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1.
Sci Rep ; 14(1): 10577, 2024 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719920

RESUMO

Cold hypersensitivity in the hands and feet (CHHF) is a protective or predisposing factor for many diseases; however, the relationship between CHHF and erectile dysfunction (ED) remains unclear. We aimed to investigate associations between CHHF and ED among young men of Southeast Asian origin. In this cross-sectional study, sexually active Taiwanese men aged 20-40 years were enrolled via an online questionnaire comprising general demographic information, comorbidities, subjective thermal sensations of their hands and feet in the past 6 months, and their erectile function using the International Index of Erectile Function-5 (IIEF-5). Participants who reported cold sensation of hands and feet were classified to have CHHF; those with IIEF-5 score ≤ 21 were considered to have ED. Total 54.2% and 27.9% of participants had ED and CHHF, respectively. Men with CHHF were significantly younger, had lower body mass index and IIEF-5 scores (p < 0.001), and a lower prevalence of diabetes mellitus (p = 0.033) along with higher prevalence of ED, psychiatric disorders, and insomnia (p < 0.001). After adjusting for predisposing factors of ED, CHHF (odds ratio 1.410, 95% confidence interval 1.159-1.714; p = 0.001) remained an independent predictor of ED. Thus, CHHF is independently associated with ED, affecting more than a quarter of young Taiwanese men. Autonomic dysregulation and subclinical endothelial dysfunction may be common pathophysiologies of CHHF and ED.


Assuntos
Disfunção Erétil , , Mãos , Humanos , Masculino , Disfunção Erétil/epidemiologia , Disfunção Erétil/etiologia , Taiwan/epidemiologia , Adulto , Estudos Transversais , Adulto Jovem , Mãos/fisiopatologia , Pé/fisiopatologia , Síndromes Periódicas Associadas à Criopirina/epidemiologia , Síndromes Periódicas Associadas à Criopirina/complicações , Inquéritos e Questionários , Prevalência , Temperatura Baixa/efeitos adversos , Fatores de Risco
2.
PeerJ ; 12: e17250, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38726376

RESUMO

Herbal infusions exhibit diverse pharmacological effects, such as antioxidant, anti-inflammatory, anticancer, antihypertensive, and antineurodegenerative activities, which can be attributed to the high content of phenolic compounds (e.g., caffeoylquinic acids (CQAs)). In this study, we used ultraperformance liquid chromatography to determine the content of CQAs in the methanolic extracts of model herbs, namely, yerba mate (Ilex paraguariensis), stevia (Stevia rebaudiana), and Indian camphorweed (Pluchea indica (L.) Less.). The results revealed that yerba mate had the highest total CQA content (108.05 ± 1.12 mg/g of dry weight). Furthermore, we evaluated the effect of brewing conditions and storage at 4 °C under dark and light conditions on the antioxidant property and total phenolic and CQA contents of a yerba mate infusion. The analysis of the yerba mate infusions prepared with different steeping times, dried leaf weights, and water temperatures revealed that the amount of extracted CQAs was maximized (∼175 mg/150 mL) when 6 g of dried leaves were steeped in hot water for 10 min. A total of 10-day refrigerated storage resulted in no significant changes in the antioxidant activity and total phenolic and CQA contents of an infusion kept in a brown container (dark). However, the antioxidant properties and total phenolic and CQA contents were negatively affected when kept in a clear container, suggesting the detrimental effect of light exposure. Our study provides practical recommendations for improving the preparation and storage of herbal infusions, thus catering to the needs of consumers, food scientists, and commercial producers. Moreover, it is the first study of the influence of light exposure on the content of crucial quality attributes within plant-based beverages.


Assuntos
Antioxidantes , Ilex paraguariensis , Extratos Vegetais , Ácido Quínico , Stevia , Ilex paraguariensis/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ácido Quínico/análogos & derivados , Ácido Quínico/análise , Stevia/química , Antioxidantes/farmacologia , Antioxidantes/análise , Fenóis/análise , Temperatura Baixa , Folhas de Planta/química , Armazenamento de Medicamentos
3.
Food Res Int ; 186: 114331, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729716

RESUMO

Peach fruit is prone to chilling injury (CI) during low-temperature storage, resulting in quality deterioration and economic losses. Our previous studies have found that exogenous trehalose treatment can alleviate the CI symptoms of peach by increasing sucrose accumulation. The purpose of this study was to explore the potential molecular mechanism of trehalose treatment in alleviating CI in postharvest peach fruit. Transcriptome analysis showed that trehalose induced gene expression in pathways of plant MAPK signaling, calcium signaling, and reactive oxygen species (ROS) signaling. Furthermore, molecular docking analysis indicated that PpCDPK24 may activate the ROS signaling pathway by phosphorylating PpRBOHE. Besides, PpWRKY40 mediates the activation of PpMAPKKK2-induced ROS signaling pathway by interacting with the PpRBOHE promoter. Accordingly, trehalose treatment significantly enhanced the activities of antioxidant-related enzymes such as superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and gluathione reductase (GR), as well as the transcription levels AsA-GSH cycle related gene, which led to the reduction of H2O2 and malondialdehyde (MDA) content in peach during cold storage. In summary, our results suggest that the potential molecular mechanism of trehalose treatment is to enhance antioxidant capacity by activating CDPK-mediated Ca2 + -ROS signaling pathway and WRKY-mediated MAPK-WRKY-ROS signaling pathway, thereby reducing the CI in peach fruit.


Assuntos
Antioxidantes , Temperatura Baixa , Frutas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Prunus persica , Espécies Reativas de Oxigênio , Transdução de Sinais , Trealose , Trealose/farmacologia , Trealose/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Simulação de Acoplamento Molecular , Malondialdeído/metabolismo
4.
Plant Cell Rep ; 43(6): 142, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38744747

RESUMO

KEY MESSAGE: 111 PHD genes were newly identified in rye genome and ScPHD5's role in regulating cold tolerance and flowering time was suggested. Plant homeodomain (PHD)-finger proteins regulate the physical properties of chromatin and control plant development and stress tolerance. Although rye (Secale cereale L.) is a major winter crop, PHD-finger proteins in rye have not been studied. Here, we identified 111 PHD genes in the rye genome that exhibited diverse gene and protein sequence structures. Phylogenetic tree analysis revealed that PHDs were genetically close in monocots and diverged from those in dicots. Duplication and synteny analyses demonstrated that ScPHDs have undergone several duplications during evolution and that high synteny is conserved among the Triticeae species. Tissue-specific and abiotic stress-responsive gene expression analyses indicated that ScPHDs were highly expressed in spikelets and developing seeds and were responsive to cold and drought stress. One of these genes, ScPHD5, was selected for further functional characterization. ScPHD5 was highly expressed in the spike tissues and was localized in the nuclei of rye protoplasts and tobacco leaves. ScPHD5-overexpressing Brachypodium was more tolerant to freezing stress than wild-type (WT), with increased CBF and COR gene expression. Additionally, these transgenic plants displayed an extremely early flowering phenotype that flowered more than two weeks earlier than the WT, and vernalization genes, rather than photoperiod genes, were increased in the WT. RNA-seq analysis revealed that diverse stress response genes, including HSPs, HSFs, LEAs, and MADS-box genes, were also upregulated in transgenic plants. Our study will help elucidate the roles of PHD genes in plant development and abiotic stress tolerance in rye.


Assuntos
Flores , Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas , Secale , Flores/genética , Flores/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Secale/genética , Secale/fisiologia , Temperatura Baixa , Plantas Geneticamente Modificadas/genética , Estresse Fisiológico/genética , Genoma de Planta/genética , Família Multigênica , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Dedos de Zinco PHD/genética
5.
J Agric Food Chem ; 72(19): 10692-10709, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38712500

RESUMO

Abiotic stresses including cold, drought, salt, and iron deficiency severely impair plant development, crop productivity, and geographic distribution. Several bodies of research have shed light on the pleiotropic functions of BASIC HELIX-LOOP-HELIX (bHLH) proteins in plant responses to these abiotic stresses. In this review, we mention the regulatory roles of bHLH TFs in response to stresses such as cold, drought, salt resistance, and iron deficiency, as well as in enhancing grain yield in plants, especially crops. The bHLH proteins bind to E/G-box motifs in the target promoter and interact with various other factors to form a complex regulatory network. Through this network, they cooperatively activate or repress the transcription of downstream genes, thereby regulating various stress responses. Finally, we present some perspectives for future research focusing on the molecular mechanisms that integrate and coordinate these abiotic stresses. Understanding these molecular mechanisms is crucial for the development of stress-tolerant crops.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos , Secas , Regulação da Expressão Gênica de Plantas , Deficiências de Ferro , Proteínas de Plantas , Estresse Fisiológico , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Temperatura Baixa , Produtos Agrícolas/metabolismo , Produtos Agrícolas/genética , Produtos Agrícolas/química , Produtos Agrícolas/crescimento & desenvolvimento
6.
PeerJ ; 12: e17371, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38708338

RESUMO

Background: Platycodon grandiflorus belongs to the genus Platycodon and has many pharmacological effects, such as expectorant, antitussive, and anti-tumor properties. Among transcription factor families peculiar to eukaryotes, the basic leucine zipper (bZIP) family is one of the most important, which exists widely in plants and participates in many biological processes, such as plant growth, development, and stress responses. However, genomic analysis of the bZIP gene family and related stress response genes has not yet been reported in P. grandiflorus. Methods: P. grandiflorus bZIP (PgbZIP) genes were first identified here, and the phylogenetic relationships and conserved motifs in the PgbZIPs were also performed. Meanwhile, gene structures, conserved domains, and the possible protein subcellular localizations of these PgbZIPs were characterized. Most importantly, the cis-regulatory elements and expression patterns of selected genes exposed to two different stresses were analyzed to provide further information on PgbZIPs potential biological roles in P. grandiflorus upon exposure to environmental stresses. Conclusions: Forty-six PgbZIPs were identified in P. grandiflorus and divided into nine groups, as displayed in the phylogenetic tree. The results of the chromosomal location and the collinearity analysis showed that forty-six PgbZIP genes were distributed on eight chromosomes, with one tandem duplication event and eleven segmental duplication events identified. Most PgbZIPs in the same phylogenetic group have similar conserved motifs, domains, and gene structures. There are cis-regulatory elements related to the methyl jasmonate (MeJA) response, low-temperature response, abscisic acid response, auxin response, and gibberellin response. Ten PgbZIP genes were selected to study their expression patterns upon exposure to low-temperature and MeJA treatments, and all ten genes responded to these stresses. The real-time quantitative polymerase chain reaction (RT-qPCR) results suggest that the expression levels of most PgbZIPs decreased significantly within 6 h and then gradually increased to normal or above normal levels over the 90 h following MeJA treatment. The expression levels of all PgbZIPs were significantly reduced after 3 h of the low-temperature treatment. These results reveal the characteristics of the PgbZIP family genes and provide valuable information for improving P. grandiflorus's ability to cope with environmental stresses during growth and development.


Assuntos
Acetatos , Fatores de Transcrição de Zíper de Leucina Básica , Ciclopentanos , Regulação da Expressão Gênica de Plantas , Oxilipinas , Filogenia , Platycodon , Oxilipinas/farmacologia , Ciclopentanos/farmacologia , Acetatos/farmacologia , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Platycodon/genética , Platycodon/metabolismo , Estresse Fisiológico/genética , Estresse Fisiológico/efeitos dos fármacos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Temperatura Baixa , Reguladores de Crescimento de Plantas/farmacologia
7.
Sci Rep ; 14(1): 10248, 2024 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-38702372

RESUMO

Ambient air temperature is a key factor affecting human health. Female reproductive disorders are representative health risk events under low temperature. However, the mechanism involving in cold-induced female reproductive disorders remains largely unknown. Female mice were intermittently exposed to cold conditions (4 °C) to address the health risk of low temperature on female reproductive system. Primary granulosa cells (GCs) were prepared and cultured under low temperature (35 °C) or exposed to ß3-adrenoreceptor agonist, isoproterenol, to mimic the condition of cold exposure. Western-blot, RT-PCR, co-IP, ELISA, pharmacological inhibition or siRNA-mediated knockdown of target gene were performed to investigate the possible role of hormones, gap conjunction proteins, and ER stress sensor protein in regulating female reproductive disorders under cold exposure. Cold exposure induced estrous cycle disorder and follicular dysplasia in female mice, accompanying with abnormal upregulation of progesterone and its synthetic rate-limiting enzyme, StAR, in the ovarian granulosa cells. Under the same conditions, an increase in connexin 43 (CX43) expressions in the GCs was also observed, which contributed to elevated progesterone levels in the ovary. Moreover, ER stress sensor protein, PERK, was activated in the ovarian GCs after cold exposure, leading to the upregulation of downstream NRF2-dependent CX43 transcription and aberrant increase in progesterone synthesis. Most importantly, blocking PERK expression in vivo significantly inhibited NRF2/CX43/StAR/progesterone pathway activation in the ovary and efficiently rescued the prolongation of estrous cycle and the increase in follicular atresia of the female mice induced by cold stress. We have elucidated the mechanism of ovarian PERK/NRF2/CX43/StAR/progesterone pathway activation in mediating female reproductive disorder under cold exposure. Targeting PERK might be helpful for maintaining female reproductive health under cold conditions.


Assuntos
Temperatura Baixa , Conexina 43 , Células da Granulosa , Fator 2 Relacionado a NF-E2 , Progesterona , Transdução de Sinais , eIF-2 Quinase , Animais , Feminino , eIF-2 Quinase/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Camundongos , Progesterona/metabolismo , Células da Granulosa/metabolismo , Conexina 43/metabolismo , Conexina 43/genética , Temperatura Baixa/efeitos adversos , Ovário/metabolismo , Ciclo Estral
8.
Sci Rep ; 14(1): 9997, 2024 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693271

RESUMO

This study aims to investigate the effects of intraoral cold water spray on thirst, frequency of oral care and postoperative period pain at surgical incision site in patients having abdominal surgery. The study was carried out as a randomized controlled trial, registered under Clinical Trial Number: NCT05940818. The study involved 110 participants, divided equally into two groups (n = 55): the experimental group and the control group. Data were collected using patient information form, NRS, Intensive Care Oral Care Frequency Assessment Scale (ICOCFAS) and Visual Analog Scale (VAS). The severity of thirst at 1st, 8th, 16th h of post-operative period (p < 0.01) and the frequency of oral care application at 16th h were statistically significantly decreased in the experimental group when compared to the control group (p < 0.01).There wasn't statistically significant difference between the patients in the experimental and control groups in terms of pain at surgical incision site (p > 0.05). The patient's thirst and need for frequent oral care in the postoperative period were reduced by the application of a cold water spray. In patients undergoing abdominal surgery, the use of cold water spray application may be recommended to reduce thirst and the need for frequency of oral care application.


Assuntos
Unidades de Terapia Intensiva , Dor Pós-Operatória , Sede , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/tratamento farmacológico , Adulto , Idoso , Higiene Bucal/métodos , Temperatura Baixa , Medição da Dor , Cuidados Críticos/métodos
9.
Plant Physiol Biochem ; 210: 108621, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38604012

RESUMO

To enhance the postharvest quality of avocado (Persea americana Mill.) fruit, this study investigates alterations in cell wall metabolism and reactive oxygen species (ROS) metabolism during near-freezing temperature (NFT) storage, and explores their impact on fruit softening. The fruit was stored at 25 °C, 5 °C, 2 °C, and NFT, respectively. NFT storage retarded firmness loss and chilling injury in comparison with 25 °C, 5 °C, and 2 °C. NFT storage delayed the decrease of ionic-soluble pectin (ISP) and cellulose (CLL) contents by suppressing cell wall degradation enzyme activities. Correlation analysis showed that cell wall degradation enzyme activities were positively correlated to rates of ethylene release and respiration. Moreover, NFT storage maintained higher levels of DPPH and ABTS scavenging abilities, activities of superoxide dismutase, peroxidase, and catalase, as well as ascorbate-glutathione cycle (ascorbic acid, glutathione, glutathione disulfide, ascorbate peroxidase, cycle-related enzymes), thereby inhibited the increase of ROS content, malondialdehyde content, and cell membrane permeability. Fruit firmness and chilling injury were correlated with the contents of hydrogen (H2O2), superoxide anion (O2.-), ISP, and CLL. These results suggested that NFT could suppress fruit softening and chilling injury by inhibiting cell wall degradation through delaying respiration and ethylene production and suppressing ROS production via activation of antioxidant systems, thereby maintaining quality and prolonged storage life during avocado fruit storage.


Assuntos
Parede Celular , Frutas , Persea , Espécies Reativas de Oxigênio , Persea/metabolismo , Parede Celular/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Frutas/metabolismo , Armazenamento de Alimentos/métodos , Temperatura Baixa , Congelamento , Etilenos/metabolismo , Pectinas/metabolismo , Celulose/metabolismo
10.
Plant Physiol Biochem ; 210: 108576, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38608502

RESUMO

Low temperature severely affects the geographical distribution and production of potato, which may incur cold damage in early spring or winter. Cultivated potatoes, mainly derived from Solanum tuberosum, are sensitive to freezing stress, but wild species of potato such as S. commersonii exhibit both constitutive freezing tolerance and/or cold acclimation tolerance. Hence, such wild species could assist in cold hardiness breeding. Yet the key transcription factors and their downstream functional genes that confer freezing tolerance are far from clear, hindering the breeding process. Here, we used ATAC-seq (Assay for Transposase-Accessible Chromatin with high-throughput sequencing) alongside RNA-seq to investigate the variation in chromatin accessibility and patterns of gene expression in freezing-tolerant CMM5 (S. commersonii), before and after its cold treatment. Our results suggest that after exposure to cold, transcription factors including Dof3, ABF2, PIF4, and MYB4 were predicted to further control the genes active in the synthetic/metabolic pathways of plant hormones, namely abscisic acid, polyamine, and reductive glutathione (among others). This suggests these transcription factors could regulate freezing tolerance of CMM5 leaves. In particular, ScDof3 was proven to regulate the expression of ScproC (pyrroline-5-carboxylate reductase, P5CR) according to dual-LUC assays. Overexpressing ScDof3 in Nicotiana benthamiana leaves led to an increase in both the proline content and expression level of NbproC (homolog of ScproC). These results demonstrate the ScDof3-ScproC module regulates the proline content and thus promotes freezing tolerance in potato. Our research provides valuable genetic resources to further study the molecular mechanisms underpinning cold tolerance in potato.


Assuntos
Aclimatação , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Solanum tuberosum , Solanum tuberosum/genética , Solanum tuberosum/metabolismo , Solanum tuberosum/fisiologia , Aclimatação/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transcriptoma/genética , Temperatura Baixa , Congelamento , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
11.
Physiol Plant ; 176(2): e14272, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38566275

RESUMO

The Dehydration-Responsive Element Binding (DREB) subfamily of transcription factors plays crucial roles in plant abiotic stress response. Ammopiptanthus nanus (A. nanus) is an eremophyte exhibiting remarkable tolerance to environmental stress and DREB proteins may contribute to its tolerance to water deficit and low-temperature stress. In the present study, an A. nanus DREB A5 group transcription factor gene, AnDREB5.1, was isolated and characterized in terms of structure and function in abiotic stress tolerance. AnDREB5.1 protein is distributed in the nucleus, possesses transactivation capacity, and is capable of binding to DRE core cis-acting element. The transcription of AnDREB5.1 was induced under osmotic and cold stress. Tobacco seedlings overexpressing AnDREB5.1 displayed higher tolerance to cold stress, osmotic stress, and oxidative stress compared to wild-type tobacco (WT). Under osmotic and cold stress, overexpression of AnDREB5.1 increased antioxidant enzyme activity in tobacco leaves, inhibiting excessive elevation of ROS levels. Transcriptome sequencing analysis showed that overexpression of AnDREB5.1 raised the tolerance of transgenic tobacco seedlings to abiotic stress by regulating multiple genes, including antioxidant enzymes, transcription factors, and stress-tolerant related functional genes like NtCOR413 and NtLEA14. This study provides new evidence for understanding the potential roles of the DREB A5 subgroup members in plants.


Assuntos
Resposta ao Choque Frio , Fabaceae , Resposta ao Choque Frio/genética , Antioxidantes , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Fabaceae/genética , Estresse Fisiológico/genética , Plântula/genética , Plântula/metabolismo , Nicotiana/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Temperatura Baixa
12.
Food Res Int ; 184: 114265, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38609243

RESUMO

Radio frequency explosion puffing (RFEP) is a novel oil-free puffing technique used to produce crispy textured and nutritious puffed snacks. This study aimed to investigate the effects of freezing at different temperatures (-20 °C, -40 °C, -80 °C) for14 h and freezing times (1 and 2 times) on the cellular structure of purple sweet potato and the quality of RFEP chips. The analysis of cell microstructure, conductivity, and rheology revealed that higher freezing temperatures and more freezing times resulted in increased damage to the cellular structure, leading to greater cell membrane permeability and decreased cell wall stiffness. However, excessive damage to cellular structure caused tissue structure to collapse. Compared with the control group (4 °C), the RFEP sample pre-frozen once at -40 °C had a 47.13 % increase in puffing ratio and a 61.93 % increase in crispness, while hardness decreased by 23.44 % (p < 0.05). There was no significant change in anthocyanin retention or color difference. X-ray microtomography demonstrated that the RFEP sample pre-frozen once at -40 °C exhibited a more homogeneous morphology and uniform pore distribution, resulting in the highest overall acceptability. In conclusion, freezing pre-treatment before RFEP can significantly enhance the puffing quality, making this an effective method for preparing oil-free puffing products for fruits and vegetables.


Assuntos
Ipomoea batatas , Congelamento , Explosões , Parede Celular , Temperatura Baixa
13.
Sensors (Basel) ; 24(7)2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38610278

RESUMO

Transient terahertz time-domain spectroscopy (THz-TDS) imaging has emerged as a novel non-ionizing and noninvasive biomedical imaging modality, designed for the detection and characterization of a variety of tissue malignancies due to their high signal-to-noise ratio and submillimeter resolution. We report our design of a pair of aspheric focusing lenses using a commercially available lens-design software that resulted in about 200 × 200-µm2 focal spot size corresponding to the 1-THz frequency. The lenses are made of high-density polyethylene (HDPE) obtained using a lathe fabrication and are integrated into a THz-TDS system that includes low-temperature GaAs photoconductive antennae as both a THz emitter and detector. The system is used to generate high-resolution, two-dimensional (2D) images of formalin-fixed, paraffin-embedded murine pancreas tissue blocks. The performance of these focusing lenses is compared to the older system based on a pair of short-focal-length, hemispherical polytetrafluoroethylene (TeflonTM) lenses and is characterized using THz-domain measurements, resulting in 2D maps of the tissue refractive index and absorption coefficient as imaging markers. For a quantitative evaluation of the lens effect on the image resolution, we formulated a lateral resolution parameter, R2080, defined as the distance required for a 20-80% transition of the imaging marker from the bare paraffin region to the tissue region in the same image frame. The R2080 parameter clearly demonstrates the advantage of the HDPE lenses over TeflonTM lenses. The lens-design approach presented here can be successfully implemented in other THz-TDS setups with known THz emitter and detector specifications.


Assuntos
Lentes , Imagem Terahertz , Animais , Camundongos , Polietileno , Politetrafluoretileno , Temperatura Baixa
14.
Trends Ecol Evol ; 39(5): 424-426, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38521739

RESUMO

Cold temperatures have been posited as a key driver of polyploidy (possession of multiple chromosome sets). However, high temperatures associated with fire, and the indirect impact of post-fire environments in polypoid formation and establishment deserve more attention for a comprehensive understanding of polyploid ecology, evolution, and current distributions.


Assuntos
Incêndios , Poliploidia , Evolução Biológica , Temperatura Baixa
15.
Int J Biol Macromol ; 266(Pt 1): 131020, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38521330

RESUMO

Ammopiptanthus mongolicus, a rare temperate evergreen broadleaf shrub, exhibits remarkable tolerance to low temperature and drought stress in winter. Late embryogenesis abundant (LEA) proteins, a kind of hydrophilic protein with a protective function, play significant roles in enhancing plant tolerance to abiotic stress. In this present study, we analyzed the evolution and expression of LEA genes in A. mongolicus, and investigated the function and regulatory mechanism of dehydrin under abiotic stresses. Evolutionary analysis revealed that 14 AmLEA genes underwent tandem duplication events, and 36 AmLEA genes underwent segmental duplication events Notably, an expansion in SKn-type dehydrins was observed. Expression analysis showed that AmDHN4, a SKn-type dehydrin, was up-regulated in winter and under low temperature and osmotic stresses. Functional analysis showcased that the heterologous expression of the AmDHN4 enhanced the tolerance of yeast and tobacco to low temperature stress. Additionally, the overexpression of AmDHN4 significantly improved the tolerance of transgenic Arabidopsis to low temperature, drought, and osmotic stress. Further investigations identified AmWRKY45, a downstream transcription factor in the jasmonic acid signaling pathway, binding to the AmDHN4 promoter and positively regulating its expression. In summary, these findings contribute to a deeper understanding of the functional and regulatory mechanisms of dehydrin.


Assuntos
Arabidopsis , Temperatura Baixa , Regulação da Expressão Gênica de Plantas , Pressão Osmótica , Proteínas de Plantas , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Estresse Fisiológico/genética , Filogenia , Secas , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Estações do Ano
16.
Plant Physiol Biochem ; 208: 108473, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38430784

RESUMO

Alternative splicing (AS) was an important post-transcriptional mechanism that involved in plant resistance to adversity stress. WRKY transcription factors function as transcriptional activators or repressors to modulate plant growth, development and stress response. However, the role of alternate splicing of WRKY in cold tolerance is poorly understood in tea plants. In this study, we found that the CsWRKY21 transcription factor, a member of the WRKY IId subfamily, was induced by low temperature. Subcellular localization and transcriptional activity assays showed that CsWRKY21 localized to the nucleus and had no transcriptional activation activity. Y1H and dual-luciferase reporter assays showed that CsWRKY21 suppressed expression of CsABA8H and CsUGT by binding with their promoters. Transient overexpression of CsABA8H and CsUGT reduced abscisic acid (ABA) content in tobacco leaves. Furthermore, we discovered that CsWRKY21 undergoes AS in the 5'UTR region. The AS transcript CsWRKY21-b was induced at low temperature, up to 6 folds compared to the control, while the full-length CsWRKY21-a transcript did not significantly change. Western blot analysis showed that the retention of introns in the 5'UTR region of CsWRKY21-b led to higher CsWRKY21 protein content. These results revealed that alternative splicing of CsWRKY21 involved in cold tolerance of tea plant by regulating the protein expression level and then regulating the content of ABA, and provide insights into molecular mechanisms of low temperature defense mediated by AS in tea plant.


Assuntos
Processamento Alternativo , Proteínas de Plantas , Processamento Alternativo/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiões 5' não Traduzidas , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Temperatura Baixa , Ácido Abscísico/farmacologia , Ácido Abscísico/metabolismo , Chá , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico
17.
Plant Physiol Biochem ; 208: 108464, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38442629

RESUMO

Low temperature-induced cold stress is a major threat to plant growth, development and distribution. Unraveling the responses of temperature-sensitive crops to cold stress and the mechanisms of cold acclimation are critical for food demand. In this study, combined physiological, transcriptomic, and metabolomic analyses were conducted on Nicotiana tabacum suffering short-term 4 °C cold stress. Our results showed that cold stress destroyed cellular membrane stability, decreased the chlorophyll (Chl) and carotenoid contents, and closed stomata, resulting in lipid peroxidation and photosynthesis restriction. Chl fluorescence measurements revealed that primary photochemistry, photoelectrochemical quenching and photosynthetic electron transport in Nicotiana tabacum leaves were seriously suppressed upon exposer to cold stress. Enzymatic and nonenzymatic antioxidants, including superoxide dismutase, catalase, peroxidase, reduced glutathione, proline, and soluble sugar, were all profoundly increased to trigger the cold acclimation defense against oxidative damage. A total of 178 metabolites and 16,204 genes were differentially expressed in cold-stressed Nicotiana tabacum leaves. MEturquoise and MEblue modules identified by WGCNA were highly correlated with physiological indices, and the corresponding hub genes were significantly enriched in pathways related to photosynthesis - antenna proteins and flavonoid biosynthesis. Untargeted metabolomic analysis identified specific metabolites, including sucrose, phenylalanine, glutamine, glutamate, and proline, that enhance plant cold acclimation. Combined transcriptomics and metabolomic analysis highlight the vital roles of carbohydrate and amino acid metabolism in enhancing the cold tolerance of Nicotiana tabacum. Our comprehensive investigation provides novel insights for efforts to alleviate low temperature-induced oxidative damage to Nicotiana tabacum plants and proposes a breeding target for cold stress-tolerant cultivars.


Assuntos
Resposta ao Choque Frio , Nicotiana , Resposta ao Choque Frio/genética , Nicotiana/genética , Perfilação da Expressão Gênica , Fotossíntese/fisiologia , Metabolômica , Prolina/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Temperatura Baixa
18.
Am J Physiol Endocrinol Metab ; 326(5): E588-E601, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38477875

RESUMO

In rodents, loss of estradiol (E2) reduces brown adipose tissue (BAT) metabolic activity. Whether E2 impacts BAT activity in women is not known. BAT oxidative metabolism was measured in premenopausal (n = 27; 35 ± 9 yr; body mass index = 26.0 ± 5.3 kg/m2) and postmenopausal (n = 25; 51 ± 8 yr; body mass index = 28.0 ± 5.0 kg/m2) women at room temperature and during acute cold exposure using [11C]acetate with positron emission tomography coupled with computed tomograph. BAT glucose uptake was also measured during acute cold exposure using 2-deoxy-2-[18F]fluoro-d-glucose. To isolate the effects of ovarian hormones from biological aging, measurements were repeated in a subset of premenopausal women (n = 8; 40 ± 4 yr; BMI = 28.0 ± 7.2 kg/m2) after 6 mo of gonadotropin-releasing hormone agonist therapy to suppress ovarian hormones. At room temperature, there was no difference in BAT oxidative metabolism between premenopausal (0.56 ± 0.31 min-1) and postmenopausal women (0.63 ± 0.28 min-1). During cold exposure, BAT oxidative metabolism (1.28 ± 0.85 vs. 0.91 ± 0.63 min-1, P = 0.03) and net BAT glucose uptake (84.4 ± 82.5 vs. 29.7 ± 31.4 nmol·g-1·min-1, P < 0.01) were higher in premenopausal than postmenopausal women. In premenopausal women who underwent gonadotropin-releasing hormone agonist, cold-stimulated BAT oxidative metabolism was reduced to a similar level (from 1.36 ± 0.66 min-1 to 0.91 ± 0.41 min-1) to that observed in postmenopausal women (0.91 ± 0.63 min-1). These results provide the first evidence in humans that reproductive hormones are associated with BAT oxidative metabolism and suggest that BAT may be a target to attenuate age-related reduction in energy expenditure and maintain metabolic health in postmenopausal women.NEW & NOTEWORTHY In rodents, loss of estrogen reduces brown adipose tissue (BAT) activity. Whether this is true in humans is not known. We found that BAT oxidative metabolism and glucose uptake were lower in postmenopausal compared to premenopausal women. In premenopausal women who underwent ovarian suppression to reduce circulating estrogen, BAT oxidative metabolism was reduced to postmenopausal levels. Thus the loss of ovarian function in women leads to a reduction in BAT metabolic activity independent of age.


Assuntos
Tecido Adiposo Marrom , Fluordesoxiglucose F18 , Humanos , Feminino , Tecido Adiposo Marrom/metabolismo , Fluordesoxiglucose F18/metabolismo , Metabolismo Energético , Glucose/metabolismo , Tomografia por Emissão de Pósitrons , Estrogênios/farmacologia , Hormônio Liberador de Gonadotropina/metabolismo , Temperatura Baixa , Termogênese
19.
Hum Cell ; 37(3): 593-606, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38538930

RESUMO

Environmental temperature and cellular mechanical force are the inherent factors that participate in various biological processes and regulate cancer progress, which have been hot topics worldwide. They occupy a dominant part in the cancer tissues through different approaches. However, extensive investigation regarding pathological mechanisms in the carcinogenic field. After research, we found cold stress via two means to manipulate tumors: neuroscience and mechanically sensitive ion channels (MICHs) such as TRP families to regulate the physiological and pathological activities. Excessive cold stimulation mediated neuroscience acting on every cancer stage through the hypothalamus-pituitary-adrenocorticoid (HPA) to reach the target organs. Comparatively speaking, mechanical force via Piezo of MICHs controls cancer development. The progression of cancer depends on the internal activation of proto-oncogenes and the external tumorigenic factors; the above two means eventually lead to genetic disorders at the molecular level. This review summarizes the interaction of bidirectional communication between them and the tumor. It covers the main processes from cytoplasm to nucleus related to metastasis cascade and tumor immune escape.


Assuntos
Neoplasias , Humanos , Estresse Mecânico , Neoplasias/genética , Neoplasias/patologia , Carcinogênese , Canais Iônicos/genética , Temperatura Baixa
20.
Cell Rep ; 43(4): 113978, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38522069

RESUMO

Transcription factor MAFB regulates various homeostatic functions of macrophages. This study explores the role of MAFB in brown adipose tissue (BAT) thermogenesis using macrophage-specific Mafb-deficient (Mafbf/f::LysM-Cre) mice. We find that Mafb deficiency in macrophages reduces thermogenesis, energy expenditure, and sympathetic neuron (SN) density in BAT under cold conditions. This phenotype features a proinflammatory environment that is characterized by macrophage/granulocyte accumulation, increases in interleukin-6 (IL-6) production, and IL-6 trans-signaling, which lead to decreases in nerve growth factor (NGF) expression and reduction in SN density in BAT. We confirm MAFB regulation of IL-6 expression using luciferase readout driven by IL-6 promoter in RAW-264.7 macrophage cell lines. Immunohistochemistry shows clustered organization of NGF-producing cells in BAT, which are primarily TRPV1+ vascular smooth muscle cells, as additionally shown using single-cell RNA sequencing and RT-qPCR of the stromal vascular fraction. Treating Mafbf/f::LysM-Cre mice with anti-IL-6 receptor antibody rescues SN density, body temperature, and energy expenditure.


Assuntos
Tecido Adiposo Marrom , Temperatura Baixa , Interleucina-6 , Macrófagos , Fator de Transcrição MafB , Neurônios , Termogênese , Animais , Fator de Transcrição MafB/metabolismo , Fator de Transcrição MafB/genética , Tecido Adiposo Marrom/metabolismo , Camundongos , Macrófagos/metabolismo , Neurônios/metabolismo , Interleucina-6/metabolismo , Células RAW 264.7 , Fator de Crescimento Neural/metabolismo , Metabolismo Energético , Masculino , Camundongos Endogâmicos C57BL
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