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Pyruvate lies at a pivotal node of carbon metabolism in eukaryotes. It is involved in diverse metabolic pathways in multiple organelles, and its interorganelle shuttling is crucial for cell fitness. Many apicomplexan parasites harbor a unique organelle called the apicoplast that houses metabolic pathways like fatty acid and isoprenoid precursor biosyntheses, requiring pyruvate as a substrate. However, how pyruvate is supplied in the apicoplast remains enigmatic. Here, deploying the zoonotic parasite Toxoplasma gondii as a model apicomplexan, we identified two proteins residing in the apicoplast membranes that together constitute a functional apicoplast pyruvate carrier (APC) to mediate the import of cytosolic pyruvate. Depletion of APC results in reduced activities of metabolic pathways in the apicoplast and impaired integrity of this organelle, leading to parasite growth arrest. APC is a pyruvate transporter in diverse apicomplexan parasites, suggesting a common strategy for pyruvate acquisition by the apicoplast in these clinically relevant intracellular pathogens.
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Apicoplastos , Ácido Pirúvico , Toxoplasma , Apicoplastos/metabolismo , Toxoplasma/metabolismo , Ácido Pirúvico/metabolismo , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/genética , Animais , Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Membrana Transportadoras/genética , Transporte Biológico , Redes e Vias MetabólicasRESUMO
[This corrects the article DOI: 10.1371/journal.ppat.1010665.].
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The lumen of the endoplasmic reticulum (ER) is the subcellular site where secretory protein folding, glycosylation and sulfation of membrane-bound proteins, proteoglycans, and lipids occur. The protein folding and degradation in the lumen of the ER require high levels of energy in the form of ATP. Biochemical and genetic approaches show that ATP must first be translocated across ER membrane by particular transporters before serving as substrates and energy sources in the lumenal reactions. Here we describe an ATP/ADP transporter residing in the ER membranes of T.gondii. Immunofluorescence (IFA) assay in transgenic TgANT1-HA tag revealed that TgANT1 is a protein specifically expressed in the ER. In vitro assays, functional integration of TgANT in the cytoplasmic membrane of intact E. coli cells reveals high specificity for an ATP/ADP antiport. The depletion of TgANT leads to fatal growth defects in T.gondii, including a significant slowdown in replication, no visible plaque formation, and reduced ability to invade. We also found that the amino acid mutations in two domains of TgANT lead to the complete loss of its function. Since these two domains are conserved in multiple species, they may share the same transport mechanism. Our results indicate that TgANT is the only ATP/ADP transporter in the ER of T. gondii, and the lack of ATP in the ER is the cause of the death of T. gondii.
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Toxoplasma , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Retículo Endoplasmático/metabolismo , Escherichia coli/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Toxoplasma/genética , Toxoplasma/metabolismoRESUMO
BACKGROUND: The diagnostic criteria for Parkinson's disease (PD) remain complex, which is especially problematic for nonmovement disorder experts. A test is required to establish a diagnosis of PD with improved accuracy and reproducibility. OBJECTIVE: The study aimed to investigate the sensitivity and specificity of tests using sniffer dogs to diagnose PD. METHODS: A prospective, diagnostic case-control study was conducted in four tertiary medical centers in China to evaluate the accuracy of sniffer dogs to distinguish between 109 clinically established medicated patients with PD, 654 subjects without PD, 37 drug-naïve patients with PD, and 185 non-PD controls. The primary outcomes were sensitivity and specificity of sniffer dog's identification. RESULTS: In the study with patients who were medicated, when two or all three sniffer dogs yielded positive detection results in a sample tested, the index test sensitivity, specificity, and positive and negative likelihood ratios were 91% (95% CI: 84%-96%), 95% (95% CI: 93%-97%), and 19.16 (95% CI: 13.52-27.16) and 0.10 (95% CI: 0.05-0.17), respectively. The corresponding sensitivity, specificity, and positive and negative likelihood ratios in patients who were drug-naïve were 89% (95% CI: 75%-96%), 86% (95% CI: 81%-91%), and 6.6 (95% CI: 4.51-9.66) and 0.13 (95% CI: 0.05-0.32), respectively. CONCLUSIONS: Tests using sniffer dogs may be a useful, noninvasive, fast, and cost-effective method to identify patients with PD in community screening and health prevention checkups as well as in neurological practice. © 2022 International Parkinson and Movement Disorder Society.
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Doença de Parkinson , Animais , Estudos de Casos e Controles , Cães , Humanos , Doença de Parkinson/diagnóstico , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Cães TrabalhadoresRESUMO
BACKGROUND: The naked mole-rat (NMR, Heterocephalus glaber) is being bred as a novel laboratory animal due to its unique biological characteristics, including longevity, cancer resistance, hypoxia tolerance, and pain insensitivity. It is expected that differences exist between the microbiota of wild NMRs and that of NMRs in an artificial environment. Overall, the effect of environment on changes in the NMR microbiota remains unknown. In an attempt to understand the microbiota composition of NMRs in captivity, variability in the microbiota of the intestinal and respiratory tracts of two groups of NMRs was assessed under two conditions. RESULTS: The results obtained by high-throughput sequencing revealed significant differences at the phylum, class, order, family and genus levels in the microbiota between the two groups of NMRs examined (first group in conventional environment, second group in barrier environment). For the trachea, 24 phyla and 533 genera and 26 phyla and 733 genera were identified for the first and second groups of animals. Regarding the cecum, 23 phyla and 385 genera and 25 phyla and 110 genera were identified in the microbiota of first and second groups of animals. There were no obvious differences between females and males or young and adult animals. CONCLUSIONS: Our results suggest that the intestinal and respiratory tract NMR microbiota changed during captivity, which may be related to the transition to the breeding environment. Such changes in the microbiota of NMRs may have an effect on the original characteristics, which may be the direction of further research studies.
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Bactérias/classificação , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Intestinos/microbiologia , Microbiota , Ratos-Toupeira/microbiologia , Filogenia , Sistema Respiratório/microbiologia , Fatores Etários , Animais , Bactérias/genética , Bactérias/isolamento & purificação , Biodiversidade , Ceco/microbiologia , Modelos Animais de Doenças , Feminino , Masculino , Fatores Sexuais , Traqueia/microbiologiaRESUMO
OBJECTIVE: To determine the protective effect of zero-balanced ultrafiltration and modified ultrafiltration on infants' pulmonary function after cardiac surgery. METHODS: Sixty infants with congenital heart diseases were randomly divided into 3 groups: a zero-balanced ultrafiltration group (Z group), a modified ultrafiltration group (M group) and a zero-balanced ultrafiltration with modified ultrafiltration group (Z+M group). Oxygenation index (OI), difference of alveoli-arterial oxygen pressure (P(A-α)O2), static lung compliance (Cstat), and airway resistance (Raw) were measured before caridopulmonary bypass (CPB, T1), 20 minutes after the CPB (T2), 2 h after the operation (T3), 6 h after the operation (T4) and 12 h after the operation (T5). The time of mechanical ventilation was also monitored. RESULTS: After the CPB, OI and Cstat in all groups decreased significantly, while Raw and P(A-α)O2 increased significantly. At T3, T4 and T5, OI and Cstat in the Z+M group were significantly higher than those in the Z group and the M group (P<0.05), Raw and P(A-α)O2 in the Z+M group were significantly lower than those in the Z group and the M group (P<0.05). The ventilation time in the Z+M group was significantly shorter than that in the Z group and the M group (P<0.05). CONCLUSION: Zero-balanced ultrafiltration and modified ultrafiltration can effectively promote the pulmonary function after cardiac surgery in infants.
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Procedimentos Cirúrgicos Cardíacos , Pulmão/fisiologia , Ultrafiltração , Cardiopatias Congênitas/cirurgia , Humanos , Lactente , Testes de Função RespiratóriaRESUMO
Background: Anxiety is common in patients with chronic obstructive pulmonary disease (COPD), especially in older patients with the definition of age over 60 years old. Few studies have focused on anxiety in older COPD patients. This study aimed to analyze the risk factors of anxiety in older COPD patients and the impacts of anxiety on future acute exacerbation. Methods: The general information, questionnaire data, previous acute exacerbation and pulmonary function were collected. Hamilton Anxiety Rating Scale (HAMA) was used to evaluate the anxiety of older COPD patients. The patients were followed up for one year, the number and the degrees of acute exacerbations of COPD were recorded. Results: A total of 424 older COPD patients were included in the analysis. 19.81% (N = 84) had anxiety symptoms, and 80.19% (N = 340) had no anxiety symptoms. There were increased pack-years, more comorbidities, and more previous acute exacerbations in older COPD patients with anxiety compared to those without anxiety (P < 0.05). Meanwhile, a higher modified Medical Research Council (mMRC), a higher COPD assessment test (CAT) score and a shorter six-minute walking distance (6MWD) were found in older COPD patients with anxiety (P < 0.05). The BODE index, mMRC, CAT score, comorbidities and acute exacerbations were associated with anxiety. Eventually, anxiety will increase the risk of future acute exacerbation in older COPD patients (OR = 4.250, 95% CI: 2.369-7.626). Conclusion: Older COPD patients with anxiety had worsening symptoms, more comorbidities and frequent acute exacerbation. Meanwhile, anxiety may increase the risk of acute exacerbation in the future. Therefore, interventions should be provided to reduce the risk of anxiety in older COPD patients at an early stage.
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Shale gas has been developed as an alternative to conventional energy worldwide, resulting in a large amount of shale gas fracturing flowback and produced water (FPW). Previous studies focus on total dissolved solids reduction using membrane desalination. However, there is a lack of efficient and stable techniques to remove organic pollutants, resulting in severe membrane fouling in downstream processes. This review focuses on the concentration and chemical composition of organic matter in shale gas FPW in China, as well as the hazards of organic pollutants. Organic removal techniques, including advanced oxidation processes, coagulation, sorption, microbial degradation, and membrane treatment are systematically reviewed. In particular, the influences of high salt on each technique are highlighted. Finally, different treatment techniques are evaluated in terms of energy consumption, cost, and organic removal efficiency. It is concluded that integrated coagulation-sorption-Fenton-membrane filtration represents a promising treatment process for FPW. This review provides valuable information for the feasible design, practical operation, and optimization of FPW treatment.
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Background: Ovarian hormones play a critical role in emotion processing, which may be a major reason for the high rates of major depressive disorders in women. However, the exact roles of estradiol and progesterone in emotional processing remain unclear. To this end, we performed behavioral and rs-fMRI studies on the effects ovarian hormones on disgust emotion. Methods: In Experiment 1, 95 Chinese female undergraduates completed the single category implicit association test (SC-IAT) and explicit measures of disgust intensity task, 32 in the menstrual phase, 30 in the follicular phase, and 33 in the luteal phase. In Experiment 2, A total of 25 healthy female undergraduates completed three sessions of the rs-fMRI. The menstrual group was scanned during cycle days 2-5, the follicular group during cycle during days 10-13, and the luteal group was scanned 3-7 days before the next menstruation. Results: The behavioral results showed that women during the luteal phase had higher D scores and shorter response times (RTs) to disgust stimuli compared to the menses and follicular phases. In contrast, women during the follicular phase had fewer feelings of disgust and longer RTs to pathogen stimuli compared with that during the menses and luteal phases, but this effect was moderated by the intensity of the stimuli. rs-fMRI studies showed that women during the luteal phase have higher functional connectivity in the salience network than those in the follicular phase. Compared with the menstrual phase, women have lower functional connectivity in the amygdala during the follicular phase. Conclusion: In summary, a more negative attitude to disgust stimuli and the enhanced functional connectivity of the salience network during the luteal phase may be associated with high progesterone levels, whereas lower disgust feelings and reduced functional connectivity of the amygdala during the follicular phase may be associated with high estradiol levels.
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Metabolism associated with energy production is highly compartmentalized in eukaryotic cells. During this process, transporters that move metabolites across organelle membranes play pivotal roles. The highly conserved ADP/ATP carrier (AAC) involved in ATP and ADP exchange between the mitochondria and cytoplasm is key to linking the metabolic activities in these 2 compartments. The ATP produced in mitochondria can be exchanged with cytoplasmic ADP by AAC, thus satisfying the energy needs in the cytoplasm. Toxoplasma gondii is an obligate intracellular parasite with a wide range of hosts. Previous studies have shown that mitochondrial metabolism helps Toxoplasma to parasitize diverse host cells. Here, we identified 2 putative mitochondria ADP/ATP carriers in Toxoplasma with significant sequence similarity to known AACs from other eukaryotes. We examined the ATP transport function of TgAACs by expressing them in Escherichia coli cells and found that only TgAAC1 had ATP transport activity. Moreover, knockdown of TgAAC1 caused severe growth defects of parasites and heterologous expression of mouse ANT2 in the TgAAC1 depletion mutant restored its growth, revealing its importance for parasite growth. These results verified that TgAAC1 functions as the mitochondrial ADP/ATP carrier in T. gondii and the functional studies demonstrated the importance of TgAAC1 for tachyzoites growth. IMPORTANCE T. gondii has an efficient and flexible energy metabolism system to meet different growth needs. ATP is an energy-carrying molecule and needs to be exchanged between organelles with the assistance of transporters. However, the function of TgAACs has yet to be characterized. Here, we identified 2 putative AACs of T. gondii and verified that only TgAAC1 had ATP transport activity with expression in the intact E. coli cells. Detailed analyses found that TgAAC1 is critical for the growth of tachyzoites and TgAAC2 is dispensable. Moreover, complementation with mouse ANT2 restored the growth speed of iTgAAC1, further suggesting TgAAC1 functions as a mitochondrial ADP/ATP carrier. Our research demonstrated the importance of TgAAC1 for tachyzoites growth.
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Parasitos , Toxoplasma , Animais , Camundongos , Parasitos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Mitocôndrias/metabolismo , Trifosfato de Adenosina/metabolismoRESUMO
Toxoplasma gondii (T. gondii) bradyzoites facilitate chronic infections that evade host immune response. Furthermore, reactivation in immunocompromised individuals causes severe toxoplasmosis. The presence of abundant granules containing the branched starch amylopectin is major characteristic of bradyzoites that is nearly absent from tachyzoites that drive acute disease. T. gondii genome encodes to potential Starch branching enzyme 1 (SBE1) that creates branching during amylopectin biosynthesis. However, the physiological function of the amylopectin in T. gondii remains unclear. In this study, we generated a SBE1 knockout parasites and revealed that deletion of SBE1 caused amylopectin synthesis defects while having no significant impact on the growth of tachyzoites under normal culture conditions in vitro as well as virulence and brain cyst formation. Nevertheless, SBE1 knockout decreased the influx of exogenous glucose and reduced tachyzoites proliferation in nutrition-deficient conditions. Deletion of SBE1 together with the α-amylase (α-AMY), responsible for starch digestion, abolished amylopectin production and attenuated virulence while restoring brain cyst formation. In addition, cysts with defective amylopectin metabolism showed abnormal morphology and were avirulent to mice. In conclusion, SBE1 is essential for the synthesis of amylopectin, which serves as energy storage during the development and reactivation of bradyzoites. IMPORTANCE Toxoplasmosis has become a global, serious public health problem due to the extensiveness of the host. There are great differences in the energy metabolism in the different stages of infection. The most typical difference is the abundant accumulation of amylopectin granules in bradyzoites, which is almost absent in tachyzoites. Until now, the physiological functions of amylopectin have not been clearly elucidated. We focused on starch branching enzyme 1 (SBE1) in the synthesis pathway to reveal the exact physiological significance of amylopectin. Our study clarified the role of SBE1 in the synthesis pathway and amylopectin in tachyzoites and bradyzoites, and demonstrated that amylopectin, as an important carbon source, was critical to parasites growth under an unfavorable environment and the reactivation of bradyzoites to tachyzoites. The findings obtained from our study provides a new avenue for the development of Toxoplasma vaccines and anti-chronic toxoplasmosis drugs.
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Enzima Ramificadora de 1,4-alfa-Glucana , Amilopectina , Proteínas de Protozoários , Toxoplasma , Toxoplasmose , Enzima Ramificadora de 1,4-alfa-Glucana/metabolismo , Amilopectina/biossíntese , Animais , Camundongos , Proteínas de Protozoários/metabolismo , Toxoplasma/enzimologia , Toxoplasma/genética , VirulênciaRESUMO
The attachment and colonization process of microorganisms on a carrier is an interdisciplinary research field. Through a series of physical, chemical, and biological actions, the microorganisms can eventually reproduce on the carrier. This article introduces biofilm start-up and its applications, and explores the current issues to look forward to future development directions. Firstly, the mechanism of microbial film formation is analyzed from the microbial community colonization and reproduction process. Secondly, when analyzing the factors influencing microbial membrane formation, the effect of microbial properties (e.g., genes, proteins, lipids) and external conditions (i.e., carrier, operating environment, and regulation mechanism among microbial communities) were discussed in depth. Aimed at exploring the mechanisms and influencing factors of biofilm start-up, this article proposes the application measures to strengthen this process. Finally, the problems encountered and the future development direction of the technology are analyzed and prospected.
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Microbiota , Águas Residuárias , BiofilmesRESUMO
Post-stroke depression (PSD) is the most common and serious sequelae of stroke. Approximately 33% of stroke survivors were affected by PSD. However, many issues (e.g., incidence, diagnostic marker, and risk factor) related to PSD remained unclear. The "monoamine hypothesis" is a significant hypothesis for depression, which suggests that three monoamines play a key role in depression. Therefore, most current antidepressants are developed to modulate the monoamines on PSD treatment, and these antidepressants have good effects on patients with PSD. However, the potential mechanisms of three monoamines in PSD are still unclear. Previously, we proposed "three primary emotions," which suggested a new model of basic emotions based on the three monoamines. It may provide a new way for PSD treatment. In addition, recent studies have found that monoamine-related emotional intervention also showed potential effects in the treatment and prevention of PSD. This study discusses these issues and attempts to provide a prospect for future research on PSD.
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Background and aims: The metabolomic profile of a biofluid can be affected by age, and thus provides detailed information about the metabolic alterations in biological processes and reflects the in trinsic rule regulating the growth and developmental processes. Methods: To systemically investigate the characteristics of multiple metabolic profiles associated with canine growth, we analyzed the metabolomics in the plasma and urine samples from 15 young and 15 adult beagle dogs via UHPLC-Q-TOFMS-based metabolomics. Blood routine and serum biochemical analyses were also performed on fasting blood samples. Results: The metabolomics results showed remarkable differences in metabolite fingerprints both in plasma and urine between the young and adult groups. The most obvious age-related metabolite alterations include decreased serumlevels of oxoglutaric acid and essential amino acids and derivatives but increased levels of urine levels of O-acetylserine. These changes primarily involved in amino acid metabolism and bile secretion pathways. We also found that the levels of glutamine were consistently higher in both serum and urine of adults, while N-acetylhistamine and uracil concentrations were much lower in the adult group compared to younger ones. Conclusion: Our study provides a whole metabolic profile of serum and urine characteristics of young and adult canines, identifying several metabolites that were significantly associated with age change, which provides theoretical support for the nutrition-related research and age-related homeostasis maintenance in dogs.
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Toxoplasma gondii (T. gondii) is an obligate intracellular parasite that can infect almost all warm-blooded animals, causing serious public health problems. Lysine crotonylation (Kcr) is a newly discovered posttranslational modification (PTM), which is first identified on histones and has been proved relevant to procreation regulation, transcription activation, and cell signaling pathway. However, the biological functions of histone crotonylation have not yet been reported in macrophages infected with T. gondii. As a result, a total of 1,286 Kcr sites distributed in 414 proteins were identified and quantified, demonstrating the existence of crotonylation in porcine alveolar macrophages. According to our results, identified histones were overall downregulated. HDAC2, a histone decrotonylase, was found to be significantly increased, which might be the executor of histone Kcr after parasite infection. In addition, T. gondii infection inhibited the crotonylation of H2B on K12, contributing on the suppression of epigenetic regulation and NF-κB activation. Nevertheless, the reduction of histone crotonylation induced by parasite infection could promote macrophage proliferation via activating PI3K/Akt signaling pathway. The present findings point to a comprehensive understanding of the biological functions of histone crotonylation in porcine alveolar macrophages, thereby providing a certain research basis for the mechanism research on the immune response of host cells against T. gondii infection.
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Crotonatos/metabolismo , Histonas/metabolismo , Ativação de Macrófagos , Macrófagos Alveolares/parasitologia , Toxoplasma/parasitologia , Toxoplasmose/parasitologia , Animais , Linhagem Celular , Proliferação de Células , Epigênese Genética , Interações Hospedeiro-Parasita , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/metabolismo , NF-kappa B/metabolismo , Processamento de Proteína Pós-Traducional , Transdução de Sinais , Sus scrofa , Toxoplasma/imunologia , Toxoplasmose/imunologia , Toxoplasmose/metabolismoRESUMO
Objective: The aim of the study is to investigate effects of loneliness on individual's mental health and the mediating effects of intolerance of uncertainty and sleep quality in the post Coronavirus-19 period, especially for the young people. Methods: The questionnaires used in this study include UCLA loneliness scale (UCLA-3), the Pittsburgh Sleep Quality Index (PSQI), intolerance for uncertainty (IU) and the Chinese version of DASS-21. A total number of 289 subjects were recruited in the study, which includes 209 females (72.3%), 80 males (27.7%); and 212 students (73.4%), 77 working staffs (26.6%). Results: The results showed that: (1) people have high levels of loneliness, anxiety, depression and stress, and poor sleep quality; (2) the mediating effect of intolerance for uncertainty in the relationship of loneliness and mental health is significant (effect size = 0.178, 95% CI confidence interval: [0.115, 0.241]), and the mediating effects of sleep quality in the relationship between loneliness and mental health is significant (effect size = 0.127, 95% CI confidence interval: [0.017, 0.239]). Conclusion: Loneliness invokes a stronger self-concerned inadaptability to threat response and may lead to more mental diseases through more serious intolerance for uncertainty and insomnia.
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The Freudian theory of conversion suggested that the major symptoms of functional neurological disorders (FNDs) are due to internal conflicts at motivation, especially at the sex drive or libido. FND patients might behave properly at rewarding situations, but they do not know how to behave at aversive situations. Sex drive is the major source of dopamine (DA) release in the limbic area; however, the neural mechanism involved in FND is not clear. Dopaminergic (DAergic) neurons have been shown to play a key role in processing motivation-related information. Recently, DAergic neurons are found to be involved in reward-related prediction error, as well as the prediction of aversive information. Therefore, it is suggested that DA might change the rewarding reactions to aversive reactions at internal conflicts of FND. So DAergic neurons in the limbic areas might induce two major motivational functions: reward and aversion at internal conflicts. This article reviewed the recent advances on studies about DAergic neurons involved in aversive stimulus processing at internal conflicts and summarizes several neural pathways, including four limbic system brain regions, which are involved in the processing of aversion. Then the article discussed the vital function of these neural circuits in addictive behavior, depression treatment, and FNDs. In all, this review provided a prospect for future research on the aversion function of limbic system DA neurons and the therapy of FNDs.
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Gerbils are susceptible to dietary cholesterol and prone to hypercholesterolemia and nonalcoholic fatty liver disease. The present study aimed to explore the role of sterol regulatory element binding protein (SREBP)2 and 3hydroxy3methylglutaryl CoA reductase (HMGCR) in hypercholesterolemia susceptibility in gerbils. Male gerbils were fed the normal diet or a highfat diet (HFD) for 2 weeks, or the HFD for 2 weeks followed with the normal diet for an additional 2 weeks. Serum lipid levels and hepatic fat deposition were measured, and mRNA and protein levels of SREBP2 and HMGCR were evaluated by quantitative polymerase chain reaction and Western blotting. In addition, the role of SREBP2 function in cholesterol synthesis from the gerbil primary hepatic cells was also investigated by modulation of SERBP2 expression via the transfection of SREBP2 overexpression and knockdown plasmids, respectively. The data demonstrated that the total cholesterol and lowdensity lipoprotein cholesterol levels in the gerbil serum samples were rapidly and significantly elevated in response to HFD. In addition, the effect of the HFD was rapidly attenuated in the gerbils following a return to the normal diet. HMGCR expression and activation were not altered by dietary cholesterol consumption in the livers from the gerbils in model or recovery groups. HMGCR expression and activation were effectively regulated in cultured hepatic cells from the gerbils. These results indicated that the activation of SREBP2 to HMGCR was not terminated in gerbil livers during cholesterol intake. Therefore, stable SREBP2 expression contributes to the susceptibility of gerbils to hypercholesterolemia.
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Expressão Gênica , Gerbillinae/genética , Hipercolesterolemia/veterinária , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Animais , Colesterol/sangue , Colesterol/metabolismo , Dieta Hiperlipídica/efeitos adversos , Regulação da Expressão Gênica , Gerbillinae/sangue , Gerbillinae/metabolismo , Hidroximetilglutaril-CoA Redutases/genética , Hidroximetilglutaril-CoA Redutases/metabolismo , Hipercolesterolemia/sangue , Hipercolesterolemia/etiologia , Hipercolesterolemia/genética , Metabolismo dos Lipídeos , Lipídeos/sangue , Fígado/metabolismo , Fígado/patologia , Masculino , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismoRESUMO
Deformities in the Circle of Willis (CoW) can significantly increase the risk of cerebrovascular disease in humans. However, the molecular mechanisms underlying these deformities have not been understood. Based on our previous studies, variations in the CoW of gerbils are hereditary. A normal CoW is observed in approximately 60% of gerbils, a percentage that also applies to humans. Thus, gerbil is an ideal experimental model for studying variations in the CoW. To study the mechanisms underlying these variations, we selected genes associated with different types of the CoW using suppression subtractive hybridization (SSH). After evaluating the efficiency of SSH using quantitative real-time polymerase chain reaction (qPCR) on subtracted and unsubtracted cDNA and Southern blotting on SSH PCR products, 12 SSH libraries were established. We identified 4 genes (CST3, GNAS, GPx4 and PFN2) associated with variations in the CoW. These genes were identified with qPCR and Western blotting using 70 expressed sequence tags from the SSH libraries. Cloning and sequencing allowed us to demonstrate that the 4 genes were closely related to mouse genes. We may assume that these 4 genes play an important role in the development of variations in the CoW. This study provides a foundation for further research of genes related to development of variations in the CoW and the mechanisms of dysmorphosis of cerebral vessels.
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Círculo Arterial do Cérebro/anormalidades , Animais , Cistatina C/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Estudos de Associação Genética , Gerbillinae , Glutationa Peroxidase/genética , Dados de Sequência Molecular , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Profilinas/genética , Técnicas de Hibridização SubtrativaRESUMO
Due to the increasing concern of using smallpox virus as biological weapons for terrorist attack, there is renewed interest in studying the pathogenesis of human smallpox and development of new therapies. Animal models are highly demanded for efficacy and safety examination of new vaccines and therapeutic drugs. Here, we demonstrated that both wild type and immunodeficient rats infected with an engineered vaccinia virus carrying Firefly luciferase reporter gene (rTV-Fluc) could recapitulate infectious and clinical features of human smallpox. Vaccinia viral infection in wild type Sprague-Dawley (SD) rats displayed a diffusible pattern in various organs, including liver, head and limbs. The intensity of bioluminescence generated from rTV-Fluc correlated well with viral loads in tissues. Moreover, neutralizing antibodies had a protective effect against virus reinfection. The recombination activating gene 2 (Rag2) knockout rats generated by transcription activator-like effector nucleases (TALENs) technology were further used to examine the infectivity of the rTV-Fluc in immunodeficient populations. Here we demonstrated that Rag2-/- rats were more susceptible to rTV-Fluc than SD rats with a slower virus clearance rate. Therefore, the rTV-Fluc/SD rats and rTV-Fluc/Rag2-/- rats are suitable visualization models, which recapitulate wild type or immunodeficient populations respectively, for testing human smallpox vaccine and antiviral drugs.