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1.
Pestic Biochem Physiol ; 200: 105845, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38582577

RESUMO

7-dehydrocholesterol (7-DHC) is a key intermediate product used for biosynthesis of molting hormone. This is achieved through a series of hydroxylation reactions catalyzed by the Halloween family of cytochrome P450s. Neverland is an enzyme catalyzes the first reaction of the ecdysteroidogenic pathway, which converts dietary cholesterol into 7-DHC. However, research on the physiological function of neverland in orthopteran insects is lacking. In this study, neverland from Locusta migratoria (LmNvd) was cloned and analyzed. LmNvd was mainly expressed in the prothoracic gland and highly expressed on days 6 and 7 of fifth instar nymphs. RNAi-mediated silencing of LmNvd resulted in serious molting delays and abnormal phenotypes, which could be rescued by 7-DHC and 20-hydroxyecdysone supplementation. Hematoxylin and eosin staining results showed that RNAi-mediated silencing of LmNvd disturbed the molting process by both promoting the synthesis of new cuticle and suppressing the degradation of the old cuticle. Quantitative real-time PCR results suggested that the mRNA expression of E75 early gene and chitinase 5 gene decreased and that of chitin synthase 1 gene was markedly upregulated after knockdown of LmNvd. Our results suggest that LmNvd participates in the biosynthesis process of molting hormone, which is involved in regulating chitin synthesis and degradation in molting cycles.


Assuntos
Locusta migratoria , Muda , Animais , Muda/genética , Ecdisona/metabolismo , Locusta migratoria/genética , Locusta migratoria/metabolismo , Interferência de RNA , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo
2.
Front Immunol ; 15: 1444426, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39139571

RESUMO

Breast cancer (BC) is one of the most common and fatal malignancies among women worldwide. Circadian rhythms have emerged in recent studies as being involved in the pathogenesis of breast cancer. In this paper, we reviewed the molecular mechanisms by which the dysregulation of the circadian genes impacts the development of BC, focusing on the critical clock genes, brain and muscle ARNT-like protein 1 (BMAL1) and circadian locomotor output cycles kaput (CLOCK). We discussed how the circadian rhythm disruption (CRD) changes the tumor microenvironment (TME), immune responses, inflammation, and angiogenesis. The CRD compromises immune surveillance and features and activities of immune effectors, including CD8+ T cells and tumor-associated macrophages, that are important in an effective anti-tumor response. Meanwhile, in this review, we discuss bidirectional interactions: age and circadian rhythms, aging further increases the risk of breast cancer through reduced vasoactive intestinal polypeptide (VIP), affecting suprachiasmatic nucleus (SCN) synchronization, reduced ability to repair damaged DNA, and weakened immunity. These complex interplays open new avenues toward targeted therapies by the combination of clock drugs with chronotherapy to potentiate the immune response while reducing tumor progression for better breast cancer outcomes. This review tries to cover the broad area of emerging knowledge on the tumor-immune nexus affected by the circadian rhythm in breast cancer.


Assuntos
Envelhecimento , Neoplasias da Mama , Ritmo Circadiano , Microambiente Tumoral , Humanos , Microambiente Tumoral/imunologia , Neoplasias da Mama/imunologia , Ritmo Circadiano/imunologia , Feminino , Envelhecimento/imunologia , Animais , Proteínas CLOCK/genética , Proteínas CLOCK/metabolismo , Relógios Biológicos
3.
Insect Sci ; 29(1): 51-64, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33634599

RESUMO

Halloween genes are involved in the biosynthesis of the molting hormone, which plays a key role in insect ecdysis, development, metamorphosis, and reproduction. Our previous work identified five Halloween genes from Locusta migratoria, but their functions are currently unknown. In this study, the sequences of these five Halloween genes were analyzed and characterized. LmCYP307a2, LmCYP306a1, LmCYP302a1, and LmCYP315a1 were primarily expressed in the prothoracic glands, while LmCYP314a1 was universally expressed in peripheral tissues, especially in the ovaries and Malpighian tubules. All five Halloween genes were mainly expressed from the 5th to the 7th d in 5th-instar nymphs. RNA interference (RNAi) silencing of LmCYP307a2 resulted in severe molting delays and molting failure, which could be rescued by supplementary 20-hydroxyecdysone. A hematoxylin and eosin staining analysis suggested that the RNAi of LmCYP307a2 inhibited the ecdysis process by inhibiting the apolysis and degradation of the old cuticle, and by promoting the synthesis of a new cuticle. Quantitative reverse transcription polymerase chain reaction results showed that the expressions of LmE74, LmCht5, and LmCht10 were dramatically down-regulated, while that of LmChsI was substantially up-regulated, after knockdown of LmCYP307a2. The results suggest that LmCYP307a2 is related to the molt process via regulation of chitin synthesis and degradation.


Assuntos
Locusta migratoria , Animais , Ecdisterona , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Locusta migratoria/genética , Locusta migratoria/metabolismo , Muda , Interferência de RNA
4.
Sci Total Environ ; 700: 134513, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31689657

RESUMO

Excessive inputs of potentially toxic elements (PTEs) into the surface environment as a consequence of atmospheric deposition, imposes long-term burdens on agricultural ecosystems. Studying the spatial and temporal variation in PTEs in atmospheric deposition and their effects on plant shoot accumulation are important in understanding the sources and contributions of PTEs in soils and agricultural products. Here, the spatial and temporal variations in cadmium (Cd) concentration and atmospheric deposition fluxes were investigated in five rice-producing areas of the urbanized Chang-Zhu-Tan region over two years. Then, the effects of simulated wet precipitation on the uptake of Cd in rice seedlings in hydroponic culture was explored. The results showed substantial spatial variability in Cd concentrations and atmospheric deposition fluxes in this region. The Cd concentration of atmospheric deposition ranged from 0.07 to 114 µg L-1, and the annual Cd fluxes in the industrial area reached 61.0 g ha-1 but all were <10.0 g ha-1 in the rural areas. Rice seedling growth became significantly inhibited with increasing concentrations of Cd. Cadmium content in the shoots and white roots and dithionite-citrate-bicarbonate (DCB) extractable Cd on root surfaces were significantly and positively correlated with the concentration of Cd in the nutrient solution. Shoot Cd concentrations increased significantly (p < 0.05) when the annual Cd precipitation flux was ≥50 g ha-1 compared to the control with no Cd precipitation, and the concentration in the shoot was higher than that in roots of rice cultivar A159, when the annual simulated wet precipitation flux of Cd was 400 g ha-1. Thus, shoot Cd was directly related to the simulated wet precipitation when the flux exceeded 50 g ha-1a-1, indicating that air pollution is an important source factor affecting crop Cd uptake.


Assuntos
Cádmio/metabolismo , Oryza/metabolismo , Chuva , Poluentes do Solo/metabolismo , Atmosfera/química , Cádmio/análise , Poluentes do Solo/análise , Urbanização
5.
Water Res ; 157: 310-320, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30959334

RESUMO

Water sensitive urban design is being promoted in many countries. In Singapore, the Active, Beautiful, Clean (ABC) Waters Programme is a long-term strategic initiative of PUB, Singapore's National Water Agency, to improve the quality of water and urban liveability. While there are some estimates of the bio-physical and ecological benefits of the ABC Waters Programme, information on its social or non-market values is lacking. Using choice experiment datasets this study explores whether people express preferences for ABC Waters features. It also examines whether there is any difference in preferences between respondents living in developments with and without ABC Waters certification, and between respondents living in public and private housing. It is found that respondents living in private housing have substantially higher willingness to pay for ABC Waters features compared to the respondents in public housing. The differences between respondents from certified and non-certified projects were found to be mixed. Such information would be useful to tailor the design of the ABC Waters program. Finally, the potential impact of using a virtual reality tool to present information in a choice experiment towards people's preferences is explored. Application of a virtual reality tool has reduced the proportion of protest voters and increased people's willingness to pay for ABC Waters projects. Thus, this paper contributes to the growing literature on the implications of providing information visually in non-market valuation surveys.


Assuntos
Habitação , Singapura
6.
Behav Brain Res ; 356: 98-106, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29885845

RESUMO

Vascular dementia (VD) is a heterogeneous group of brain disorders in which cognitive impairment is attributed to cerebrovascular pathologies. Autophagy, a self-cannibalization mechanism, has been demonstrated to be involved in VD progression. Molecular hydrogen is known for its powerful anti-oxidative, anti-apoptotic, and anti-inflammatory activities, and it is also involved in autophagy. However, the effects of hydrogen on VD remain unclear. The current study found that hydrogen-rich water (HRW) significantly alleviated spatial learning and memory impairments. Similar to donepezil treatment, HRW also inhibited neuron loss and shrinkage in the hippocampal CA1 region. In addition, we found that HRW significantly increased the Bcl-2/Bax expression ratio and decreased cleaved caspase-3 expression levels in the hippocampus of VD rats. Moreover, electron microscopy revealed that HRW decreased the number of autophagosomes. We also observed that HRW reduced the increased ratio of LC3-II/I and Beclin 1 expression and saliently upregulated p62 expression. Furthermore, FoxO1 (a major mediator of autophagy regulation) and Atg7 levels were apparently decreased in the hippocampus of HRW-treated bilateral common carotid artery occlusion (2VO) rats. Taken together, these data show that molecular hydrogen exerts beneficial effects on cognitive impairment induced by chronic cerebral hypoperfusion. FoxO1-mediated autophagy plays an important role in the neuroprotective effects of hydrogen in a rat model of VD. Furthermore, the present findings highlight that HRW should be further investigated as a new therapeutic strategy for VD treatment in the future.


Assuntos
Demência Vascular/metabolismo , Hidrogênio/farmacologia , Proteínas do Tecido Nervoso/metabolismo , Animais , Apoptose/efeitos dos fármacos , Autofagia/fisiologia , Proteína Beclina-1/metabolismo , Isquemia Encefálica/patologia , Região CA1 Hipocampal/efeitos dos fármacos , Região CA1 Hipocampal/metabolismo , Caspase 3/metabolismo , Disfunção Cognitiva/tratamento farmacológico , Demência Vascular/fisiopatologia , Modelos Animais de Doenças , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hidrogênio/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Proteínas do Tecido Nervoso/fisiologia , Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Sprague-Dawley , Aprendizagem Espacial/efeitos dos fármacos
8.
Chem Commun (Camb) ; 47(44): 12194-6, 2011 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-21966674

RESUMO

With stoichiometric H(2)O(2) as oxidant, dibenzothiophene (DBT) is oxidized to its corresponding sulfone with high efficiency, catalyzed by a sub-valence heteronuclear peroxotungstate, [C(18)H(37)N(CH(3))(3)](4)[H(2)Se(IV)(3)W(6)O(34)], under mild biphase conditions and the catalyst shows remarkable selectivity of catalytic oxidation towards DBT, cinnamyl alcohol and quinoline.

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