergodicity for evaluating the correlation of intensity fluctuations and consequently applying it in the reconstruction of the object hidden behind the dynamic diffuser.

9.
J Environ Manage ; 343: 118222, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37235991

RESUMO

Biochar, a promising carbon-rich and carbon-negative material, can control water pollution, harness the synergy of sustainable development goals, and achieve circular economy. This study examined the performance feasibility of treating fluoride-contaminated surface and groundwater using raw and modified biochar synthesized from agricultural waste rice husk as problem-fixing renewable carbon-neutral material. Physicochemical characterizations of raw/modified biochars were investigated using FESEM-EDAX, FTIR, XRD, BET, CHSN, VSM, pHpzc, Zeta potential, and particle size analysis were analyzed to identify the surface morphology, functional groups, structural, and electrokinetic behavior. In fluoride (F-) cycling, performance feasibility was tested at various governing factors, contact time (0-120 min), initial F- levels (10-50 mg L-1), biochar dose (0.1-0.5 g L-1), pH (2-9), salt strengths (0-50 mM), temperatures (301-328 K), and various co-occurring ions. Results revealed that activated magnetic biochar (AMB) possessed higher adsorption capacity than raw biochar (RB) and activated biochar (AB) at pH 7. The results indicated that maximum F- removal (98.13%) was achieved using AMB at pH 7 for 10 mg L-1. Electrostatic attraction, ion exchange, pore fillings, and surface complexation govern F- removal mechanisms. Pseudo-second-order and Freundlich were the best fit kinetic and isotherm for F- sorption, respectively. Increased biochar dose drives an increase in active sites due to F- level gradient and mass transfer between biochar-fluoride interactions, which reported maximum mass transfer for AMB than RB and AB. Fluoride adsorption using AMB could be described through chemisorption processes at room temperature (301 K), though endothermic sorption follows the physisorption process. Fluoride removal efficiency reduced, from 67.70% to 53.23%, with increased salt concentrations from 0 to 50 mM NaCl solutions, respectively, due to increased hydrodynamic diameter. Biochar was used to treat natural fluoride-contaminated surface and groundwater in real-world problem-solving measures, showed removal efficiency of 91.20% and 95.61%, respectively, for 10 mg L-1 F- contamination, and has been performed multiple times after systematic adsorption-desorption experiments. Lastly, techno-economic analysis was analyzed for biochar synthesis and F- treatment performance costs. Overall, our results revealed worth output and concluded with recommendations for future research on F- adsorption using biochar.


Assuntos
Água Subterrânea , Oryza , Poluentes Químicos da Água , Purificação da Água , Fluoretos , Oryza/química , Purificação da Água/métodos , Carvão Vegetal/química , Adsorção , Água Subterrânea/química , Cinética , Concentração de Íons de Hidrogênio
10.
Molecules ; 28(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36771169

RESUMO

Wild plants supply food and shelter to several organisms; they also act as important sources of many nutrients and pharmaceutical agents for mankind. These plants are widely used in traditional medicinal systems and folk medicines. The present study analyzed the nutritional and proximate composition of various compounds in selected wild plants available in the UAE, viz., Chenopodium murale L., Dipterygium glaucum Decne., Heliotropium digynum Asch. ex C.Chr., Heliotropium kotschyi Gürke., Salsola imbricata Forssk., Tribulus pentandrus Forssk., Zygophyllum qatarense Hadidi. The predominant amino acids detected in the plants were glycine, threonine, histidine, cysteine, proline, serine, and tyrosine; the highest quantities were observed in H. digynum and T. pentandrus. The major fatty acids present were long-chain saturated fatty acids; however, lauric acid was only present in S. imbricata. The presence of essential fatty acids such as oleic acid, α-Linoleic acid, and linolenic acid was observed in H. digynum, S. imbricata, and H. kotschyi. These plants also exhibited higher content of nutrients such as carbohydrates, proteins, fats, ash, and fiber. The predominant vitamins in the plants were vitamin B complex and vitamin C. C. murale had higher vitamin A, whereas vitamin B complex was seen in T. pentandrus and D. glaucum. The phosphorus and zinc content were high in T. pentandrus; the nitrogen, calcium, and potassium contents were high in H. digynum, and D. glaucum. Overall, these plants, especially H. digynum and T. pentandrus contain high amounts of nutritionally active compounds and important antioxidants including trace elements and vitamins. The results from the experiment provide an understanding of the nutritional composition of these desert plant species and can be better utilized as important agents for pharmacological drug discovery, food, and sustainable livestock production in the desert ecosystem.


Assuntos
Complexo Vitamínico B , Emirados Árabes Unidos , Ecossistema , Ácidos Graxos/análise , Plantas , Valor Nutritivo
11.
J Minim Access Surg ; 19(2): 257-262, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37056091

RESUMO

Aim: Remnant cystic duct stump calculi are an uncommon but important cause of 'post-cholecystectomy syndrome'. High index of suspicion is needed to diagnose this condition in a symptomatic post-cholecystectomy patient. We present our experience with the surgical management of this condition. Patients and Methods: This prospective study included 19 patients with residual gallstone disease who underwent completion cholecystectomy between August 2016 and October 2021. Investigations included abdominal ultrasound and magnetic resonance cholangiopancreatography. The demographic, clinical, surgical and early post-operative variables of these patients were prospectively maintained and analysed. Results: The study included 14 women and 5 men. The mean age was 42.1 years (range, 14-80 years). The median duration between index surgery and completion cholecystectomy was 36 months (range, 2-178 months) (interquartile range, 105 months). The follow-up duration was 2 months. The initial surgery was open cholecystectomy in 17 and laparoscopic cholecystectomy in 2 patients. All patients with residual stump stone presented with pain, while 10 out of 19 patients complained of dyspepsia. Completion cholecystectomy could be performed laparoscopically in 16 cases, whereas 3 patients underwent open surgery. The mean operative time was 80 min (range, 55-140 min), and the mean blood loss was 100 ml (range, 50-160 ml). The mean hospital stay was 3 days (range, 2-10 days). No post-operative mortality or major morbidity was recorded in any of our patients. Conclusion: Laparoscopic excision of the cystic duct stump is feasible and safe even after previous open cholecystectomy. It is increasingly becoming the treatment of choice where expertise is available.

12.
Indian J Crit Care Med ; 27(9): 625-634, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37719352

RESUMO

Background: Sepsis is associated with wide variable coagulation abnormalities. Thromboelastography (TEG) effectively measures the viscoelastic properties of the clots. This study aims to illustrate the viscoelastic properties of clot quality and mass in sepsis and septic shock patients using TEG, as an effective tool over standard coagulation tests. Materials and methods: A single-center, prospective observational study was conducted. 50 patients each meeting the criteria for sepsis and septic shock, and a healthy group of 30 patients was included in the study. Blood samples were obtained and analyzed for standard coagulation tests, platelet count, fibrinogen, and TEG study. Results: A total of 130 patients were included. Septic shock patients had a higher sequential (sepsis-related) organ failure score. Prothrombin time (PT) and activated partial thromboplastin time (aPTT) were increased significantly as compared to the sepsis and control groups. TEG markers such as alpha angle, and maximum amplitude (MA) were significantly prolonged while reaction time (R time), was significantly shortened in the sepsis group as compared to the healthy group, suggestive of a hypercoagulable state in sepsis patients. While in septic shock patients, MA and Lysis Index 30 (LY 30) were significantly prolonged and, R time was significantly shortened compared to all other groups. Even though LY30 in sepsis patients was found to be within the normal range (p < 0.001), 18% of patients had prolonged LY30 indicating a hypercoagulable state with impaired fibrinolysis. Conclusion: Thromboelastography, as a point-of-care test combined with conventional coagulation tests can provide additional, clinically relevant information on coagulopathy, and outcome, and thus help guide treatment modality in sepsis and septic shock-induced coagulopathy. How to cite this article: Mohapatra P, Kumar A, Singh RK, Gupta R, Hussain M, Singh S, et al. The Effect of Sepsis and Septic Shock on the Viscoelastic Properties of Clot Quality and Mass Using Thromboelastometry: A Prospective Observational Study. Indian J Crit Care Med 2023;27(9):625-634.

13.
Opt Lett ; 47(19): 4953-4956, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36181159

RESUMO

We propose and experimentally demonstrate an on-axis phase-shifting correlation holography technique with un-polarized light. The randomness of the un-polarized light is exploited to evaluate the higher-order polarization correlation and to consequently apply it in the reconstruction of the hologram from the randomness. A detailed theoretical analysis is developed and verified by numerical simulations and followed by experimental demonstrations. To validate the application of the proposed technique, imaging of different helical phase objects with randomness is presented. A good affinity is found between simulation and experimental results, which validates the accuracy of the proposed technique.

14.
J Biochem Mol Toxicol ; 36(12): e23210, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36056780

RESUMO

The risk of aluminium exposure to humans is very high as it may get into the human body through excessive dietary contaminants, inhalation of fine particulate matter, or through parenteral routes as a vaccine adjuvant and so forth. The increased level of aluminium in brain tissue has been shown to be associated with several neurodegenerative and neurotoxic adverse effects, including AD. However, the exact mechanism of aluminium-induced neurotoxicity is still unclear. Therefore, our study aimed to investigate the mechanism of neurotoxic and neurodegenerative effects through in vitro exposure of aluminium in rat glioma C6 cell line. The findings of our study have indicated that aluminium chloride exposure may lead to alteration in acetylcholine levels, increased oxidative imbalance and induction of molecular structural and functional markers of neuronal inflammation. This study also demonstrated that aluminium exposure may lead to the induction of caspase-3 along with apoptotic cell death and a significant increase in amyloid-beta and hyperphosphorylated tau levels in C6 cells. Thus, this study may provide a mechanistic understanding of the regulation of neuroinflammatory and neurodegenerative biomarkers due to aluminium exposure.


Assuntos
Glioma , Síndromes Neurotóxicas , Animais , Ratos , Humanos , Alumínio/toxicidade , Cloreto de Alumínio/toxicidade , Síndromes Neurotóxicas/etiologia , Síndromes Neurotóxicas/metabolismo , Neurônios/metabolismo , Glioma/metabolismo
15.
Neurol Sci ; 43(1): 285-298, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34032945

RESUMO

BACKGROUND: Numerous studies have indicated the role of inflammation in the pathogenesis of Alzheimer's disease (AD). However, the exact role of inflammatory markers in AD is still unclear. OBJECTIVE: The main objective of the current study was to find out the association between the level of inflammatory markers and AD. MATERIAL AND METHODS: The relevant articles have been extracted from PubMed as per the inclusion and exclusion criteria of the study. The mean value with standard deviation and number of participants in AD and control groups were extracted from relevant articles. The inverse variance was used as a statistical method and standard mean difference (SMD) as effect measure with 95% C.I. The random effect model was used and all analyses were done using Rev. Man 5.0. RESULTS: A total of 38 articles have been found relevant and selected for analysis. The overall estimate results have shown that the level of IL-6, TGF-ß1, and IL-1α were increased significantly in AD patients as compared to the control group among all other pro-inflammatory, inflammatory and anti-inflammatory mediators. CONCLUSION: The findings of the current study suggest that IL-6, TGF-ß1, and IL-1α may be a useful early marker in AD. However, further studies are required to confirm the exact utility of these inflammatory markers.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/tratamento farmacológico , Anti-Inflamatórios/uso terapêutico , Biomarcadores , Humanos , Inflamação , Mediadores da Inflamação
16.
PLoS Genet ; 15(3): e1007414, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30845217

RESUMO

While the domestication history of Asian rice has been extensively studied, details of the evolution of African rice remain elusive. The inner Niger delta has been suggested as the center of origin but molecular data to support this hypothesis is lacking. Here, we present a comprehensive analysis of the evolutionary and domestication history of African rice. By analyzing whole genome re-sequencing data from 282 individuals of domesticated African rice Oryza glaberrima and its progenitor O. barthii, we hypothesize a non-centric (i.e. multiregional) domestication origin for African rice. Our analyses showed genetic structure within O. glaberrima that has a geographical association. Furthermore, we have evidence that the previously hypothesized O. barthii progenitor populations in West Africa have evolutionary signatures similar to domesticated rice and carried causal domestication mutations, suggesting those progenitors were either mislabeled or may actually represent feral wild-domesticated hybrids. Phylogeographic analysis of genes involved in the core domestication process suggests that the origins of causal domestication mutations could be traced to wild progenitors in multiple different locations in West and Central Africa. In addition, measurements of panicle threshability, a key early domestication trait for seed shattering, were consistent with the gene phylogeographic results. We suggest seed non-shattering was selected from multiple genotypes, possibly arising from different geographical regions. Based on our evidence, O. glaberrima was not domesticated from a single centric location but was a result of diffuse process where multiple regions contributed key alleles for different domestication traits.


Assuntos
Produtos Agrícolas/genética , Domesticação , Oryza/genética , África Ocidental , Produtos Agrícolas/classificação , DNA de Plantas/genética , Grão Comestível/classificação , Grão Comestível/genética , Variação Genética , Genoma de Planta , Geografia , Oryza/classificação , Filogeografia , Polimorfismo de Nucleotídeo Único , Sementes/genética , Especificidade da Espécie
17.
Environ Toxicol ; 37(8): 1968-1978, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35446454

RESUMO

Iron is an essential metal critical for normal cellular and biochemical function and it is used as a cofactor in many vital biological pathways within the brain. However, accumulation of excess iron in brain is commonly associated with several neurodegenerative and neurotoxic adverse effects. Chronic exposure of iron leads to an increased risk for several neurodegenerative diseases. The exact mechanism of iron-induced neurotoxicity is still unclear. Therefore, our study aimed to investigate the mechanism of neurotoxic and neurodegenerative effects through in vitro exposure of ferrous sulphate in rat C6 cell line. The findings of our study have indicated that ferrous sulphate exposure may lead to induction of molecular markers of neuronal inflammation, apoptotic neuronal cell death, amyloid-beta and hyperphosphorylated tau levels. This study provides a basic mechanistic understanding of signaling pathway and biomarkers involved during iron-induced neurotoxicity.


Assuntos
Ferro , Síndromes Neurotóxicas , Peptídeos beta-Amiloides/metabolismo , Animais , Encéfalo/metabolismo , Linhagem Celular , Ferro/metabolismo , Ferro/toxicidade , Neurônios , Síndromes Neurotóxicas/metabolismo , Ratos
18.
J Sci Food Agric ; 102(14): 6309-6319, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35531753

RESUMO

BACKGROUND: Deficiency of Zn is a major soil constraint in rice plant growth and yield. Edaphic factors such as Zn deficiency in soil in relation to plant performance are still poorly understood. Here, we report promising quantitative trait loci (QTL) conferring tolerance to Zn deficiency, which were identified through biparental mapping. The experiment was conducted using the 236 F7 recombinant inbred line mapping population derived from the cross of Kinandang Patong (Zn deficiency sensitive) and A69-1 (Zn deficiency tolerant). RESULTS: A total of six QTLs (qLB-2B, qLB-4B, qPM-4B, qPM-6B, qRZC-4B, qSZC-4B) on chromosomes 2, 4 and 6 were identified for environment 1, whereas five QTLs (qLB-2 N, qLB-4 N, qPM-4 N, qRZC-4 N, qSZC-4 N) on chromosomes 2 and 4 were detected for environment 2. Among these, five major (51.30, 48.70, 28.60, 56.00, 52.00 > 10 R2 ) and one minor (5.40 < 10 R2 ) QTLs for environment 1 and four major (51.48, 50.20, 53.00, 48.00 > 10 R2 ) and one minor (4.44 < 10) QTLs for environment 2 for Zn deficiency tolerance with a logarithm of odd threshold value higher than 3 were identified. The QTLs (qLB-4B, qPM-4B, qRZC-4B, qSZC-4B, qLB-4 N, qPM-4 N, qRZC-4 N, qSZC-4 N) for leaf bronzing, plant mortality root zinc concentration and shoot zinc concentration identified on chromosome 4 were found to be the most promising and highly reproducible across the locations that explained phenotypic variation from 48.00% to 56.00% with the same marker interval RM6748-RM303. CONCLUSION: The new QTLs and its linked markers identified in the present study can be utilized for Zn deficiency tolerance in elite cultivars using marker-assisted backcrossing. © 2022 Society of Chemical Industry.


Assuntos
Oryza , Locos de Características Quantitativas , Oryza/genética , Fenótipo , Solo , Zinco
19.
Toxicol Mech Methods ; 32(8): 616-627, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35341471

RESUMO

Aluminum is an environmentally abundant potential neurotoxic agent that may result in oxidative damage to a range of cellular biomarkers. The potential sources of aluminum accumulation in the body include drinking water, food, medicines, vaccines, and aluminum cookware utensils, etc. The accumulation of aluminum in the brain is reported to be associated with cholinergic dysfunction, oxidative stress and neuronal damage, which may ultimately cause Alzheimer's disease. Since chronic exposure to aluminum leads to its accumulation in the brain, so this study was done by a long-term (24 weeks) low dose (20 mg/kg) oral exposure of aluminum chloride in rats. In this chronic model, we have evaluated the major hallmarks of Alzheimer's disease including amyloid-beta (Aß1-42) and phosphorylated-tau (p231-tau) protein in brain tissue. Furthermore, we evaluated the level of acetyl cholinesterase activity, inflammatory cytokines such as TNF-α, IL-6 and IL-1ß, and oxidative stress biomarkers in the rat brain in this model. The neurobehavioral parameters were also assessed in animals by using spontaneous locomotor activity, passive avoidance, rotarod test and novel object recognition test to evaluate alteration in learning, memory and muscle co-ordination. We found that chronic oral exposure to aluminum chloride causes a significant increase in structural hallmarks such as Aß1-42 and p231-tau levels along with pro-inflammatory cytokines (TNF-α and IL-6), oxidative stress, and a decrease in antioxidant markers such as GSH and catalase in the brain tissue. These biomarkers significantly affected neurobehavioral parameters in animals. This study provides a mechanistic understanding of chronic aluminum-induced neuronal toxicity in the brain with relevance to Alzheimer's disease.


Assuntos
Doença de Alzheimer , Síndromes Neurotóxicas , Alumínio/toxicidade , Cloreto de Alumínio/toxicidade , Compostos de Alumínio/toxicidade , Doença de Alzheimer/induzido quimicamente , Animais , Biomarcadores/metabolismo , Modelos Animais de Doenças , Interleucina-6/metabolismo , Síndromes Neurotóxicas/etiologia , Estresse Oxidativo , Ratos , Fator de Necrose Tumoral alfa/metabolismo
20.
Plant Biotechnol J ; 19(5): 910-925, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33220119

RESUMO

Rice varieties whose quality is graded as excellent have a lower percent grain chalkiness (PGC) of two per cent and below with higher whole grain yields upon milling, leading to higher economic returns for farmers. We have conducted a genome-wide association study (GWAS) using a combined population panel of indica and japonica rice varieties, and identified a total of 746 single nucleotide polymorphisms (SNPs) that were strongly associated with the chalk phenotype, covered 78 Quantitative Trait Loci (QTL) regions. Among them, 21 were high-value QTLs, as they explained at least 10 % of the phenotypic variance for PGC. A combined epistasis and GWAS was applied to dissect the genetics of the complex chalkiness trait, and its regulatory cascades were validated using gene regulatory networks. Promising novel epistatic interactions were found between the loci of chromosomes 6 (PGC6.1) and 7 (PGC7.8) that contributed to lower PGC. Based on haplotype mining only a few modern rice varieties confounded with a lower chalkiness, and they possess several PGC QTLs. The importance of PGC6.1 was validated through multi-parent advanced generation intercrosses and several low-chalk lines possessing superior haplotypes were identified. The results of this investigation have deciphered the underlying genetic networks that can reduce PGC to 2%, and will thus support future breeding programs to improve the grain quality of elite genetic material with high-yielding potentials.


Assuntos
Oryza , Carbonato de Cálcio , Grão Comestível/genética , Epistasia Genética , Estudo de Associação Genômica Ampla , Oryza/genética , Fenótipo , Melhoramento Vegetal
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