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1.
Injury ; 55(8): 111658, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38879923

RESUMO

BACKGROUND: Accidental impact on a player's head by a powerful soccer ball may lead to brain injuries and concussions during games. It is crucial to assess these injuries promptly and accurately on the field. However, it is challenging for referees, coaches, and even players themselves to accurately recognize potential injuries and concussions following such impacts. Therefore, it is necessary to establish a list of minimum ball velocity thresholds that can result in concussions at different impact locations on the head. Additionally, it is important to identify the affected brain regions responsible for impairments in brain function and potential clinical symptoms. METHODS: By using a full human finite element model, dynamic responses and brain injuries caused by unintentional soccer ball impacts on six distinct head locations (forehead, tempus, crown, occiput, face, and jaw) at varying ball velocities (10, 15, 20, 25, 30, 35, 40, and 60 m/s) were simulated and investigated. Intracranial pressure, Von-Mises stress, and first principal strain were analyzed, the ball velocity thresholds resulting in concussions at different impact locations were evaluated, and the damage evolution patterns in the brain tissue were analyzed. RESULTS: The impact on the occiput is most susceptible to induce brain injuries compared to all other impact locations. For a conservative assessment, the risk of concussion is present once the soccer ball reaches 17.2 m/s in a frontal impact, 16.6 m/s in a parietal impact, 14.0 m/s in an occipital impact, 17.8 m/s in a temporal impact, 18.5 m/s in a facial impact or 19.2 m/s in a mandibular impact. The brain exhibits the most significant dynamic responses during the initial 10-20 ms, and the damaged regions are primarily concentrated in the medial temporal lobe and the corpus callosum, potentially causing impairments in brain functions. CONCLUSIONS: This work offers a framework for quantitatively assessing brain injuries and concussions induced by an unintentional soccer ball impact. Determining the ball velocity thresholds at various impact locations provides a benchmark for evaluating the risks of concussion. The examination of brain tissue damage evolution introduces a novel approach to linking biomechanical responses with possible clinical symptoms.

2.
J Sci Food Agric ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38899487

RESUMO

BACKGROUND: Walnut protein (WP) is recognized as a valuable plant protein. However, the poor solubility and functional properties limit its application in the food industry. It is a great requirement to improve the physicochemical properties of WP. RESULTS: Following a 90 min restricted enzymatic hydrolysis period, the solubility of WP significantly increased from 3.24% to 54.54%, with the majority of WP hydrolysates (WPHs) possessing a molecular weight exceeding 50 kDa. Circular dichroism spectra showed that post-hydrolysis, the structure of the protein became more flexible, while the hydrolysis time did not significantly alter the protein's secondary structure. After hydrolysis, WP's surface hydrophobicity significantly increased from 2279 to 6100. Furthermore, WPHs exhibited a strong capacity for icariin loading and micelle formation with critical micelle concentration values of 0.71, 0.99 and 1.09 mg mL-1, respectively. Moreover, similar immuno-enhancement activities were observed in WPHs. After exposure to WPHs, the pinocytosis of RAW264.7 macrophages was significantly improved. WPH treatment also increased the production of nitric oxide, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in macrophages. Up-regulation of mRNA expressions of IL-6, inducible nitric oxide synthase (iNOS) and TNF-α was observed in a dose-dependent manner. CONCLUSION: The enhancement of functionality and bioactivity in WP can be achieved through the application of limited enzyme digestion with trypsin. This process effectively augments the nutritional value and utility of the protein, making it a valuable component in various dietary applications. © 2024 Society of Chemical Industry.

3.
J Nanobiotechnology ; 22(1): 330, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862987

RESUMO

The cryopreservation and transplantation of ovarian tissue underscore its paramount importance in safeguarding reproductive capacity and ameliorating reproductive disorders. However, challenges persist in ovarian tissue cryopreservation and transplantation (OTC-T), including the risk of tissue damage and dysfunction. Consequently, there has been a compelling exploration into the realm of nanoregulators to refine and enhance these procedures. This review embarks on a meticulous examination of the intricate anatomical structure of the ovary and its microenvironment, thereby establishing a robust groundwork for the development of nanomodulators. It systematically categorizes nanoregulators and delves deeply into their functions and mechanisms, meticulously tailored for optimizing ovarian tissue cryopreservation and transplantation. Furthermore, the review imparts valuable insights into the practical applications and obstacles encountered in clinical settings associated with OTC-T. Moreover, the review advocates for the utilization of microbially derived nanomodulators as a potent therapeutic intervention in ovarian tissue cryopreservation. The progression of these approaches holds the promise of seamlessly integrating nanoregulators into OTC-T practices, thereby heralding a new era of expansive applications and auspicious prospects in this pivotal domain.


Assuntos
Criopreservação , Ovário , Criopreservação/métodos , Feminino , Humanos , Animais
4.
J Ethnopharmacol ; 333: 118438, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38848972

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Hyperlipidemia as a major health issue has attracted much public attention. As a geographical indication product of China, Liupao tea (LPT) is a typical representative of traditional Chinese dark tea that has shown good potential in regulating glucose and lipid metabolism. LPT has important medicinal value in hyperlipidemia prevention. However, the active ingredients and metabolic mechanisms by which LPT alleviates hyperlipidemia remain unclear. AIM OF THE STUDY: This study aimed to systematically investigate the metabolic mechanisms and active ingredients of LPT extract in alleviating hyperlipidemia. MATERIALS AND METHODS: Firstly, we developed a mouse model of hyperlipidemia to study the pharmacodynamics of LPT. Subsequently, network pharmacology and molecular docking were performed to predict the potential key active ingredients and core targets of LPT against hyperlipidemia. LC-MS/MS was used to validate the identity of key active ingredients in LPT with chemical standards. Finally, the effect and metabolic mechanisms of LPT extract in alleviating hyperlipidemia were investigated by integrating metabolomic, lipidomic, and gut microbiome analyses. RESULTS: Results showed that LPT extract effectively improved hyperlipidemia by suppressing weight gain, remedying dysregulation of glucose and lipid metabolism, and reducing hepatic damage. Network pharmacology analysis and molecular docking suggested that four potential active ingredients and seven potential core targets were closely associated with roles for hyperlipidemia treatment. Ellagic acid, catechin, and naringenin were considered to be the key active ingredients of LPT alleviating hyperlipidemia. Additionally, LPT extract modulated the mRNA expression levels of Fxr, Cyp7a1, Cyp8b1, and Cyp27a1 associated with bile acid (BA) metabolism, mitigated the disturbances of BA and glycerophospholipid (GP) metabolism in hyperlipidemia mice. Combining fecal microbiota transplantation and correlation analysis, LPT extract effectively improved species diversity and abundance of gut microbiota, particularly the BA and GP metabolism-related gut microbiota, in the hyperlipidemia mice. CONCLUSIONS: LPT extract ameliorated hyperlipidemia by modulating GP and BA metabolism by regulating Lactobacillus and Dubosiella, thereby alleviating hyperlipidemia. Three active ingredients of LPT served as the key factors in exerting an improvement on hyperlipidemia. These findings provide new insights into the active ingredients and metabolic mechanisms of LPT in improving hyperlipidemia, suggesting that LPT can be used to prevent and therapeutic hyperlipidemia.

5.
J Pharm Biomed Anal ; 246: 116213, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38754155

RESUMO

Triterpenoid saponins, a major bioactive component of liquorice, possess high hydrophilicity and often co-occur with other impurities of similar polarity. Additionally, subtle structural differences of some triterpenoid saponins bring challenges to comprehensive characterisation. In this study, triterpenoid saponins of three Glycyrrhiza species were systematically analysed using rapid resolution liquid chromatography quadrupole time-of-flight mass spectrometry (RRLC-Q-TOF-MS) coupled with mass defect filtering (MDF). Firstly, comprehensive date acquisition was achieved using RRLC-Q-TOF-MS. Secondly, a polygonal MDF method was established by summarizing known and speculated substituents and modifications based on the core structure to rapidly screen potential triterpenoid saponins. Thirdly, based on the fragmentation patterns of reference compounds, an identification strategy for characterisation of triterpenoid saponins was proposed. The strategy divided triterpenoid saponins into three distinct classes. By this strategy, 98 triterpenoid saponins including 10 potential new ones were tentatively characterised. Finally, triterpenoid saponins of three Glycyrrhiza species were further analysed using principle component analysis (PCA) and orthogonality partial least squares discriminant analysis (OPLS-DA). Among these, 18 compounds with variable importance in projections (VIP) > 1.0 and P values < 0.05 were selected to distinguish three Glycyrrhiza species. Overall, our study provided a reference for quality control and rational use of the three species.


Assuntos
Glycyrrhiza , Saponinas , Triterpenos , Saponinas/química , Saponinas/análise , Glycyrrhiza/química , Triterpenos/química , Triterpenos/análise , Espectrometria de Massas/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Extratos Vegetais/química
6.
Biochem Pharmacol ; 225: 116250, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38705537

RESUMO

Obesity has emerged as a prominent global health concern, with heat stress posing a significant challenge to both human health and animal well-being. Despite a growing interest in environmental determinants of obesity, very few studies have examined the associations between heat stress-related environmental factors and adiposity. Consequently, there exists a clear need to understand the molecular mechanisms underlying the obesogenic effects of heat stress and to formulate preventive strategies. This study focused on culturing porcine subcutaneous preadipocytes at 41.5 ℃ to induce heat stress, revealing that this stressor triggered apoptosis and fat deposition. Analysis demonstrated an upregulation in the expression of HSP70, BAX, adipogenesis-related genes (PPARγ, AP2, CEBPα and FAS), the p-AMPK/AMPK ratio and SIRT1, PGC-1α in the heat stress group compared to the control group (P < 0.05). Conversely, the expression of lipid lysis-related genes (ATGL, HSL and LPL) and Bcl-2 decreased in the heat stress group compared to the control group (P < 0.05). Furthermore, subsequent activator and/or inhibitor experiments validated that heat stress modulated HSP70 and AMPK signalling pathways to enhance lipogenesis and inhibit lipolysis in porcine subcutaneous preadipocytes. Importantly, this study reveals, for the first time, that EGCG mitigates heat-stress-induced fat deposition by targeting HSP70 through the activation of AMPK-SIRT1-PGC-1α in porcine subcutaneous preadipocytes. These findings elucidate the molecular mechanisms contributing to heat stress-induced obesity and provide a foundation for the potential clinical utilisation of EGCG as a preventive measure against both heat stress and obesity.


Assuntos
Adipócitos , Catequina , Proteínas de Choque Térmico HSP70 , Sirtuína 1 , Animais , Sirtuína 1/metabolismo , Sirtuína 1/genética , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP70/genética , Suínos , Catequina/farmacologia , Catequina/análogos & derivados , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Resposta ao Choque Térmico/efeitos dos fármacos , Resposta ao Choque Térmico/fisiologia , Células Cultivadas , Gordura Subcutânea/metabolismo , Gordura Subcutânea/efeitos dos fármacos
7.
Signal Transduct Target Ther ; 9(1): 129, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740763

RESUMO

The safety and efficacy of COVID-19 vaccines in the elderly, a high-risk group for severe COVID-19 infection, have not been fully understood. To clarify these issues, this prospective study followed up 157 elderly and 73 young participants for 16 months and compared the safety, immunogenicity, and efficacy of two doses of the inactivated vaccine BBIBP-CorV followed by a booster dose of the recombinant protein vaccine ZF2001. The results showed that this vaccination protocol was safe and tolerable in the elderly. After administering two doses of the BBIBP-CorV, the positivity rates and titers of neutralizing and anti-RBD antibodies in the elderly were significantly lower than those in the young individuals. After the ZF2001 booster dose, the antibody-positive rates in the elderly were comparable to those in the young; however, the antibody titers remained lower. Gender, age, and underlying diseases were independently associated with vaccine immunogenicity in elderly individuals. The pseudovirus neutralization assay showed that, compared with those after receiving two doses of BBIBP-CorV priming, some participants obtained immunological protection against BA.5 and BF.7 after receiving the ZF2001 booster. Breakthrough infection symptoms last longer in the infected elderly and pre-infection antibody titers were negatively associated with the severity of post-infection symptoms. The antibody levels in the elderly increased significantly after breakthrough infection but were still lower than those in the young. Our data suggest that multiple booster vaccinations at short intervals to maintain high antibody levels may be an effective strategy for protecting the elderly against COVID-19.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , Vacinas de Produtos Inativados , Humanos , COVID-19/prevenção & controle , COVID-19/imunologia , Feminino , Masculino , Idoso , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/administração & dosagem , SARS-CoV-2/imunologia , Estudos Prospectivos , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Vacinas de Produtos Inativados/imunologia , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de Produtos Inativados/administração & dosagem , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/sangue , Idoso de 80 Anos ou mais , Adulto , Vacinação , Estudos Longitudinais , Pessoa de Meia-Idade , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/efeitos adversos , Vacinas Sintéticas/administração & dosagem , Imunogenicidade da Vacina/imunologia , Imunização Secundária
8.
Adv Sci (Weinh) ; 11(23): e2307819, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38569219

RESUMO

The gut-brain axis has recently emerged as a crucial link in the development and progression of Parkinson's disease (PD). Dysregulation of the gut microbiota has been implicated in the pathogenesis of this disease, sparking growing interest in the quest for non-invasive biomarkers derived from the gut for early PD diagnosis. Herein, an artificial intelligence-guided gut-microenvironment-triggered imaging sensor (Eu-MOF@Au-Aptmer) to achieve non-invasive, accurate screening for various stages of PD is presented. The sensor works by analyzing α-Syn in the gut using deep learning algorithms. By monitoring changes in α-Syn, the sensor can predict the onset of PD with high accuracy. This work has the potential to revolutionize the diagnosis and treatment of PD by allowing for early intervention and personalized treatment plans. Moreover, it exemplifies the promising prospects of integrating artificial intelligence (AI) and advanced sensors in the monitoring and prediction of a broad spectrum of diseases and health conditions.


Assuntos
Inteligência Artificial , Microbioma Gastrointestinal , Doença de Parkinson , Doença de Parkinson/diagnóstico por imagem , Humanos , Biomarcadores/metabolismo , Aprendizado Profundo , Eixo Encéfalo-Intestino , Animais , Técnicas Biossensoriais/métodos
9.
Biology (Basel) ; 13(4)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38666835

RESUMO

This methodological study describes the adaptation of a new method in digital wood anatomy, pixel-contrast densitometry, for angiosperm species. The new method was tested on eight species of shrubs and small trees in Southern Siberia, whose wood structure varies from ring-porous to diffuse-porous, with different spatial organizations of vessels. A two-step transformation of wood cross-section photographs by smoothing and Otsu's classification algorithm was proposed to separate images into cell wall areas and empty spaces within (lumen) and between cells. Good synchronicity between measurements within the ring allowed us to create profiles of wood porosity (proportion of empty spaces) describing the growth ring structure and capturing inter-annual differences between rings. For longer-lived species, 14-32-year series from at least ten specimens were measured. Their analysis revealed that maximum (for all wood types), mean, and minimum porosity (for diffuse-porous wood) in the ring have common external signals, mostly independent of ring width, i.e., they can be used as ecological indicators. Further research directions include a comparison of this method with other approaches in densitometry, clarification of sample processing, and the extraction of ecologically meaningful data from wood structures.

10.
Injury ; 55(6): 111457, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38490847

RESUMO

BACKGROUND: Although the Head Injury Criteria (HIC) has been widely applied to assess head impact injuries, it faces two outstanding problems: 1) HIC is affected strongly by the cut-off frequency when processing acceleration signals. And these cut-off frequencies are experiential and lack unified guidelines; 2) If the head was impacted on a different part, should the corresponding HIC threshold be the same? If these problems are not resolved, it could potentially lead to a critical misinterpretation of the safety assessment. METHODS: Finite element method was used to reconstruct head impacts. The head model includes tissues like skull, brainstem, cerebrospinal fluid, etc. The head model was impacted in the frontal, occipital, parietal or lateral direction with different impact velocities. Acceleration signals of the head model were extracted directly from the skull and the head centroid node. To obtain a robust HIC, the filtering class of acceleration signals were analyzed carefully. Then, the relation between rigid body HIC and the centroid node HIC were studied systematically. RESULTS: When the filtering class of rigid body acceleration and centroid node acceleration reached the cut-off frequency, the corresponding derivative of HIC tended to change smoothly. Using these cut-off frequencies, robust HICs were obtained. The rigid body HIC far exceeded that of centroid node HIC, such as 8, 9, 14 and 31 times exceeded in the frontal, occipital, parietal and lateral impact conditions, respectively. Moreover, approximate linear relations were found between the rigid body HIC and the centroid node HIC in different impact directions, respectively. From these relations, the injury thresholds of rigid body HIC of various directions were given quantitatively. CONCLUSIONS: The rational filtering class like CFC 800 and CFC 700 were given for rigid body HIC and centroid node HIC, respectively. The rigid body HIC had a significant discrepancy from the centroid node HIC. Linear relations between the rigid body HIC and centroid node HIC were found, and their slopes changed with impact directions. From these relations, we can adjust the injury thresholds reasonably if the head receives different impacts. These findings can effectively enhance the applicability of HIC.


Assuntos
Aceleração , Traumatismos Craniocerebrais , Análise de Elementos Finitos , Humanos , Traumatismos Craniocerebrais/fisiopatologia , Fenômenos Biomecânicos , Simulação por Computador , Acidentes de Trânsito
11.
BMC Endocr Disord ; 24(1): 36, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38475734

RESUMO

BACKGROUND: Prior studies reported that elevated asprosin level was associated with obesity in adults and animal models. However, the relationship between asprosin level and children with obeisty remains controversial. The aim of our analysis was to systematically review available literatures linking asprosin and children with obesity for a comprehensive understanding of the relationship between circulating asprosin level and obesity in children. METHODS: Eight databases were gleaned for studies published up to January 2024. Standard mean difference with 95% confidence interval (CI) and Fisher's Z transformation was calculated to evaluate the relationship between asprosin level and children with obesity using the Review Manager 5.4 Software. Other indicators were measured via mean difference with 95% CI. RESULTS: Six observational studies were included both in systematic review and meta-analysis. The current evidence indicated that no significant difference was observed in the level of circulating asprosin between the children with and without obesity (SMD = 0.37; 95% CI:-0.22-0.95, p = 0.22). However, Fisher's Z transformation suggested the positive association of circulating asprosin levels and clinical index measuring the degree of obesity: total cholesterol (Fisher's Z: 0.11, 95% CI: 0.02-0.20, p = 0.02). CONCLUSIONS: Circulating asprosin level was not independently related to childhood obesity currently. More rigorous longitudinal researches were required to disentangle the causations. However, the positive association of asprosin levels and total cholesterol indicated that asprosin might get involved in the lipid-metabolism of childhood obesity, asprosin might be a prospective bio-index and targeted treatment of total cholesterol metabolism besides the role of glucogenic and orexigenic. TRIAL REGISTRATION: Prospero ID: CRD42023426476.


Assuntos
Fibrilina-1 , Obesidade Infantil , Adulto , Animais , Criança , Humanos , Colesterol , Fibrilina-1/sangue , Glucose , Obesidade Infantil/sangue , Estudos Prospectivos
12.
Food Chem ; 448: 139043, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38552463

RESUMO

This study aimed to evaluate the potential of the bilayer emulsions stabilized with casein/butyrylated dextrin nanoparticles and chitosan as fat substitutes in preparing low-calorie sponge cakes. Among the different cake groups, the substitution of bilayer emulsions at 60% exhibited comparable baking properties, appearance, texture characteristics and stable secondary structure to fat. The specific volume and height were increased by 36.94% and 22%, respectively, while the cake showed higher lightness (L*) in the cores and softer hardness in the crumb. In addition, the moisture content of cakes was increased while the water activity remained unchanged. These results showed that casein/butyrylated dextrin bilayer emulsion was a potential fat substitute for cake products at the ratio of 60% with the desirable characteristics.


Assuntos
Caseínas , Quitosana , Dextrinas , Emulsões , Substitutos da Gordura , Nanopartículas , Quitosana/química , Nanopartículas/química , Caseínas/química , Dextrinas/química , Emulsões/química , Substitutos da Gordura/química , Culinária
13.
Atherosclerosis ; 391: 117478, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38417185

RESUMO

BACKGROUND AND AIMS: Atherosclerosis (AS) is a chronic inflammatory disease characterized by lipid infiltration and plaque formation in blood vessel walls. Ganoderic acids (GA), a class of major bioactive compounds isolated from the Chinese traditional medicine Ganoderma lucidum, have multiple pharmacological activities. This study aimed to determine the anti-atherosclerotic effect of GA and reveal the pharmacological mechanism. METHODS: ApoE-/- mice were fed a high-cholesterol diet and treated with GA for 16 weeks to induce AS and identify the effect of GA. Network pharmacological analysis was performed to predict the anti-atherosclerotic mechanisms. An invitro cell model was used to explore the effect of GA on macrophage polarization and the possible mechanism involved in bone marrow dereived macrophages (BMDMs) and RAW264.7 cells stimulated with lipopolysaccharide or oxidized low-density lipoprotein. RESULTS: It was found that GA at 5 and 25 mg/kg/d significantly inhibited the development of AS and increased plaque stability, as evidenced by decreased plaque in the aorta, reduced necrotic core size and increased collagen/lipid ratio in lesions. GA reduced the proportion of M1 macrophages in plaques, but had no effect on M2 macrophages. In vitro experiments showed that GA (1, 5, 25 µg/mL) significantly decreased the proportion of CD86+ macrophages and the mRNA levels of IL-6, IL-1ß, and MCP-1 in macrophages. Experimental results showed that GA inhibited M1 macrophage polarization by regulating TLR4/MyD88/NF-κB signaling pathway. CONCLUSIONS: This study demonstrated that GA play an important role in plaque stability and macrophage polarization. GA exert the anti-atherosclerotic effect partly by regulating TLR4/MyD88/NF-κB signaling pathways to inhibit M1 polarization of macrophages. Our study provides theoretical basis and experimental data for the pharmacological activity and mechanisms of GA against AS.


Assuntos
Aterosclerose , Placa Aterosclerótica , Camundongos , Animais , NF-kappa B/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Fator 88 de Diferenciação Mieloide/farmacologia , Receptor 4 Toll-Like/metabolismo , Aterosclerose/tratamento farmacológico , Aterosclerose/prevenção & controle , Aterosclerose/genética , Placa Aterosclerótica/metabolismo , Transdução de Sinais , Macrófagos/metabolismo , Lipídeos
14.
Curr Biol ; 34(6): 1161-1167.e3, 2024 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-38325374

RESUMO

Wood growth is key to understanding the feedback of forest ecosystems to the ongoing climate warming. An increase in spatial synchrony (i.e., coincident changes in distant populations) of spring phenology is one of the most prominent climate responses of forest trees. However, whether temperature variability contributes to an increase in the spatial synchrony of spring phenology and its underlying mechanisms remains largely unknown. Here, we analyzed an extensive dataset of xylem phenology observations of 20 conifer species from 75 sites over the Northern Hemisphere. Along the gradient of increase in temperature variability in the 75 sites, we observed a convergence in the onset of cell enlargement roughly toward the 5th of June, with a convergence in the onset of cell wall thickening toward the summer solstice. The increase in rainfall since the 5th of June is favorable for cell division and expansion, and as the most hours of sunlight are received around the summer solstice, it allows the optimization of carbon assimilation for cell wall thickening. Hence, the convergences can be considered as the result of matching xylem phenological activities to favorable conditions in regions with high temperature variability. Yet, forest trees relying on such consistent seasonal cues for xylem growth could constrain their ability to respond to climate warming, with consequences for the potential growing season length and, ultimately, forest productivity and survival in the future.


Assuntos
Traqueófitas , Temperatura , Ecossistema , Mudança Climática , Xilema , Estações do Ano , Árvores
15.
Psychiatry Res ; 334: 115815, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38422867

RESUMO

Our study focused on human brain transcriptomes and the genetic risks of cigarettes per day (CPD) to investigate the neurogenetic mechanisms of individual variation in nicotine use severity. We constructed whole-brain and intramodular region-specific coexpression networks using BrainSpan's transcriptomes, and the genomewide association studies identified risk variants of CPD, confirmed the associations between CPD and each gene set in the region-specific subnetworks using an independent dataset, and conducted bioinformatic analyses. Eight brain-region-specific coexpression subnetworks were identified in association with CPD: amygdala, hippocampus, medial prefrontal cortex (MPFC), orbitofrontal cortex (OPFC), dorsolateral prefrontal cortex, striatum, mediodorsal nucleus of the thalamus (MDTHAL), and primary motor cortex (M1C). Each gene set in the eight subnetworks was associated with CPD. We also identified three hub proteins encoded by GRIN2A in the amygdala, PMCA2 in the hippocampus, MPFC, OPFC, striatum, and MDTHAL, and SV2B in M1C. Intriguingly, the pancreatic secretion pathway appeared in all the significant protein interaction subnetworks, suggesting pleiotropic effects between cigarette smoking and pancreatic diseases. The three hub proteins and genes are implicated in stress response, drug memory, calcium homeostasis, and inhibitory control. These findings provide novel evidence of the neurogenetic underpinnings of smoking severity.


Assuntos
Estudo de Associação Genômica Ampla , Nicotina , Humanos , Transcriptoma , Encéfalo , Corpo Estriado
16.
Int J Biol Macromol ; 260(Pt 1): 129361, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38218280

RESUMO

Pectin is a promising nano-carrier. The degree of methyl esterification (DM) influences the physiochemical properties of pectin. However, the effect of DM on the encapsulation capacity of pectin remains unclear. In this work, low methyl-esterified pectin (LMP) and high methyl-esterified pectin (HMP) were prepared. The molecular weight, rheological properties of these pectins with various DM levels were determined. Then icaritin/pectin micelles (IPMs) were prepared using HMP and LMP. Notably, higher loading capacities (18.75-20.12 %) were observed in HMP-IPMs compared to LMP-IPMs (15.72-16.64 %). Furthermore, LMP-IPMs demonstrated a DM-dependent reduction in particle sizes, ranging from 449 to 527 nm. In contrast, the particle sizes of HMP-IPMs varied between 342 and 566 nm, with smaller particle sizes observed in HMP-IPMs at higher DM levels. A significant positive correlation was found between DM and the formation of IPMs, including encapsulation efficiency, loading capacity, Zeta potential, and polydispersity index. Alkali de-esterification showed a weak impact on the pectin structure. Hydroxyl groups like 7-OH and 5-OH of icaritin might be involved in the formation of IPMs. The hydrogen-bond interactions between pectin and icaritin could be enhanced as DM increased.


Assuntos
Flavonoides , Pectinas , Pectinas/química , Esterificação , Micelas
17.
J Econ Entomol ; 117(2): 388-400, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38266252

RESUMO

Artificial diets for silkworms overcome the seasonal limitations of traditional rearing methods with fresh mulberry leaves. However, the current wet artificial diets, steamed at high temperatures, are not favored by silkworms, and they are cumbersome and challenging to preserve. These conditions adversely affected the development of artificial diet-based sericulture production. In this study, we disinfected dry powder diets with radiation and added distilled water without steaming before use. Then, the nutritional value of finished diets and their impact on silkworm development was assessed. Compared with steamed diets, nonsteamed diets were more attractive to silkworms. Chemical assays showed significantly more essential nutrients for silkworms, including l-ascorbic acid, vitamin B1, vitamin B2, and urease in nonsteamed diets than in steamed diets. Feeding fifth-instar silkworm larvae with nonsteamed diets significantly improved the ammonia utilization efficiency of the diet and increased the cocoon shell rate and diet/silk protein conversion efficiency by 5.9% and 13.3%, respectively. When fed with nonsteamed diets, the abundance of aerobic microorganisms in silkworm intestines increased and the abundance of pathogenic bacteria decreased. Furthermore, the vitality of the silkworm, measured by the dead worm cocoon rate, significantly improved by 16.90%. In summary, preparing sterile wet diets without high-temperature steaming effectively improved the nutritional value of the diet and enhanced silkworm growth.


Assuntos
Bombyx , Morus , Animais , Seda/metabolismo , Dieta , Larva , Valor Nutritivo
18.
IEEE Trans Med Imaging ; 43(6): 2098-2112, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38241121

RESUMO

To address the lack of high-quality training labels in positron emission tomography (PET) imaging, weakly-supervised reconstruction methods that generate network-based mappings between prior images and noisy targets have been developed. However, the learned model has an intrinsic variance proportional to the average variance of the target image. To suppress noise and improve the accuracy and generalizability of the learned model, we propose a conditional weakly-supervised multi-task learning (MTL) strategy, in which an auxiliary task is introduced serving as an anatomical regularizer for the PET reconstruction main task. In the proposed MTL approach, we devise a novel multi-channel self-attention (MCSA) module that helps learn an optimal combination of shared and task-specific features by capturing both local and global channel-spatial dependencies. The proposed reconstruction method was evaluated on NEMA phantom PET datasets acquired at different positions in a PET/CT scanner and 26 clinical whole-body PET datasets. The phantom results demonstrate that our method outperforms state-of-the-art learning-free and weakly-supervised approaches obtaining the best noise/contrast tradeoff with a significant noise reduction of approximately 50.0% relative to the maximum likelihood (ML) reconstruction. The patient study results demonstrate that our method achieves the largest noise reductions of 67.3% and 35.5% in the liver and lung, respectively, as well as consistently small biases in 8 tumors with various volumes and intensities. In addition, network visualization reveals that adding the auxiliary task introduces more anatomical information into PET reconstruction than adding only the anatomical loss, and the developed MCSA can abstract features and retain PET image details.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador , Imagens de Fantasmas , Tomografia por Emissão de Pósitrons , Aprendizado de Máquina Supervisionado , Humanos , Processamento de Imagem Assistida por Computador/métodos , Tomografia por Emissão de Pósitrons/métodos , Imagem Corporal Total/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos
19.
J Agric Food Chem ; 72(3): 1618-1629, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38189644

RESUMO

Dietary prenylated stilbenoids, found in various food sources, offer multiple health benefits, including liver protection. However, the underlying mechanisms of hepatoprotection remain unclear. In this study, we synthesized 13 natural prenylated stilbenoids and examined their hepatoprotective activities, with silent mating type information regulation 2 homologue-1 (SIRT1) as the primary target for screening. Among all of the prenylated stilbenoids tested, 4-C-geranyl oxyresveratrol demonstrated superior performance. It activated SIRT1 activity more effectively than resveratrol, a well-known SIRT1 activator. To further investigate the mechanism of liver protection, two in vitro models were used: the palmitic acid-induced lipid accumulation model and the H2O2-induced apoptosis model. Our findings suggested that 4-C-geranyl oxyresveratrol mitigated lipid accumulation through the SIRT1-PGC1α pathway, reduced apoptosis via the SIRT1-p53-p21 pathway, and exerted antioxidant effects through the SIRT1-Nrf2 pathway. These findings provide new insights into the chemical basis of the health benefits of prenylated stilbenoids and their potential use as functional food additives.


Assuntos
Sirtuína 1 , Estilbenos , Sirtuína 1/metabolismo , Peróxido de Hidrogênio , Resveratrol , Estilbenos/metabolismo , Lipídeos
20.
Phytomedicine ; 124: 155326, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38185068

RESUMO

BACKGROUND: Cerebral ischemia-reperfusion injury (CIRI) is a phenomenon that pathological injury of ischemic brain tissue is further aggravated after the restoration of blood supply. The complex pathological mechanism of CIRI has led to the failure of multiple neuroprotective agents in clinical studies. Salvianolic acid A (SAA) is a neuroprotective extract from Salvia miltiorrhiza Bge., with significant pharmacological activities in the treatment of brain injury. However, the neuroprotective mechanisms of SAA remain unclear. PURPOSE: To explore the potential protective effect of SAA on CIRI and its mechanism, and to provide experimental basis for the research of new drugs for CIRI. STUDY DESIGN: A model of transient middle cerebral artery occlusion (tMCAO) in rats was used to simulate clinical CIRI, and the neuroprotective effect of SAA on tMCAO rats was investigated within 14 days after reperfusion. The improvement effects of SAA on cognitive impairment of tMCAO rats were investigated by behavioral tests from days 7-14. Finally, the neuroprotective mechanism of SAA was investigated on day 14. METHODS: The neuroprotective effects and mechanism of SAA were investigated by behavioral tests, HE and TUNEL staining, RNA sequence (RNA-seq) analysis and Western blot in tMCAO rats. RESULTS: The brain protective effects of SAA were achieved by alleviating cerebral infarction, cerebral edema, cerebral atrophy and nerve injury in tMCAO rats. Meanwhile, SAA could effectively improve the cognitive impairment and pathological damage of hippocampal tissue, and inhibit cell apoptosis in tMCAO rats. Besides, SAA could provide neuroprotective effects by up-regulating the expression of Bcl-2, inhibiting the activation of Caspase 3, and regulating PKA/CREB/c-Fos signaling pathway. CONCLUSION: SAA can significantly improve brain injury and cognitive impairment in CIRI rats, and this neuroprotective effect may be achieved through the anti-apoptotic effect and the regulation of PKA/CREB/c-Fos signaling pathway.


Assuntos
Lesões Encefálicas , Isquemia Encefálica , Ácidos Cafeicos , Lactatos , Fármacos Neuroprotetores , Traumatismo por Reperfusão , Ratos , Animais , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Ratos Sprague-Dawley , Transdução de Sinais , Isquemia Encefálica/patologia , Traumatismo por Reperfusão/metabolismo , Apoptose , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/patologia , Lesões Encefálicas/tratamento farmacológico
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