RESUMO
General anesthesia shares many similarities with natural sleep in behavior and electroencephalogram (EEG) patterns. The latest evidence suggests that general anesthesia and sleep-wake behavior may share overlapping neural substrates. The GABAergic neurons in the basal forebrain (BF) have recently been demonstrated to play a key role in controlling wakefulness. It was hypothesized that BF GABAergic neurons may participate in the regulation of general anesthesia. Here, using in vivo fiber photometry, we found that the activity of BF GABAergic neurons was generally inhibited during isoflurane anesthesia, having obviously decreased during the induction of anesthesia and being gradually restored during the emergence from anesthesia, in Vgat-Cre mice of both sexes. Activation of BF GABAergic neurons with chemogenetic and optogenetic approaches decreased sensitivity to isoflurane, delayed induction, and accelerated emergence from isoflurane anesthesia. Optogenetic activation of BF GABAergic neurons decreased EEG δ power and the burst suppression ratio (BSR) during 0.8% and 1.4% isoflurane anesthesia, respectively. Similar to the effects of activating BF GABAergic cell bodies, photostimulation of BF GABAergic terminals in the thalamic reticular nucleus (TRN) also strongly promoted cortical activation and behavioral emergence from isoflurane anesthesia. Collectively, these results showed that the GABAergic BF is a key neural substrate for general anesthesia regulation that facilitates behavioral and cortical emergence from general anesthesia via the GABAergic BF-TRN pathway. Our findings may provide a new target for attenuating the depth of anesthesia and accelerating emergence from general anesthesia.SIGNIFICANCE STATEMENT The basal forebrain (BF) is a key brain region controlling sleep-wake behavior. Activation of GABAergic neurons in the BF potently promotes behavioral arousal and cortical activity. Recently, many sleep-wake-related brain structures have been reported to participate in the regulation of general anesthesia. However, it is still unclear what role BF GABAergic neurons play in general anesthesia. In this study, we aim to reveal the role of BF GABAergic neurons in behavioral and cortical emergence from isoflurane anesthesia and elucidate the underlying neural pathways. Understanding the specific role of BF GABAergic neurons in isoflurane anesthesia would improve our understanding of the mechanisms of general anesthesia and may provide a new strategy for accelerating emergence from general anesthesia.
Assuntos
Prosencéfalo Basal , Isoflurano , Masculino , Feminino , Camundongos , Animais , Isoflurano/farmacologia , Prosencéfalo Basal/fisiologia , Neurônios GABAérgicos/fisiologia , Sono/fisiologia , Eletroencefalografia , Anestesia GeralRESUMO
Detecting harmful pathogens in food is not only a crucial aspect of food quality management but also an effective way to ensure public health. In this paper, a complete nuclear magnetic resonance biosensor based on a novel gadolinium (Gd)-targeting molecular probe was developed for the detection of Salmonella in milk. First, streptavidin was conjugated to the activated macromolecular polyaspartic acid (PASP) via an amide reaction to generate SA-PASP. Subsequently, the strong chelating and adsorption properties of PASP toward the lanthanide metal gadolinium ions were exploited to generate the magnetic complex (SA-PASP-Gd). Finally, the magnetic complex was linked to biotinylated antibodies to obtain the bioprobe and achieve the capture of Salmonella. Under optimal experimental conditions, the sensor we have constructed can achieve a rapid detection of Salmonella within 1.5 h, with a detection limit of 7.1 × 103 cfu mL-1.
Assuntos
Técnicas Biossensoriais , Gadolínio , Leite , Salmonella , Leite/microbiologia , Leite/química , Gadolínio/química , Animais , Salmonella/isolamento & purificação , Técnicas Biossensoriais/métodos , Espectroscopia de Ressonância Magnética , Limite de Detecção , Imunoensaio/métodosRESUMO
Traffic emissions are a dominant source of secondary organic aerosol (SOA) in urban environments. Though tailpipe exhaust has drawn extensive attention, the impact of non-tailpipe emissions on atmospheric SOA has not been well studied. Here, a closure study was performed combining urban tunnel experiments and dynamometer tests using an oxidation flow reactor in situ photo-oxidation. Results show a significant gap between field and laboratory research; the average SOA formation potential from real-world fleet is 639 ± 156 mg kg fuel-1, higher than the reconstructed result (188 mg kg fuel-1) based on dynamometer tests coupled with fleet composition inside the tunnel. Considering the minimal variation of SOA/CO in emission standards, we also reconstruct CO and find the critical role of high-emitting events in the real-world SOA burden. Different profiles of organic gases are detected inside the tunnel than tailpipe exhaust, such as more abundant C6-C9 aromatics, C11-C16 species, and benzothiazoles, denoting contributions from non-tailpipe emissions to SOA formation. Using these surrogate chemical compounds, we roughly estimate that high-emitting, evaporative emission, and asphalt-related and tire sublimation share 14, 20, and 10% of the SOA budget, respectively, partially explaining the gap between field and laboratory research. These experimental results highlight the importance of non-tailpipe emissions to atmospheric SOA.
Assuntos
Poluentes Atmosféricos , Emissões de Veículos , Emissões de Veículos/análise , Poluentes Atmosféricos/análise , Aerossóis/análise , OxirreduçãoRESUMO
Evidence mapping was performed to systematically search and review the clinical studies about the treatment of insomnia with Chinese patent medicines. The evidence distribution in this field was analyzed and the problems of the studies were summarized. Chinese-and English-language articles of the studies involving the Chinese patent medicines specified in three national drug catalogs for the treatment of insomnia were searched against the databases with the time interval from inception to August 2023. Figures and tables were established to present the results. Finally, 23 Chinese patent medicines were screened out, which were mentioned in 299 articles involving 236 randomized controlled trials(RCTs), 35 non-randomized controlled trials(non-RCTs), 7 retrospective studies, 17 systematic reviews/Meta-analysis, and 4 guidelines/expert recommendations or consensus. Bailemian Capsules, Wuling Capsules, and Yangxue Qingnao Granules were mentioned in a large proportion of articles. The outcome indicators included sleep rating scale, clinical response rate, safety indicators, and anxiety and depression scores. The results showed that the studies about the treatment of insomnia with Chinese patent medicines were growing. However, there was a scarcity of research evidence, and the available studies were single-center with small sample sizes and short periods. These studies spanned broad clinical scopes with inadequately emphasized advantages of TCM and insufficient outcome indicators about quality of life, follow-up, and recurrence rate. RCT exhibited a high risk of bias, and the systematic reviews/Meta-analysis demonstrated low overall quality. The retrospective studies received suboptimal scores, and the non-RCT failed to mention follow-up time, loss rate to follow-up, and sample size estimations, which compromised result reliability. It is recommended that the research protocol for Chinese patent medicines in treating insomnia should adhere to the clinical research standards of TCM. The TCM syndrome score can serves as a crucial outcome measure, and emphasis should be placed on patients' quality of life, follow-up, and recurrence prevention. Measures should be taken to enhance the accessibility and affordability of Chinese patent medicines and strengthen the connection between medical insurance policies and the policies pertaining to Chinese patent medicines. Furthermore, it is advisable to reasonably increase the inclusion of Chinese patent medicines with well-established efficacy and safety evidence in the category A list of medical insurance.
Assuntos
Medicamentos de Ervas Chinesas , Distúrbios do Início e da Manutenção do Sono , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Humanos , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos sem Prescrição/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
BACKGROUND: Stroke has been found to be highly correlated with the triglyceride-glucose (TyG) index. The relation between the TyG index changes and stroke, however, has seldom been reported, and current researches mentioning the TyG index concentrate on individual values. We aimed to investigate whether the level and the change of TyG index was associated with the incidence of stroke. METHODS: Sociodemographic, medical background, anthropometric and laboratory information were retrospectively collected. Classification was conducted using k-means clustering analysis. Logistic regressions were to determine the relationship between different classes with changes in the TyG index and incidence of stroke, taking the class with the smallest change as a reference. Meanwhile, restricted cubic spline regression was applied to examine the links of cumulative TyG index and stroke. RESULTS: 369 (7.8%) of 4710 participants had a stroke during 3 years. Compared to class 1 with the best control of the TyG Index, the OR for class 2 with good control was 1.427 (95% CI, 1.051-1.938), the OR for class 3 with moderate control was 1.714 (95% CI, 1.245-2.359), the OR for class 4 with worse control was 1.814 (95% CI, 1.257-2.617), and the OR for class 5 with consistently high levels was 2.161 (95% CI, 1.446-3.228). However, after adjusting for multiple factors, only class 3 still had an association with stroke (OR 1.430, 95%CI, 1.022-2.000). The relation between the cumulative TyG index and stroke was linear in restricted cubic spline regression. In subgroup analysis, similar results were shown in participants without diabetes or dyslipidemia. There is neither additive nor multiplicative interaction between TyG index class and covariates. CONCLUSION: A constant higher level with worst control in TyG index indicated a higher risk of stroke.
Assuntos
Glucose , Acidente Vascular Cerebral , Humanos , Pessoa de Meia-Idade , Incidência , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Triglicerídeos , Glicemia , Fatores de Risco , BiomarcadoresRESUMO
Hearing loss is a major risk factor for tinnitus, hyperacusis, and central auditory processing disorder. Although recent studies indicate that hearing loss causes neuroinflammation in the auditory pathway, the mechanisms underlying hearing loss-related pathologies are still poorly understood. We examined neuroinflammation in the auditory cortex following noise-induced hearing loss (NIHL) and its role in tinnitus in rodent models. Our results indicate that NIHL is associated with elevated expression of proinflammatory cytokines and microglial activation-two defining features of neuroinflammatory responses-in the primary auditory cortex (AI). Genetic knockout of tumor necrosis factor alpha (TNF-α) or pharmacologically blocking TNF-α expression prevented neuroinflammation and ameliorated the behavioral phenotype associated with tinnitus in mice with NIHL. Conversely, infusion of TNF-α into AI resulted in behavioral signs of tinnitus in both wild-type and TNF-α knockout mice with normal hearing. Pharmacological depletion of microglia also prevented tinnitus in mice with NIHL. At the synaptic level, the frequency of miniature excitatory synaptic currents (mEPSCs) increased and that of miniature inhibitory synaptic currents (mIPSCs) decreased in AI pyramidal neurons in animals with NIHL. This excitatory-to-inhibitory synaptic imbalance was completely prevented by pharmacological blockade of TNF-α expression. These results implicate neuroinflammation as a therapeutic target for treating tinnitus and other hearing loss-related disorders.
Assuntos
Córtex Auditivo/fisiopatologia , Perda Auditiva Provocada por Ruído/fisiopatologia , Estimulação Acústica , Animais , Vias Auditivas/fisiopatologia , Citocinas/metabolismo , Perda Auditiva/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neuroimunomodulação/imunologia , Ruído/efeitos adversos , Ratos , Ratos Sprague-Dawley , Zumbido/fisiopatologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Foods contaminated by foodborne pathogens have always been a great threat to human life. Herein, we constructed an electrochemical immunosensor for Salmonella detection by using a Fe3O4@graphene modified electrode. Because of the excellent electrical conductivity and mechanical stability of graphene and the large specific surface area of Fe3O4, the Fe3O4@graphene nanocomposite exhibits an excellent electrical signal, which greatly increased the sensitivity of the immunosensor. Gold nanoparticles were deposited on Fe3O4@graphene nanocomposite by electrochemical technology for the immobilization of the antibody. Cyclic voltammetry was selected to electrochemically characterize the construction process of immunosensors. The microstructure and morphology of related nanocomposites were analyzed by scanning electron microscopy. Under optimized experimental conditions, a good linear relationship was achieved in the Salmonella concentration range of 2.4 × 102 to 2.4 × 107 cfu/mL, and the limit of detection of the immunosensor was 2.4 × 102 cfu/mL. Additionally, the constructed immunosensor exhibited acceptable selectivity, reproducibility, and stability and provides a new reference for detecting pathogenic bacteria in milk.
Assuntos
Técnicas Biossensoriais , Grafite , Nanopartículas Metálicas , Nanocompostos , Animais , Técnicas Biossensoriais/veterinária , Carbono , Técnicas Eletroquímicas/veterinária , Eletrodos , Ouro/química , Grafite/química , Imunoensaio/veterinária , Limite de Detecção , Nanopartículas Metálicas/química , Leite , Nanocompostos/química , Reprodutibilidade dos Testes , SalmonellaRESUMO
Salmonella, as a common foodborne pathogen in dairy products, poses a great threat to human health. We studied a new detection method based on quantum dots (QD). A fluorescent biosensor with multiple fluorescent signal amplification based on a streptavidin (SA) biotin system and the polyamino linear polymer poly-l-lysine (PLL) were established to detect Salmonella in milk. First, Salmonella was captured on a black 96-well plate with paired Salmonella mAb to form a double-antibody sandwich. Second, SA was immobilized on biotin-modified mAb by SA-biotin specific bond. Then, the biotin-modified polylysine (BT-PLL) was bound on SA and specifically bonded again through the SA-biotin system. Finally, water-soluble CdSe/ZnS QD-labeled SA was added to a black 96-well plate for covalent coupling with BT-PLL. The fluorescent signal was amplified in a dendritic manner by the layer-by-layer overlap of SA and biotin and the covalent coupling of biotinylated PLL. Under optimal conditions, the detection limit was 4.9 × 103 cfu/mL in PBS. The detection limit was 10 times better than that of the conventional sandwich ELISA. In addition, the proposed biosensor was well specific and could be used for detecting Salmonella in milk samples.
Assuntos
Técnicas Biossensoriais , Pontos Quânticos , Animais , Técnicas Biossensoriais/veterinária , Biotina/química , Leite , Polilisina , Salmonella , Estreptavidina/químicaRESUMO
BACKGROUND: Seeking online health information (OHI) has become a common practice globally. The information seekers could face health risks if they are not proficient in OHI literacy. The OHI-seeking behaviors and skills of Chinese college students, the largest proportion of college students in the world, are understudied. This study was aimed to describe OHI-seeking behaviors and skills of college students in Guangdong, China. METHODS: College students in the Guangdong province with OHI-seeking experience were invited via WeChat, QQ, and Sina Weibo using QR code posters and flyers for participation in this online anonymized questionnaire-based study. Data on demographics, OHI literacy, information resources, search approaches, and behaviors were collected. The relationship between perceived OHI literacy and high-risk behaviors was investigated by bivariate logistic regression analysis. RESULTS: Respondents were 1203 college students with a mean age of 20.6 years, females (60.2%), and undergraduates (97.2%). They sought health information via websites (20.3%), WeChat (2.6%), or both (77.1%). Baidu was the main search engine, and baike.baidu.com (80.3%), Zhihu.com (48.4%), and Zhidao.baidu.com (35.8%) were top three among 20 searched websites for information about self-care (80.7%), general health (79.5%), disease prevention (77.7%), self-medication (61.2%), family treatment (40.9%), drugs (37.7%), western medications (26.6%), hospitals (22.7%), physicians (21.4%), and Traditional Chinese Medicine (15.6%). Despite most respondents (78%) lacked confidence in the evidence quality and satisfaction with the results, only 32.4% further consulted doctors. Many (> 50%) would recommend the retrieved information to others. About 20% experienced hacking/Internet fraud. Cronbach's alpha for the internal consistency of OHI literacy was 0.786. Bivariate logistic regression analysis showed that students who believed they can judge the evidence level of OHI were more likely to self-diagnose (OR = 2.2, 95%CI, 1.6-3.1) and look for drug usage (OR = 3.1, 95%CI, 1.9-5.0). CONCLUSIONS: This study reveals Chinese college students' heavy reliance on OHI to manage their own and others' health without sufficient knowledge/skills to identify misinformation and disinformation. The apparent risky information-seeking behaviors of Chinese college students warrant the provision of regulated, accurate, and actionable health information; assurance of cybersecurity; and health information literacy promotion in colleges by concerned authorities.
Assuntos
Letramento em Saúde , Comportamento de Busca de Informação , Adulto , China , Feminino , Humanos , Internet , Estudantes , Inquéritos e Questionários , Adulto JovemRESUMO
BACKGROUND: The aging population coupled with progressive medical technology has increased the demand for improved quality of end-of-life in China. However, implementation of an advance care planning (ACP) program in mainland China is still in its infancy owing to the significant influence of filial piety in Chinese culture. Research on implementation of ACP program among community health workers (CHWs) is limited. The current study sought to explore the willingness of CHWs to implement ACP based on the theory of planned behavior (TPB) and provide a reference for promotion of ACP in Chinese communities. METHODS: Phenomenological qualitative study using semi-structured face-to-face interviews. Interviews were audio-recorded. Colaizzi's method was used for data analysis. The study received ethical approval and all participants provided written consent. RESULTS: Thirteen CHWs from 3 community health service centers (CHSCs) in Hangzhou, Zhejiang Province, China were interviewed. Through the analysis of the interview content, we determined that most CHWs have a supportive attitude towards the implementation of ACP, the reasons for which are as follows: relieve suffering of patients and respect their medical autonomy; relieve economic and psychological burden on family members; promote development of community palliative care. However, some CHWs believe that the implementation of ACP will lead to doctor-patient disputes and medical risks. CHWs reported that the support of patients and their families, community lawyers, psychosocial professionals, and CHSCs senior managers helped them to implement ACP. In addition, they indicated that the improvement of doctor-patient communication ability, the improvement of community medical environment, the support of government policy, and the training of CHWs were the promoting factors influencing their implementation of ACP. The hindrance factors include insufficient allocation of community health human resources, imperfect ACP legislation in China, and deep-rooted traditional culture. CONCLUSION: Findings demonstrated that Chinese CHWs tend to support the implementation of ACP, but their willingness to implement is affected by different factors. CHSCs should actively organize standardized ACP training and comprehensively consider community medical environment, organizational norms, and human resources in implementation of ACP.
Assuntos
Planejamento Antecipado de Cuidados , Agentes Comunitários de Saúde , Idoso , China , Humanos , Intenção , Pesquisa QualitativaRESUMO
Rapid and sensitive detection technology is the key to preventing food-borne disease outbreaks. In this study, a low-field nuclear magnetic resonance (NMR) biosensor based on polyamidoamine dendrimers was prepared for the rapid detection of Salmonella in milk. The polyamidoamine dendrimer was biotinylated by amide reaction and chelated to diethylene triamine pentacetate acid and gadolinium to form magnetic complexes. The antibody and magnetic complexes were combined through a streptavidin-biotin system using streptavidin as an intermediate bridge to obtain the immunoprobe. Salmonella was captured by the immunoprobe via antigen-antibody interaction and then separated from the mixture by membrane filtration. Finally, the longitudinal relaxation signal of the filtrate was obtained by NMR. The biosensor had excellent anti-interference capability and could detect Salmonella within 1.5 h at a sensitivity of 103 cfu mL-1. This method based on NMR can realize detection in complex samples and has the potential to be a quick and nondestructive method for detecting target bacteria.
Assuntos
Técnicas Biossensoriais , Doenças Transmitidas por Alimentos/microbiologia , Gadolínio/química , Leite/microbiologia , Poliaminas/química , Salmonella/isolamento & purificação , Animais , Reações Antígeno-Anticorpo , Biotina/química , Dendrímeros/química , Feminino , Filtração , Doenças Transmitidas por Alimentos/prevenção & controle , Espectroscopia de Ressonância Magnética , Sensibilidade e Especificidade , Espectroscopia de Infravermelho com Transformada de Fourier , Estreptavidina/química , Fatores de TempoRESUMO
Rapid and sensitive detection of foodborne pathogens is of great importance for food safety. Here, a set of nuclear magnetic resonance (NMR) biosensors based on a O-carboxymethyl chitosan target gadolinium (Gd) probe was developed to quickly detect Salmonella in milk by combining NMR technology and bioimmunotechnology with membrane filtration technology. First, O-carboxymethyl chitosan (O-CMC) was biotinylated to prepare biotinylated O-carboxymethyl chitosan (biotin-O-CMC) through amide reaction, and biotinylated magnetic complexes (biotin-O-CMC-Gd) were obtained by using O-CMC, which has strong chelating adsorption on Gd. The target probe was obtained by combining biotin-O-CMC-Gd with the biotinylated antibody (biotin-antibody) via streptavidin (SA) by introducing the SA-biotin system. Then, Salmonella was captured by the target probe through antigen-antibody interaction. Finally, NMR was used to measure the longitudinal relaxation time (T1) of the filtrate collected by membrane filtration. This NMR biosensor with good specificity and high efficiency can detect Salmonella with the sensitivity of 1.8 × 103 cfu/mL within 2 h; in addition, it can realize the detection of complex samples because of its strong anti-interference capability and may open up a new method for rapid detection of Salmonella, which has a great application potential.
Assuntos
Técnicas Biossensoriais , Biotina , Animais , Técnicas Biossensoriais/veterinária , Quitosana/análogos & derivados , Gadolínio , Espectroscopia de Ressonância Magnética , Leite , Salmonella , EstreptavidinaRESUMO
Ubiquitin-conjugating enzymes are key factors in the ubiquitin proteasome pathway (UPP), which play key roles in ubiquitination. These enzymes affect the efficiency of UPP during stress conditions. P53 has important control of cell cycle arrest and apoptosis in response to cellular stress; these modifications are critical for the stability and transcriptional activity of p53 as the protein activates downstream target genes that dictate the cellular response. However, few studies have investigated the effects of thermal stress in turbot (Scophthalmus maximus), specifically the UPP signaling pathway, and the crosstalk between the ube2h and p53. In this study, the rapid amplification of cDNA ends was used to obtain a full-length cDNA of the turbot UBE2H gene (Sm-ube2h) and perform bioinformatics analysis. Our results showed that the cDNA of the Sm-ube2h was 718 bp in length, encoding a 189 amino acid protein, with a theoretical isoelectric point of 4.77. It also contained a catalytic (UBCc) domain. Expression of Sm-ube2h in different tissues was detected and quantified by qPCR, which was highest in the spleen and lowest in the liver. We also investigated the Sm-ube2h expression profiles in the liver and heart after thermal stress, and changes in Sm-ube2h and p53 under thermal stress, upon RNA interference. Our data speculated that Sm-ube2h and p53 exhibited antagonistic effects under normal temperature conditions after ube2h interference, but displayed synergistic effects under thermal stress, suggesting the crosstalk between UPP and p53 signaling pathway. Our results improved our understanding of the underlying molecular mechanism of thermal tolerance in turbot.
Assuntos
Linguados/metabolismo , Resposta ao Choque Térmico , Proteína Supressora de Tumor p53/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Linguados/genética , Fígado/enzimologia , Miocárdio/enzimologia , Filogenia , Homologia de Sequência de Aminoácidos , Enzimas de Conjugação de Ubiquitina/química , Enzimas de Conjugação de Ubiquitina/genéticaRESUMO
Turbot (Scophthalmus maximus) is an economically important marine fish cultured in China. In this study, fish in the experimental group were exposed to four temperatures: 15, 20, 25 and 28 °C. Metabolomics analysis and quantitative real-time PCR were used to assess changes in metabolic profiling and gene expression associated with thermal stress. The results showed the levels of heat shock protein 70 (HSP70), heat shock protein 90 (HSP90), blood creatinine and cortisol in S. maximus were all significantly upregulated (P < 0.05), indicating a stress response at 25 °C or higher. Challenge with thermal stress significantly increased expression levels of succinate dehydrogenase (SDH), fructose-1, 6-bisphosphatase (FBPase), malate dehydrogenase (MDH), cytosolic phosphoenolpyruvate carboxykinase (cPEPCK), glucose-6-phosphatase (G6Pase) and aspartate aminotransferase (AST) (P < 0.05). However, there was no effect on the expression levels of lactate dehydrogenase (LDH), alanine aminotransferase (ALT) and mitochondrial phosphoenolpyruvate carboxykinase (mPEPCK). Moreover, high temperature decreased levels of glycogenic amino acids, including histidine, threonine, glutamine, phenylalanine, arginine, serine, tyrosine, methionine and isoleucine. These findings suggest a significant correlation between gene expression and regulation of carbohydrate and amino acid metabolism in heat-stressed S. maximus kidney. In addition, the maintenance of aerobic metabolism and activation of gluconeogenesis appeared to be a critical metabolic strategy in combating heat stress in turbot kidney.
Assuntos
Linguados/fisiologia , Proteínas de Choque Térmico/metabolismo , Resposta ao Choque Térmico/fisiologia , Rim/metabolismo , Metaboloma , Animais , Testes Hematológicos/veterinária , Metabolômica , Reação em Cadeia da Polimerase em Tempo Real/veterináriaRESUMO
The induction of the myo-inositol biosynthesis (MIB) pathway in euryhaline fishes is an important component of the cellular response to osmotic challenge. The MIPS and IMPA1 genes were sequenced in turbot and found to be highly conserved in phylogenetic evolution, especially within the fish species tested. Under salinity stress in turbot, both MIPS and IMPA1 showed adaptive expression, a turning point in the level of expression occurred at 12 h in all tissues tested. We performed an RNAi assay mediated by long fragment dsRNA prepared by transcription in vitro. The findings demonstrated that knockdown of the MIB pathway weakened the function of gill osmotic regulation, and may induce a genetic compensation response in the kidney and gill to maintain physiological function. Even though the gill and kidney conducted stress reactions or compensatory responses to salinity stress, this inadequately addressed the consequences of MIB knockdown. Therefore, the survival time of turbot under salinity stress after knockdown was obviously less than that under seawater, especially under low salt stress. Pearson's correlation analysis between gene expression and dietary myo-inositol concentration indicated that the MIB pathway had a remarkable negative feedback control, and the dynamic equilibrium mediated by negative feedback on the MIB pathway played a crucial role in osmoregulation in turbot. An RNAi assay with c-Myc in vivo and the use of a c-Myc inhibitor (10058-F4) in vitro demonstrated that c-Myc was likely to positively regulate the MIB pathway in turbot.
Assuntos
Linguados/metabolismo , Inositol/biossíntese , Liases Intramoleculares/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Animais , Brânquias , Liases Intramoleculares/genética , Osmorregulação , Monoéster Fosfórico Hidrolases/genética , Proteínas Proto-Oncogênicas c-myc/genética , Salinidade , Equilíbrio HidroeletrolíticoRESUMO
The tumor suppressor protein, p53 plays a crucial role in protecting genetic integrity. Once activated by diverse cell stresses, p53 reversibly activates downstream target genes to regulate cell cycle and apoptosis. However, few studies have investigated the effects of thermal stress in turbot, specifically the p53 signaling pathway. In this study, the rapid amplification of cDNA ends was used to obtain a full-length cDNA of the turbot p53 gene (Sm-p53) and perform bioinformatics analysis. The results showed that the cDNA of the Sm-p53 gene was 2928 bp in length, encoded a 381 amino acid protein, with a theoretical isoelectric point of 6.73. It was composed of a DNA binding and a tetramerization domain. Expression of Sm-p53 in different tissues was detected and quantified by qRT-PCR, and was highest in the liver. We also investigated the expression profiles of Sm-p53 in different tissue and TK cells after thermal stress. These result suggested that Sm-p53 plays a key role, and provides a theoretical basis for Sm-p53 changes in environmental stress responses in the turbot.
Assuntos
Proteínas de Peixes/genética , Linguados/genética , Resposta ao Choque Térmico/genética , Rim/citologia , Proteína Supressora de Tumor p53/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , Proteínas de Peixes/química , Regulação da Expressão Gênica , Proteína Supressora de Tumor p53/químicaRESUMO
The pituitary hormone prolactin (PRL) regulates salt and water homeostasis by altering ion retention and water uptake through peripheral osmoregulatory organs. To understand the role of PRL and its receptor (PRLR) in hypoosmoregulation of turbot (Scophthalmus maximus), we characterized the PRL and PRLR gene and analyzed the tissue distribution of the two genes and their gene transcriptional patterns in the main expressed tissues under long-term and short-term low salt stress. The PRL cDNA is 1486 bp in length, incorporating an ORF of 636 bp with a putative primary structure of 211 residues. And the PRLR cDNA is 2849 bp in length, incorporating an ORF of 1944 bp with a putative primary structure of 647 residues. The deduced amino acid sequences of these two genes shared highly conserved structures with those from other teleosts. Quantitative real-time PCR results showed that PRL transcripts were strongly expressed in the pituitary and very weakly in brain, but were hardly expressed in other tissues. PRLR transcripts were most abundant in the kidney, to a lesser extent in the gill, intestine, brain, and spleen, and at low levels in the pituitary and other tissues examined. The expression of PRL in the pituitary increased after short-term or long-term low salt stress, and the highest expression level appeared 12 h after stress (P < 0.05). And there is no significant difference between both low salt group (5 ppt and 10 ppt) at each sampling point. The variation of PRLR expression in gill under short-term low salt stress is similar to that of PRL gene in pituitary, with highest value in 12 h (P < 0.05). However, the expression under long-term low salt stress was significantly higher than control group even than 12 h group under 5 ppt (P < 0.05). The expression of PRLR in the kidney increased first and then decreased after low salt stress, and the highest value also appeared in 12 h after stress and there was no significant difference between the salinity groups. After long-term low salt stress, the expression level also increased significantly (P < 0.05), but it was flat with 24 h, which was lower than 12 h. The variation of PRLR expression in the intestine was basically consistent with that in the kidney. The difference was that the expression level of 24 h after stress in the 5 ppt group was significantly higher than that of the 10 ppt group (P < 0.05). After a comprehensive analysis of the expression levels of the two genes, it can be found that the expression level increased and peaked at 12 h after short-term low salt stress, indicating that this time point is the key point for the regulation of turbot in response to low salt stress. This also provides very important information for studying the osmotic regulation of turbot. In addition, our results also showed that the expression of PRLR was stable in the kidney and intestine after long-term low salt stress, while the expression in the gill was much higher than short-term stress. It suggested that PRL and its receptors mainly exert osmotic regulation function in the gill under long-term low salt stress. At the same time, such a result also brings a hint for the low salt selection of turbot, focusing on the regulation of ion transport in the gill.
Assuntos
Linguados/fisiologia , Prolactina/metabolismo , Receptores da Prolactina/metabolismo , Estresse Salino/fisiologia , Animais , DNA Complementar , Brânquias , Hipófise , Hormônios Hipofisários , SalinidadeRESUMO
Blast-induced tinnitus is a prevalent problem among military personnel and veterans, as blast-related trauma damages the vulnerable microstructures within the cochlea, impacts auditory and non-auditory brain structures, and causes tinnitus and other disorders. Thus far, there is no effective treatment of blast-induced tinnitus due to an incomplete understanding of its underlying mechanisms, necessitating development of reliable animal models. This article focuses on recent animal studies using behavioral, electrophysiological, imaging, and pharmacological tools. The mechanisms underlying blast-induced tinnitus are largely similar to those underlying noise-induced tinnitus: increased spontaneous firing rates, bursting, and neurosynchrony, Mn++ accumulation, and elevated excitatory synaptic transmission. The differences mainly lie in the data variability and time course. Noise trauma-induced tinnitus mainly originates from direct peripheral deafferentation at the cochlea, and its etiology subsequently develops along the ascending auditory pathways. Blast trauma-induced tinnitus, on the other hand, results from simultaneous impact on both the peripheral and central auditory systems, and the resultant maladaptive neuroplasticity may also be related to the additional traumatic brain injury. Consequently, the neural correlates of blast-induced tinnitus have different time courses and less uniform manifestations of its neural correlates.
Assuntos
Traumatismos por Explosões/fisiopatologia , Modelos Animais de Doenças , Zumbido/fisiopatologia , Estimulação Acústica/efeitos adversos , Estimulação Acústica/métodos , Animais , Comportamento Animal , Traumatismos por Explosões/etiologia , Traumatismos por Explosões/metabolismo , Conectoma , Potenciais Evocados Auditivos , Zumbido/etiologia , Zumbido/metabolismoRESUMO
Magnetic nanoparticles (NPs) are emerging as promising candidates for the next generation of image contrast agents and their performance is largely dependent on physicochemical properties. In this paper, a new type of 'top-down' fabrication technique was developed to synthesize ultrasmall magnetic NPs as a contrast enhancer. In a detailed, home-made oxygen plasma generator, fragments of larger KMnF3 NPs (22 nm) were broken down into smaller (<5 nm) particles with enhanced hydrophilicity. As massive activated oxygen species were produced during the process, the plasma was able to severely etch the NPs, and vacuum UV light irradiated them heavily as well, leaving them with weak crystallinity, splitting them into ultrafine particles. Also their surface transformed from hydrophobic to hydrophilic by oxidizing the passivated ligand, evidenced by the spectroscopy and microscopy results. The fragmented NPs are characteristic of unprecedented high longitudinal relaxivity (r1 = 35.52 mM-1.s-1) and appropriate biocompatibility. In a healthy mouse, the ultrafine NPs did not exert observable toxicity, this was evaluated by histology of the main organs and hemogram analysis, including kidney and liver function analysis. More interestingly, the ultrasmall NPs had a very long circulation time, as its blood half-life was around 20 h. When applied as a contrast enhancer for MRI of the patient-derived tumor xenograft model, the accumulation of KMnF3 NPs within the tumor had an average of 12.13% ID per gram, which greatly shortened the relaxation time of the tumor. Therefore the control-to-noise ratio was significantly enhanced, relative to the same dosage of Gadopentetetic acid (Magvenist) (P < 0.001). Our primary results demonstrate that fragmentation of the NPs via our home-made oxygen plasma technique might be an effective route for fabricating ultrasmall NPs, and benefit their contrast effect when applied as MRI enhancers for clinical diagnosis of tumors.
Assuntos
Meios de Contraste/química , Imageamento por Ressonância Magnética/métodos , Nanopartículas/química , Oxigênio/química , Gases em Plasma/química , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Sobrevivência Celular/efeitos dos fármacos , Meia-Vida , Humanos , Cinética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/toxicidade , Nanopartículas/ultraestrutura , Células RAW 264.7RESUMO
OBJECTIVE: Oxidative stress plays a critical role in the development of abdominal aortic aneurysm (AAA). Intermedin (IMD) is a regulator of oxidative stress. Here, we investigated whether IMD reduces AAA by inhibiting oxidative stress. APPROACH AND RESULTS: In angiotensin II-induced ApoE-/- mouse and CaCl2-induced C57BL/6J mouse model of AAA, IMD1-53 significantly reduced the incidence of AAA and maximal aortic diameter. Ultrasonography, hematoxylin, and eosin staining and Verhoeff-van Gieson staining showed that IMD1-53 significantly decreased the enlarged aortas and elastic lamina degradation induced by angiotensin II or CaCl2. Mechanistically, IMD1-53 attenuated oxidative stress, inflammation, vascular smooth muscle cell apoptosis, and matrix metalloproteinase activation. IMD1-53 inhibited the activation of redox-sensitive signaling pathways, decreased the mRNA and protein expression of nicotinamide adenine dinucleotide phosphate oxidase subunits, and reduced the activity of nicotinamide adenine dinucleotide phosphate oxidase in AAA mice. Expression of Nox4 was upregulated in human AAA segments and in angiotensin II-treated mouse aortas and was markedly decreased by IMD1-53. In vitro, vascular smooth muscle cells with small-interfering RNA knockdown of IMD showed significantly increased angiotensin II-induced reactive oxygen species, and small-interfering RNA knockdown of Nox4 markedly inhibited the reactive oxygen species. IMD knockdown further increased the apoptosis of vascular smooth muscle cells and inflammation, which was reversed by Nox4 knockdown. Preincubation with IMD17-47 and protein kinase A inhibitor H89 inhibited the effect of IMD1-53, reducing Nox4 protein levels. CONCLUSIONS: IMD1-53 could have a protective effect on AAA by inhibiting oxidative stress.