Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Sci Total Environ ; 949: 175172, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39094664

RESUMO

Crop yields are affected by hydroclimatic and edaphic conditions, but their interacting roles are often neglected when assessing crop yields at the regional scale. Moreover, often used hydroclimatic conditions such as precipitation and temperature are not as physiologically linked to primary production and yields as actual evapotranspiration. Using statistical models, we quantified the combined effects of edaphic and hydroclimatic conditions on county yields of irrigated rice and rainfed corn, soybean, and spring and winter wheat in the USA (2000-2019). Precipitation and temperature, or actual evapotranspiration, aggregated during the growing season or before and after flowering/silk emergence, in interaction with soil sand content or bulk density, explained up to 87 % of the yield variability. However, actual evapotranspiration explained yields better than precipitation and temperature and their interactions for most combinations of crops and growth periods. At high actual evapotranspiration, yield plateaued or, for spring wheat, decreased. Yields were generally most sensitive to changes in hydroclimatic conditions during part of rather than the entire growing season, and most often after flowering. Soil texture and bulk density modulated the impacts of hydroclimatic conditions: corn and soybean yields were higher in finer soils compared with sandy soils under high evapotranspiration, but lower at low evapotranspiration. Additionally, the yield-maximizing precipitation decreased with sand content and increased with bulk density for most crops. Increasingly available actual evapotranspiration estimates, combined with soil properties, offer an alternative, and more physiologically-based, yield predictor over large climatic gradients to the more widely used precipitation and temperature.


Assuntos
Produtos Agrícolas , Chuva , Solo , Solo/química , Produtos Agrícolas/crescimento & desenvolvimento , Estados Unidos , Transpiração Vegetal , Agricultura/métodos , Estações do Ano , Zea mays/crescimento & desenvolvimento , Triticum/crescimento & desenvolvimento
2.
Ann Med Surg (Lond) ; 85(7): 3630-3633, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37427163

RESUMO

Intussusception is a common finding among children. Conversely, it is infrequent in adults. Colonic lipomas are generally clinically silent making them a very rare aetiology of intussusception. Presentation of case: The authors present a case of a 48-year-old male who presented to the emergency department suffering from severe abdominal pain. Following examination and investigations, a giant lipoma (GL) in the transverse colon was identified via ultrasound which showed the classical "target sign" Intussusception among adults is unusual as it accounts for only 1% of bowel obstruction cases. Being colo-colonic makes it even more unlikely since it occurs only in 17% of intestinal obstruction cases. GLs exceeding 5 cm in size can present with a variety of symptoms. Intussusception is an uncommon presentation of a GL. Preoperative diagnosis of GL-induced intussusception is highly improbable and surgical resection is the treatment of choice. Conclusion: Despite the dominance of the asymptomatic presentation of lipomas, considering its diagnosis in the case of an intussusception-induced acute abdomen should cross physicians' minds.

3.
Artigo em Inglês | MEDLINE | ID: mdl-35247568

RESUMO

Inositol plays a significant role in cellular function and signaling. Studies in yeast have demonstrated an "inositol-less death" phenotype, suggesting that inositol is an essential metabolite. In yeast, inositol synthesis is highly regulated, and inositol levels have been shown to be a major metabolic regulator, with its abundance affecting the expression of hundreds of genes. Abnormalities in inositol metabolism have been associated with several human disorders. Despite its importance, very little is known about the regulation of inositol synthesis and the pathways regulated by inositol in human cells. The current study aimed to address this knowledge gap. Knockout of ISYNA1 (encoding myo-inositol-3-P synthase 1) in HEK293T cells generated a human cell line that is deficient in de novo inositol synthesis. ISYNA1-KO cells exhibited inositol-less death when deprived of inositol. Lipidomic analysis identified inositol deprivation as a global regulator of phospholipid levels in human cells, including downregulation of phosphatidylinositol (PI) and upregulation of the phosphatidylglycerol (PG)/cardiolipin (CL) branch of phospholipid metabolism. RNA-Seq analysis revealed that inositol deprivation induced substantial changes in the expression of genes involved in cell signaling, including extracellular signal-regulated kinase (ERK), and genes controlling amino acid transport and protein processing in the endoplasmic reticulum (ER). This study provides the first in-depth characterization of the effects of inositol deprivation on phospholipid metabolism and gene expression in human cells, establishing an essential role for inositol in maintaining cell viability and regulating cell signaling and metabolism.


Assuntos
Inositol , Saccharomyces cerevisiae , Células HEK293 , Humanos , Inositol/metabolismo , Fosfatidilinositóis/metabolismo , Saccharomyces cerevisiae/metabolismo , Transdução de Sinais
4.
Front Cell Neurosci ; 15: 735622, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34531727

RESUMO

Bipolar disorder (BD) is a mood disorder that affects millions worldwide and is associated with severe mood swings between mania and depression. The mood stabilizers valproate (VPA) and lithium (Li) are among the main drugs that are used to treat BD patients. However, these drugs are not effective for all patients and cause serious side effects. Therefore, better drugs are needed to treat BD patients. The main barrier to developing new drugs is the lack of knowledge about the therapeutic mechanism of currently available drugs. Several hypotheses have been proposed for the mechanism of action of mood stabilizers. However, it is still not known how they act to alleviate both mania and depression. The pathology of BD is characterized by mitochondrial dysfunction, oxidative stress, and abnormalities in calcium signaling. A deficiency in the unfolded protein response (UPR) pathway may be a shared mechanism that leads to these cellular dysfunctions. This is supported by reported abnormalities in the UPR pathway in lymphoblasts from BD patients. Additionally, studies have demonstrated that mood stabilizers alter the expression of several UPR target genes in mouse and human neuronal cells. In this review, we outline a new perspective wherein mood stabilizers exert their therapeutic mechanism by activating the UPR. Furthermore, we discuss UPR abnormalities in BD patients and suggest future research directions to resolve discrepancies in the literature.

5.
J Microbiol Methods ; 189: 106300, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34389363

RESUMO

Myo-inositol is a six­carbon sugar that is essential for the growth of mammalian cells and must be obtained through either extracellular uptake or de novo biosynthesis. The physiological importance of myo-inositol stems from its incorporation into phosphoinositides and inositol phosphates, which serve a variety of signaling, regulatory, and structural roles in cells. To study myo-inositol metabolism and function, it is essential to have a reliable method for assaying myo-inositol levels. However, current approaches to assay myo-inositol levels are time-consuming, expensive, and often unreliable. This article describes a simple new myo-inositol bioassay that utilizes an auxotrophic strain of S. cerevisiae to measure myo-inositol concentration in solutions. The accuracy of this method was confirmed by comparing assay values to those obtained by tandem mass spectrometry (LC-MS/MS). It is easy to perform, inexpensive, does not require sophisticated equipment, and is specific for myo-inositol.


Assuntos
Bioensaio/métodos , Fosfatos de Inositol/análise , Fosfatos de Inositol/metabolismo , Saccharomyces cerevisiae/metabolismo , Bioensaio/economia , Transporte Biológico , Cromatografia Líquida , Espectrometria de Massas em Tandem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA