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1.
J Cell Mol Med ; 28(12): e18487, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39031722

RESUMO

Premature ovarian insufficiency (POI) is one of the important causes of female infertility. Yet the aetiology for POI is still elusive. FBXW7 (F-box with 7 tandem WD) is one of the important components of the Skp1-Cullin1-F-box (SCF) E3 ubiquitin ligase. FBXW7 can regulate cell growth, survival and pluripotency through mediating ubiquitylation and degradation of target proteins via triggering the ubiquitin-proteasome system, and is associated with tumorigenesis, haematopoiesis and testis development. However, evidence establishing the function of FBXW7 in ovary is still lacking. Here, we showed that FBXW7 protein level was significantly decreased in the ovaries of the cisplatin-induced POI mouse model. We further showed that mice with oocyte-specific deletion of Fbxw7 demonstrated POI, characterized with folliculogenic defects, early depletion of follicle reserve, disordered hormonal secretion, ovarian dysfunction and female infertility. Impaired oocyte-GCs communication, manifested as down-regulation of connexin 37, may contribute to follicular development failure in the Fbxw7-mutant mice. Furthermore, single-cell RNA sequencing and in situ hybridization results indicated an accumulation of Clu and Ccl2 transcripts, which may alter follicle microenvironment deleterious to oocyte development and accelerate POI. Our results establish the important role of Fbxw7 in folliculogenesis and ovarian function, and might provide valuable information for understanding POI and female infertility.


Assuntos
Proteína 7 com Repetições F-Box-WD , Oócitos , Folículo Ovariano , Insuficiência Ovariana Primária , Animais , Feminino , Insuficiência Ovariana Primária/genética , Insuficiência Ovariana Primária/metabolismo , Insuficiência Ovariana Primária/patologia , Proteína 7 com Repetições F-Box-WD/metabolismo , Proteína 7 com Repetições F-Box-WD/genética , Oócitos/metabolismo , Camundongos , Folículo Ovariano/metabolismo , Folículo Ovariano/crescimento & desenvolvimento , Folículo Ovariano/patologia , Modelos Animais de Doenças , Deleção de Genes , Camundongos Knockout , Infertilidade Feminina/genética , Infertilidade Feminina/metabolismo , Infertilidade Feminina/patologia , Cisplatino/efeitos adversos
2.
Cell Commun Signal ; 22(1): 283, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783346

RESUMO

BACKGROUND: In addition to functioning as a precise monitoring mechanism in cell cycle, the anaphase-promoting complex/cyclosome (APC/C) is reported to be involved in regulating multiple metabolic processes by facilitating the ubiquitin-mediated degradation of key enzymes. Fatty acid oxidation is a metabolic pathway utilized by tumor cells that is crucial for malignant progression; however, its association with APC/C remains to be explored. METHODS: Cell cycle synchronization, immunoblotting, and propidium iodide staining were performed to investigate the carnitine palmitoyltransferase 1 C (CPT1C) expression manner. Proximity ligation assay and co-immunoprecipitation were performed to detect interactions between CPT1C and APC/C. Flow cytometry, 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2 H-tetrazolium, inner salt (MTS) assays, cell-scratch assays, and transwell assays and xenograft transplantation assays were performed to investigate the role of CPT1C in tumor progression in vitro and in vivo. Immunohistochemistry was performed on tumor tissue microarray to evaluate the expression levels of CPT1C and explore its potential clinical value. RESULTS: We identified CPT1C as a novel APC/C substrate. CPT1C protein levels exhibited cell cycle-dependent fluctuations, peaking at the G1/S boundary. Elevated CPT1C accelerated the G1/S transition, facilitating tumor cell proliferation in vitro and in vivo. Furthermore, CPT1C enhanced fatty acid utilization, upregulated ATP levels, and decreased reactive oxygen species levels, thereby favoring cell survival in a harsh metabolic environment. Clinically, high CPT1C expression correlated with poor survival in patients with esophageal squamous cell carcinoma. CONCLUSIONS: Overall, our results revealed a novel interplay between fatty acid utilization and cell cycle machinery in tumor cells. Additionally, CPT1C promoted tumor cell proliferation and survival by augmenting cellular ATP levels and preserving redox homeostasis, particularly under metabolic stress. Therefore, CPT1C could be an independent prognostic indicator in esophageal squamous cell carcinoma.


Assuntos
Ciclossomo-Complexo Promotor de Anáfase , Carnitina O-Palmitoiltransferase , Carnitina O-Palmitoiltransferase/metabolismo , Carnitina O-Palmitoiltransferase/genética , Humanos , Animais , Linhagem Celular Tumoral , Ciclossomo-Complexo Promotor de Anáfase/metabolismo , Ciclossomo-Complexo Promotor de Anáfase/genética , Metabolismo Energético/genética , Regulação para Cima , Progressão da Doença , Proliferação de Células , Camundongos Nus , Camundongos , Feminino , Masculino , Fase S , Camundongos Endogâmicos BALB C
3.
Int J Mol Sci ; 25(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38473940

RESUMO

Phytopathogenic fungi normally secrete large amounts of CWDEs to enhance infection of plants. In this study, we identified and characterized a secreted glycosyl hydrolase 5 family member in Sclerotinia sclerotiorum (SsGH5, Sclerotinia sclerotiorum Glycosyl Hydrolase 5). SsGH5 was significantly upregulated during the early stages of infection. Knocking out SsGH5 did not affect the growth and acid production of S. sclerotiorum but resulted in decreased glucan utilization and significantly reduced virulence. In addition, Arabidopsis thaliana expressing SsGH5 became more susceptible to necrotrophic pathogens and basal immune responses were inhibited in these plants. Remarkably, the lost virulence of the ΔSsGH5 mutants was restored after inoculating onto SsGH5 transgenic Arabidopsis. In summary, these results highlight that S. sclerotiorum suppresses the immune responses of Arabidopsis through secreting SsGH5, and thus exerts full virulence for successful infection.


Assuntos
Arabidopsis , Ascomicetos , Arabidopsis/metabolismo , Hidrolases/metabolismo , Virulência , Imunidade Vegetal/fisiologia , Plantas , Doenças das Plantas/microbiologia
4.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(4): 404-410, 2024 Apr 10.
Artigo em Zh | MEDLINE | ID: mdl-38565504

RESUMO

OBJECTIVE: To explore the genetic background for a patient with refractory myelodysplastic/myeloproliferative neoplasm (MDS/MPN) with co-morbid neutrophilia patient. METHODS: A MDS/MPN patient who was admitted to the First Affiliated Hospital of Nanjing Medical University in May 2021 was selected as the study subject. RNA sequencing was carried out to identify fusion genes in his peripheral blood mononuclear cells. Fusion gene sequence was searched through transcriptome-wide analysis with a STAR-fusion procedure. The novel fusion genes were verified by quantitative real-time PCR and Sanger sequencing. RESULTS: The patient, a 67-year-old male, had progressive thrombocytopenia. Based on the morphological and molecular examinations, he was diagnosed as MDS/MPN with co-morbid neutropenia, and was treated with demethylating agents and Bcl-2 inhibitors. Seventeen months after the diagnosis, he had progressed to AML. A novel fusion gene NCOR1::GLYR1 was identified by RNA-sequencing in his peripheral blood sample, which was verified by quantitative real-time PCR and Sanger sequencing. The patient had attained morphological remission after a DCAG regimen (a combinatory chemotherapy of decitabine, cytarabine, aclarubicin and granulocyte colony-stimulating factors) plus Chidamide treatment. A significant decrease in the NCOR1::GLYR1 expression was revealed by quantitative real-time PCR at post-chemotherapy evaluation. CONCLUSION: NCOR1::GLYR1 gene is considered as the pathogenic factor for the MDS/MPN patient with neutropenia.


Assuntos
Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Neutropenia , Masculino , Humanos , Idoso , Síndromes Mielodisplásicas/genética , Leucócitos Mononucleares , Citarabina/uso terapêutico , Correpressor 1 de Receptor Nuclear
5.
Z Gastroenterol ; 61(6): 680-682, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36470287

RESUMO

Obstruction of the colon caused by a fecalith is not a rare condition, but endoscopic attempts at removal of the fecalith are often unsuccessful because of the size of the fecalith and its extremely hard stone-like consistency. We report a case of bowel obstruction of over two weeks' duration caused by a giant colonic fecalith. Conservative treatments including insertion of a gastric tube and enemas failed to resolve the obstruction. After an initial unsuccessful attempt at fecalith removal by colonoscopy using a snare, we successfully resolved the bowel obstruction over the course of subsequent colonoscopies with endoscopic fenestration of the fecalith and placement of a transrectal gastric tube for directed instillation of the enema fluid, and we were able to avoid surgical intervention in this case.


Assuntos
Impacção Fecal , Obstrução Intestinal , Humanos , Impacção Fecal/diagnóstico , Impacção Fecal/diagnóstico por imagem , Obstrução Intestinal/diagnóstico por imagem , Obstrução Intestinal/etiologia , Colo , Colonoscopia/efeitos adversos , Cateterismo/efeitos adversos
6.
BMC Genomics ; 23(1): 514, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35840887

RESUMO

BACKGROUND: Ammonium is an important raw material for biomolecules and life activities, and the toxicity of ammonium is also an important ecological and agricultural issue. Ammonium toxicity in yeast has only recently been discovered, and information on its mechanism is limited. In recent years, environmental pollution caused by nitrogen-containing wastewater has been increasing. In addition, the use of yeast in bioreactors to produce nitrogen-containing compounds has been developed. Therefore, research on resistance mechanisms that allow yeast to grow under conditions of high concentrations of ammonium has become more and more important. RESULTS: To further understand the resistance mechanism of yeast to grow under high concentration of ammonium, we used NH4Cl to screen a yeast non-essential gene-deletion library. We identified 61 NH4Cl-sensitive deletion mutants from approximately 4200 mutants in the library, then 34 of them were confirmed by drop test analysis. Enrichment analysis of these 34 genes showed that biosynthesis metabolism, mitophagy, MAPK signaling, and other pathways may play important roles in NH4Cl resistance. Transcriptome analysis under NH4Cl stress revealed 451 significantly upregulated genes and 835 significantly downregulated genes. The genes are mainly enriched in: nitrogen compound metabolic process, cell wall, MAPK signaling pathway, mitophagy, and glycine, serine and threonine metabolism. CONCLUSIONS: Our results present a broad view of biological pathways involved in the response to NH4Cl stress, and thereby advance our understanding of the resistance genes and cellular transcriptional regulation under high concentration of ammonium.


Assuntos
Compostos de Amônio , Saccharomyces cerevisiae , Compostos de Amônio/toxicidade , Genoma Fúngico , Nitrogênio/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Transcriptoma
7.
J Adv Nurs ; 78(3): 750-764, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34363625

RESUMO

AIMS: To examine patient-caregiver concordances about psychological distress among Chinese patients with breast cancer undergoing chemotherapy and identify factors related to concordance among patients and family caregivers. DESIGN: Cross-sectional study. METHODS: From October 2019 to June 2020, 137 patient-caregiver dyads were enrolled. Sociodemographic information, the distress thermometer (including the problem list), the Distress Disclosure Index and the Family Adaptability and Cohesion Evaluation Scale were used to collect data. Data were analysed using intraclass correlation coefficients (ICC), kappa statistics, two related samples test, chi-square tests and/or Fisher's exact tests and binary logistic regression. RESULTS: Overall, fair agreement was identified between patients' and caregivers' reports (intraclass correlation coefficients [ICC] = .528). Patients reported significantly higher psychological distress scores than paired caregiver reports. Lower psychological distress concordance was found among patients with comorbidities (odds ratio [OR], 0.352; 95% confidence interval [CI], 0.155-0.798) and lower levels of self-disclosure (OR, 0.402; 95% CI, 0.186-0.868). CONCLUSION: There was relatively low concordance between patients' reports and caregivers' perceptions of psychological distress. Family caregivers tended to underestimate patients' psychological distress. A comorbid condition and lower levels of self-disclosure contributed to this bias. IMPACT: Having an awareness of the incongruence between patient and caregiver may help healthcare providers better interpret caregiver assessments. Healthcare providers should reinforce patient-caregiver dyadic psychosocial education to improve concordance. More psychological care and substantial emotional support should be provided for Chinese breast cancer patients undergoing chemotherapy by family caregivers and healthcare providers.


Assuntos
Neoplasias da Mama , Neoplasias , Angústia Psicológica , Neoplasias da Mama/tratamento farmacológico , Cuidadores , China , Estudos Transversais , Feminino , Humanos , Qualidade de Vida , Estresse Psicológico
8.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 39(3): 343-349, 2022 Mar 10.
Artigo em Zh | MEDLINE | ID: mdl-35315050

RESUMO

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease which is associated with genetic and environmental factors, though the pathogenesis is still unclear and there is also a lack of effective treatment. With the rapid advance of genetic testing techniques, over 30 genes have been associated with the disease. Some ALS patients harboring genetic variants may present unique clinical characteristics and particular mode of inheritance, but the correlation between genotype and phenotype is still not very clear. Studies have shown that research on the pathogenic genes of ALS is important for the diagnosis and selection of potential drug targets. Here the pathogenic genes of ALS, in particular the newly discovered genes, and their underlying mechanisms are reviewed. The necessity of genetic testing for ALS patients is also stressed.


Assuntos
Esclerose Lateral Amiotrófica , Doenças Neurodegenerativas , Esclerose Lateral Amiotrófica/genética , Testes Genéticos , Genótipo , Humanos , Doenças Neurodegenerativas/genética , Fenótipo
9.
Environ Sci Technol ; 55(9): 6329-6339, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33848140

RESUMO

The potential coexistence and interaction of bromine and polyamide membranes during membrane-based water treatment prompts us to investigate the effect of bromine on membrane performance. For fully aromatic polyamide membrane NF90 exposed under a mild bromination condition (10 mg/L), bromine incorporation resulted in more negatively charged (-13 vs -25 mV) and hydrophobic (55.2 vs 58.9°) surfaces and narrower pore channels (0.3 vs 0.29 nm). The permeabilities of water and neutral solutes were reduced by 64 and 69-87%, respectively, which was attributed to the decreased effective pore radius and hydrophilicity. NaCl permeability was reduced by 90% as a synergistic result of enhanced size exclusion and charge repulsion. The further exposure (100 and 500 mg/L bromine) resulted in a more hydrophobic surface (61.7 and 65.5°) and the minor further reduction for water and solute permeabilities (1-9%). Compared with chlorine, the different incorporation efficiency and properties (e.g., atomic size, hydrophilicity) of bromine resulted in opposite trends and/or different degrees for the variation of physicochemical properties and filtration performance of membranes. The bromine incorporation, the shift and disappearance of three characteristic bands, and the increased O/N ratio and calcium content indicated the degradation pathways of N-bromination and bromination-promoted hydrolysis under mild bromination conditions (480 mg/L·h). The further ring-bromination occurred after severe bromine exposure (4800-24,000 mg/L·h). The semi-aromatic polyamide membrane NF270 underwent a similar but less significant deteriorated filtration performance compared with NF90, which requires a different explanation.


Assuntos
Nylons , Purificação da Água , Bromo , Filtração , Membranas Artificiais
10.
Support Care Cancer ; 29(12): 8027-8044, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34226959

RESUMO

PURPOSE: Breast cancer-related lymphedema (BCRL) self-management plays an important role in the lymphedema therapy. However, clinical knowledge of BCRL self-management remains minimal. This study aims to explore the experience surrounding lymphedema self-management from the perspectives of BCRL patients and healthcare professionals. METHODS: Semi-structured interviews were implemented with BCRL patients and healthcare professionals. Audio-recordings of interviews were transcribed verbatim and thematic analysis was undertaken to analyze the interview data. RESULTS: Thirteen BCRL patients (aged 34-65 years) and nine healthcare professionals (2 physicians, 4 nurses, and 3 lymphedema therapists) were interviewed. Five themes emerged from interviews with participants: knowledge-attitude-practice surrounding lymphedema self-management, emotional reactions towards lymphedema self-management, factors influencing lymphedema self-management, support needs for lymphedema self-management, healthcare professional support of BCRL self-management. CONCLUSIONS: This study showed knowledge-attitude-practice, feelings, influencing factors, roles, dilemmas, and support needs regarding BCRL self-management. Greater effort is required for healthcare professionals to strengthen the lymphedema self-management. Providing more educational program and holistic support, and strengthening the facilitators and controlling the barriers might benefit promoting lymphedema self-management. Likewise, healthcare professionals need adequate training to be able to meet patients' self-management support needs.


Assuntos
Linfedema Relacionado a Câncer de Mama , Neoplasias da Mama , Linfedema , Neoplasias da Mama/complicações , Neoplasias da Mama/terapia , Atenção à Saúde , Feminino , Pessoal de Saúde , Humanos , Linfedema/etiologia , Linfedema/terapia
11.
Small ; 16(1): e1905083, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31808621

RESUMO

Tetrahedral NiS2 /NiSe2 heterocages with rich-phase boundaries are synthesized through a simultaneous sulfuration/selenylation process using Ni-based acetate hydroxide prisms as precursor. Such a nanocage-like NiS2 /NiSe2 heterostructure can expose more active sites, accelerate the mass transport of the ions/gas, and optimize the interfacial electronic structure, which shows a significantly lower overpotential of 290 mV at 20 mA cm-2 than those of NiS/NiS2 and NiSe2 as counterparts. The experimental characterizations and theoretical density functional theory (DFT) calculations unveil that the interfacial electron transfer from NiSe2 to NiS2 at the heterointerface can modulate the electronic structure of NiS2 /NiSe2 , which further cooperates synergistically to change the Gibbs free energy of oxygen-containing intermediates as the rate-determining step (RDS) from 2.16 eV (NiSe2 ) and 2.10 eV (NiS2 ) to 1.86 eV (NiS2 /NiSe2 heterostructures) during the oxygen evolution reaction (OER) process. And as a result, tetrahedral NiS2 /NiSe2 heterocages with dual-phase synergy efficiently trigger the OER process, and accelerate the OER kinetics. This work provides insights into the roles of the interfacial electron transfer in electrocatalysis, and can be an admirable strategy to modulate the electronic structure for developing highly active electrocatalysts.

12.
Biomed Eng Online ; 19(1): 59, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32727522

RESUMO

BACKGROUND: The anomalous origin of the right coronary artery (RCA) from the left coronary artery sinus (AORL) is one of the abnormal origins of the coronary arteries. Most of these issues rarely have any effects on human health, but some individuals may exhibit symptoms, such as myocardial ischemia or even sudden death. Recently, researchers have investigated the AORL through clinical cases, but studies based on computational fluid dynamics (CFD) have rarely been reported. In this study, the hemodynamic changes between the normal origin of the RCA and the AORL are compared based on numerical simulation results. METHODS: Realistic three-dimensional (3D) models of the 16 normal right coronary arteries and 26 abnormal origins of the RCAs were constructed, respectively. The blood flow was numerically simulated using the ANSYS software. This study used a one-way fluid-solid coupling finite element model, wherein the blood is assumed to be an incompressible Newtonian fluid, and the vessel is assumed to be made of an isotropic linear elastic material. RESULTS: The cross-sectional area differences between the inlet of the normal group and that of the abnormal group were significant (P < 0.0001). Moreover, there were significant differences in the volumetric flow (P = 0.0001) and pressure (P = 0.0002). Positive correlation exists for the ratio of the cross-sectional area of the RCA to the inlet area of the ascending aorta (AAO), and the ratio of the inlet volumetric flow of the RCA to the volumetric flow of the AAO, in the normal (P = 0.0001, r = 0.8178) and abnormal (P = 0.0033, r = 0.6107) groups. CONCLUSION: This study demonstrates that the cross-sectional area of the AORL inlet may cause ischemia symptoms. The results obtained by this study may contribute to the further understanding of the clinical symptoms of the AORL based on the hemodynamics.


Assuntos
Simulação por Computador , Vasos Coronários/patologia , Vasos Coronários/fisiopatologia , Hemodinâmica , Hidrodinâmica
13.
J Nurs Manag ; 28(1): 139-147, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31746069

RESUMO

AIM: To describe the value, knowledge and implementation of evidenced-based practice (EBP) among Chinese nurse managers and explore its influencing factors. BACKGROUND: Although much of literature have reported the importance of nurse managers in pushing EBP progress and encouraged them to engage in EBP activities, the extent to which nurse managers engage in EBP is unclear. METHODS: A cross-sectional web-based survey was applied to 1,166 nurse managers recruited from 54 hospitals in Guangdong Province, China. Descriptive statistics, t-tests or one-way ANOVAs, Spearman's correlation and multiple regression analysis were used to analyse the data. RESULTS: The average scores of the Quick-EBP-VIK were with the mean of 2.62 (±0.56). Result showed that educational background, professional title, whether they have received EBP education or training, and EBP organisational culture and readiness are the factors influencing managers' total Quick-EBP-VIK score, with 43.5% of the variance explained by these factors. CONCLUSIONS: Nurse managers had positive attitudes towards EBP, but they lacked the EBP knowledge and rarely implemented EBP. Furthermore, supportive organisational environment, effective education and training can help to enhance EBP knowledge and skills of managers. IMPLICATIONS OF NURSING MANAGEMENT: The competence of nurse managers for EBP implementation should be taken seriously. Personal and organisational strategies which can strengthen managers' EBP knowledge and skills need to be developed and conducted.


Assuntos
Prática Clínica Baseada em Evidências/métodos , Enfermeiros Administradores/psicologia , Adulto , Análise de Variância , Atitude do Pessoal de Saúde , China , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Enfermeiros Administradores/estatística & dados numéricos , Inquéritos e Questionários
14.
J Neurophysiol ; 121(5): 1718-1734, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30786219

RESUMO

Two macroscopic parameters describe the interstitial diffusion of substances in the extracellular space (ECS) of the brain, the ECS volume fraction α and the diffusion tortuosity λ. Past methods based on sampling the extracellular concentration of a membrane-impermeable ion tracer, such as tetramethylammonium (TMA+), can characterize either the dynamic α(t) alone or the constant α and λ in resting state but never the dynamic α(t) and λ(t) simultaneously in short-lived brain events. In this work, we propose to use a sinusoidal method of TMA+ to provide time-resolved quantification of α(t) and λ(t) in acute brain events. This method iontophoretically injects TMA+ in the brain ECS by a sinusoidal time pattern, samples the resulting TMA+ diffusion waveform at a distance, and analyzes the transient modulations of the amplitude and phase lag of the sampled TMA+ waveform to infer α(t) and λ(t). Applicability of the sinusoidal method was verified through computer simulations of the sinusoidal TMA+ diffusion waveform in cortical spreading depression. Parameter sensitivity analysis identified the sinusoidal frequency and the interelectrode distance as two key operating parameters. Compared with other TMA+-based methods, the sinusoidal method can more accurately capture the dynamic α(t) and λ(t) in acute brain events and is equally applicable to other pathological episodes such as epilepsy, transient ischemic attack, and brain injury. Future improvement of the method should focus on high-fidelity extraction of the waveform amplitude and phase angle. NEW & NOTEWORTHY An iontophoretic sinusoidal method of tetramethylammonium is described to capture the dynamic brain extracellular space volume fraction α and diffusion tortuosity λ. The sinusoidal frequency and interelectrode distance are two key operating parameters affecting the method's accuracy in capturing α(t) and λ(t). High-fidelity extraction of the waveform amplitude and phase lag is critical to successful sinusoidal analyses.


Assuntos
Encéfalo/citologia , Potenciais Evocados , Espaço Extracelular/fisiologia , Modelos Neurológicos , Técnicas de Rastreamento Neuroanatômico/métodos , Algoritmos , Animais , Encéfalo/fisiologia , Difusão , Espaço Extracelular/metabolismo , Marcadores do Trato Nervoso/farmacocinética , Compostos de Amônio Quaternário/farmacocinética , Ratos , Tempo de Reação
15.
J Neurophysiol ; 121(5): 1735-1747, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30786223

RESUMO

Extracellular diffusion in the brain is customarily characterized by two parameters, the extracellular space (ECS) volume fraction α and the diffusion tortuosity λ. How these two parameters are temporarily modified and correlated in a physiological/pathological event remains unclear to date. Using tetramethylammonium (TMA+) as an ECS ion tracer in a newly updated iontophoretic sinusoidal method, we studied in this work the dynamic α(t) and λ(t) in rat somatosensory cortex during spreading depression (SD). Temporal variations of α(t) and λ(t), as evoked by SD, were obtained through analyses of the extracellular TMA+ diffusion waveform resulting from a sinusoidally modulated point source. Most of the time, cortical SD induced coordinated α(t) decreases and λ(t) increases. In rare occasions, SD induced sole decreases of α(t) with no changes in λ(t). The independent modulation of α(t) and λ(t) was neither associated with cortical anatomy nor with the specific shape of the SD field potential wave. Changes of α(t) and λ(t) often took place acutely at the onset of SD, followed by a more transient modulation. Compared with the prior iontophoretic methods of TMA+, the sinusoidal method provides time-resolved quantification of α(t) and λ(t) in relative terms but also raises a higher property requirement on the TMA+-selective microelectrode. The sinusoidal method could become a valuable tool in the studies of the dynamic ECS response in various brain events. NEW & NOTEWORTHY An iontophoretic sinusoidal method was applied to study the dynamic changes of two extracellular space parameters, the extracellular volume fraction α(t) and tortuosity λ(t), in the brain during cortical spreading depression. Both parameters showed coordinated (most often) and independent (rarely) modulations in spreading depression. The sinusoidal method is equally applicable to other acute pathological events and a valuable tool to study the functional role of extracellular space in brain events.


Assuntos
Córtex Cerebral/fisiologia , Depressão Alastrante da Atividade Elétrica Cortical , Espaço Extracelular/fisiologia , Algoritmos , Animais , Córtex Cerebral/citologia , Feminino , Masculino , Técnicas de Rastreamento Neuroanatômico/métodos , Marcadores do Trato Nervoso/farmacocinética , Neurônios/fisiologia , Compostos de Amônio Quaternário/farmacocinética , Ratos , Ratos Sprague-Dawley , Tempo de Reação
16.
Clin Genet ; 96(2): 176-182, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31069783

RESUMO

Distal hereditary motor neuropathy (dHMN) is a clinically and genetically heterogeneous group of inherited neuropathies characterized by distal limb muscle wasting and weakness with no or minimal sensory abnormalities. To investigate the clinical and genetic features of dHMN caused by WARS mutations in mainland China, we performed Sanger sequencing of the coding and untranslated region (UTR) regions of WARS in 160 unresolved dHMN and Charcot-Marie-Tooth (CMT) index patients. We detected a novel heterozygous variant c.941A>G (p.Asp314Gly) of WARS in an index patient from an autosomal dominant dHMN family including five affected members over three generations. The variant completely co-segregates with the dHMN phenotype in the family, and it was classified as likely pathogenic according to the American College of Medical Genetics and Genomics standards and guidelines. The clinical features included juvenile to adult onset (15-23 years), distal wasting and weakness, minimal sensory disturbance and length-dependent motor axonal degeneration with CMT examination score ranging from 6 to 10. Our report further confirms the role of WARS in dHMN and indicates that the variant c.941A>G (p.Asp314Gly) of WARS is related to a mild to moderate affected and later onset phenotype of dHMN.


Assuntos
Estudos de Associação Genética , Predisposição Genética para Doença , Neuropatia Hereditária Motora e Sensorial/diagnóstico , Neuropatia Hereditária Motora e Sensorial/genética , Mutação , Fenótipo , Triptofano-tRNA Ligase/genética , Adolescente , Idoso , Alelos , Sequência de Aminoácidos , Substituição de Aminoácidos , Análise Mutacional de DNA , Eletromiografia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Linhagem , Adulto Jovem
17.
Phys Rev Lett ; 121(26): 261101, 2018 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-30636147

RESUMO

Here we present a new test of the equivalence principle designed to search for the possible violation of gravitational parity using test bodies with different chiralities. The test bodies are a pair of left- and right-handed quartz crystals, whose gravitational acceleration difference is measured by a rotating torsion pendulum. The result shows that the acceleration difference towards Earth Δa_{left-right}=[-1.7±4.1(stat)±4.4(syst)]×10^{-15} m s^{-2} (1-σ statistical uncertainty), correspondingly the Eötvös parameter η=[-1.2±2.8(stat)±3.0(syst)]×10^{-13}. This is the first reported experimental test of the equivalence principle for chiral masses and opens a new way to the search for the possible parity-violating gravitation.

18.
Chemistry ; 24(70): 18689-18695, 2018 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-30318819

RESUMO

Electrochemical water splitting is a promising way for the sustainable production of hydrogen, but the efficiency of the overall water-splitting reaction largely depends on the oxygen evolution reaction (OER) because of its sluggish kinetics. Herein, a series of hierarchical ZnCo2 O4 /Co3 O4 /NC-CNT (NC-CNT=nitrogen-rich carbon nanotube) mesoporous dodecahedrons grafted to carbon nanotubes have been synthesized from ZnCo bimetallic zeolitic imidazolate frameworks (ZnCo-ZIFs) through sequential pyrolysis in nitrogen and mild oxidation in air. The simultaneous modulation of oxygen vacancies, composition, and hierarchical mesoporous architecture remarkably enhanced their electronic conduction and the amount and reactivity of accessible actives; thus boosting their intrinsic activity in the OER. The optimal ZnCo2 O4 /Co3 O4 /NC-CNT-700 sample exhibited a large current density of 50 mA cm-2 at a potential of 1.65 V, a small Tafel slope of 88.5 mV dec-1 , and superior stability in alkaline media. This work should provide a facile strategy for the rational design of advanced OER catalysts by simultaneous engineering of oxygen vacancies and composition.

19.
Reprod Biol Endocrinol ; 16(1): 85, 2018 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-30176887

RESUMO

BACKGROUND: Cisplatin (CDDP), a widely used chemotherapeutic agent, can induce excessive granulosa cell apoptosis, follicle loss and even premature ovarian insufficiency (POI). However, the mechanism remains elusive, although some studies have indicated the involvement of endoplasmic reticulum stress (ERS). The aim of our study was to investigate the possible mechanism ERS in CDDP-induced granulosa cell apoptosis and follicle loss. METHODS: A POI mouse model was generated by CDDP. The ovaries samples were collected and processed for isobaric tags for relative and absolute quantification analysis (iTRAQ) to screen out our interested proteins of HSPA5 and HSP90AB1, and the decline in their expression were verified by a real-time quantitative PCR and a western blotting assay. In vitro, human granulosa cells, KGN and COV434 cells were transfected with siRNA targeting HSPA5 and HSP90AB1 and then treated with CDDP, or treated with CDDP with/without CDDP+ 4-phenylbutyric acid (4-PBA) and 3-methyladenine (3-MA). The levels of ERS, autophagy and apoptosis were evaluated by western blotting, DALGreen staining and flow cytometry. In vivo, ovaries from mice that received intraperitoneal injections of saline, CDDP, CDDP+ 4-PBA and CDDP+ 3-MA were assayed by immunofluorescence, hematoxylin and eosin (H&E) staining for follicle counting, and terminal-deoxynucleotidyltransferase-mediated dUTP nick end labeling (TUNEL) staining for cell apoptosis assay. The plasma hormone levels were measured by an enzyme-linked immunosorbent assay (ELISA) kit. RESULTS: We have clarified the relationships between ERS, autophagy, and apoptosis in CDDP-induced granulosa cell apoptosis, both in vitro and in vivo. Alleviating ERS by inhibiting HSPA5 and HSP90AB1 attenuated CDDP-induced autophagy and apoptosis. 4-PBA treatment significantly attenuated CDDP-induced cell autophagy and apoptosis in cultured KGN and COV434 cells. However, inhibiting cell autophagy with 3-MA negligibly restored the CDDP-induced changes in ERS and apoptosis. In vivo experiments also demonstrated that treatment with 4-PBA, but not 3-MA, prevented CDDP-induced ovarian damage and hormone dysregulation. CONCLUSIONS: CDDP-induced ERS could promote autophagy and apoptosis in granulosa cells, causing excessive follicle loss and endocrine disorders. Alleviation of ERS with 4-PBA, but not of autophagy with 3-MA, protect against CDDP-induced granulosa cell apoptosis and ovarian damage. Thus, 4-PBA can be used to protect the ovary during chemotherapy in women.


Assuntos
Cisplatino/efeitos adversos , Células da Granulosa/efeitos dos fármacos , Ovário/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático , Feminino , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos C57BL , Ovário/patologia , Insuficiência Ovariana Primária/induzido quimicamente , Interferência de RNA
20.
BMC Cancer ; 18(1): 1269, 2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-30567513

RESUMO

BACKGROUND: Definite prognostic clinical factors of benefit for decitabine-based induction chemotherapy in elderly patients newly diagnosed with acute myeloid leukaemia (AML) are not identified. This study was designed to explore the potential biomarker, especially regeneration of haematopoiesis, of treatment response and survival in elderly patients with newly diagnosed AML. METHOD: We analysed the clinical data of 117 elderly AML patients who were treated with a decitabine dose of 15 mg/m2 for 5 days, granulocyte colony-stimulating factor of 300 µg/d for priming, plus cytarabine 10 mg/m2 q12h for 7 days and aclarubicin 10 mg/d for 4 days (D-CAG). RESULTS: After initial induction chemotherapy, the overall response rate and complete remission (CR) were 71.8% and 58.1%, respectively. Patients responding to the D-CAG regimen achieved higher platelet counts on day 14 after initial treatment (p < 0.001). Median counts were 59.5 × 109/L in the CR group, 37 × 109/L in the partial remission group and 28 × 109/L in the non-responsive group. We then classified patients into those who achieved platelet counts≥60 × 109/L or 100 × 109/L on day 14 after D-CAG vs. those who did not. Platelet counts≥60 × 109/L or 100 × 109/L on day 14 were significantly associated with superior CR, overall survival and disease-free survival (80.9% vs. 45.3% p < 0.001,16.5 vs. 9.1 months p = 0.009 and 16.3 vs. 7.4 months p = 0.024; 85.2% vs. 50% p = 0.001, 31 vs. 10.1 months p = 0.003 and 16.9 vs. 8.9 months p = 0.006). Multivariate analysis confirmed that poor cytogenetics (p = 0.010) and FLT3-ITD mutation (p = 0.007) were identified as independent factors of OS, but not platelet count (p = 0.091). However, platelet count≥100 × 109/L on day 14 was an independent prognostic factor of CR and DFS. CONCLUSION: Platelet count recovery on day 14 after D-CAG induction chemotherapy is associated with response. TRIAL REGISTRATION: D-CAG regimen was registered on ChicTR with number 11001700 .


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Plaquetas/efeitos dos fármacos , Decitabina/administração & dosagem , Leucemia Mieloide Aguda/tratamento farmacológico , Aclarubicina/administração & dosagem , Aclarubicina/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , China , Citarabina/administração & dosagem , Citarabina/efeitos adversos , Decitabina/efeitos adversos , Intervalo Livre de Doença , Feminino , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Fator Estimulador de Colônias de Granulócitos/efeitos adversos , Humanos , Quimioterapia de Indução/efeitos adversos , Leucemia Mieloide Aguda/sangue , Leucemia Mieloide Aguda/patologia , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Prognóstico , Indução de Remissão
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