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1.
Trends Plant Sci ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39025750

RESUMO

The intricate regulation of flowering time in response to day length has been extensively shown. A recent study has now revealed a similar mechanism for regulating vegetative growth. Wang et al. observed that plants measure daylength as the duration of photosynthesis and metabolite production to modulate vegetative growth.

2.
Int Microbiol ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819732

RESUMO

The scarce antifungal arsenal, changes in the susceptibility profile of fungal agents, and lack of adherence to treatment have contributed to the increase of cases of dermatomycoses. In this context, new antimicrobial substances have gained importance. Chalcones are precursors of the flavonoid family that have multiple biological activities, have high tolerability by humans, and easy synthesis. In this study, we evaluated the in vitro antifungal activity, alone and in combination with conventional antifungal drugs, of the VS02-4'ethyl chalcone-derived compound against dermatophytes and Candida spp. Susceptibility testing was carried out by broth microdilution. Experiments for determination of the target of the compound on the fungal cell, time-kill kinetics, and toxicity tests in Galleria mellonella model were also performed. Combinatory effects were evaluated by the checkerboard method. Results showed high activity of the compound VS02-4'ethyl against dermatophytes (MIC of 7.81-31.25 µg/ml). The compound targeted the cell membrane, and the time-kill test showed the compound continues to exert gradual activity after 5 days on dermatophytes, but no significant activity on Candida. Low toxicity was observed at 250 mg/kg. Excellent results were observed in the combinatory test, where VS02-4'ethyl showed synergistic interactions with itraconazole, fluconazole, terbinafine, and griseofulvin, against all isolates tested. Although further investigation is needed, these results revealed the great potential of chalcone-derived compounds against fungal infections for which treatments are long and laborious.

3.
Trends Plant Sci ; 29(4): 388-390, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38102047

RESUMO

Aluminum (Al) toxicity is a crucial limiting factor for crop growth in acid soils. Recently, Liu et al. demonstrated that the root microbiota of rice modulates the responses to Al toxicity and phosphorus limitation, offering intriguing insights into microbiome function and opening new research opportunities.


Assuntos
Microbiota , Oryza , Solo , Plantas , Fósforo , Alumínio , Concentração de Íons de Hidrogênio , Raízes de Plantas
4.
Trends Plant Sci ; 29(6): 607-609, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38135605

RESUMO

Fluctuations in temperature severely impact crop yield and trigger various plant response mechanisms. In a recent study, Zhou et al. discovered a non-canonical role of autophagy in mediating Golgi apparatus restoration after short-term heat stress (HS). Their results further suggest a critical, yet previously unknown, mechanism of autophagy-related (ATG)-8 in Golgi reassembly after HS.


Assuntos
Autofagia , Complexo de Golgi , Resposta ao Choque Térmico , Complexo de Golgi/metabolismo , Complexo de Golgi/fisiologia , Autofagia/fisiologia , Resposta ao Choque Térmico/fisiologia , Temperatura Alta
5.
J Plant Physiol ; 292: 154163, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38118303

RESUMO

Stomata, small hydromechanical valves in the leaf epidermis, are fundamental in regulating gas exchange and water loss between plants and the environment. Stomatal development involves a series of coordinated events ranging from the initial cell division that determines the meristemoid mother cells to forming specialized structures such as guard cells. These events are orchestrated by the transcription factors SPEECHLESS, FAMA, and MUTE through signaling networks. The role of plant hormones (e.g., abscisic acid, jasmonic acid, and brassinosteroids) in regulating stomatal development has been elucidated through these signaling cascades. In addition, environmental factors, such as light availability and CO2 concentration, also regulate the density and distribution of stomata in leaves, ultimately affecting overall water use efficiency. In this review, we highlight the mechanisms underlying stomatal development, connecting key signaling processes that activate or inhibit cell differentiation responsible for forming guard cells in the leaf epidermis. The factors responsible for integrating transcription factors, hormonal responses, and the influence of climatic factors on the signaling network that leads to stomatal development in plants are further discussed. Understanding the intricate connections between these factors, including the metabolic regulation of plant development, may enable us to maximize plant productivity under specific environmental conditions in changing climate scenarios.


Assuntos
Folhas de Planta , Estômatos de Plantas , Estômatos de Plantas/fisiologia , Folhas de Planta/metabolismo , Plantas/metabolismo , Água/metabolismo , Fatores de Transcrição/metabolismo , Células Epidérmicas/metabolismo
6.
Int Microbiol ; 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37875749

RESUMO

Onychomycosis is a nail infection caused by dermatophytes, non-dermatophyte fungi, and yeasts, especially Candida species. The present study evaluated the combinatorial effect of different cultured extracts of Candida parapsilosis and Trichophyton mentagrophytes and Trichophyton rubrum with fluconazole, itraconazole, and terbinafine against clinical isolates of Trichophyton rubrum. In addition, investigation of the action of the extracts on the wall or membrane was performed. Pure and mixed cultures of Candida parapsilosis and dermatophytes were filtered through a 0.2-µm membrane and submitted to liquid-liquid extraction using ethyl acetate. After a checkerboard, trial with drugs was performed to evaluate the synergistic interaction with the extract. The results obtained for the minimum inhibitory concentration (MIC) of extracts against the T. rubrum strain in isolation were 500-8000 µg/mL. The MIC range for fluconazole, itraconazole, and terbinafine were 2-32 µg/mL, 0.25-0.5 µg/mL, 0.03-64 µg/mL, respectively. However, when the extract was combined with drugs, the MIC values decreased: extracts 1.9-1000 µg/mL, fluconazole 0.25-4, itraconazole 0.03-0.06 µg/mL, and terbinafine 0.001-0.02 µg/mL. The MIC values of the extracts in the Roswell Park Memorial Institute 1640 medium (RPMI) supplemented with sorbitol did not change, suggesting any action on the cell wall. However, in the presence of RPMI supplemented with ergosterol, MIC values of the extracts increased by up to 2×, indicating action on the fungal cell membrane. A synergistic action was observed between products and drugs, detecting a decrease in MIC values. There is potential and a new therapeutic perspective for fungal control.

8.
Trends Plant Sci ; 28(10): 1092-1094, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37407411

RESUMO

The elucidation and removal of photorespiratory metabolic constraints will be necessary to improve crop yield in the next agricultural revolution. Fu et al. studied metabolic fluxes in the photorespiratory pathway and report that serine is the major export, whereas dynamic alterations in glycine pools orchestrate CO2 assimilation during the induction and relaxation of photorespiration.


Assuntos
Glicina , Fotossíntese , Glicina/metabolismo , Serina/metabolismo , Respiração Celular , Folhas de Planta/metabolismo , Dióxido de Carbono/metabolismo
9.
Trends Plant Sci ; 28(10): 1113-1123, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37268488

RESUMO

For over 2500 years, considerable agronomic interest has been paid to soil fertility. Both crop domestication and the Green Revolution shifted photoperiodism and the circadian clock in cultivated species, although this contributed to an increase in the demand for chemical fertilisers. Thus, the uptake of nutrients depends on light signalling, whereas diel growth and circadian rhythms are affected by nutrient levels. Here, we argue that day length and circadian rhythms may be central regulators of the uptake and usage of nutrients, also modulating responses to toxic elements (e.g., aluminium and cadmium). Thus, we suggest that knowledge in this area might assist in developing next-generation crops with improved uptake and use efficiency of nutrients.


Assuntos
Relógios Circadianos , Fotoperíodo , Ritmo Circadiano/fisiologia , Produtos Agrícolas
10.
Heliyon ; 9(6): e16634, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37313173

RESUMO

Dengue, like other arboviruses with broad clinical spectra, can easily be misdiagnosed as other infectious diseases due to the overlap of signs and symptoms. During large outbreaks, severe dengue cases have the potential to overwhelm the health care system and understanding the burden of dengue hospitalizations is therefore important to better allocate medical care and public health resources. A machine learning model that used data from the Brazilian public healthcare system database and the National Institute of Meteorology (INMET) was developed to estimate potential misdiagnosed dengue hospitalizations in Brazil. The data was modeled into a hospitalization level linked dataset. Then, Random Forest, Logistic Regression and Support Vector Machine algorithms were assessed. The algorithms were trained by dividing the dataset in training/test set and performing a cross validation to select the best hyperparameters in each algorithm tested. The evaluation was done based on accuracy, precision, recall, F1 score, sensitivity, and specificity. The best model developed was Random Forest with an accuracy of 85% on the final reviewed test. This model shows that 3.4% (13,608) of all hospitalizations in the public healthcare system from 2014 to 2020 could have been dengue misdiagnosed as other diseases. The model was helpful in finding potentially misdiagnosed dengue and might be a useful tool to help public health decision makers in planning resource allocation.

11.
Trends Plant Sci ; 28(5): 597-608, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36822959

RESUMO

Through domestication of wild species, humans have induced large changes in the developmental and circadian clocks of plants. As a result of these changes, modern crops are more productive and adaptive to contrasting environments from the center of origin of their wild ancestors, albeit with low genetic variability and abiotic stress tolerance. Likewise, a complete restructuring of plant metabolic timekeeping probably occurred during crop domestication. Here, we highlight that contrasting timings among organs in wild relatives of crops allowed them to recognize environmental adversities faster. We further propose that connections among biological clocks, which were established during plant domestication, may represent a fundamental source of genetic variation to improve crop resilience and yield.


Assuntos
Relógios Biológicos , Produtos Agrícolas , Humanos , Produtos Agrícolas/genética , Domesticação
13.
Med Mycol ; 61(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36535634

RESUMO

Sporotrichosis is a subcutaneous mycosis that affects animals and humans. Varying in severity, occurrences range from local lesions to systemic involvement. It is caused by thermodimorphic and saprobic fungi from the Sporothrix pathogenic clade. This study aimed to identify the species and the sexual idiomorph distribution patterns responsible for diagnosed cases of sporotrichosis in São José do Rio Preto, Brazil. We included 188 isolates of Sporothrix sp. from feline lesions and 27 of human origin, which underwent molecular identification and genotyping for mating-type MAT1-1 and MAT1-2. The results showed that Sporothrix brasiliensis is the prevalent species in feline sporotrichosis outbreaks with the overwhelming presence of a single mating-type, MAT1-2 (P <.0001), suggesting a prevalently clonal form of spread. Morphological analyses did not discriminate among cryptic species in the genus Sporothrix, and molecular identification was essential for the correct identification of the species responsible for the observed cases of sporotrichosis. Distribution analyses of MAT1-2 isolates support the hypothesis of unidirectional migration from the current epidemics in São Paulo and Rio de Janeiro to the municipality of São José do Rio Preto.


This study aimed to identify the species and the sexual idiomorph distribution patterns responsible for diagnosed cases of sporotrichosis in São José do Rio Preto, Brazil. We included 188 isolates of Sporothrix sp. from feline lesions and 27 of human origin.


Assuntos
Doenças do Gato , Dermatomicoses , Sporothrix , Esporotricose , Humanos , Animais , Gatos , Esporotricose/epidemiologia , Esporotricose/veterinária , Esporotricose/microbiologia , Brasil/epidemiologia , Dermatomicoses/epidemiologia , Dermatomicoses/veterinária , Surtos de Doenças , Doenças do Gato/epidemiologia
14.
J Biotechnol ; 359: 1-14, 2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-36126804

RESUMO

Photosynthesis is responsible for the primary productivity and maintenance of life on Earth, boosting biological activity and contributing to the maintenance of the environment. In the past, traditional crop improvement was considered sufficient to meet food demands, but the growing demand for food coupled with climate change has modified this scenario over the past decades. However, advances in this area have not focused on photosynthesis per se but rather on fixed carbon partitioning. In short, other approaches must be used to meet an increasing agricultural demand. Thus, several paths may be followed, from modifications in leaf shape and canopy architecture, improving metabolic pathways related to CO2 fixation, the inclusion of metabolic mechanisms from other species, and improvements in energy uptake by plants. Given the recognized importance of photosynthesis, as the basis of the primary productivity on Earth, we here present an overview of the latest advances in attempts to improve plant photosynthetic performance. We focused on points considered key to the enhancement of photosynthesis, including leaf shape development, RuBisCO reengineering, Calvin-Benson cycle optimization, light use efficiency, the introduction of the C4 cycle in C3 plants and the inclusion of other CO2 concentrating mechanisms (CCMs). We further provide compelling evidence that there is still room for further improvements. Finally, we conclude this review by presenting future perspectives and possible new directions on this subject.


Assuntos
Ribulose-Bifosfato Carboxilase , Biologia Sintética , Ribulose-Bifosfato Carboxilase/metabolismo , Dióxido de Carbono/metabolismo , Fotossíntese , Plantas/metabolismo , Carbono/metabolismo
15.
Trends Plant Sci ; 27(11): 1084-1086, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35973903

RESUMO

Nitrogen (N) nutrition and meiosis demand large amounts of energy and widely affect crop yield. Recently, Yang and colleagues connected both processes by demonstrating that meiosis initiation depends on the electron-transfer flavoprotein/electron-transfer flavoprotein:ubiquinone oxidoreductase (ETF/ETFQO) system, whereas meiotic defects of the etfß mutant can be rescued using N supplementation.


Assuntos
Aminoácidos , Ubiquinona , Aminoácidos/metabolismo , Meiose/genética , Nitrogênio , Sementes/genética , Sementes/metabolismo
16.
Pathog Immun ; 7(1): 49-59, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35795726

RESUMO

Background: Ultraviolet light in the UV-C band is also known as germicidal radiation, and it is widely used for decontamination and disinfection of environments, water, and food. The ultraviolet source transfers electromagnetic energy from a mercury arc lamp to an organism's genetic material. When UV radiation penetrates the cell wall of an organism, it destroys the cell's ability to reproduce, through a physical and not chemical process. Thus, the objective of this study was to evaluate the antimicrobial potential of a new UV-C generating device (Asepsis) against clinically important microorganisms that may be present in beauty centers. Methods: We present here a set of tests performed on tools easy to find in beauty salons (hair-brushes, nail pliers, makeup brushes, and, due to the recent COVID-19 pandemic, face mask samples). They were individually contaminated with bacteria (Pseudomonas aeruginosa, Staphylococcus aureus), fungi (Microsporum canis, Trichophyton rubrum, Candida albicans, Malassezia furfur), and the Chikungunya virus. Different times of exposure were evaluated (1, 3, and 5 minutes). Results: There was notable reduction in the microbial load in every test, in comparison with control groups. Best results were observed on face mask samples, while the makeup brush showed less reduction, even with longer periods of exposure. Conclusions: Beauty salons present a risk of infections due to microbial exposure. The device tested can efficiently inactivate, in a short time, microorganisms contaminating most tools found in this setting. The device also showed promising results against enveloped virus.

17.
J Exp Bot ; 73(12): 4113-4128, 2022 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-35383842

RESUMO

Auxin is an important hormone playing crucial roles during fruit growth and ripening; however, the metabolic impact of changes in auxin signalling during tomato (Solanum lycopersicum L.) ripening remains unclear. Here, we investigated the significance of changes in auxin signalling during different stages of fruit development by analysing changes in tomato fruit quality and primary metabolism using mutants with either lower or higher auxin sensitivity [diageotropica (dgt) and entire mutants, respectively]. Altered auxin sensitivity modifies metabolism, through direct impacts on fruit respiration and fruit growth. We verified that the dgt mutant plants exhibit reductions in fruit set, total fruit dry weight, fruit size, number of seeds per fruit, and fresh weight loss during post-harvest. Sugar accumulation was associated with delayed fruit ripening in dgt, probably connected with reduced ethylene levels and respiration, coupled with a lower rate of starch degradation. In contrast, despite exhibiting parthenocarpy, increased auxin perception (entire) did not alter fruit ripening, leading to only minor changes in primary metabolism. By performing a comprehensive analysis, our results connect auxin signalling and metabolic changes during tomato fruit development, indicating that reduced auxin signalling led to extensive changes in sugar concentration and starch metabolism during tomato fruit ripening.


Assuntos
Solanum lycopersicum , Ciclofilinas/genética , Etilenos/metabolismo , Frutas , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Solanum lycopersicum/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Amido/metabolismo , Açúcares/metabolismo
18.
J Hazard Mater ; 432: 128704, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35313159

RESUMO

Aluminium (Al), a limiting factor for crop productivity in acidic soils (pH ≤ 5.5), imposes drastic constraints for food safety in developing countries. The major mechanisms that allow plants to cope with Al involve manipulations of organic acids metabolism and DNA-checkpoints. When assumed individually both approaches have been insufficient to overcome Al toxicity. On analysing the centre of origin of most cultivated plants, we hypothesised that day-length seems to be a pivotal agent modulating Al tolerance across distinct plant species. We observed that with increasing distance from the Equator, Al tolerance decreases, suggesting a relationship with the photoperiod. We verified that long-day (LD) species are generally more Al-sensitive than short-day (SD) species, whereas genetic conversion of tomato for SD growth habit boosts Al tolerance. Reduced Al tolerance correlates with DNA-checkpoint activation under LD. Furthermore, DNA-checkpoint-related genes are under positive selection in Arabidopsis accessions from regions with shorter days, suggesting that photoperiod act as a selective barrier for Al tolerance. A diel regulation and genetic diversity affect Al tolerance, suggesting that day-length orchestrates Al tolerance. Altogether, photoperiodic control of Al tolerance might contribute to solving the historical obstacle that imposes barriers for developing countries to reach a sustainable agriculture.


Assuntos
Arabidopsis , Fotoperíodo , Alumínio/toxicidade , Arabidopsis/metabolismo , DNA , Regulação da Expressão Gênica de Plantas , Plantas/metabolismo
19.
J Hazard Mater ; 430: 128366, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35168102

RESUMO

Acidic soils are a major limiting factor for food production in many developing countries. High concentrations of soluble Al cations, particularly Al3+, inhibit cell division and root elongation in plants. Al3+ damages several biomolecules, including DNA, impairing gene expression and cell cycle progression. Notably, the loss-of-function mutants of DNA checkpoints may mediate Al tolerance. Furthermore, mitochondrial organic acids play key roles in neutralizing Al3+ within the cell and around the rhizosphere. Here, we provide knowledge synthesis on interactions between checkpoints related to mitochondrial organic acid homeostasis and DNA integrity mediating Al tolerance in land plants. These interactions, coupled with remarkable advances in tools related to metabolism and cell cycle, may facilitate the development of next-generation productive crops under Al toxicity.


Assuntos
Alumínio , Solo , Produtos Agrícolas , DNA , Raízes de Plantas/metabolismo , Rizosfera
20.
Plant Commun ; 3(1): 100246, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-35059627

RESUMO

Efficient use of natural resources (e.g., light, water, and nutrients) can be improved with a tailored developmental program that maximizes the lifetime and fitness of plants. In plant shoots, a developmental phase represents a time window in which the meristem triggers the development of unique morphological and physiological traits, leading to the emergence of leaves, flowers, and fruits. Whereas developmental phases in plant shoots have been shown to enhance food production in crops, this phenomenon has remained poorly investigated in roots. In light of recent advances, we suggest that root development occurs in three main phases: root apical meristem appearance, foraging, and senescence. We provide compelling evidence suggesting that these phases are regulated by at least four developmental pathways: autonomous, non-autonomous, hormonal, and periodic. Root developmental pathways differentially coordinate organ plasticity, promoting morphological alterations, tissue regeneration, and cell death regulation. Furthermore, we suggest how nutritional checkpoints may allow progression through the developmental phases, thus completing the root life cycle. These insights highlight novel and exciting advances in root biology that may help maximize the productivity of crops through more sustainable agriculture and the reduced use of chemical fertilizers.


Assuntos
Meristema , Raízes de Plantas , Folhas de Planta , Raízes de Plantas/metabolismo , Brotos de Planta , Plantas
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