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1.
Reprod Biol ; 24(2): 100893, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38754347

RESUMO

Metastasis is the hallmark of cancer that is responsible for the greatest number of cancer-related deaths. As a critical regulator of the Hippo pathway, the phosphorylation status of Yes-associated protein 1 (YAP1), mainly at S127, is critical for its oncogenic function. Herein, we aim to investigate the precise molecular mechanism between long noncoding RNA HOX transcript antisense RNA (HOTAIR) and YAP1 phosphorylation in regulating tumor migration and invasion. In this study, we showed that inhibition of HOTAIR significantly decreased the migration and invasion of cancer cells both in vitro and in vivo through elevating the phosphorylation level of YAP1 on serine 127, demonstrating a tumor suppressive role of YAP1 S127 phosphorylation. Through bisulfite sequencing PCR (BSP), we found that inhibition of HOTAIR dramatically increased Large Tumor Suppressor Kinase 1 (LATS1) expression by regulating LATS1 methylation via DNA methyltransferase 3ß (DNMT3B). In accordance with this observation, DNMT3B just only altered the distribution of YAP1 in the cytoplasm and the nucleus by inhibiting its phosphorylation, but did not change its total expression. Mechanistically, we discovered that HOTAIR suppressed YAP1 S127 phosphorylation by regulating the methylation of LATS1 via DNMT3B, the consequence of which is the translocation of YAP1 into the nucleus, reinforcing its coactivating transcriptional function, which in turn promotes the migration and invasion of cancer cells. Collectively, our data reveal that the phosphorylation of YAP1 S127 plays a vital role in the function of HOTAIR in tumorigenicity, and should be taken into consideration in future therapeutic strategies for cervical cancer.

2.
Eur Neurol ; : 1-11, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38657568

RESUMO

INTRODUCTION: Dementia is a neurodegenerative disease with insidious onset and progressive progression, of which the most common type is Alzheimer's disease (AD). Lithium, a trace element in the body, has neuroprotective properties. However, whether lithium can treat dementia or AD remains a highly controversial topic. Therefore, we conducted a meta-analysis. METHODS: A systematic literature review was conducted on PubMed, Embase, and Web of Science. Comparison of the effects of lithium on AD or dementia in terms of use, duration, and dosage, and meta-analysis to test whether lithium therapy is beneficial in ameliorating the onset of dementia or AD. Sensitivity analyses were performed using a stepwise exclusion method. The Newcastle-Ottawa Scale (NOS) was used to assess the quality of included studies. We determined the relative risk (RR) between patient groups using a random-effects model. RESULTS: A total of seven studies were included. The forest plot results showed that taking lithium therapy reduced the risk of AD (RR 0.59, 95% confidence interval [CI]: 0.44-0.78) and is also protective in reducing the risk of dementia (RR 0.66, 95% CI: 0.56-0.77). The duration of lithium therapy was able to affect dementia incidence (RR 0.70, 95% CI: 0.55-0.88); however, it is unclear how this effect might manifest in AD. It is also uncertain how many prescriptions for lithium treatment lower the chance of dementia development. CONCLUSION: The duration of treatment and the usage of lithium therapy seem to lower the risk of AD and postpone the onset of dementia.

3.
Apoptosis ; 2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38615304

RESUMO

Ferroptosis is a new discovered regulated cell death triggered by the ferrous ion (Fe2+)-dependent accumulation of lipid peroxides associated with cancer and many other diseases. The mechanism of ferroptosis includes oxidation systems (such as enzymatic oxidation and free radical oxidation) and antioxidant systems (such as GSH/GPX4, CoQ10/FSP1, BH4/GCH1 and VKORC1L1/VK). Among them, ferroptosis suppressor protein 1 (FSP1), as a crucial regulatory factor in the antioxidant system, has shown a crucial role in ferroptosis. FSP1 has been well validated to ferroptosis in three ways, and a variety of intracellular factors and drug molecules can alleviate ferroptosis via FSP1, which has been demonstrated to alter the sensitivity and effectiveness of cancer therapies, including chemotherapy, radiotherapy, targeted therapy and immunotherapy. This review aims to provide important frameworks that, bring the regulation of FSP1 mediated ferroptosis into cancer therapies on the basis of existing studies.

4.
Mol Ther Nucleic Acids ; 35(1): 102107, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38204916

RESUMO

[This retracts the article DOI: 10.1016/j.omtn.2019.10.048.].

5.
PLoS One ; 18(12): e0293977, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38055651

RESUMO

BACKGROUND: Although Alzheimer's disease (AD) mainly affects cognitive function, it is often accompanied by sleep disorders and psychobehavioral symptoms. These symptoms, including depression, agitation, and psychotic symptoms, are prominent hospitalization causes among patients with AD. Currently, relatively more research exists on light therapy for sleep disorders, while those on psychobehavioral symptoms are gradually increasing. However, no consensus exists on these results because of the vulnerability of light therapy to multiple factors, including light intensity and duration. Thus, further research investigating this aspect is warranted. OBJECTIVE: To evaluate the efficacy of light therapy in improving sleep disorders and psychobehavioural symptoms in patients with AD. METHODS: In this meta-analysis, relevant literature was searched in Embase, the Clinical Trials Registry, Web of Science, PubMed, and the Cochrane Library up to December 2022. Furthermore, a fixed-effects model was used for data analysis. RESULTS: Fifteen randomized controlled trials involving 598 patients with AD were included. In the case of sleep disorders, our meta-analysis revealed that light therapy significantly improved sleep efficiency (MD = -2.42, 95% CI = -3.37 to -1.48, p < 0.00001), increased interdaily stability (MD = -0.04, 95% CI = -0.05 to -0.03, p < 0.00001), and reduced intradaily variability (MD = -0.07, 95% CI = -0.10 to -0.05, p < 0.00001). With respect to psychotic behavior, light therapy was found to alleviate depression (MD = -2.55, 95% CI = -2.98 to -2.12, p < 0.00001) as well as reduce agitation (MD = -3.97, 95% CI = -5.09 to -2.84, p < 0.00001) and caregiver burden (MD = -3.57, 95% CI = -5.28 to -1.87, p < 0.00001). CONCLUSION: Light therapy leads to significant improvement in sleep and psychobehavioral symptoms and is associated with relatively fewer side effects in patients with AD, indicating its potential as a promising treatment option for AD.


Assuntos
Doença de Alzheimer , Transtornos do Sono-Vigília , Humanos , Doença de Alzheimer/tratamento farmacológico , Sono , Cognição , Transtornos do Sono-Vigília/complicações , Fototerapia
6.
Genes (Basel) ; 14(11)2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38003039

RESUMO

High temperatures are considered one of the most significant limitations to subtropical fishery production. Largemouth bass (Micropterus salmoides) is an economically important freshwater species grown in subtropical areas, which are extremely sensitive to heat stress (HS). However, comprehensive transcriptomic data for the livers of largemouth bass in response to HS are still lacking. In this study, a comparative transcriptomic analysis was performed to investigate the gene expression profiles of the livers of largemouth bass under HS treatment. As a result, 6114 significantly differentially expressed genes (DEGs), which included 2645 up-regulated and 3469 down-regulated genes, were identified in response to HS. Bioinformatics analyses demonstrated that the 'ECM-receptor interaction' pathway was one of the most dramatically changed pathways in response to HS, and eight DEGs assigned to this pathway were taken as hub genes. Furthermore, the expression of these eight hub genes was determined by quantitative reverse transcription PCR, and all of them showed a significant change at the transcriptional level, suggesting a crucial role of the 'ECM-receptor interaction' pathway in the response of largemouth bass to HS. These findings may improve our understanding of the molecular mechanisms underlying the response of largemouth bass to HS.


Assuntos
Bass , Transcriptoma , Animais , Transcriptoma/genética , Bass/genética , Bass/metabolismo , Temperatura , Perfilação da Expressão Gênica , Fígado/metabolismo
7.
Viruses ; 15(7)2023 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-37515210

RESUMO

The highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) often causes secondary bacterial infection in piglets, resulting in inflammatory lung injury and leading to high mortality rates and significant economic losses in the pig industry. Microvascular endothelial cells (MVECs) play a crucial role in the inflammatory response. Previous studies have shown that HP-PRRSV can infect porcine pulmonary MVECs and damage the endothelial glycocalyx. To further understand the role of pulmonary MVECs in the pathogenesis of HP-PRRSV and its secondary bacterial infection, in this study, cultured porcine pulmonary MVECs were stimulated with a HP-PRRSV HN strain and lipopolysaccharide (LPS). The changes in gene expression profiles were analyzed through transcriptome sequencing, and the differentially expressed genes were verified using qRT-PCR, Western blot, and ELISA. Furthermore, the effects on endothelial barrier function and regulation of neutrophil trans-endothelial migration were detected using the Transwell model. HP-PRRSV primarily induced differential expression of numerous genes associated with immune response, including IFIT2, IFIT3, VCAM1, ITGB4, and CCL5, whereas LPS triggered an inflammatory response involving IL6, IL16, CXCL8, CXCL14, and ITGA7. Compared to the individual effect of LPS, when given after HN-induced stimulation, it caused a greater number of changes in inflammatory molecules, such as VCAM1, IL1A, IL6, IL16, IL17D, CCL5, ITGAV, IGTB8, and TNFAIP3A, a more significant reduction in transendothelial electrical resistance, and higher increase in neutrophil transendothelial migration. In summary, these results suggest a synergistic effect of HP-PRRSV and LPS on the inflammatory response of porcine pulmonary MVECs. This study provides insights into the mechanism of severe lung injury caused by secondary bacterial infection following HP-PRRSV infection from the perspective of MVECs, emphasizing the vital role of pulmonary MVECs in HP-PRRSV infection.


Assuntos
Infecções Bacterianas , Lesão Pulmonar , Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Animais , Suínos , Lipopolissacarídeos , Células Endoteliais , Interleucina-16 , Interleucina-6
8.
Front Cell Infect Microbiol ; 13: 1161763, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37333851

RESUMO

Background and objectives: Disease severity and prognosis of coronavirus disease 2019 (COVID-19) disease with other viral infections can be affected by the oropharyngeal microbiome. However, limited research had been carried out to uncover how these diseases are differentially affected by the oropharyngeal microbiome of the patient. Here, we aimed to explore the characteristics of the oropharyngeal microbiota of COVID-19 patients and compare them with those of patients with similar symptoms. Methods: COVID-19 was diagnosed in patients through the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by quantitative reverse transcription polymerase chain reaction (RT-qPCR). Characterization of the oropharyngeal microbiome was performed by metatranscriptomic sequencing analyses of oropharyngeal swab specimens from 144 COVID-19 patients, 100 patients infected with other viruses, and 40 healthy volunteers. Results: The oropharyngeal microbiome diversity in patients with SARS-CoV-2 infection was different from that of patients with other infections. Prevotella and Aspergillus could play a role in the differentiation between patients with SARS-CoV-2 infection and patients with other infections. Prevotella could also influence the prognosis of COVID-19 through a mechanism that potentially involved the sphingolipid metabolism regulation pathway. Conclusion: The oropharyngeal microbiome characterization was different between SARS-CoV-2 infection and infections caused by other viruses. Prevotella could act as a biomarker for COVID-19 diagnosis and of host immune response evaluation in SARS-CoV-2 infection. In addition, the cross-talk among Prevotella, SARS-CoV-2, and sphingolipid metabolism pathways could provide a basis for the precise diagnosis, prevention, control, and treatment of COVID-19.


Assuntos
COVID-19 , Microbiota , Humanos , SARS-CoV-2/genética , Teste para COVID-19 , Prevotella/genética , Esfingolipídeos
9.
Opt Express ; 31(11): 17861-17877, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37381509

RESUMO

In large-scale water quality evaluation, traditional field-measured data lack spatial-temporal representativeness, and the role of conventional remote sensing parameters (SST, Chla, TSM, etc.) is controversial. By calculating and grading the hue angle of a water body, a Forel-Ule index (FUI) can be obtained, which provides a comprehensive statement of water condition. Using MODIS imagery, hue angles are extracted with better accuracy than the literature's method. It is found that FUI changes in the Bohai Sea have correlated consistently with water quality. The decreasing trend of non-excellent water quality areas in the Bohai Sea was highly correlated with FUI (R2 = 0.701) during the government-dominated land-based pollution reduction program (2012-2021). FUI can monitor and evaluate seawater quality.

10.
Brain Res Bull ; 199: 110660, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37149267

RESUMO

In ischemia-reperfusion stroke, microglia play a dual role in brain injury as well as brain repair, and promoting their switch from a pro-inflammatory M1 phenotype to an anti-inflammatory M2 phenotype is considered to be a potential therapeutic strategy. Docosahexaenoic acid (DHA) is an essential long-chain omega-3 polyunsaturated fatty acid that exhibits potent anti-inflammatory properties in the acute phase of ischemic stroke, but its effect on microglia polarization is unknown. Thus, the objective of this study was to investigate the neuroprotective effects of DHA on rat brain following ischemia-reperfusion injury, and to investigate the mechanism by which DHA regulates microglia polarization. We administered DHA 5 mg/kg intraperitoneally daily for 3 d following a transient middle cerebral artery occlusion reperfusion model in rats. The protective effects of DHA on cerebral ischemia-reperfusion injury were detected by TTC staining, HE staining, Nissler staining, and TUNEL staining. Quantitative real-time PCR, immunofluorescence, western blot, and enzyme-linked immunosorbent assay were used to detect the expression of M1 and M2 microglia-associated markers and PPARγ-mediated ERK/AKT signaling pathway proteins. We found that DHA significantly improved brain injury by decreasing the expression of the M1 phenotypic marker (iNOS, CD16) and increasing the expression of the M2 phenotypic marker (Arg-1, CD206). DHA also increased the expression of peroxisome proliferator-activated receptor gamma (PPARγ) mRNA and protein, increased the expression of the pathway protein AKT, and decreased the expression of ERK1/2. In addition, DHA promoted the expression of anti-inflammatory factor IL-10 and decreased the expression of pro-inflammatory factors TNF-α and IL-1ß. However, the PPARγ antagonist GW9662 greatly blocked these beneficial effects. These results suggest that DHA may activate PPARγ to inhibit ERK and activate AKT signaling pathways to regulate microglia polarization, thereby reducing neuroinflammation and promoting neurological recovery to alleviate cerebral ischemia-reperfusion injury.


Assuntos
Lesões Encefálicas , Isquemia Encefálica , Traumatismo por Reperfusão , Ratos , Animais , Microglia/metabolismo , PPAR gama/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ácidos Docosa-Hexaenoicos/farmacologia , Ácidos Docosa-Hexaenoicos/metabolismo , Sistema de Sinalização das MAP Quinases , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Lesões Encefálicas/metabolismo , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Fenótipo
11.
Cancer Lett ; 557: 216075, 2023 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-36736530

RESUMO

N6-methyladenosine (m6A) RNA methylation and its associated RNA-binding protein insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) are involved in tumor initiation and progression. Here, we explored the biological function and clinical significance of IGF2BP1 in intrahepatic cholangiocarcinoma (iCCA). We found that IGF2BP1 expression was upregulated by H3K27 acetylation enrichment of its promoter, which positively correlated with poor clinicopathological characteristics and survival. Gain- and loss-of-function experiments showed that IGF2BP1 overexpression (knockdown) enhanced (attenuated) iCCA growth and metastasis in vitro and in vivo. Mechanistically, IGF2BP1 not only regulated the c-Myc/p16 axis to promote iCCA growth and inhibit senescence, but also activated the ZIC2/PAK4/AKT/MMP2 axis to induce tumor metastasis. More importantly, BTYNB, a recently identified IGF2BP1 inhibitor, exerted promising anti-tumor efficacy in a patient-derived xenograft (PDX) model, and IGF2BP1 conditional knockout (cKO) reduced the tumor burden. These results demonstrate the crucial role of IGF2BP1 in iCCA progression via m6A-dependent modification, highlighting IGF2BP1 as a potential therapeutic target in iCCA.


Assuntos
Colangiocarcinoma , Humanos , Linhagem Celular Tumoral , Colangiocarcinoma/patologia , Quinases Ativadas por p21
12.
J Phys Chem A ; 127(3): 799-816, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36648878

RESUMO

Recent high-level theoretical calculations predict a mild temperature dependence for HO2 + HO2 inconsistent with state-of-the-art experimental determinations that upheld the stronger temperature dependence observed in early experiments. Via MultiScale Informatics analysis of the theoretical and experimental data, we identified an alternative interpretation of the raw experimental data that uses HO2 + HO2 rate constants nearly identical to theoretical predictions─implying that the theoretical and experimental data are actually consistent, at least when considering the raw data from experimental studies. Similar analyses of typical signals from low-temperature experiments indicate that an HOOOOH intermediate─identified by recent theory but absent from earlier interpretations─yields modest effects that are smaller than, but may have contributed to, the scatter in data among different experiments. More generally, the findings demonstrate that modern chemical theories and experiments have progressed to a point where meaningful comparison requires joint consideration of their data simultaneously.

13.
Nurse Educ Today ; 120: 105630, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36410081

RESUMO

BACKGROUND: Effective communication is essential for nursing students to provide safe patient care. Many communication consensuses focus on physician-associated communication rather than nurses' interpersonal communication. However, studies on developing a systematic and comprehensive communication knowledge system for nursing students are scarce. OBJECTIVES: To explore the teaching content and teaching framework of nurses' interpersonal communication, construct a systematic and scientific knowledge system for interpersonal communication among nursing students and provide a theoretical basis for the training of nurses on interpersonal communication. METHODS: Based on the literature review and comparative research, this study explored the theoretical basis and basic principles of constructing an interpersonal communication knowledge system for nurses. Moreover, a correspondence questionnaire on nurses' interpersonal communication knowledge systems was initially constructed to clarify the related teaching content and structure. Finally, the Delphi method was used to establish the index of the nurses' interpersonal communication knowledge system according to the principle of expert selection and inclusion criteria. RESULTS: The Delphi method included 26 experts from nursing education, clinical nursing, nursing management and other fields for consultation. The effective response rate of the letter inquiry was 96.3 % in the first round and 100 % in the second round. The judgment basis, familiarity and authority coefficient of expert consultation were 0.907, 0.862 and 0.884, respectively. In the two rounds of inquiry, the coordination coefficients of the total questionnaire were 0.228 and 0.302, which was statistically significant (P < 0.001). Thereafter, a wheeled model of nurses' interpersonal communication knowledge system with 3 primary indicators, 13 secondary indicators and 58 tertiary indicators was constructed, which included professional ethics and attitude, communication knowledge and communication skills. CONCLUSION: Literature and comparative research methods along with Delphi expert consultation were used to construct a scientific and systematic knowledge system of nurses' interpersonal communication. The research methods were feasible, and the results were scientific and reliable, thereby providing a basis for the education of nurses' interpersonal communication among nurses and the compilation of related teaching materials in China and globally. Furthermore, special attention should be paid to the comprehensive cultivation of nursing students' professional ethics and attitude, communication knowledge and communication skills.


Assuntos
Educação em Enfermagem , Estudantes de Enfermagem , Humanos , Técnica Delphi , Comunicação , Inquéritos e Questionários
14.
Oncol Rep ; 48(6)2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36281949

RESUMO

The occurrence of tumors is associated with the upregulation or downregulation of certain genes. The identification of novel tumor therapies has revealed that regulation of tumor cell death can either promote or suppress the occurrence and development of tumors. Iron­dependent lipid free oxygen radical accumulation causes tumor cells to die by ferroptosis, a form of regulated cell death. Multiple mechanisms mediate this mode of cell death, including redox homeostasis, iron metabolism, mitochondrial activity, breakdown of amino acids, lipids and sugars and epigenetic regulatory and disease­associated signaling pathways. The present review discussed epigenetic mechanism of ferroptosis with the aim of providing novel insight for optimization of the effects of antitumor therapy.


Assuntos
Ferroptose , Neoplasias , Humanos , Ferroptose/genética , Espécies Reativas de Oxigênio/metabolismo , Epigênese Genética , Neoplasias/genética , Ferro/metabolismo , Aminoácidos/metabolismo , Açúcares
15.
J Phys Chem A ; 126(44): 8305-8314, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36300359

RESUMO

The multi-structural approximation with torsional anharmonicity (MS-T) method and its variants have been widely used for calculating conformational-rovibrational partition functions of large molecules. The present work aimed to propose a systematic method to assess and explain the performance of various variants of the MS-T method. First, we proposed the simplest variant MS-T(2NN) (two nearest neighborhood torsions are coupled) and systematically validated it for large alkanes n-CnH2n+2 (n = 6-10) and their transition states of hydrogen abstraction reactions. Second, we proposed a metric-based method to explain the underlying reason for the good performance of MS-T(2NN)─it includes the torsional conformers that have dominant contributions to the partition function calculations. These conformers are closer to the lowest-energy conformer in the space of dihedral and energy metrics. Third, the same observation and explanation apply to the other two variants, MS-2DT (any two torsions are coupled) and MS-3DT (any three torsional are coupled), which contain increasingly more torsional conformers than MS-T(2NN) but are subsets of the complete set of torsional conformers considered by the MS-T method. Overall, the present method provides a mathematically rigorous and computationally effective diagnosis tool to assess various MS-T methods dealing with the torsional anharmonicity of large molecules in the partition function calculation.


Assuntos
Hidrogênio , Termodinâmica , Conformação Molecular , Hidrogênio/química
16.
Comput Math Methods Med ; 2022: 4676968, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36035292

RESUMO

In order to scientifically explore the effective path of strength quality training of basketball players and improve the effect of strength quality training of basketball players, this paper takes young basketball players as the research object and comprehensively observes the changes and improvement of strength quality by building a strength training monitoring system for basketball players. On this basis, it is proposed to integrate blood flow restriction and basketball players' special strength training. Through the comparison with the traditional resistance strength training method, it is found that after 8 weeks of experimental comparison, the athletes' strength quality test indicators show that the average 3RM of the experimental group 1 bench press is 65.2 kg, the experimental group 2 is 65.7 kg, and the experimental group 3 is 72.2 kg. The average performance of the traditional control group was 55.4 kg. Compared with the traditional group, the average performance of the three experimental groups in bench press was significantly improved, which also verified the feasibility of this method in strength quality training.


Assuntos
Basquetebol , Treinamento Resistido , Adolescente , Atletas , Terapia por Exercício , Humanos , Força Muscular
17.
Faraday Discuss ; 238(0): 355-379, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-35866720

RESUMO

In 1922, Lindemann proposed the now-well-known mechanism for pressure-dependent rate constants for unimolecular reactions: reactant molecules with sufficiently high energies dissociate more quickly than collisions can reestablish the Boltzmann distribution of the internal energies of the molecule during its dissociation at low pressures - yielding pressure-dependent rate constants for unimolecular reactions due to the preferential depletion of the high energy states capable of dissociation. In the last century, incredible progress has been made in achieving a far greater understanding of and quantitative predictions for unimolecular and association reactions. In the modern era, pressure-dependent phenomenological rate constants are now nearly universally used to describe the rates of unimolecular and associative reactions in phenomenological kinetic modeling. However, there is a second, more indirect, implication of Lindemann's mechanism that relates to how these dissociation-induced non-equilibrium distributions impact bimolecular reactions, including non-associative bimolecular reactions - which are generally not considered to have pressure-dependent rate constants. Yet, as we show herein, the same high energy states depleted due to dissociation would otherwise react most rapidly in high-activation-energy bimolecular reactions - yielding a mechanism for pressure-dependent rate constants for bimolecular reactions (including non-associative reactions). Here, we present results from a case study for CH2O dissociation, isomerization, and bimolecular reaction with O2 to explore this question. Results from our master equation calculations indicate that the effect of dissociation-induced non-equilibrium distributions on bimolecular reactions can be substantial - even when chemical timescales are well separated from internal energy relaxational timescales (i.e. when the traditional rate constant description would be thought to apply). This effect is found to be more pronounced - and more complex - for bimolecular reactions involving molecular entities whose chemical timescales are merged with the internal energy relaxational timescales. Finally, we present some ideas for discussion regarding what should be considered as "chemical species" in phenomenological kinetic models.

18.
Animals (Basel) ; 12(12)2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35739875

RESUMO

Enterocytozoon bieneusi is the most prevalent microsporidian species that can cause zoonotic diseases in humans and animals. Despite receiving increasing attention in relation to domestic animals, there has been limited information on the infection burden of E. bieneusi in cervids. Altogether, 215 fecal samples collected from four deer species in Beijing, China were examined by nested- Polymerase Chain Reaction (PCR)targeting the internal transcribed spacer (ITS) region. The overall prevalence of E. bieneusi in deer was 21.9% (47/215), with 30.0% (24/80) in Pere David's deer, 27.3% (15/55) in fallow deer, 12.5% (5/40) in sika deer, and 7.5% (3/40) in Chinese water deer. Thirteen E. bieneusi genotypes were identified, including six known (HLJD-V, MWC_d1, BEB6, CGC2, JLD-XV, and HND-I) and seven novel genotypes (BJED-I to BJED-V, BJFD, and BJCWD). A phylogenetic analysis showed that 38.3% of the isolates belonged to zoonotic Group 1. In addition, E. bieneusi infection was first detected in fallow deer and Chinese water deer, which could act as potential zoonotic reservoirs. Our findings suggest that E. bieneusi circulates in deer and might be of importance to public health.

19.
Chem Commun (Camb) ; 57(18): 2233-2244, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33594392

RESUMO

Catalytic combustion technology is an exciting prospect for the removal of pollutants, especially in the field of transportation. Applying zeolites in fuel combustion has gained increasing importance in heterogeneous catalysis arising from their properties such as economical practicability and high activity. However, compared with the extensively investigated homogeneous combustion, few studies have been reported to explore the catalytic combustion of large-molecule fuels, especially for the catalytic combustion of biodiesel surrogate fuels. The purpose of this feature article is to describe the catalytic combustion of methyl butanoate (one of the biodiesel surrogate fuels) over unmodified HZSM-5 zeolites with a particular focus on the catalytic reaction mechanism. Experiments and theoretical calculations were considered here to help explain the proposed catalytic mechanism. This paper can provide new insights into the catalytic mechanism of biodiesel fuels that will guide the improvement of combustion efficiency in internal combustion engines and in the control of pollutant emissions.

20.
Acta Biochim Biophys Sin (Shanghai) ; 52(11): 1247-1256, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33166992

RESUMO

Intrahepatic cholangiocarcinoma (ICC) arises from cholangiocytes in the intrahepatic bile duct and is the second most common type of liver cancer. The overexpression of COUP-TFII has been observed in several types of malignancies. However, its role in ICC progression remains unclear. In this study, we found that the protein level of COUP-TFII was increased, but the mRNA level was unchanged in ICC tissues. High protein expression was positively associated with tumor size, lymph node metastasis, and poor prognosis in ICC patients. Furthermore, the overexpression of COUP-TFII promoted the proliferation, migration, and invasion of ICC cells in vitro and enhanced tumor growth and metastasis in nude mouse models. Mechanistic studies revealed that COUP-TFII induced epithelial-to-mesenchymal transition in ICC cells by upregulating Snail expression. Moreover, the activation of PI3K/AKT signaling led to the upregulation of COUP-TFII protein expression in ICC. Together, these findings indicate that COUP-TFII promotes epithelial-to-mesenchymal transition and metastasis in ICC and suggest that this protein is a potential target for adjuvant therapy for these patients.


Assuntos
Neoplasias dos Ductos Biliares/genética , Fator II de Transcrição COUP/genética , Fator II de Transcrição COUP/metabolismo , Colangiocarcinoma/genética , Transição Epitelial-Mesenquimal/genética , Fatores de Transcrição da Família Snail/genética , Idoso , Animais , Neoplasias dos Ductos Biliares/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Metástase Neoplásica/genética , Fosfatidilinositol 3-Quinases/metabolismo , Prognóstico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fatores de Transcrição da Família Snail/metabolismo , Regulação para Cima
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