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1.
Plant Mol Biol ; 114(2): 24, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38457044

RESUMO

Soil salinity hampers the survival and productivity of crops. To minimize salt-associated damages in plant, better salt management practices in agriculture have become a prerequisite. Seed priming with different halo-agents is a technique, which improves the primed plant's endurance to tackle sodium. Salt tolerance is achieved in tolerant plants through fundamental physiological mechanisms- ion-exclusion and tissue tolerance, and salt-tolerant plants may (Na+ accumulators) or may not (Na+ excluders) allow sodium movement to leaves. While Na+ excluders depend on ion exclusion in roots, Na+ accumulators are proficient Na+ managers that can compartmentalize Na+ in leaves and use them beneficially as inexpensive osmoticum. Salt-sensitive plants are Na+ accumulators, but their inherent tissue tolerance ability and ion-exclusion process are insufficient for tolerance. Seed priming with different halo-agents aids in 'rewiring' of the salt tolerance mechanisms of plants. The resetting of the salt tolerance mechanism is not universal for every halo-agent and might vary with halo-agents. Here, we review the physiological mechanisms that different halo-agents target to confer enhanced salt tolerance in primed plants. Calcium and potassium-specific halo-agents trigger Na+ exclusion in roots, thus ensuring a low amount of Na+ in leaves. In contrast, Na+-specific priming agents favour processes for Na+ inclusion in leaves, improve plant tissue tolerance or vacuolar sequestration, and provide the greatest benefit to salt-sensitive and sodium accumulating plants. Overall, this review will help to understand the underlying mechanism behind plant's inherent nature towards salt management and its amelioration with different halo-agents, which helps to optimize crop stress performance.


Assuntos
Estresse Salino , Tolerância ao Sal , Folhas de Planta/fisiologia , Salinidade , Sementes , Sódio , Raízes de Plantas , Potássio , Estresse Fisiológico
2.
Am J Surg Pathol ; 48(5): 538-545, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38525831

RESUMO

Drivers of Spitz neoplasms include activating point mutations in HRAS and Spitz-associated genomic fusions. It has become evident that some BRAF -mutated melanocytic neoplasms can morphologically mimic Spitz tumors (STs). These have been termed BRAF mutated and morphologically spitzoid (BAMS). In this study, 17 experts from the International Melanoma Pathology Study Group assessed 54 cases which included 40 BAMS and 14 true STs. The participants reviewed the cases blinded to the genomic data and selected among several diagnostic options, including BAMS, ST, melanoma, and other. A total of 38% of all diagnostic selections in the BAMS cases were for BAMS, whereas 32% were for ST. In 22 of the BAMS cases, the favored diagnosis was BAMS, whereas in 17 of the BAMS cases, the favored diagnosis was ST. Among the 20 cases in the total group of 54 with the highest number of votes for ST, half were BAMS. Of BAMS, 75% had a number of votes for ST that was within the SD of votes for ST seen among true ST cases. There was poor interobserver agreement for the precise diagnosis of the BAMS (kappa = 0.16) but good agreement that these cases were not melanoma (kappa = 0.7). BAMS nevi/tumors can closely mimic Spitz neoplasms. Expert melanoma pathologists in this study favored a diagnosis of ST in nearly half of the BAMS cases. There are BAMS cases that even experts cannot morphologically distinguish from true Spitz neoplasms.


Assuntos
Melanoma , Nevo de Células Epitelioides e Fusiformes , Nevo , Neoplasias Cutâneas , Humanos , Melanoma/diagnóstico , Melanoma/genética , Melanoma/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Proteínas Proto-Oncogênicas B-raf/genética , Nevo de Células Epitelioides e Fusiformes/diagnóstico , Nevo de Células Epitelioides e Fusiformes/genética , Nevo/diagnóstico , Diagnóstico Diferencial
3.
Clin Exp Dermatol ; 48(9): 1081-1083, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37279922
4.
Planta ; 257(6): 111, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37156996

RESUMO

MAIN CONCLUSION: Seed priming with NaCl mimicked the conditions of natural priming to improve the tissue tolerance nature of sensitive legumes, which helps to maintain survivability and yield in mildly saline areas. Seed priming with NaCl is a seed invigoration technique that helps to improve plant growth by altering Na+ and K+ content under salt stress. Legumes are overall sensitive to salt and salinity hampers their growth and yield. Therefore, a priming (50 mM NaCl) experiment was performed with two different legume members [Cicer arietinum cv. Anuradha and Lens culinaris cv. Ranjan] and different morpho-physiological, biochemical responses at 50 mM, 100 mM, and 150 mM NaCl and molecular responses at 150 mM NaCl were studied in hydroponically grown nonprimed and primed members. Similarly, a pot experiment was performed at 80 mM Na+, to check the yield. Tissue Na+ and K+ content suggested NaCl-priming did not significantly alter the accumulation of Na+ among nonprimed and primed members but retained more K+ in cells, thus maintaining a lower cellular Na+/K+ ratio. Low osmolyte content (e.g., proline) in primed members suggested priming could minimize their overall osmolytic requirement. Altogether, these implied tissue tolerance (TT) nature might have improved in case of NaCl-priming as was also reflected by a better TT score (LC50 value). An improved TT nature enabled the primed plants to maintain a significantly higher photosynthetic rate through better stomatal conductance. Along with this, a higher level of chlorophyll content and competent functioning of the photosynthetic subunits improved photosynthetic performance that ensured yield under stress. Overall, this study explores the potential of NaCl-priming and creates possibilities for considerably sensitive members; those in their nonprimed forms have no prospect in mildly saline agriculture.


Assuntos
Cicer , Fabaceae , Lens (Planta) , Cloreto de Sódio/farmacologia , Potássio , Estresse Salino , Sódio , Sementes , Verduras , Íons
5.
Am J Dermatopathol ; 44(12): 984-988, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36197058

RESUMO

ABSTRACT: Histoplasmosis is a dimorphic fungal infection, which is rare outside endemic pockets in North, Central, and South America, Asia, and Africa. Herein, we describe a woman in her 80s living in the Scottish Borders region of the United Kingdom with a recent diagnosis of granulomatous rosacea, who on receiving escalating immunosuppression for suspected sarcoidosis, and long-standing rheumatoid arthritis developed a striking eruption involving her eyelids along with painful ulceration of the oral and nasal mucosa. Histopathologic examination of the skin and mucosal lesions demonstrated granulomatous inflammation with numerous yeast forms of fungal organisms with morphological characteristics of Histoplasma species. This was confirmed to be H. capsulatum on fungal culture and direct panfungal polymerase chain reaction assay. Although the patient had not left the United Kingdom for more than 20 years, she gave a travel history involving multiple trips to countries where histoplasmosis is known to occur, before that. This case exemplifies the challenges involved in making a diagnosis of histoplasmosis in nonendemic regions for both clinicians and pathologists alike. In this particular patient, the diagnostic difficulties were compounded by the clinicopathological overlap with other cutaneous and systemic granulomatous disorders like granulomatous rosacea and suspected sarcoidosis and also the exceptionally long latency period between the purported historical primary infection and recent recrudescence. We highlight this unusual case to increase an awareness of histoplasmosis, which is very rare in nonendemic regions like the United Kingdom and involves cases acquired during residence in or travel to endemic areas, to ensure its prompt recognition and treatment.


Assuntos
Histoplasmose , Rosácea , Sarcoidose , Humanos , Feminino , Histoplasmose/diagnóstico , Histoplasmose/tratamento farmacológico , Sarcoidose/diagnóstico , Reino Unido , Imunossupressores/efeitos adversos , Recidiva
6.
Biometals ; 35(3): 451-478, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35344114

RESUMO

Globally, many people have been suffering from arsenic poisoning. Arsenate (AsV) exposure to twelve rice cultivars caused growth retardation, triggered production of As-chelatin biopeptides and altered activities of antioxidants along with increase in ascorbate (AsA)-glutathione (GSH) contents as a protective measure. The effects were more conspicuous in cvs. Swarnadhan, Tulaipanji, Pusa basmati, Badshabhog, Tulsibhog and IR-20 to attenuate oxidative-overload mediated adversities. Contrastingly, in cvs. Bhutmuri, Kumargore, Binni, Vijaya, TN-1 and IR-64, effects were less conspicuous in terms of alterations in the said variables due to reduced generation of oxidative stress. Under As(V) imposition, the protective role of phytochelatins (PCs) were recorded where peaks height and levels of PCs (PC2, PC3 and PC4) were elevated significantly in the test seedlings with an endeavour to detoxify cells by sequestering arsenic-phytochelatin (As-PC) complex into vacuole that resulted in reprogramming of antioxidants network. Additionally, scatter plot correlation matrices, color-coded heat map analysis and regression slopes demonstrated varied adaptive responses of test cultivars, where cvs. Bhutmuri, Kumargore, Binni, Vijaya, TN-1 and IR-64 found tolerant against As(V) toxicity. Results were further justified by hierarchical clustering. These findings could help to grow identified tolerant rice cultivars in As-prone soil with sustainable growth and productivity after proper agricultural execution.


Assuntos
Arsênio , Oryza , Antioxidantes/metabolismo , Arseniatos/toxicidade , Arsênio/metabolismo , Arsênio/toxicidade , Glutationa/metabolismo , Oryza/metabolismo , Estresse Oxidativo , Fitoquelatinas/metabolismo , Plântula/metabolismo , Compostos de Sulfidrila/metabolismo
7.
Ecotoxicology ; 31(3): 468-489, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35122561

RESUMO

Arsenic contamination of groundwater is a major concern for its usage in crop irrigation in many regions of the world. Arsenic is absorbed by rice plants mainly from arsenic contaminated water during irrigation. It hampers growth and agricultural productivity. The aim of the study was to mitigate the toxic effects of arsenate (As-V) [25 µM, 50 µM, and 75 µM] by silicon (Si) [2 mM] and selenium (Se) [5 µM] amendments on the activity of the TCA cycle, synthesis of γ-aminobutyric acid (GABA) and polyamines (PAs) in rice (Oryza sativa L. cv. MTU-1010) seedlings and to identify which chemical was more potential to combat this threat. As(V) application decreased the activities of tested respiratory enzymes and increased the levels of organic acids (OAs) in the test seedlings. Application of Si with As(V) and Se with As(V) increased the activities of respiratory enzymes and the levels of OAs. The effects were more pronounced during Si amendments. The activities of GABA synthesizing enzymes along with accumulation of GABA were increased under As(V) stress. During joint application of Si with As(V) and Se with As(V) the activity and the level of said parameters were decreased that indicating defensive role of these chemicals to resist As(V) toxicity in rice and Si amendments showed greater potential to reduce As(V) induced damages in the test seedlings. PAs trigger tolerance mechanism against As(V) in plants. PAs such as putrescine, spermidine and spermine were synthesized more during Si and Se amendments in As(V) contaminated rice seedlings to combat the toxic effects of As(V). Si amendments substantially modulated the toxic effects caused by As(V) over Se amendments in the As(V) challenged test seedlings. Thus, in future application of Si enriched fertilizer will be beneficial to grow rice plants with normal vigor in arsenic contaminated soil.


Assuntos
Arsênio , Oryza , Selênio , Poluentes do Solo , Arsênio/análise , Arsênio/toxicidade , Raízes de Plantas , Poliaminas , Plântula , Selênio/farmacologia , Silício/farmacologia , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Ácido gama-Aminobutírico
8.
Int J Phytoremediation ; 24(7): 763-777, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34579603

RESUMO

This study aims to investigate the potentiality of selenium in modulating arsenic stress in rice seedlings. Arsenate accumulation along with its transformation to arsenite was enhanced in arsenate exposed seedlings. Arsenite induced oxidative stress and severely affected the growth of the seedlings. Arsenate exposure caused an elevation in ascorbate and glutathione levels along with the activities of their metabolizing enzymes viz., ascorbate peroxidase, glutathione reductase, glutathione-S-transferase, and glutathione peroxidase. Phytochelatins content was increased under arsenic stress to subdue the toxic effects in the test seedlings. Co-application of arsenate and selenate in rice seedlings manifested pronounced alteration of oxidative stress, antioxidant defense, and thiol metabolism as compared to arsenate treatment only. ANOVA analysis (Tukey's HSD test) demonstrated the relevance of using selenate along with arsenate to maintain the normal growth and development of rice seedlings. Thus, exogenous supplementation of selenium will be a beneficial approach to cultivate rice seedlings in arsenic polluted soil.


Arsenic toxicity in the environment is a global concern, causes chronic signs of poisoning to plants and humans, leads to ecological imbalance. Selenium is known for its antagonistic characteristics and has been found to be effective in combating the adversities of arsenic at low concentrations (5 µM). The present study was performed to explore the comparative responses of rice seedlings during the joint application of selenium and arsenic in terms of growth, generation of oxidative stress, antioxidant defense, and thiol metabolism. Although the molecular basis of arsenic­selenium interaction is widely known a small number of reports were listed about the physio-chemical role of selenium against arsenic stress. Thus, we investigated the influence of selenium to alleviate arsenic-induced toxic effects by modulating the activities of antioxidant enzymes and reducing the levels of oxidative stress markers. It has been noted that selenium regulates thiol metabolism which is known to play a key role in growth preservation by restriction of arsenic translocation. The outcome from the study would be useful in field trials for sustainable agriculture in arsenic-contaminated soil.


Assuntos
Arsênio , Arsenitos , Oryza , Selênio , Antioxidantes/metabolismo , Arseniatos/metabolismo , Arseniatos/toxicidade , Arsênio/metabolismo , Arsênio/toxicidade , Arsenitos/metabolismo , Arsenitos/toxicidade , Biodegradação Ambiental , Glutationa/metabolismo , Glutationa/farmacologia , Oryza/metabolismo , Estresse Oxidativo , Plântula , Ácido Selênico/metabolismo , Ácido Selênico/farmacologia , Selênio/metabolismo , Selênio/farmacologia , Compostos de Sulfidrila/metabolismo
9.
Environ Sci Pollut Res Int ; 29(13): 19508-19529, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34719761

RESUMO

Arsenic (As) in groundwater severely harms global economic development by affecting growth and productivity of agricultural crops that causes human health risk. The comparative influence of silicon (Si) and selenium (Se) to modulate pigments levels, photosynthetic parameters using LI-6400XT Portable Photosynthesis System and carbohydrate metabolism under arsenate (As-V) stress in rice cv. MTU-1010 were evaluated. As(V) stress significantly decreased chlorophyll-a (32% on an average), chlorophyll-b (58% on an average), total chlorophyll (46% on an average), fluorescence intensity (31% on an average), carotene (39% on an average), xanthophyll (33% on an average), Hill activity (47% on an average) and the photosynthetic parameters, viz. intercellular CO2 concentration (52% on an average), net photosynthesis (54% on an average), transpiration rate (36% on an average) and stomatal conductance (38% on an average) in the test seedlings. As(V) + Si treatments enhanced the stated occurrences more than As(V) + Se treatments in rice seedlings. Sugar contents, viz. reducing (85% on an average) and non-reducing sugar (61% on an average), were increased, but starch content (57% on an average) was decreased in only As(V)-treated rice seedlings. The activities of carbohydrate metabolizing enzymes were increased, while sucrose synthase activity was decreased due to As(V) toxicity in the test seedlings. Co-application of Si and As(V) as well as Se and As(V) showed ameliorative effects on sugar and starch contents along with the activities of carbohydrate metabolizing enzymes, but more potential effect was observed under combined application of Si and As(V) in rice seedlings. Thus, it is an important purpose of this paper to compare the ability of Se and Si to alleviate As(V) toxicity in rice seedlings which will be an effective approach to develop possible strategies in As-contaminated agricultural soil to improve normal growth and productivity of rice plants.


Assuntos
Arsênio , Oryza , Selênio , Arsênio/metabolismo , Metabolismo dos Carboidratos , Cloroplastos/metabolismo , Humanos , Oryza/metabolismo , Fotossíntese , Plântula/metabolismo , Selênio/metabolismo , Silício/metabolismo , Silício/farmacologia
10.
Plant Physiol Biochem ; 166: 41-52, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34090120

RESUMO

Polyamines (PA) have multifarious roles in plant-environment interaction and stress responses. In conjunction with GABA shunt, they regulate induction of tolerance under salinity stress in plants. Here, we tested the hypothesis that silicon improves salt tolerance through mediating vital metabolic pathways rather than acting as a mere mechanical barrier. Seedlings of two rice (Oryza sativa L.) cultivars MTU 1010 (salt-sensitive) & Nonabokra (salt-tolerant) growing in hydroponic culture were treated with NaCl (0, 25, 50 & 100 mM) combined with or without Si (2 mM). NaCl stress enhanced PA synthesizing enzymes activity and PA production in salt tolerant cultivar Nonabokra, whereas in the sensitive cultivar, MTU 1010 both declined. Enhanced activities of GABA synthesizing enzymes along with a decline in the activities of GABA degrading enzymes under NaCl exposure led to GABA accumulation in both the cultivars. The interactive effects of silicon and NaCl also induced the activities of the enzymes related to polyamine biosynthesis and inhibited polyamine degrading enzymes that enhanced PA contents in the cultivars. Supplemental Si decreased endogenous GABA levels by modulating GABA metabolising enzymes under NaCl stress. On the basis of all tested parameters cv. MTU 1010 was proven to be more responsive towards silicon application than cv. Nonabokra. Such study of silicon-induced polyamine accretion and reduced GABA accumulation may lower oxidative damage in rice cultivars under NaCl stress and thereby form a successful strategy to boost tolerance.


Assuntos
Oryza , Tolerância ao Sal , Poliaminas , Silício/farmacologia , Ácido gama-Aminobutírico
12.
J Cutan Pathol ; 48(2): 309-313, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32623745

RESUMO

We present a case of trichoblastic carcinosarcoma with panfollicular differentiation. An 80-year-old man presented with a lesion on the left ear, which had been present for several months. Histopathology revealed a well-demarcated neoplasm in the dermis composed of intimately intermingled malignant epithelial and mesenchymal cells. The epithelial component showed multilineage follicular differentiation toward all of the elements of a normal hair follicle. Molecular analysis revealed identical molecular aberrations in both epithelial and mesenchymal components including CTNNB1 and SUFU mutations. To the best of our knowledge, this is the first report of panfollicular carcinosarcoma and of the presence of a CTNNB1 mutation in trichoblastic carcinosarcoma.


Assuntos
Carcinossarcoma , Mutação , Proteínas de Neoplasias , Neoplasias Cutâneas , beta Catenina , Idoso de 80 Anos ou mais , Carcinossarcoma/genética , Carcinossarcoma/metabolismo , Carcinossarcoma/patologia , Humanos , Masculino , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , beta Catenina/genética , beta Catenina/metabolismo
13.
Am J Dermatopathol ; 42(12): 1004-1005, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33289980
14.
Am J Dermatopathol ; 42(12): e161-e162, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33289983
15.
Environ Sci Pollut Res Int ; 27(36): 45209-45224, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32779070

RESUMO

A hydroponic experiment was conducted to establish the response of exogenous silicon [Si] in alleviating arsenate [As (V)] prompted alterations on antioxidant enzyme activities and thiol metabolism in wheat (Triticum aestivum L. cv PBW 343) seedlings. Objective of the work was to validate the hypothesis whether silicate may alleviate arsenate-provoked oxidative stress in wheat through diverse metabolic pathways with an endeavor to improve food safety and health. Arsenate treatment significantly enhanced oxidative stress and was associated with modifications in non-enzymatic and enzymatic antioxidants. The activities of arsenate reductase [AR] and the enzymes related to thiol metabolism revealed dose-dependent enhancements with increase in arsenate along with enhanced production of phytochelatins [PCs] in the cultivar. Simultaneous supplementations of silicate with arsenate in the nutrient formulation reduced arsenate uptake along with arsenate reductase activity and consequently lowered arsenite [As (III)] accumulation. The antioxidative defense was upregulated and phytochelatin production was lowered causing an appreciable revival from the arsenate-imposed consequences that eventually augmented growth.


Assuntos
Arsênio , Plântula , Antioxidantes , Estresse Oxidativo , Silício , Compostos de Sulfidrila , Triticum
16.
Protoplasma ; 257(6): 1559-1583, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32647999

RESUMO

Salinity hinders agricultural productivity worldwide by distressing plant metabolism. Growth of blackgram (Vigna mungo L. var. Sulata), an adverse climate-resistant pulse, is arrested under salinity. Present research integrates study of physio-biochemical parameters and non-targeted metabolomics approach to explore the alterations in metabolic pathway during adaptive responses of nonprimed and haloprimed blackgram seedlings grown hydroponically under NaCl stress. Salinity provoked accumulation of peroxides, compatible solutes and phenolics which increased free radical scavenging activities of nonprimed seedlings under salinity. Pre-germination seed halopriming abrogated NaCl-mediated adversities in haloprimed plantlets favouring better growth. Thus, farmers may adopt seed halopriming technique to improve blackgram productivity in saline-prone fields. Additionally, metabolomics study uncovered numerous metabolites amongst which 35 compounds altered significantly under salinity. The candidate metabolites were aspartic acid, L-glutamic acid, L-proline, L-asparagine, DL-isoleucine, L-homoserine, citrulline, L-ornithine, D-altrose, D-allose, N-acetyl-D-mannosamine, fructose, tagatose, sucrose, D-glucose, maltose, glycerol-1-phosphate, D-sorbitol, benzoic acid, shikimic acid, 4-hydroxycinnamic acid, arbutin, succinic acid, pipecolic acid, fumaric acid, nicotinic acid, L-pyroglutamic acid, oxalic acid, glyceric acid, maleamic acid, adenine, guanosine, lauric acid, stearic acid and porphine. Comparing metabolic responses of nonprimed and haloprimed seedlings, it was clear that efficient alteration in carbohydrate metabolism, phenolics accumulation, amino acid, organic acid and nucleic acid metabolism were the key places of metabolic reprogramming for tolerating salinity. Overall, we report, for the first time, 35 contributory candidate compounds that constituted core fundamental metabolome invoking salinity tolerance in nonprimed and haloprimed blackgram. These metabolites may be targeted by biotechnologists to produce high vigour salt-tolerant transgenic blackgram via genetic engineering.


Assuntos
Metabolômica/métodos , Plântula/química , Cloreto de Sódio/química , Vigna/química
17.
Ecotoxicology ; 29(7): 912-931, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32594380

RESUMO

Influence of arsenic (As) in As tolerant and sensitive rice genotypes based chloroplastic pigments, leaf gas exchange attributes and their influence on carbohydrate metabolism were investigated in the present study. As retards growth of crop plants and increase several health ailments by contaminating food chain. Photosynthetic inhibition is known to be the prime target of As toxicity due to over-production of ROS. Hydroponically grown rice seedlings of twelve cultivars were exposed to 25, 50, and 75 µM arsenate (AsV) that exerted negative impact on plastidial pigments content and resulted into inhibition of Hill activity. Internal CO2 concentration lowered gradually due to interference of As with stomatal conductance and transpiration rate that subsequently led to drop in net photosynthesis. Twelve contrasting rice genotypes responded differentially to As(V) stress. Present study evaluated As tolerant and sensitive rice cultivars with respect to As(V) imposed alterations in pigments content, photosynthetic attributes along with sugar metabolism. Starch contents, the principle carbohydrate storage declined differentially among As(V) stressed test cultivars, being more pronounced in cvs. Swarnadhan, Tulaipanji, Pusa basmati, Badshabhog, Tulsibhog and IR-20 compared to cvs. Bhutmuri, Kumargore, Binni, Vijaya, TN-1 and IR-64. Therefore, the six former cultivars tried to adapt defensive mechanisms by accumulating higher levels of reducing and non-reducing sugars to carry out basal metabolism to withstand As(V) induced alterations in photosynthesis. This study could help to screen As tolerant and sensitive rice genotypes based on their photosynthetic efficiency in As polluted agricultural fields to reduce As contamination assisted ecotoxicological risk.


Assuntos
Arseniatos/efeitos adversos , Metabolismo dos Carboidratos/efeitos dos fármacos , Oryza/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Poluentes do Solo/efeitos adversos , Genótipo , Oryza/genética , Oryza/fisiologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Estresse Fisiológico
18.
Am J Dermatopathol ; 42(3): 165-172, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31503010

RESUMO

AIMS: Neurofibromas (NFs) and melanocytic nevi share a common neuroectodermal origin and may occasionally show overlapping morphological features. The objective of this study was to assess the prevalence and spectrum of melanocytic proliferation/differentiation in NFs and also to test the hypothesis whether detection of this feature could be used as a potential clue for neurofibromatosis type 1 (NF-1). METHODS: This was a retrospective study of 229 syndromic and 239 sporadic cutaneous NFs. Each case was assessed for an associated melanocytic component, both within the tumor and the overlying epidermis. Melan A immunohistochemistry was used in selected cases to further characterize this feature, particularly in diffuse NFs. RESULTS: An associated melanocytic component was detected in 77/229 syndromic and 12/239 sporadic cases (P < 0.00001). This was in the form of a junctional proliferation (lentiginous melanocytic hyperplasia or junctional nevus) or dermal differentiation (diffuse spindle cell or dermal nests of pigmented epithelioid melanocytes). CONCLUSIONS: Our study affirms that the spectrum of melanocytic proliferation/differentiation in NFs is broad and probably under-recognized. Awareness of this phenomenon is critical to avoid misdiagnosis of some diffuse NFs as primary melanocytic tumors, for example, desmoplastic melanomas. Given the strong link between dermal melanocytic differentiation and syndromic NFs, its detection could potentially serve as a useful clue for NF-1 in an appropriate clinical context.


Assuntos
Melanócitos/patologia , Neurofibroma/patologia , Neoplasias Cutâneas/patologia , Adulto , Idoso , Diferenciação Celular , Proliferação de Células , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurofibromatose 1/patologia , Estudos Retrospectivos
19.
Ecotoxicology ; 29(1): 13-34, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31735977

RESUMO

Arsenic (As) accumulation in rice is a principal route of As exposure for rice based population. We have tested physiochemical and molecular parameters together to identify low As accumulating rice cultivars with normal growth and vigor. The present study examined potential toxicity caused by arsenate (AsV) among four rice cultivars tested that varied with respect to accumulation of total arsenic, arsenite (AsIII) and their differential translocation rate which had deleterious impact on growth and metabolism. Intracellular homeostasis of rice cultivars viz., TN-1, IR-64, IR-20 and Tulaipanji was hampered by 21 days long As(V) treatment due to generation of reactive oxygen species (ROS) and inadequate activity of catalase (CAT; EC 1.11.1.6). Upregulation of oxidative stress markers viz., H2O2, proline and MDA along with alteration in enzymatic antioxidants profile were conspicuously pronounced in cv. Tulaipanji while cv. TN-1 was least affected under As(V) challenged environment. In addition to that genomic template stability and band sharing indices were qualitatively measured by DNA profiling of all tested cultivars treated with 25 µM, 50 µM, and 75 µM As(V). In rice cv. Tulaipanji genetic polymorphism was significantly detected with the application of random amplified polymorphic DNA (RAPD) tool and characterized as susceptible cultivar of As compared to cvs. TN-1, IR-64 and IR-20 that is in correlation with data obtained from cluster analysis. Hence, identified As tolerant cultivars viz., TN-1, IR64 and IR-20 especially TN-1 could be used in As contaminated agricultural field after appropriate field trial. This study could help to gather information regarding cultivar-specific tolerance strategy to avoid pollutant induced toxicity.


Assuntos
Arsênio/toxicidade , Oryza/fisiologia , Poluentes do Solo/toxicidade , Catalase/metabolismo , Instabilidade Genômica , Peróxido de Hidrogênio/metabolismo , Oryza/efeitos dos fármacos , Oryza/genética , Estresse Oxidativo
20.
J Cutan Pathol ; 47(5): 431-438, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31859431

RESUMO

BACKGROUND: Granular cell tumors (GCTs) are uncommon mucocutaneous and soft tissue neoplasms with distinctive histopathologic appearance but controversial histogenesis. Herein, we report a variant of cutaneous GCT featuring extensive desmoplastic stroma which may result in diagnostic difficulties with mesenchymal proliferations, particularly a dermatofibroma. METHODS: Following a recent case of GCT with prominent stromal desmoplasia, we reviewed all cases diagnosed as GCT during the past 10 years accessioned at the dermatopathology unit in a tertiary university hospital. RESULTS: Three additional cases with a similar excessive connective tissue were identified out of a total of 49 GCTs. Cytoplasmic granularity was often subtle and focal, S100 expression was weak, and nuclei had a tendency to show spindling in tumor cells entrapped within the desmoplastic areas. Of note, nuclear spindling is one of the criteria used to diagnose an atypical/malignant GCT. CONCLUSION: We propose the term "desmoplastic GCT" for these tumors, which not only appropriately addresses the stromal changes but also raises an awareness of GCT being one of the cutaneous tumors which may show stromal desmoplasia. Differential diagnostic difficulties apart, awareness of this phenomenon is important so that desmoplasia and resultant spindling are not linked with potential aggressive behavior.


Assuntos
Biomarcadores Tumorais/metabolismo , Núcleo Celular/ultraestrutura , Tumor de Células Granulares/patologia , Neoplasias de Tecidos Moles/patologia , Adulto , Idoso , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Conscientização , Núcleo Celular/patologia , Diagnóstico Diferencial , Feminino , Seguimentos , Tumor de Células Granulares/metabolismo , Tumor de Células Granulares/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias de Tecido Fibroso/patologia , Prognóstico , Proteínas S100/metabolismo , Neoplasias Cutâneas/patologia , Resultado do Tratamento
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