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1.
Int J Cancer ; 154(3): 548-560, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37727982

RESUMO

Telomerase activation is a crucial step in melanomagenesis, often occurring because of ultraviolet radiation (UVR)-induced mutations at the telomerase gene (TERT) promoter and rendering TERT transcription in response to the activated Raf-MAP kinase pathway by BRAFV600E mutation. Due to the excessively long telomeres in mice, this process does not occur during melanomagenesis in mouse models. To investigate the impact of telomere dysfunction on melanomagenesis, BrafV600E was induced in generations 1 and 4 (G1 and G4) of Tert-/- mice. Our findings revealed that, regardless of UVR exposure, melanoma development was delayed in G4 mice, which had shorter telomeres compared to G1 and wild-type C57BL/6J (G0) mice. Moreover, many G4 tumors displayed an accumulation of excessive DNA damage, as evidenced by increased γH2A.X staining. Tumors from UVR-exposed mice exhibited elevated p53 protein expression. Cultured tumor cells isolated from G4 mice displayed abundant chromosomal fusions and rearrangements, indicative of telomere dysfunction in these cells. Additionally, tumor cells derived from UVB-exposed mice exhibited constitutively elevated expression of mutant p53 proteins, suggesting that p53 was a target of UVB-induced mutagenesis. Taken together, our findings suggest that telomere dysfunction hampers melanomagenesis, and targeting telomere crisis-mediated genomic instability may hold promise for the prevention and treatment of melanoma.


Assuntos
Melanoma , Proteínas Proto-Oncogênicas B-raf , Telomerase , Animais , Camundongos , Melanoma/genética , Melanoma/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Telomerase/genética , Telomerase/metabolismo , Telômero/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Raios Ultravioleta/efeitos adversos
2.
Small ; : e2401624, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773869

RESUMO

The poor machinability of halide perovskite crystals severely hampered their practical applications. Here a high-throughput growth method is reported for armored perovskite single-crystal fibers (SCFs). The mold-embedded melt growth (MEG) method provides each SCF with a capillary quartz shell, thus guaranteeing their integrality when cutting and polishing. Hundreds of perovskite SCFs, exemplified by CsPbBr3, CsPbCl3, and CsPbBr2.5I0.5, with customized dimensions (inner diameters of 150-1000 µm and length of several centimeters), are grown in one batch, with all the SCFs bearing homogeneity in shape, orientation, and optical/electronic properties. Versatile assembly protocols are proposed to directly integrate the SCFs into arrays. The assembled array detectors demonstrated low-level dark currents (< 1 nA) with negligible drift, low detection limit (< 44.84 nGy s-1), and high sensitivity (61147 µC Gy-1 cm-2). Moreover, the SCFs as isolated pixels are free of signal crosstalk while showing uniform X-ray photocurrents, which is in favor of high spatial resolution X-ray imaging. As both MEG and the assembly of SCFs involve none sophisticated processes limiting the scalable fabrication, the strategy is considered to meet the preconditions of high-throughput productions.

3.
Cardiovasc Diabetol ; 23(1): 150, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702777

RESUMO

BACKGROUND: Vasculopathy is the most common complication of diabetes. Endothelial cells located in the innermost layer of blood vessels are constantly affected by blood flow or vascular components; thus, their mechanosensitivity plays an important role in mediating vascular regulation. Endothelial damage, one of the main causes of hyperglycemic vascular complications, has been extensively studied. However, the role of mechanosensitive signaling in hyperglycemic endothelial damage remains unclear. METHODS: Vascular endothelial-specific Piezo1 knockout mice were generated to investigate the effects of Piezo1 on Streptozotocin-induced hyperglycemia and vascular endothelial injury. In vitro activation or knockdown of Piezo1 was performed to evaluate the effects on the proliferation, migration, and tubular function of human umbilical vein endothelial cells in high glucose. Reactive oxygen species production, mitochondrial membrane potential alternations, and oxidative stress-related products were used to assess the extent of oxidative stress damage caused by Piezo1 activation. RESULTS: Our study found that in VECreERT2;Piezo1flox/flox mice with Piezo1 conditional knockout in vascular endothelial cells, Piezo1 deficiency alleviated streptozotocin-induced hyperglycemia with reduced apoptosis and abscission of thoracic aortic endothelial cells, and decreased the inflammatory response of aortic tissue caused by high glucose. Moreover, the knockout of Piezo1 showed a thinner thoracic aortic wall, reduced tunica media damage, and increased endothelial nitric oxide synthase expression in transgenic mice, indicating the relief of endothelial damage caused by hyperglycemia. We also showed that Piezo1 activation aggravated oxidative stress injury and resulted in severe dysfunction through the Ca2+-induced CaMKII-Nrf2 axis in human umbilical vein endothelial cells. In Piezo1 conditional knockout mice, Piezo1 deficiency partially restored superoxide dismutase activity and reduced malondialdehyde content in the thoracic aorta. Mechanistically, Piezo1 deficiency decreased CaMKII phosphorylation and restored the expression of Nrf2 and its downstream molecules HO-1 and NQO1. CONCLUSION: In summary, our study revealed that Piezo1 is involved in high glucose-induced oxidative stress injury and aggravated endothelial dysfunction, which have great significance for alleviating endothelial damage caused by hyperglycemia.


Assuntos
Glicemia , Diabetes Mellitus Experimental , Células Endoteliais da Veia Umbilical Humana , Canais Iônicos , Camundongos Knockout , Óxido Nítrico Sintase Tipo III , Estresse Oxidativo , Animais , Humanos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Diabetes Mellitus Experimental/metabolismo , Canais Iônicos/metabolismo , Canais Iônicos/genética , Glicemia/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Mecanotransdução Celular , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/deficiência , Células Cultivadas , Proliferação de Células , Apoptose , Masculino , Angiopatias Diabéticas/metabolismo , Angiopatias Diabéticas/fisiopatologia , Angiopatias Diabéticas/patologia , Angiopatias Diabéticas/genética , Angiopatias Diabéticas/etiologia , Movimento Celular , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/metabolismo , Aorta Torácica/metabolismo , Aorta Torácica/patologia , Aorta Torácica/fisiopatologia , Camundongos , Estreptozocina , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Endotélio Vascular/patologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética
4.
Environ Res ; 252(Pt 3): 118967, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38642643

RESUMO

Sulfadimidine (SM2) is an N-substituted derivative of p-aminobenzenesulfonyl structure. This study aimed to analyze the metabolism of SM2 in carp (Cyprinus carpio). The carps were fed with SM2 at a dose of 200 mg/(kg · bw) and then killed. The blood, muscle, liver, kidney, gill, other guts, and carp aquaculture water samples were collected. The UHPLC-Q-Exactive Plus Orbitrap-MS was adopted for determining the metabolites of SM2 in the aforementioned samples. Twelve metabolites, which were divided into metabolites in vivo and metabolites in vitro, were identified using Compound Discoverer software. The metabolic pathways in vivo of SM2 in carp included acetylation, hydroxylation, glucoside conjugation, glycine conjugation, carboxylation, glucuronide conjugation, reduction, and methylation. The metabolic pathways in vitro included oxidation and acetylation. This study clarified the metabolites and metabolic pathways of SM2 in carp and provided a reference for further pharmacodynamic evaluation and use in aquaculture.


Assuntos
Carpas , Carpas/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Redes e Vias Metabólicas , Sulfonamidas/metabolismo , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo , Espectrometria de Massas/métodos
5.
Proc Natl Acad Sci U S A ; 118(26)2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34155099

RESUMO

Multiple independent sequence variants of the hTERT locus have been associated with telomere length and cancer risks in genome-wide association studies. Here, we identified an intronic variable number tandem repeat, VNTR2-1, as an enhancer-like element, which activated hTERT transcription in a cell in a chromatin-dependent manner. VNTR2-1, consisting of 42-bp repeats with an array of enhancer boxes, cooperated with the proximal promoter in the regulation of hTERT transcription by basic helix-loop-helix transcription factors and maintained hTERT expression during embryonic stem-cell differentiation. Genomic deletion of VNTR2-1 in MelJuSo melanoma cells markedly reduced hTERT transcription, leading to telomere shortening, cellular senescence, and impairment of xenograft tumor growth. Interestingly, VNTR2-1 lengths varied widely in human populations; hTERT alleles with shorter VNTR2-1 were underrepresented in African American centenarians, indicating its role in human aging. Therefore, this polymorphic element is likely a missing link in the telomerase regulatory network and a molecular basis for genetic diversities of telomere homeostasis and age-related disease susceptibilities.


Assuntos
Repetições Minissatélites/genética , Polimorfismo Genético , Telomerase/genética , Ativação Transcricional , Negro ou Afro-Americano/genética , Idoso de 80 Anos ou mais , Animais , Sequência de Bases , Diferenciação Celular/genética , Linhagem Celular , Proliferação de Células/genética , Cromossomos Artificiais Bacterianos/genética , Elementos E-Box/genética , Genoma Humano , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Camundongos Nus , Neoplasias/genética , Neoplasias/patologia , Regiões Promotoras Genéticas , Ligação Proteica/genética , Deleção de Sequência/genética , Homeostase do Telômero/genética
6.
Br J Haematol ; 203(2): 295-303, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37488467

RESUMO

Emerging evidence has demonstrated that obesity impacts multiple immune-related diseases. It remains unclear whether and how obesity alters treatment outcomes in patients with primary immune thrombocytopenia (ITP). Thus, we retrospectively investigated 214 treatment-naïve patients who received standard high-dose dexamethasone therapy in Qilu Hospital. Patients with obesity showed significantly lower overall initial response (underweight vs. normal vs. overweight vs. obese: 85.7% vs. 85.2% vs. 72.0% vs. 52.3%, p = 0.001) and initial complete response ([CR], 71.4% vs. 70.4% vs. 53.3% vs. 27.3%, p < 0.001) rates. The same trend was observed in the 6-month sustained response (63.6% vs. 52.3% vs. 35.6% vs. 22.7%, p = 0.03) and sustained CR (36.4% vs. 44.6% vs. 24.4% vs. 9.1%, p = 0.01). The Kaplan-Meier analysis revealed a shortened duration of remission in the obese group (median duration of remission, not reached vs. 16 months vs. 2 months vs. 1 month, p = 0.002). In multivariate regression analysis, obesity was independently associated with poor initial and sustained responses, and an increased risk for relapse. In conclusion, obesity is a negative predictor for outcomes of corticosteroid treatment. A stratified strategy according to body mass index status may facilitate the precision management of ITP.


Assuntos
Púrpura Trombocitopênica Idiopática , Humanos , Púrpura Trombocitopênica Idiopática/complicações , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Estudos Retrospectivos , Corticosteroides/uso terapêutico , Resultado do Tratamento , Obesidade/complicações
7.
Molecules ; 28(19)2023 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-37836630

RESUMO

In order to separate the colloidal in high-turbidity water, a kind of magnetic composite (Fe3O4/HBPN) was prepared via the functional assembly of Fe3O4 and an amino-terminal hyperbranched polymer (HBPN). The physical and chemical characteristics of Fe3O4@HBPN were investigated by different means. The Fourier Transform infrared spectroscopy (FTIR) spectra showed that the characteristic absorption peaks positioned at 1110 cm-1, 1468 cm-1, 1570 cm-1 and 1641 cm-1 were ascribed to C-N, H-N-C, N-H and C=O bonds, respectively. The shape and size of Fe3O4/HBPN showed a different and uneven distribution; the particles clumped together and were coated with an oil-like film. Energy-dispersive spectroscopy (EDS) displayed that the main elements of Fe3O4/HBPN were C, N, O, and Fe. The superparamagnetic properties and good magnetic response were revealed by vibrating sample magnetometer (VSM) analysis. The characteristic diffraction peaks of Fe3O4/HBPN were observed at 2θ = 30.01 (220), 35.70 (311), 43.01 (400), 56.82 (511), and 62.32 (440), which indicated that the intrinsic phase of magnetite remained. The zeta potential measurement indicated that the surface charge of Fe3O4/HBPN was positive in the pH range 4-10. The mass loss of Fe3O4/HBPN in thermogravimetric analysis (TGA) proved thermal decomposition. The -C-NH2 or -C-NH perssad of HBPN were linked and loaded with Fe3O4 particles by the N-O bonds. When the Fe3O4/HBPN dosage was 2.5 mg/L, pH = 4-5, the kaolin concentration of 1.0 g/L and the magnetic field of 3800 G were the preferred reaction conditions. In addition, a removal efficiency of at least 86% was reached for the actual water treatment. Fe3O4/HBPN was recycled after the first application and reused five times. The recycling efficiency and removal efficiency both showed no significant difference five times (p > 0.05), and the values were between 84.8% and 86.9%.

8.
Molecules ; 28(15)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37570702

RESUMO

The aim of this study was to microencapsulate probiotic bacteria (Lactobacillus acidophilus 11073) using whey-protein-isolate (WPI)-octenyl-succinic-anhydride-starch (OSA-starch)-complex coacervates and to investigate the effects on probiotic bacterial viability during spray drying, simulated gastrointestinal digestion, thermal treatment and long-term storage. The optimum mixing ratio and pH for the preparation of WPI-OSA-starch-complex coacervates were determined to be 2:1 and 4.0, respectively. The combination of WPI and OSA starch under these conditions produced microcapsules with smoother surfaces and more compact structures than WPI-OSA starch alone, due to the electrostatic attraction between WPI and OSA starch. As a result, WPI-OSA-starch microcapsules showed significantly (p < 0.05) higher viability (95.94 ± 1.64%) after spray drying and significantly (p < 0.05) better protection during simulated gastrointestinal digestion, heating (65 °C/30 min and 75 °C/10 min) and storage (4/25 °C for 12 weeks) than WPI-OSA-starch microcapsules. These results demonstrated that WPI-OSA-starch-complex coacervates have excellent potential as a novel wall material for probiotic microencapsulation.


Assuntos
Probióticos , Soro do Leite , Cápsulas/química , Amido/química , Anidridos , Viabilidade Microbiana
9.
Angew Chem Int Ed Engl ; 62(34): e202305397, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37394690

RESUMO

Capacitive analogues of semiconductor diodes (CAPodes) present a new avenue for energy-efficient and nature-inspired next-generation computing devices. Here, we disclose the generalized concept for bias-direction-adjustable n- and p-CAPodes based on selective ion sieving. Controllable-unidirectional ion flux is realized by blocking electrolyte ions from entering sub-nanometer pores. The resulting CAPodes exhibit charge-storage characteristics with a high rectification ratio (96.29 %). The enhancement of capacitance is attributed to the high surface area and porosity of an omnisorbing carbon as counter electrode. Furthermore, we demonstrate the use of an integrated device in a logic gate circuit architecture to implement logic operations ('OR', 'AND'). This work demonstrates CAPodes as a generalized concept to achieve p-n and n-p analogue junctions based on selective ion electrosorption, provides a comprehensive understanding and highlights applications of ion-based diodes in ionologic architectures.

10.
Br J Haematol ; 198(4): 765-775, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35675486

RESUMO

Immune thrombocytopenia (ITP) is an acquired autoimmune disease, in which the imbalance of CD4+ T cell subsets play a key role in the pathogenesis. Since T cells highly depend on metabolism for their function, we hypothesized that T cell dysfunction may be due to intracellular metabolic reprogramming. We found that in ITP, T cell metabolism shifts from oxidative phosphorylation to glycolysis. Empagliflozin, a sodium-glucose cotransporter 2 inhibitor, has shown regulatory metabolic effects on proximal tubular epithelial cells and cardiac cells beyond glucose lowering. However, the effects of empagliflozin on T cells remain unknown. To further investigate the metabolic dysfunction of CD4+ T cells in ITP, we explored the effect of empagliflozin on CD4+ T-cell differentiation in ITP. Our results are the first to show that increased glycolysis in CD4+ T cells resulted in an unbalanced CD4+ T-cell population. Furthermore, empagliflozin can affect the differentiation of CD4+ T-cell subsets by inhibiting Th1 and Th17 cell populations while increasing Tregs. Empagliflozin appears to regulate CD4+ T cells through inhibiting the mTOR signal pathway. Considering these results, we propose that empagliflozin could be used as a potential therapeutic option for ITP by modulating metabolic reprogramming in CD4+ T cells.


Assuntos
Púrpura Trombocitopênica Idiopática , Compostos Benzidrílicos , Diferenciação Celular , Glucose/metabolismo , Glucosídeos , Humanos , Células Th17
11.
Br J Haematol ; 197(3): 367-372, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35288929

RESUMO

Primary immune thrombocytopenia (ITP) is an autoimmune haemorrhagic disease that could manifest with comorbid type 2 diabetes mellitus (T2DM). However, the exact impact of T2DM in patients with ITP remains uncertain. In this study, we performed a retrospective cohort study of 458 participants with ITP. The prevalence of T2DM was 7.6% in this population (35 patients), which was slightly lower than the Chinese nationwide prevalence of T2DM, calculated to be approximately 10.9%. The participants with pre-existing T2DM displayed a significantly higher response to therapy than those without T2DM (71% vs. 53%). Furthermore, in the T2DM cohort, the response rate reached 88% when metformin was included in the treatment regimen. This clinical evidence suggests that metformin therapy might improve the clinical outcomes of ITP.


Assuntos
Diabetes Mellitus Tipo 2 , Metformina , Adulto , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Humanos , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento
12.
Ann Hematol ; 101(4): 739-748, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35041051

RESUMO

Acquired aplastic anemia (AA) is an autoimmune disease characterized by hematopoietic stem and progenitor cell destruction in bone marrow. The non-classic human leukocyte class I antigen (HLA-) G interacts with multiple cell subsets, such as T cells and B cells. HLA-G exerts powerful immune suppression by binding with its receptors, immunoglobulin-like transcripts (ILTs). Here, we compared 46 AA patients and 28 healthy controls. Soluble HLA-G levels in bone marrow supernatants from AA patients were higher than controls. The proportion of bone marrow B cells was decreased and the ILT2-expressing cells among CD19+ cells were increased in AA patients. In addition, the percentage of mature B cells among marrow B cells was increased in AA patient, while the percentage of pro-B plus pre-B cells was decreased. More immature B cells and pro-B plus pre-B cells expressed ILT2 in AA patients than in controls, while mature B cells expressing ILT2 did not differ significantly. Functional studies demonstrated that high-level soluble HLA-G inhibited bone marrow B cell proliferation by interacting with ILT2 in AA, and was blocked by anti-HLA-G and anti-ILT2 monoclonal antibodies. Together, these results suggest that the abnormal decrease of pro-B plus pre-B cells in AA patients was related to the enhanced suppression by the excess HLA-G and ILT2 proteins. Therapeutic blockade of the HLA-G-ILT2 interaction may help to normalize bone marrow B cell proliferation.


Assuntos
Anemia Aplástica , Antígenos CD/metabolismo , Antígenos HLA-G , Receptor B1 de Leucócitos Semelhante a Imunoglobulina/metabolismo , Medula Óssea/metabolismo , Proliferação de Células , Humanos
13.
Med Sci Monit ; 28: e936830, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35903037

RESUMO

BACKGROUND In this study we aimed to establish a new transfer learning model based on noncontrast and thin-layer computed tomography (CT) scans to distinguish between malignant and benign solid lung nodules. MATERIAL AND METHODS CT images from 202 patients with 210 lesions (malignant: 127, benign: 83) manifesting as solid lung nodules from January 2016 to December 2020 from 3 institutions were retrospectively collected, and each nodule was histopathologically confirmed. Two experienced thoracic radiologists reviewed all images and determined the regions of interest (ROIs) in the three-dimensional (3D) images layer-by-layer. We divided the lesions and images into training and testing sets at a ratio of 7: 3. The Inception V3 model was pretrained by the training dataset. Five-fold cross-validation was used to choose the optimal model. Receiver operator characteristic curves (ROC curves) for methods to evaluate the performance of the models were drafted. RESULTS In the validation set, the AUC, accuracy, sensitivity, and specificity of Inception V3 model (lesion-level) were 0.999, 0.989, 0.983, and 1.0, respectively, which is higher than the image-level (0.997, 0.933, 0.922, and 0.948, respectively). The Inception V3 model (lesion-level) performed better than the image-level but there was no significant difference between the models (P>0.05). The ResNet50 model based on image level achieved AUC, accuracy, sensitivity, and specificity of 0.963, 0.926, 0.916, and 0.944, respectively, which is lower than that of Inception V3. CONCLUSIONS Our study developed a novel deep learning model based on noncontrast and thin-layer CT scans to classify benign vs malignant lung nodules, and the Inception V3 model greatly improved the differentiation accuracy and specificity.


Assuntos
Aprendizado Profundo , Neoplasias Pulmonares , Pulmão , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
14.
J Biol Chem ; 295(29): 10062-10075, 2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32518154

RESUMO

The human telomerase gene (hTERT) is repressed in most somatic cells. How transcription factors activate the hTERT promoter in its repressive chromatin environment is unknown. Here, we report that the ETS family protein ETS variant transcription factor 5 (ETV5) mediates epidermal growth factor (EGF)-induced hTERT expression in MCF10A cells. This activation required MYC proto-oncogene bHLH transcription factor (c-Myc) and depended on the chromatin state of the hTERT promoter. Using chromatinized bacterial artificial chromosome (BAC) reporters in human fibroblasts, we found that ETV5 and c-Myc/MYC-associated factor X (MAX) synergistically activate the hTERT promoter via two identical, but inverted, composite Ets/E-box motifs enclosing the core promoter. Mutations of Ets or E-box sites in either DNA motif abolished the activation and reduced or eliminated the synergism. ETV5 and c-Myc facilitated each other's binding to the hTERT promoter. ETV5 bound to the hTERT promoter in both telomerase-negative and -positive cells, but it activated the repressed hTERT promoter and altered histone modifications only in telomerase-negative cells. The synergistic ETV5/c-Myc activation disappeared when hTERT promoter repression became relieved because of the loss of distal regulatory elements in chimeric human/mouse BAC reporters. Our results suggest that the binding of c-Myc and ETS family proteins to the Ets/E-box motifs derepresses the hTERT promoter by inducing an active promoter configuration, providing a mechanistic insight into hTERT activation during tumorigenesis.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Regulação Enzimológica da Expressão Gênica , Proteínas Proto-Oncogênicas c-myc/metabolismo , Elementos de Resposta , Telomerase/biossíntese , Fatores de Transcrição/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Proteínas de Ligação a DNA/genética , Humanos , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-myc/genética , Telomerase/genética , Fatores de Transcrição/genética
15.
Ann Hematol ; 100(10): 2453-2462, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34269838

RESUMO

BACKGROUND: Primary immune thrombocytopenia (ITP) is an autoimmune disorder characterized by decreased platelet count. While corticosteroids are a useful first-line therapy for ITP patients, their long-term effectiveness is limited, and the determinants of corticosteroid sensitivity in ITP patients remain largely unknown. Sirtuin 1 (SIRT1), a member of the mammalian sirtuin family, is related to the anti-inflammatory effects of corticosteroids. Here, we investigate the contribution of the SIRT1 single-nucleotide polymorphisms (SNPs) rs12778366 and rs4746720 to ITP susceptibility. METHODS: We recruited 330 ITP patients and 309 healthy controls from Han population, and performed genotyping of SIRT1 rs12778366 and rs4746720 using a MassARRAY system. The results were validated in another 55 ITP patients from ethnic minorities. RESULTS: Using clinical data of patients and controls from Han polulation, including corticosteroid sensitivity, susceptibility, refractoriness, and severity, our results revealed that the CC/TC genotypes of SIRT1 rs12778366 were associated with a 2.034-fold increased risk of corticosteroid resistance compared to the homozygous major TT genotype (dominant, CC/TC vs. TT, OR = 2.034, 95% CI = 1.039-3.984, p = 0.038). In contrast, the CC/CT genotype of SIRT1 rs4746720 showed a 0.560-fold decreased risk of corticosteroid resistance (dominant, 95% CI = 0.321-0.976, OR = 0.560, p = 0.041). The C allele substitute in SIRT1 rs12778366 was significantly associated with the corticosteroid sensitivity of ITP patients (p = 0.021). The similar results were obtained in minority ITP patients. CONCLUSION: This study indicates that SIRT1 rs12778366 and rs4746720 may be genetic factors related to corticosteroid sensitivity in ITP patients.


Assuntos
Corticosteroides/uso terapêutico , Polimorfismo de Nucleotídeo Único , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Sirtuína 1/genética , Corticosteroides/farmacologia , Adulto , Resistência a Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/efeitos dos fármacos , Púrpura Trombocitopênica Idiopática/genética , Resultado do Tratamento
16.
J Clin Lab Anal ; 35(9): e23905, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34342048

RESUMO

INTRODUCTION: Hereditary human coagulation factor VII (FVII) deficiency is an inherited autosomal recessive hemorrhagic disease involving mutations in the F7 gene. The sites and types of F7 mutations may influence the coagulation activities of plasma FVII (FVII: C) and severity of hemorrhage symptoms. However, the specific mutations that impact FVII activity are not completely known. METHODS: We tested the coagulation functions and plasma activities of FVII in seven patients recruited from six families with hereditary FVII deficiency and sequenced the F7 gene of the patients and their families. Then, we analyzed the genetic information from the six families and predicted the structures of the mutated proteins. RESULTS: In this study, we detected 11 F7 mutations, including four novel mutations, in which the mutations p.Phe84Ser and p.Gly156Cys encoded the Gla and EGF domains of FVII, respectively, while the mutation p.Ser339Leu encoded the recognition site of the enzymatic protein and maintained the conformation of the catalytic domain structure. Meanwhile, the mutation in the 5' untranslated region (UTR) was closely associated with the mRNA regulatory sequence. CONCLUSION: We have identified novel genetic mutations and performed pedigree analysis that shed light on the pathogenesis of hereditary human coagulation FVII deficiency and may contribute to the development of treatments for this disease.


Assuntos
Deficiência do Fator VII/genética , Fator VII/genética , Mutação , Adolescente , Adulto , Sequência de Aminoácidos , Criança , Pré-Escolar , Análise Mutacional de DNA , Deficiência do Fator VII/patologia , Feminino , Humanos , Lactente , Masculino , Linhagem , Conformação Proteica , Homologia de Sequência de Aminoácidos
17.
Cultur Divers Ethnic Minor Psychol ; 27(4): 675-683, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34197144

RESUMO

Objective: Prior research documents numerous psychological and physiological benefits of implicit support particularly for Asians/Asian Americans. However, potential variation in how two different kinds of collectivism-Harmony and Convivial-shape support has been overlooked. Additionally, implicit support has largely been studied using quantitative approaches, whereas qualitative methods may best illuminate how implicit support is used in everyday life. The present mixed-methods investigation aims to better understand implicit support "in practice" and to unpack previously overlooked nuances between different subsets of collectivism in implicit support processes. Method: We collected qualitative accounts of implicit support interactions from 216 female participants (U.S. Whites, U.S. Latinas, U.S. Asians, Mexican, Taiwanese) who were prompted to describe an implicit support experience and then quantitatively assess its helpfulness. Results: Qualitative analysis using a thematic analysis approach identified three subcategories of implicit support (traditional, semi-disclosure, non-verbal cues). Cultural patterns emerged in how implicit support was used across different groups that align with high-context and low-context communication theories and cultural values. Conclusions: The current research highlights the benefit of qualitative approaches to understanding nuanced support processes, and the need to study culture beyond the individualism-collectivism dichotomy. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Assuntos
Asiático , Individualidade , Feminino , Hispânico ou Latino , Humanos , México , Taiwan
18.
Biotechnol Bioeng ; 117(9): 2816-2826, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32449788

RESUMO

Homologous recombination over large genomic regions is difficult to achieve due to low efficiencies. Here, we report the successful engineering of a humanized mTert allele, hmTert, in the mouse genome by replacing an 18.1-kb genomic region around the mTert gene with a recombinant fragment of over 45.5 kb, using homologous recombination facilitated by the Crispr/Cas9 technology, in mouse embryonic stem cells (mESCs). In our experiments, with DNA double-strand breaks (DSBs) generated by Crispr/Cas9 system, the homologous recombination efficiency was up to 11% and 16% in two mESC lines TC1 and v6.5, respectively. Overall, we obtained a total of 27 mESC clones with heterozygous hmTert/mTert alleles and three clones with homozygous hmTert alleles. DSBs induced by Crispr/Cas9 cleavages also caused high rates of genomic DNA deletions and mutations at single-guide RNA target sites. Our results indicated that the Crispr/Cas9 system significantly increased the efficiency of homologous recombination-mediated gene editing over a large genomic region in mammalian cells, and also caused frequent mutations at unedited target sites. Overall, this strategy provides an efficient and feasible way for manipulating large chromosomal regions.


Assuntos
Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Recombinação Homóloga/genética , Animais , Quebras de DNA de Cadeia Dupla , Humanos , Camundongos , Plasmídeos/genética
19.
Jpn J Clin Oncol ; 50(12): 1470-1474, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-32845005

RESUMO

Ovarian cancer is prone to recurrence and chemotherapy resistance. Ovarian tumours of some patients have been positive for anaplastic lymphoma kinase fusion gene expression (ALK+). Preclinical studies indicate that anaplastic lymphoma kinase inhibitor can suppress the growth of ovarian cancer cells and transplantation tumours. Here, we present a patient with metastatic ALK+ high-grade serous ovarian cancer that testing positive for EML4-ALK (microtubule-associated protein-like 4 gene, fused to the anaplastic lymphoma kinase gene), experienced dramatic benefit after administration of the anaplastic lymphoma kinase inhibitor alectinib. This is the first clinical evidence that treatment with alectinib may provide a personalized maximum benefit for patients with high-grade serous ovarian cancer who are positive for EML4-ALK.


Assuntos
Carbazóis/uso terapêutico , Carcinoma Epitelial do Ovário/tratamento farmacológico , Proteínas de Fusão Oncogênica/genética , Neoplasias Ovarianas/tratamento farmacológico , Piperidinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Quinase do Linfoma Anaplásico/genética , Carcinoma Epitelial do Ovário/genética , Feminino , Humanos , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Neoplasias Ovarianas/genética , Resultado do Tratamento
20.
Cultur Divers Ethnic Minor Psychol ; 26(3): 280-294, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31613122

RESUMO

OBJECTIVES: First-generation college students commonly experience financial, academic, and personal challenges that are exacerbated by a cultural mismatch between independent university settings and interdependent family environments. There is a paucity of research on the influence of cultural norms, including cultural mismatch, on first-generation college students' coping and help-seeking behaviors. The present research explored how cultural norms affect coping and help seeking for academic, financial, and psychological problems among diverse first-generation college students. METHOD: Eleven individual interviews were conducted to obtain pilot data, and 8 group interviews (n = 60) were conducted to examine cultural norms, relational concerns, coping, and social support. These same 71 participants (51% Ethnic Minority; 49% White; 70% female) completed a background survey (e.g., demographics, use of resources, coping, and family obligation). RESULTS: Most students were self-reliant and underutilized social support because of concerns about negatively affecting close relationships; these relational concerns included burdening others, being judged by others, and making matters worse. Concerns about face loss and group harmony were heightened among ethnic minority students. Despite limited quantitative evidence for White-Ethnic Minority differences in coping and psychological and academic functioning, minority students reported higher levels of family obligation. CONCLUSIONS: Results revealed a mismatch between hard independence (being self-reliant, resilient, and emotionally tough) and soft independence (being self-expressive, pursuing personal interests, and gaining a sense of freedom) and illuminate how relational concerns hinder help seeking among first-generation college students. These findings support culturally tailoring outreach efforts to address norms that promote self-reliance and the underutilization of services. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Adaptação Psicológica , Comportamento de Busca de Ajuda , Grupos Minoritários/psicologia , Autoeficácia , Apoio Social , Estudantes/psicologia , Etnicidade/psicologia , Feminino , Humanos , Masculino , Inquéritos e Questionários , Universidades , Adulto Jovem
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