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1.
Theranostics ; 11(16): 7640-7657, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335955

RESUMO

Background: Since primary prostate cancer (PCa) can advance to the life-threatening metastatic PCa, exploring the molecular mechanisms underlying PCa metastasis is crucial for developing the novel targeted preventive strategies for decreasing the mortality of PCa. RNA N6-methyladenosine (m6A) is an emerging regulatory mechanism for gene expression and its specific roles in PCa progression remains elusive. Methods: Western blotting, quantitative real-time PCR and immunohistochemical analyses were used to detect target gene expression in PCa cells in vitro and prostate tissues from patients. RNA immunoprecipitation was conducted to analyze the specific binding of mRNA to the target protein. Migration and invasion assays were used to assess the migratory capacities of cancer cells. The correlation between target gene expression and survival rate of PCa patients was analyzed based the TCGA database. Results: We found that total RNA N6-methyladenosine (m6A) modification levels were markedly upregulated in human PCa tissues due to increased expression of methyltransferase like 3 (METTL3). Further studies revealed that the migratory and invasive capacities of PCa cells were markedly suppressed upon METTL3 knockdown. Mechanistically, METTL3 mediates m6A modification of USP4 mRNA at A2696, and m6A reader protein YTHDF2 binds to and induces degradation of USP4 mRNA by recruiting RNA-binding protein HNRNPD to the mRNA. Decrease of USP4 fails to remove the ubiquitin group from ELAVL1 protein, resulting in a reduction of ELAVL1 protein. Lastly, downregulation of ELAVL1 in turn increases ARHGDIA expression, promoting migration and invasion of PCa cells. Conclusions: Our findings highlight the role of METTL3 in modulating invasion and metastasis of PCa cells, providing insight into promising therapeutic strategies for hindering PCa progressing to deadly metastases.


Assuntos
Metiltransferases/genética , Neoplasias da Próstata/metabolismo , Adenosina/análogos & derivados , Adenosina/genética , Adenosina/metabolismo , Movimento Celular/genética , Proliferação de Células/genética , Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/genética , Inativação Gênica/fisiologia , Humanos , Masculino , Metiltransferases/metabolismo , Invasividade Neoplásica/genética , Metástase Neoplásica/genética , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/genética , RNA Mensageiro/genética , Proteínas de Ligação a RNA/metabolismo , Proteases Específicas de Ubiquitina/genética
2.
Sci Total Environ ; 794: 148732, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34323745

RESUMO

It has been reported that microcystin-leucine-arginine (MC-LR) can enter into the brain and demonstrate neurotoxicity resulting in learning and memory deficits. While, there is still a lack of clear understanding of the related molecular mechanisms. In this study, we observed ß-amyloid (Aß) accumulation and tau hyperphosphorylation (p-tau) at sites of Ser396 and Thr205 in mouse hippocampus and cortex, Alzheimer's disease (AD) like changes, after chronic exposure to MC-LR at different concentrations (1, 7.5, 15 and 30 µg/L) for 180 days. The hallmarks of AD are characterized by senile plaques and neurofibrillary tangles (NFT), with associated loss of neurons, resulting in cognitive impairment and dementia. Similarly, the production of Aß and tau hyperphosphorylation was also detected in HT-22 cells treated with MC-LR. In addition, MC-LR promoted increased expressions of BACE1 and PS1, but reduced mRNA expressions of ADAM family members both in vivo and in vitro, promoting the Aß production. Moreover, we identified Akt/GSK-3ß signal pathway mediated the Aß and p-tau accumulation, bringing about Alzheimer's disease-like changes. Furthermore, microglial cells were activated in those mice exposed to MC-LR. Inflammatory cytokines were also found being activated to release in vitro. In conclusion, this study could provide a clue for MC-LR-induced neurotoxicity, which gave insights into the environmental risks of Alzheimer's disease.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Proteínas tau , Secretases da Proteína Precursora do Amiloide , Animais , Ácido Aspártico Endopeptidases , Quinase 3 da Glicogênio Sintase , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Proteínas tau/metabolismo
3.
J Colloid Interface Sci ; 600: 449-462, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34023706

RESUMO

Peroxymonosulfate (PMS) activation by heterogeneous transition metal oxides is an effective approach for treating emerging pollutants in water. However, the low PMS activation efficiency associated with the valency conversion rate of transition metals has been a major challenge to sulfate radical-based oxidation. In this work, manganese cobaltate (MnCo2O4) nanoparticles anchored on graphitic carbon nitride (g-C3N4) flakes (MnCo2O4/g-C3N4) were successfully prepared and showed high PMS activation efficiency under visible (Vis) light. The obtained catalysts degraded 96.1% of the tetracycline hydrochloride (TCH) through the synergistic effect of PMS and photocatalysis. The reaction rate constant (0.2505 min-1) was 5.3 and 1.8 times higher in the MnCo2O4/g-C3N4/PMS/Vis system than in the pristine g-C3N4 (0.0471 min-1) and MnCo2O4 (0.1435 min-1) systems, respectively. The characterization results verified that g-C3N4, which functions as the electron donor in the photocatalytic heterojunction system, could transmit numerous photogenerated electrons to MnCo2O4, thereby increasing the cyclability of divalent-trivalent metal ions. The composites also showed good stability, cycling capability, and cation/anion tolerance. Tentative degradation mechanism and reaction pathways were proposed based on the reactive species and degradation products.


Assuntos
Manganês , Tetraciclina , Grafite , Luz , Compostos de Nitrogênio , Peróxidos
4.
J Hazard Mater ; 417: 126092, 2021 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-34015712

RESUMO

There is a growing concern regarding the toxic effects of nanoplastics (NPs) on aquatic and marine organism, while relatively few studies about their toxicity evaluation on mammals are conducted. In the present study, we observed accumulation of polystyrene NPs (PS NPs) in mice spleen, lung, kidney, small intestine, large intestine, testis, and brain after oral exposure to PS NPs (~100 nm, 10 mg/mL, 100 µL) for 28 days, and NPs were identified to induce cell apoptosis, inflammation, and structure disorder in these tissues. We also found that PS NPs could bring about hematological system injury and lipid metabolism disorder. Further in vitro studies identified that PS NPs could be absorbed by the intestinal epithelial Caco-2 cells by macropinocytosis and clathrin-mediated endocytosis, and induced disruption of tight junction between Caco-2 cells. Moreover, we found that it was easier for PS-NH2 and PS-COOH to enter into Caco-2 cells, which may be associated with observed stronger toxicity of PS-NH2 and PS-COOH NPs. In summary, this study demonstrated that NPs exposure brings about toxic effects to mice. This study could provide new insights regarding the distribution of NPs in humans, and helps us to evaluate the potential physiological risks of NPs to human beings.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Animais , Células CACO-2 , Humanos , Camundongos , Microplásticos , Nanopartículas/toxicidade , Poliestirenos/toxicidade
5.
Int J Hematol ; 114(2): 189-198, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33893987

RESUMO

Vascular endothelial growth factor affects the invasiveness of solid tumors by regulating angiogenesis. However, it is not clear whether VEGF could be used to predict the prognosis of DLBCL in the era of rituximab-based immunotherapy. We conducted a retrospective study to explore response to therapy and the prognostic value of VEGF on DLBCL in the rituximab era. The subjects were 65 patients with a histological diagnosis of DLBCL from the Affiliated Hospital of Xuzhou Medical University. Kaplan-Meier analysis was performed to estimate the cumulative survival rate of patients with different VEGF and IPI levels, and comparisons between groups were made using the log-rank test. DLBCL patients with elevated VEGF were more likely to have extranodal involvement, advanced stage, Myc/Bcl-2 double expression, and a higher Ki-67 score. Elevated VEGF was associated with poor therapeutic response and survival. When patients were divided into low, low-intermediate, high-intermediate and high-risk groups using the V-IPI model based on VEGF and IPI, PFS rates were 94.4, 74.1, 40.6 and 14.8%, respectively. This model better identified low-risk patients than IPI (85.9, 88.9, 37 and 7.8%). Our results demonstrate that VEGF predicts therapeutic response in DLBCL and the V-IPI model accurately predicts PFS of low-risk DLBCL in the rituximab era.


Assuntos
Biomarcadores Tumorais , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Humanos , Imuno-Histoquímica , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/etiologia , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Prognóstico , Rituximab/administração & dosagem , Rituximab/uso terapêutico , Análise de Sobrevida , Resultado do Tratamento
6.
J Colloid Interface Sci ; 597: 269-277, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33872883

RESUMO

Charge states at the catalytic interface can intensely alter the charge transfer mechanism and thus the oxygen reduction performance. Two symmetric cobalt porphyrins with electron deficient 2,1,3-benzothiadiazole (BTD) and electron-donating propeller-like triphenylamine (TPA) derivatives have been designed firstly, to rationally generate intramolecular partial charges, and secondly, to utilize the more exposed molecular orbitals on TPA for enhancing the charge transfer kinetics. The catalytic performance of the two electrocatalysts was examined for oxygen reduction reactions (ORR) in acidic electrolyte. It was found that BCP1/C with two BTD groups showed greater reduction potential but less limiting current density as compared to BCP2/C bearing BTD-TPA units. The reduced potential of BCP2/C was proposed to the introduction of the electron-donating ability of TPA, which may decrease the adsorption affinity of oxygen to the cobalt center. Both dipole-induced partial charge effect and the more exposed cation orbitals of the 3D structural TPA were proposed to contribute to the increased response current of BCP2/C. In addition, BCP2/C attained more than 80% of H2O2 generation in acidic solution, which may also relate to the structural effect. These findings may provide new insight into the structural design of organic electrocatalysts and deep understanding on the interfacial charge transfer mechanism for ORR.

7.
Chem Commun (Camb) ; 57(24): 2970-2981, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33624635

RESUMO

Lanthanide-doped inorganic nanocrystals, possessing superior luminescence performance and photochemical stability, have attracted considerable attention due to their promising biological applications such as in bioimaging, biodetection, biotherapeutics and temperature sensing. Great progress has been made in achieving distinct and tailored optical properties for these functional nanocrystals in the past few decades. In this feature article, we summarize our recent advances in the realization of desirable and tunable luminescence for lanthanide-doped inorganic nanocrystals through local structure engineering that includes two main strategies, namely, externally morphological architecture design and intrinsically crystal structure regulation. As for the externally morphological architecture design, distinct optical performance achieved in lanthanide-doped nanocrystals with varied morphologies like core-shell, hollow and ultrasmall nanoarchitectures is summarized. With regard to the intrinsically crystal structure regulation, the tunable upconversion luminescence intensity and red-to-green ratio of Er3+ for Yb3+/Er3+-doped nanocrystals and the consequent biodegradable nanocrystals are discussed, with an emphasis on the origin underlying the crystal-structure-dependent upconversion luminescence. Multifarious biological applications, including heterogeneous biodetection based on core-shell nanocrystals, homogeneous biodetection based on ultrasmall nanocrystals, superior nanothermometer based on hollow nanocrystals and in vivo bioimaging based on biodegradable nanocrystals, are briefly reviewed. Current challenges and future opportunities for lanthanide-doped inorganic nanocrystals for biological applications are also provided in the end.


Assuntos
Elementos da Série dos Lantanídeos/química , Substâncias Luminescentes/química , Nanopartículas/química , Animais , Técnicas Biossensoriais/métodos , Neoplasias/diagnóstico por imagem , Imagem Óptica , Tamanho da Partícula , alfa-Fetoproteínas/análise
8.
Chemosphere ; 264(Pt 1): 128440, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33002802

RESUMO

Microcystin-leucine-arginine (MC-LR) has been identified to be a hazardous material to cause hepatotoxicity. In this study, mice were exposed to MC-LR dissolved in drinking water at doses of 1, 10, 20 and 30 µg/L for 90 and 180 days, respectively. We validated MC-LR accelerated spermatid exfoliation and caused large vacuoles in testes, reducing sperm count and increasing percentage of morphologically abnormal sperm. Furthermore, we found MC-LR induced the apical ectoplasmic specialization (ES) disassembly by disrupting F-actin organization. Further studies identified that downregulation of Palladin, the actin crosslinking protein, might be associated with disassembly of the apical ES in mice testis following MC-LR exposure. We also confirmed that MC-LR disrupted the interaction between Palladin and other actin-related proteins and thus impeded the F-actin organization. Additionally, we found that autophagy initiated by AMPK/ULK1 signaling pathway mediated the degradation of Palladin in Sertoli cells challenged with MC-LR. Following exposure to MC-LR, reduced PP2A activity and upregulated expression of LKB1 and CAMKK2 could activate AMPK. In conclusion, these results revealed MC-LR induced the degradation of Palladin via AMPK/ULK1-mediated autophagy, which might result in the apical ES disorder and spermatid exfoliation from spermatogenic epithelium. Our work may provide a new perspective to understand MC-LR-induced male infertility.


Assuntos
Arginina , Microcistinas , Animais , Leucina , Masculino , Camundongos , Microcistinas/toxicidade , Células de Sertoli , Testículo
9.
Magn Reson Med ; 85(2): 953-961, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32783233

RESUMO

PURPOSE: To compare cortical gray matter oxygen extraction fraction (OEF) estimated from 2 MRI methods: (1) the quantitative susceptibility mapping (QSM) plus quantitative blood oxygen level dependent imaging (qBOLD) (QSM+qBOLD or QQ), and (2) the dual-gas calibrated-BOLD (DGCB) in healthy subjects; and to investigate the validity of iso-cerebral metabolic rate of oxygen consumption assumption during hypercapnia using QQ. METHODS: In 10 healthy subjects, 3 tesla MRI including a multi-echo gradient echo sequence at baseline and hypercapnia for QQ, as well as an EPI dual-echo pseudo-continuous arterial spin labeling for DGCB, were performed under a hypercapnic and a hyperoxic condition. OEFs from QQ and DGCB were compared using region of interest analysis and paired t test. For QQ, cerebral metabolic rate of oxygen consumption = cerebral blood flow*OEF*arterial oxygen content was generated for both baseline and hypercapnia, which were compared. RESULTS: Average OEF in cortical gray matter across 10 subjects from QQ versus DGCB was 35.5 ± 6.7% versus 38.0 ± 9.1% (P = .49) at baseline and 20.7 ± 4.4% versus 28.4 ± 7.6% (P = .02) in hypercapnia: OEF in cortical gray matter was significantly reduced as measured in QQ (P < .01) and in DGCB (P < .01). Cerebral metabolic rate of oxygen consumption (in µmol O2 /min/100 g) was 168.2 ± 54.1 at baseline from DGCB and was 153.1 ± 33.8 at baseline and 126.4 ± 34.2 (P < .01) in hypercapnia from QQ. CONCLUSION: The differences in OEF obtained from QQ and DGCB are small and nonsignificant at baseline but are statistically significant during hypercapnia. In addition, QQ shows a cerebral metabolic rate of oxygen consumption decrease (17.4%) during hypercapnia.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular , Substância Cinzenta , Humanos , Oxigênio , Consumo de Oxigênio
10.
Phys Rev Lett ; 125(21): 210601, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33275022

RESUMO

The finite-time dynamics, apart from its fundamental importance in nonequilibrium thermodynamics, is of great significance in designing heat engine cycles. We build an experimental apparatus to test the predicted long-time 1/τ scaling of the irreversible entropy generation in the finite-time (τ) thermodynamic process by compressing dry air in a temperature-controlled water bath. We present the first direct experimental validation of the scaling, utilized in many finite-time thermodynamic models at the long-time regime. The experimental data also demonstrate a clear deviation from the scaling at the short-time regime. We show the optimal control scheme to minimize the irreversible entropy generation in finite-time process. Such optimization shall bring new insight to the practical design of heat engine cycles.

11.
Entropy (Basel) ; 22(9)2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-33286771

RESUMO

Heat engines used to output useful work have important practical significance, which, in general, operate between heat baths of infinite size and constant temperature. In this paper, we study the efficiency of a heat engine operating between two finite-size heat sources with initial temperature difference. The total output work of such heat engine is limited due to the finite heat capacity of the sources. We firstly investigate the effects of different heat capacity characteristics of the sources on the heat engine's efficiency at maximum work (EMW) in the quasi-static limit. Moreover, it is found that the efficiency of the engine operating in finite-time with maximum power of each cycle is achieved follows a simple universality as η=ηC/4+OηC2, where ηC is the Carnot efficiency determined by the initial temperature of the sources. Remarkably, when the heat capacity of the heat source is negative, such as the black holes, we show that the heat engine efficiency during the operation can surpass the Carnot efficiency determined by the initial temperature of the heat sources. It is further argued that the heat engine between two black holes with vanishing initial temperature difference can be driven by the energy fluctuation. The corresponding EMW is proved to be ηMW=2-2.

12.
Ann Glob Health ; 86(1): 128, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33102148

RESUMO

Background: COVID-19 first appeared in China in December 2019, with a high rate of infectivity and morbidity, which brought tremendous psychological pressure to healthcare workers. Purpose: To understand the psychological health status of healthcare workers during the COVID-19 outbreak and decline, and to provide a theoretical reference for the future establishment of a psychological crisis intervention system. Methods: Healthcare workers were recruited using convenience sampling and snowball sampling methods, and the electronic version of the SCL-90 scale and a sociodemographic questionnaire were administered. In the pretest, a total of 5018 responses were collected; after six weeks, random sampling was performed. The SCL-90 and measures of other epidemic-related problems were administered, with 1570 responses received; then, the final data analysis was performed. Results: After six weeks, the post-test GSI score; SCL-90 total score; and PST, PSDI, O-C, I-S, DEP, ANX, PHOB, PAR, PSY, and HOS scores were significantly lower than the corresponding pretest scores (p < 0.05). The results by occupational category showed that the scores of nursing staff decreased significantly for 12 indexes and that the scores of the doctors and other hospital staff also significantly decreased. There was a significant difference between the pretest (50.78 ± 28.18) and post-test (45.00 ± 28.49) scores for the degree of worry about the epidemic. Healthcare workers believed that the top three aspects of life affected by the epidemic were economic problems (816 people), interpersonal communication problems (731 people), and mental health (728 people). Conclusion: Over the course of the epidemic, the item scores generally declined significantly. Therefore, during an outbreak period, attention should be paid to psychological crisis interventions for healthcare workers; problems caused by psychological pressure, and even other psychological conditions, can be significantly alleviated to reduce the probability of subsequent health problems.


Assuntos
Ansiedade , Infecções por Coronavirus , Intervenção na Crise/métodos , Depressão , Pessoal de Saúde/psicologia , Pandemias , Pneumonia Viral , Estresse Psicológico , Adulto , Ansiedade/diagnóstico , Ansiedade/etiologia , Betacoronavirus , COVID-19 , China/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/psicologia , Depressão/diagnóstico , Depressão/etiologia , Feminino , Humanos , Masculino , Saúde Mental/estatística & dados numéricos , Estresse Ocupacional/classificação , Estresse Ocupacional/diagnóstico , Estresse Ocupacional/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/psicologia , Escalas de Graduação Psiquiátrica , SARS-CoV-2 , Estresse Psicológico/diagnóstico , Estresse Psicológico/etiologia
13.
Medicine (Baltimore) ; 99(43): e22789, 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33120794

RESUMO

RATIONALE: The advent of high-resolution genome arrays including array comparative genomic hybridization (aCGH) has enabled the detection of cryptic submicroscopic deletions flanking translocation breakpoints in up to 20% of the apparently "balanced" structural chromosomal rearrangements in hematological disorders. However, reports of submicroscopic deletions flanking the breakpoints of t(3;5)(q25;q35) are rare and the clinical significance of submicroscopic deletions in t(3;5) has not been explicitly identified. PATIENT CONCERNS: We present a 47-year-old man with acute myeloid leukemia. G-banding analysis identified t(3;5)(q25;q35). DIAGNOSIS: Array CGH-based detection initially confirmed only the deletion of chromosome 3. Further characterization using fluorescence in situ hybridization identified a cryptic submicroscopic deletion including 5' MLF1-3' NPM1 flanking the breakpoint on the derivative chromosome 3. INTERVENTIONS: The patient started "7+3" induction chemotherapy with cytosine arabinoside and daunorubicin, and subsequently received 2 cycles of high-dose intermittent acronym of cytosine arabinoside or cytarabine. OUTCOMES: The patient did not undergo complete remission and died from an infection due to neutropenia. LESSONS: Haploinsufficiency of NPM1 or other deleted genes, including SSR3, may be responsible for the phenotype of t(3;5)(q25;q35)-positive myeloid neoplasms with submicroscopic deletions.


Assuntos
Leucemia Mieloide Aguda/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bandeamento Cromossômico , Hibridização Genômica Comparativa , Humanos , Hibridização in Situ Fluorescente , Leucemia Mieloide Aguda/tratamento farmacológico , Masculino , Pessoa de Meia-Idade
14.
Magn Reson Med ; 84(6): 3271-3285, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32602975

RESUMO

PURPOSE: To use hyperoxia in combination with QSM to quantify microvascular oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen (CMRO2 ) in healthy subjects and to cross-validate results with those from hypercapnia QSM-OEF. METHODS: Ten healthy subjects were scanned on a 3T MRI scanner. At baseline normoxia and during hyperoxia (PetO2 = +300 mmHg), QSM data were acquired using a multi-echo gradient-echo (GRE) sequence, and cerebral blood flow data were acquired using a pseudocontinuous arterial spin labeling sequence. The OEF and CMRO2 maps were computed and compared with those from hypercapnia QSM-OEF, acquired in the same subjects, using correlation and Bland-Altman analysis in 16 vascular territories. RESULTS: Hyperoxia QSM-OEF produced physiologically reasonable OEF and CMRO2 values in all subjects (gray-matter region of interest average OEF = 0.42 ± 0.04, average CMRO2 = 181 ± 34 µmol O2 /min/100 g). When compared with hypercapnia QSM-OEF, Bland-Altman plots revealed small deviations (mean OEF difference = 0.015, mean CMRO2 difference = 4.9 µmol O2 /min/100 g, P < .05). Good and excellent correlations of regional OEF and CMRO2 were found for the two methods. In addition, hyperoxia had minimal impact on cerebral blood flow (average gray-matter cerebral blood flow was reduced by 7.5 ± 5.4%). CONCLUSIONS: Hyperoxia in combination with QSM is a robust approach to measure OEF. Compared with hypercapnia, hyperoxia is more comfortable and has minimal impact on cerebral blood flow.


Assuntos
Hiperóxia , Oxigênio , Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular , Substância Cinzenta , Humanos , Hiperóxia/diagnóstico por imagem , Imageamento por Ressonância Magnética , Consumo de Oxigênio
15.
Medicine (Baltimore) ; 99(15): e19694, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32282724

RESUMO

BACKGROUND: To evaluate the association between risperidone use and interleukin-6 (IL-6) levels by conducting a meta-analysis of controlled before-and-after studies. METHODS: Studies were identified through a systematic search of PubMed and Embase. The mean and standardized differences were extracted to calculate the standardized mean differences. IL-6 levels were compared in patients with schizophrenia before and after risperidone treatment. RESULTS: Ten studies were included in the final meta-analysis. The primary findings from our study suggest that there was a significant decrease in serum IL-6 levels after risperidone treatment (P = .021). A subgroup analysis revealed the sources of heterogeneity. The sensitivity analysis indicated that the results were stable, and no publication bias was observed. CONCLUSIONS: The present meta-analysis provides evidence that risperidone can significantly reduce IL-6 levels in schizophrenia. IL-6 is a potential biomarker of the pathophysiology and clinical processes of schizophrenia.


Assuntos
Antipsicóticos/uso terapêutico , Interleucina-6/sangue , Risperidona/uso terapêutico , Esquizofrenia/tratamento farmacológico , Adulto , Biomarcadores/sangue , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Esquizofrenia/metabolismo , Esquizofrenia/fisiopatologia , Sensibilidade e Especificidade
17.
Phys Rev E ; 101(1-1): 012106, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32069657

RESUMO

The aging process is a common phenomenon in engineering, biological, and physical systems. The hazard rate function, which characterizes the aging process, is a fundamental quantity in the disciplines of reliability, failure, and risk analysis. However, it is difficult to determine the entire hazard function accurately with limited observation data when the degradation mechanism is not fully understood. Inspired by the seminal work pioneered by Jaynes [Phys. Rev. 106, 620 (1956)PHRVAO0031-899X10.1103/PhysRev.106.620], this study develops an approach based on the principle of maximum entropy. In particular, the time-dependent hazard rate function can be established using limited observation data in a rational manner. It is shown that the developed approach is capable of constructing and interpreting many typical hazard rate curves observed in practice, such as the bathtub curve, the upside down bathtub, and so on. The developed approach is applied to model a classical single function system and a numerical example is used to demonstrate the method. In addition its extension to a more general multifunction system is presented. Depending on the interaction between different functions of the system, two cases, namely reducible and irreducible, are discussed in detail. A multifunction electrical system is used for demonstration.

18.
Magn Reson Med ; 83(1): 68-82, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31373088

RESUMO

PURPOSE: To compare regional oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen consumption (CMRO2 ) quantified from the microvascular quantitative susceptibility mapping (QSM) using a hypercapnic gas challenge with those measured by the dual-gas calibrated BOLD imaging (DGC-BOLD) in healthy subjects. METHODS: Ten healthy subjects were scanned using a 3T MR system. The QSM data were acquired with a multi-echo gradient-echo sequence at baseline and hypercapnia. Cerebral blood flow data were acquired using the pseudo-continuous arterial spin labeling technique. Baseline OEF and CMRO2 were calculated using QSM and cerebral blood flow measurements. The DGC-BOLD data were also collected under a hypercapnic and a hyperoxic condition to yield baseline OEF and CMRO2 . The QSM-OEF and CMRO2 maps were compared with DGC-BOLD OEF and CMRO2 maps using region of interest (vascular territories) analysis and Bland-Altman plots. RESULTS: Hypercapnia is a robust stimulus for mapping OEF in combination with QSM. Average OEF in 16 vascular territory regions of interest across 10 subjects was 0.40 ± 0.04 by QSM-OEF and 0.38 ± 0.09 by DGC-BOLD. The average CMRO2 was 176 ± 35 and 167 ± 53 µmol O2 /min/100g by QSM-OEF and DGC-BOLD, respectively. A Bland-Altman plot of regional OEF and CMRO2 in regions of interest revealed a statistically significant but small difference (OEF difference = 0.02, CMRO2 difference = 9 µmol O2 /min/100g, p < .05) between the 2 methods for the 10 healthy subjects. CONCLUSION: Hypercapnic challenge-assisted QSM-OEF is a feasible approach to quantify regional brain OEF and CMRO2 . Compared with DGC-BOLD, hypercapnia QSM-OEF results in smaller intersubject variability and requires only 1 gas challenge.


Assuntos
Mapeamento Encefálico , Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Consumo de Oxigênio , Adulto , Algoritmos , Calibragem , Simulação por Computador , Imagem Ecoplanar , Feminino , Substância Cinzenta/diagnóstico por imagem , Voluntários Saudáveis , Humanos , Hipercapnia/metabolismo , Hiperóxia/metabolismo , Masculino , Oxigênio/sangue , Reprodutibilidade dos Testes , Marcadores de Spin
19.
PeerJ ; 7: e7104, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31245178

RESUMO

Background: Wheat is one of the most important staple crops worldwide. Fusarium head blight (FHB) severely affects wheat yield and quality. A novel bread wheat mutant, ZK001, characterized as cleistogamic was isolated from a non-cleistogamous variety Yumai 18 (YM18) through static magnetic field mutagenesis. Cleistogamy is a promising strategy for controlling FHB. However, little is known about the mechanism of cleistogamy in wheat. Methods: We performed a FHB resistance test to identify the FHB infection rate of ZK001. We also measured the agronomic traits of ZK001 and the starch and total soluble sugar contents of lodicules in YM18 and ZK001. Finally, we performed comparative studies at the proteome level between YM18 and ZK001 based on the proteomic technique of isobaric tags for relative and absolute quantification. Results: The infection rate of ZK001 was lower than that of its wild-type and Aikang 58. The abnormal lodicules of ZK001 lost the ability to push the lemma and palea apart during the flowering stage. Proteome analysis showed that the main differentially abundant proteins (DAPs) were related to carbohydrate metabolism, protein transport, and calcium ion binding. These DAPs may work together to regulate cellular homeostasis, osmotic pressure and the development of lodicules. This hypothesis is supported by the analysis of starch, soluble sugar content in the lodicules as well as the results of Quantitative reverse transcription polymerase chain reaction. Conclusions: Proteomic analysis has provided comprehensive information that should be useful for further research on the lodicule development mechanism in wheat. The ZK001 mutant is optimal for studying flower development in wheat and could be very important for FHB resistant projects via conventional crossing.

20.
Spectrochim Acta A Mol Biomol Spectrosc ; 210: 372-380, 2019 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-30502725

RESUMO

Ganoderic Acids (GAs) are the major medicinal compounds in Ganoderma lucidum used as traditional Chinese medicine since ancient times. Ganoderic acid A (GAA) is the first discovered ganoderic acids reported in the literature, which is also one of most abundant triterpenoids of Ganoderma lucidum. Especially, GAA has been extensively investigated in recent decades for its positive medicinal activities. However, the vibrational properties of GAs have rarely been studied or reported. In this work, we focused on the typical GAA and studied the infrared (IR) and Raman spectra based on both experiments and DFT calculations. As such, we could not only achieve the assignments of the vibrational modes, but also from the IR and Raman spectra, we found that the spectral region from 1500 cm-1 to 1800 cm-1 is particularly useful for distinguishing different types of GAs. In addition, its dehydrogenated derivative ganoderenic acid A (GOA) was also studied, which could be identified due to its spectral feature of strong IR and Raman bands around 1620 cm-1. This work therefore may facilitate the application of IR and Raman spectroscopies in the inspection and quality control of Ganoderma lucidum.


Assuntos
Ácidos Heptanoicos/química , Lanosterol/análogos & derivados , Espectrofotometria Infravermelho/métodos , Análise Espectral Raman/métodos , Colestanos/química , Teoria da Densidade Funcional , Lanosterol/química , Estrutura Molecular , Reishi/química , Espectroscopia de Infravermelho com Transformada de Fourier , Vibração
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