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1.
Proc Natl Acad Sci U S A ; 119(14): e2122217119, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35344434

RESUMO

SignificanceA clear mechanistic understanding of metformin's antidiabetic effects is lacking. This is because suprapharmacological concentrations of metformin have been used in most studies. Using mouse models and human primary hepatocytes, we show that metformin, at clinically relevant doses, suppresses hepatic glucose production by activating a conserved regulatory pathway encompassing let-7, TET3, and a fetal isoform of hepatocyte nuclear factor 4 alpha (HNF4α). We demonstrate that metformin no longer has potent antidiabetic actions in a liver-specific let-7 loss-of-function mouse model and that hepatic delivery of let-7 ameliorates hyperglycemia and improves glucose homeostasis. Our results thus reveal an important role of the hepatic let-7/TET3/HNF4α axis in mediating the therapeutic effects of metformin and suggest that targeting this axis may be a potential therapeutic for diabetes.


Assuntos
Hiperglicemia , Metformina , Animais , Modelos Animais de Doenças , Glucose/metabolismo , Hepatócitos/metabolismo , Hiperglicemia/metabolismo , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Fígado/metabolismo , Metformina/uso terapêutico , Camundongos
2.
J Mol Cell Cardiol ; 194: 16-31, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38821243

RESUMO

BACKGROUND: Hypoxia-induced pulmonary artery hypertension (HPH) is a complication of chronic hypoxic lung disease and the third most common type of pulmonary artery hypertension (PAH). Epigenetic mechanisms play essential roles in the pathogenesis of HPH. N6-methyladenosine (m6A) is an important modified RNA nucleotide involved in a variety of biological processes and an important regulator of epigenetic processes. To date, the precise role of m6A and regulatory molecules in HPH remains unclear. METHODS: HPH model and pulmonary artery smooth muscle cells (PASMCs) were constructed from which m6A changes were observed and screened for AlkB homolog 5 (Alkbh5). Alkbh5 knock-in (KI) and knock-out (KO) mice were constructed to observe the effects on m6A and evaluate right ventricular systolic pressure (RVSP), left ventricular and septal weight [RV/(LV + S)], and pulmonary vascular remodeling in the context of HPH. Additionally, the effects of Alkbh5 knockdown using adenovirus were examined in vitro on m6A, specifically in PASMCs with regard to proliferation, migration and cytochrome P450 1A1 (Cyp1a1) mRNA stability. RESULTS: In both HPH mice lung tissues and hypoxic PASMCs, a decrease in m6A was observed, accompanied by a significant up-regulation of Alkbh5 expression. Loss of Alkbh5 attenuated the proliferation and migration of hypoxic PASMCs in vitro, with an associated increase in m6A modification. Furthermore, Alkbh5 KO mice exhibited reduced RVSP, RV/(LV + S), and attenuated vascular remodeling in HPH mice. Mechanistically, loss of Alkbh5 inhibited Cyp1a1 mRNA decay and increased its expression through an m6A-dependent post-transcriptional mechanism, which hindered the proliferation and migration of hypoxic PASMCs. CONCLUSION: The current study highlights the loss of Alkbh5 impedes the proliferation and migration of PASMCs by inhibiting post-transcriptional Cyp1a1 mRNA decay in an m6A-dependent manner.

3.
Br J Cancer ; 131(1): 1-10, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38514762

RESUMO

In current clinical practice, radiotherapy (RT) is prescribed as a pre-determined total dose divided over daily doses (fractions) given over several weeks. The treatment response is typically assessed months after the end of RT. However, the conventional one-dose-fits-all strategy may not achieve the desired outcome, owing to patient and tumor heterogeneity. Therefore, a treatment strategy that allows for RT dose personalization based on each individual response is preferred. Multiple strategies have been adopted to address this challenge. As an alternative to current known strategies, artificial intelligence (AI)-derived mechanism-independent small data phenotypic medicine (PM) platforms may be utilized for N-of-1 RT personalization. Unlike existing big data approaches, PM does not engage in model refining, training, and validation, and guides treatment by utilizing prospectively collected patient's own small datasets. With PM, clinicians may guide patients' RT dose recommendations using their responses in real-time and potentially avoid over-treatment in good responders and under-treatment in poor responders. In this paper, we discuss the potential of engaging PM to guide clinicians on upfront dose selections and ongoing adaptations during RT, as well as considerations and limitations for implementation. For practicing oncologists, clinical trialists, and researchers, PM can either be implemented as a standalone strategy or in complement with other existing RT personalizations. In addition, PM can either be used for monotherapeutic RT personalization, or in combination with other therapeutics (e.g. chemotherapy, targeted therapy). The potential of N-of-1 RT personalization with drugs will also be presented.


Assuntos
Neoplasias , Medicina de Precisão , Humanos , Medicina de Precisão/métodos , Neoplasias/radioterapia , Inteligência Artificial , Fenótipo , Dosagem Radioterapêutica
4.
Int J Mol Sci ; 25(6)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38542262

RESUMO

Graves' ophthalmopathy (GO), or thyroid eye disease (TED), is the most frequent extrathyroidal manifestation of Graves' disease (GD). Inflammation and subsequent aberrant tissue remodeling with fibrosis are important pathogenesis. There are many proposed mechanisms and molecular pathways contributing to tissue remodeling and fibrosis in GO, including adipogenesis, fibroblast proliferation and myofibroblasts differentiation, oxidative stress, endoplasmic reticulum (ER) stress, hyaluronan (HA) and glycosaminoglycans (GAGs) accumulation in the extracellular matrix (ECM) and new concepts of epigenetics modification, such as histone modification, DNA methylation, non-coding RNAs, and gut microbiome. This review summarizes the current understanding of ECM proteins and associated tissue remodeling in the pathogenesis and potential mediators for the treatment of GO.


Assuntos
Doença de Graves , Oftalmopatia de Graves , Humanos , Oftalmopatia de Graves/genética , Oftalmopatia de Graves/metabolismo , Órbita/metabolismo , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Doença de Graves/metabolismo , Fibrose
5.
Int Heart J ; 65(1): 4-12, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38296578

RESUMO

Neoatherosclerosis is a major cause of stent failure after percutaneous coronary intervention. Metabolism such as hyperuricemia is associated with in-stent restenosis (ISR). However, the association between serum uric acid (sUA) levels and in-stent neoatherosclerosis (ISNA) has never been validated.A total of 216 patients with 220 ISR lesions who had undergone optical coherence tomography (OCT) of culprit stents were included in this study. According to their sUA levels, eligible patients were divided into two groups [normal-sUA group: sUA < 7 mg/dL, n = 126, and high-sUA group: sUA ≥ 7 mg/dL, n = 90]. OCT findings were analyzed and compared between the normal- and high-sUA groups.The incidence of ISNA (63.0% versus 43.0%, P = 0.004) was significantly higher in the high-sUA group than in the normal-sUA group. Lipid plaques (66.3% versus 43.0%, P < 0.001) and thin-cap fibroatheroma (38.0% versus 18.0%, P = 0.001) were observed more frequently in the restenotic tissue structure in patients in the high-sUA group than in those in the normal-sUA group. Meanwhile, univariate (OR: 1.208, 95% CI: 1.037-1.407; P = 0.015) and multivariate (OR: 1.254, 95% CI: 1.048-1.501; P = 0.013) logistic regression analyses indicated that sUA levels were an independent risk factor for ISNA after adjusting for relevant risk factors.The high-sUA levels were an independent risk factor for the occurrence of neoatherosclerosis in patients with ISR via OCT.


Assuntos
Aterosclerose , Reestenose Coronária , Intervenção Coronária Percutânea , Placa Aterosclerótica , Humanos , Ácido Úrico , Reestenose Coronária/etiologia , Reestenose Coronária/complicações , Placa Aterosclerótica/complicações , Stents/efeitos adversos , Aterosclerose/etiologia , Tomografia de Coerência Óptica/métodos , Intervenção Coronária Percutânea/efeitos adversos , Constrição Patológica/patologia , Vasos Coronários/patologia
6.
FASEB J ; 36(11): e22602, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36250925

RESUMO

Chronic inflammation is one of the definite factors leading to the occurrence and development of tumors, including prostate cancer (PCa). The androgen receptor (AR) pathway is essential for PCa tumorigenesis and inflammatory response. However, little is known about the AR-regulated NACHT, LRR, and PYD domain-containing protein 3 (NLRP3) inflammasome pathway in human PCa. In this study, we explored the expression of inflammatory cytokine and AR in high-grade PCa and observed that NLRP3 inflammasome-associated genes were upregulated in high-grade PCa compared with that in low-grade PCa and benign prostatic hyperplasia and were associated with AR expression. In addition, we identified circAR-3-a circRNA derived from the AR gene-which is involved in the AR-regulated inflammatory response and cell proliferation by activating the NLRP3 inflammatory pathway. While circAR-3 overexpression promoted cell proliferation and the inflammatory response, its depletion induced opposite effects. Mechanistically, we noted that circAR-3 mediated the acetylation modification of NLRP3 by KAT2B and then promoted NLRP3 inflammasome complex subcellular distribution and assembly. Disturbing NLRP3 acetylation or blocking inflammasome assembly with an inhibitor suppressed the progression of PCa xenograft tumors. Our findings provide the first evidence that targeting NLRP3 acetylation or inflammasome assembly may be effective in inhibiting PCa progression.


Assuntos
Neoplasias da Próstata , Receptores Androgênicos , Acetilação , Citocinas/metabolismo , Humanos , Inflamassomos/genética , Inflamassomos/metabolismo , Masculino , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Neoplasias da Próstata/metabolismo , RNA Circular , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-38030142

RESUMO

ABSTRACT: The mechanism of in-stent restenosis (ISR) remains elusive, and in-stent neoatherosclerosis (ISNA) may hold siginificant pathophysiological implications. Nevertheless, the correlation between ISNA and the progression of untreated coronary segments affected by native atherosclerosis remains incompletely investigated. This study enrolled 225 patients diagnosed with coronary heart disease and multivessel disease (MVD). These patients underwent successful percutaneous coronary intervention (PCI) and intraoperative placement of drug-eluting stent (DES), followed by optical coherence tomography (OCT) assessment of the culprit stent. The mechanism of ISR was emamined through qualitative and quantitative analysis of OCT imaging. A significantly higher proportion of patients in the ISR with non-target lesion progression (N-TLP) group exhibited lipid plaque formation compared to the ISR without N-TLP group (69.0% versus 39.8%, P < 0.001). The incidence of thin-cap fibroatheroma (TCFA) (33.3% versus 11.4%, P = 0.001) and ISNA (60.7% versus 38.6%, P < 0.001) was markedly elevated in the ISR with N-TLP group compared to the ISR without N-TLP group. Regarding manifestations, heterogeneous hyperplasia was predominantly observed in the ISR with N-TLP group (76.2% versus 38.6%, P < 0.001), while homogeneous hyperplasia was primarily presented in the ISR without N-TLP group (61.4% versus 23.8%, P < 0.001). Patients displaying notable progression of naturally occurring atherosclerosis manifest histomorphological features of ISR, primarily characterized by heterogeneous intimal hyperplasia and a higher prevalence of ISNA. In contrast, patients without substantial progression of naturally occurring atherosclerosis exhibit histomorphologic features of ISR primarily characterized by homogeneous intimal hyperplasia.

8.
BMC Cardiovasc Disord ; 23(1): 585, 2023 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-38012550

RESUMO

In an era of increasing need for precision medicine, machine learning has shown promise in making accurate acute myocardial infarction outcome predictions. The accurate assessment of high-risk patients is a crucial component of clinical practice. Type 2 diabetes mellitus (T2DM) complicates ST-segment elevation myocardial infarction (STEMI), and currently, there is no practical method for predicting or monitoring patient prognosis. The objective of the study was to compare the ability of machine learning models to predict in-hospital mortality among STEMI patients with T2DM. We compared six machine learning models, including random forest (RF), CatBoost classifier (CatBoost), naive Bayes (NB), extreme gradient boosting (XGBoost), gradient boosting classifier (GBC), and logistic regression (LR), with the Global Registry of Acute Coronary Events (GRACE) risk score. From January 2016 to January 2020, we enrolled patients aged > 18 years with STEMI and T2DM at the Affiliated Hospital of Zunyi Medical University. Overall, 438 patients were enrolled in the study [median age, 62 years; male, 312 (71%); death, 42 (9.5%]). All patients underwent emergency percutaneous coronary intervention (PCI), and 306 patients with STEMI who underwent PCI were enrolled as the training cohort. Six machine learning algorithms were used to establish the best-fit risk model. An additional 132 patients were recruited as a test cohort to validate the model. The ability of the GRACE score and six algorithm models to predict in-hospital mortality was evaluated. Seven models, including the GRACE risk model, showed an area under the curve (AUC) between 0.73 and 0.91. Among all models, with an accuracy of 0.93, AUC of 0.92, precision of 0.79, and F1 value of 0.57, the CatBoost model demonstrated the best predictive performance. A machine learning algorithm, such as the CatBoost model, may prove clinically beneficial and assist clinicians in tailoring precise management of STEMI patients and predicting in-hospital mortality complicated by T2DM.


Assuntos
Diabetes Mellitus Tipo 2 , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Infarto do Miocárdio com Supradesnível do Segmento ST/etiologia , Medição de Risco/métodos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Intervenção Coronária Percutânea/efeitos adversos , Teorema de Bayes , Mortalidade Hospitalar , Aprendizado de Máquina
9.
Lipids Health Dis ; 22(1): 66, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37210547

RESUMO

BACKGROUND: Myocardial infarction (MI) and post-MI-heart failure (pMIHF) are a major cause of death worldwide, however, the underlying mechanisms of pMIHF from MI are not well understood. This study sought to characterize early lipid biomarkers for the development of pMIHF disease. METHODS: Serum samples from 18 MI and 24 pMIHF patients were collected from the Affiliated Hospital of Zunyi Medical University and analyzed using lipidomics with Ultra High Performance Liquid Chromatography and Q-Exactive High Resolution Mass Spectrometer. The serum samples were tested by the official partial least squares discriminant analysis (OPLS-DA) to find the differential expression of metabolites between the two groups. Furthermore, the metabolic biomarkers of pMIHF were screened using the subject operating characteristic (ROC) curve and correlation analysis. RESULTS: The average age of the 18 MI and 24 pMIHF participants was 57.83 ± 9.28 and 64.38 ± 10.89 years, respectively. The B-type natriuretic peptide (BNP) level was 328.5 ± 299.842 and 3535.96 ± 3025 pg/mL, total cholesterol(TC) was 5.59 ± 1.51 and 4.69 ± 1.13 mmol/L, and blood urea nitrogen (BUN) was 5.24 ± 2.15 and 7.20 ± 3.49 mmol/L, respectively. In addition, 88 lipids, including 76 (86.36%) down-regulated lipids, were identified between the patients with MI and pMIHF. ROC analysis showed that phosphatidylethanolamine (PE) (12:1e_22:0) (area under the curve [AUC] = 0.9306) and phosphatidylcholine (PC) (22:4_14:1) (AUC = 0.8380) could be potential biomarkers for the development of pMIHF. Correlation analysis showed that PE (12:1e_22:0) was inversely correlated with BNP and BUN, but positively correlated with TC. In contrast, PC (22:4_14:1) was positively associated with both BNP and BUN, and was negatively associated with TC. CONCLUSIONS: Several lipid biomarkers were identified that could potentially be used to predict and diagnose patients with pMIHF. PE (12:1e_22:0) and PC (22:4_14:1) could sufficiently differentiate between patients with MI and pMIHF.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio , Humanos , Pessoa de Meia-Idade , Idoso , Lipidômica , Fosfatidilcolinas , Fosfatidiletanolaminas , Biomarcadores
10.
Molecules ; 28(14)2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37513480

RESUMO

To study the use of partial or total potassium bicarbonate (PBC) to replace sodium tripolyphosphate (STPP) on reduced-phosphate silver carp batters, all the batters were composed of silver carp surimi, pork back fat, ice water, spices, sugar, and sodium chloride. Therein, the sample of T1 contained 4 g/kg STPP; T2 contained 1 g/kg PBC, 3 g/kg STPP; T3 contained 2 g/kg PBC, 2 g/kg STPP; T4 contained 3 g/kg PBC, 1 g/kg STPP; T5 contained 4 g/kg PBC, and they were all produced using a bowl chopper. The changes in pH, whiteness, water- and oil-holding capacity, gel and rheological properties, as well as protein conformation were investigated. The pH, cooking yield, water- and oil-holding capacity, texture properties, and the G' values at 90 °C of the reduced-phosphate silver carp batters with PBC significantly increased (p < 0.05) compared to the sample without PBC. Due to the increasing pH and enhanced ion strength, more ß-sheet and ß-turns structures were formed. Furthermore, by increasing PBC, the pH significantly increased (p < 0.05) and the cooked silver carp batters became darkened. Meanwhile, more CO2 was generated, which destroyed the gel structure, leading the water- and oil-holding capacity, texture properties, and G' values at 90 °C to be increased and then decreased. Overall, using PBC partial as a substitute of STPP enables reduced-phosphate silver carp batter to have better gel characteristics and water-holding capacity by increasing its pH and changing its rheology characteristic and protein conformation.


Assuntos
Carpas , Água , Animais , Água/química , Fosfatos , Reologia
11.
Am J Physiol Regul Integr Comp Physiol ; 323(4): R484-R495, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35993561

RESUMO

Stress plays a major role in the pathogenesis of many diseases. Central neuropeptide Y (NPY) counteracts the biological actions of corticotropin-releasing factor (CRF) and attenuates stress responses. Intracerebroventricular (ICV) administration of NPY significantly antagonized the inhibitory effects of chronic complicated stress (CCS) on gastrointestinal (GI) dysmotility in rats. However, ICV administration is an invasive technique. The effect of intranasal administration of NPY on the hypothalamus-pituitary-adrenal (HPA) axis and GI motility in CCS conditions have not been studied, and the inhibitory mechanism of NPY on CRF through the γ-aminobutyric acid (GABA)A receptor needs to be further investigated. A CCS rat model was set up, and NPY was intranasally administered every day before the stress loading. Furthermore, ICV administration of a GABAA receptor antagonist was performed daily. Hypothalamic CRF and NPY expressions were evaluated, serum corticosterone and NPY levels were analyzed, and colonic motor functions were assessed. CCS rats showed significantly increased CRF expression and corticosterone levels, which resulted in enhanced colonic motor functions. Intranasal NPY significantly increased hypothalamic NPY mRNA expression and reduced CRF mRNA expression and plasma corticosterone levels, helping to restore colonic motor functions. However, ICV administration of the GABAA receptor antagonist significantly abolished these effects induced by NPY. In conclusion, intranasal administration of NPY upregulates the hypothalamic NPY system. NPY may, through the GABAA receptor, significantly antagonize overexpressed central CRF and attenuate HPA axis activity in CCS conditions, influencing and helping to restore colonic motor function.


Assuntos
Hormônio Liberador da Corticotropina , Neuropeptídeo Y , Administração Intranasal , Animais , Proteínas de Transporte/metabolismo , Corticosterona , Hormônio Liberador da Corticotropina/metabolismo , Sistema Hipotálamo-Hipofisário , Masculino , Neuropeptídeo Y/metabolismo , Sistema Hipófise-Suprarrenal/metabolismo , RNA Mensageiro/metabolismo , Ratos , Receptores de GABA-A/metabolismo , Receptores de Neuropeptídeo Y/metabolismo , Ácido gama-Aminobutírico
12.
Cancer Cell Int ; 22(1): 109, 2022 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-35248043

RESUMO

BACKGROUND: Abnormal expression of splicing factor 3A subunit 3 (SF3A3), a component of the spliceosome, has been confirmed to be related to the occurrence and development of various cancers. However, the expression and function of SF3A3 in bladder cancer (BC) remains unclear. METHODS: The SF3A3 mRNA and protein level were measured in clinical samples and cell lines by quantitative real-time PCR, Western blot and immunofluorescence staining. Evaluate the clinical correlation between SF3A3 expression and clinicopathological characteristics through statistical analysis in BC patients. The function of SF3A3 in BC cells was determined in vitro using MTT and colony analysis. Co-immunoprecipitation (CoIP) assay was used to detected E2F6 and KDM5C interaction. Luciferase reporter and chromatin immunoprecipitation (ChIP) were used to examine the relationship between E2F6/KDM5C and SF3A3 expression. RESULTS: In the present study, we demonstrated that expression of SF3A3 was elevated in BC tissue compared to the normal bladder tissue. Importantly, the upregulation of SF3A3 in patients was correlated with poor prognosis. Additionally, overexpression of SF3A3 promoted while depletion of SF3A3 reduced the growth of BC cells in vivo and in vitro. Data from the TCGA database and clinical samples revealed that hypomethylation of the DNA promoter leads to high expression of SF3A3 in BC tissue. We found that upregulation of lysine-specific demethylase 5C (KDM5C) promotes SF3A3 expression via hypomethylation of the DNA promoter. The transcription factor E2F6 interacts with KDM5C, recruits KDM5C to the SF3A3 promoter, and demethylates the GpC island of H3K4me2, leading to high SF3A3 expression and BC progression. CONCLUSIONS: The results demonstrated that depletion of the KDM5C/SF3A3 prevents the growth of BC in vivo and in vitro. The E2F6/KDM5C/SF3A3 pathway may be a potential therapeutic target for BC treatment.

13.
Neoplasma ; 69(2): 464-473, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35068159

RESUMO

Neuroblastoma (NB) is one of the most common extracranial malignant solid tumors in childhood, and over 90% of NBs are diagnosed in children under the age of 10 years old. For patients between 14 and 18 years old or older than 18 years, due to the rarity of NB, few studies have been performed in this population. Defined "adolescent cases" as individuals in 14-18 years old and "adult cases" as older than 18 years old, we reported five NB cases of adolescents and adults in our hospital. 137 cases presented a review of published literature on this topic. Clinicopathological factors and treatment modalities used of the 142 patients were assessed for their prognostic value. Better outcomes were found in adolescent patients rather than adult patients (p=0.012). Patients diagnosed with neuroblastoma or ganglioneuroblastoma (nodular type) (p=0.006) and with distant metastasis (p<0.001) were characterized by poor outcomes. Distant metastasis was an independent adverse influencing factor for overall survival in adolescent and adult NB patients. Regarding treatment modalities, complete surgical resection was a significant factor improving the survival for such patients (p<0.001). For patients with distant metastasis, a significantly longer progression-free survival with chemotherapy than without chemotherapy (p=0.038), whereas chemotherapy did not show an advantage on patients with localized disease (p=0.039). The prognosis of NB in adolescent and adult patients was worse than that in children. These two groups also showed heterogeneity in clinical factors, genetic factors, and treatment tolerance. The rarity of adolescent and adult NB can lead to misdiagnosis and incorrect management. Further optimization of chemotherapy regimens and dosage for adolescent and adult NB patients is needed. The anti-GD2 immunotherapy may be an effective approach for treatment.


Assuntos
Neuroblastoma , Adolescente , Adulto , Criança , Humanos , Imunoterapia , Lactente , Neuroblastoma/tratamento farmacológico , Neuroblastoma/terapia , Prognóstico
14.
Opt Express ; 29(7): 11268-11276, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33820242

RESUMO

We report GaSb-based laser diodes (LDs) grown on on-axis (001) Si substrates and emitting at 2.3 µm. Two series of LDs were studied and compared. For the first series, a GaAs-based buffer layer was first grown by metal organic chemical vapor deposition (MOCVD) before growing the laser heterostructure by molecular-beam epitaxy (MBE). For the second series, a MOCVD GaSb buffer layer was added between the MOCVD GaAs buffer layer and the MBE laser heterostructure. Both series of LDs exhibited threshold currents in the 50-100 mA range and several mW output power at room temperature. They demonstrated continuous wave operation (CW) up to 70°C (set-up limited) without thermal rollover. Broad area LDs exhibited record threshold-current densities in the 250-350 A.cm-2 range for the second series of LDs, in spite of cracks that appeared during device processing. These results show that the design and fabrication steps of the buffer-layer stacks are critical issues in the epitaxial integration of GaSb-based optoelectronic devices on Si substrates and offer room for much performance improvement.

15.
Opt Express ; 29(9): 13193-13203, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33985059

RESUMO

In this paper, we demonstrate an efficient and easy fabrication method for whispering-gallery-mode (WGM) manipulation and report the first electrically driven single-mode quantum dot micro-ring (QDMR) lasers. Using self-assembled InAs/InAlGaAs QD active layers with deeply etched azimuthal gratings, continuous-wave (CW) lasing with controllable single-mode emission wavelengths covering 1300 nm to 1370 nm has been achieved. A record-high side-mode-suppression-ratio (SMSR) value of 49 dB is obtained. These QDMR lasers exhibit excellent single-mode lasing stabilities over the current and temperature tuning range with a thermal tunability of 0.092 nm/°C. The concept is applicable to other wavelength bands depending on the gain spectrum, demonstrating a feasible solution in realizing energy-efficient and densely integrated photonic building blocks.

16.
Cancer Cell Int ; 21(1): 323, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34183010

RESUMO

BACKGROUND: The dysfunction of myc-related zinc finger protein (MAZ) has been proven to contribute to tumorigenesis and development of multiple cancer types. However, the biological roles and clinical significance of MAZ in clear cell renal carcinoma (ccRCC) remain unclear. METHODS: MAZ expression was examined in ccRCC and normal kidney tissue by quantitative real-time PCR and Western blot. Statistical analysis was used to evaluate the clinical correlation between MAZ expression and clinicopathological characteristics to determine the relationship between MAZ expression and the survival of ccRCC patients. The biological roles of MAZ in cells were investigated in vitro using MTT and colony assays. Luciferase reporter assays and chromatin immunoprecipitation (ChIP) were used to investigate the relationship between MAZ and its potential downstream signaling molecules. RESULTS: MAZ expression is elevated in ccRCC tissues, and higher levels of MAZ were correlated with poor survival of patients with ccRCC. MAZ upregulation elevates the proliferation ability of ccRCC cells in vitro, whereas silencing MAZ represses this ability. Our results further reveal that MAZ promotes cell growth, which is dependent on ERK signaling. Importantly, we found that MAZ positively regulates MAP2K2 expression in ccRCC cells. Mechanistically, MAZ binds to the MAP2K2 promoter and increases MAP2K2 transcription. Furthermore, MAP2K2 levels were shown to be increased in ccRCC tissues and to be associated with a poor prognosis of ccRCC patients. MAP2K2 upregulation activates the ERK signaling pathway and promotes ccRCC progression. CONCLUSION: These results reveal that the MAZ/MAP2K2/ERK signaling axis plays a crucial role in promoting ccRCC progression, which suggests the potential therapeutic utility of MAZ in ccRCC.

17.
Mol Cell Proteomics ; 18(Suppl 1): S109-S117, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30126978

RESUMO

Semen samples from men after a short ejaculatory abstinence show improved sperm quality and result in increased pregnancy rates, but the underlying mechanisms remain unclear. Herein, we report that ejaculates from short (1-3 h) compared with long (3-7 days) periods of abstinence showed increases in motile sperm count, sperm vitality, normal sperm morphology, acrosome reaction capacity, total antioxidant capacity, sperm mitochondrial membrane potential, high DNA stainability, and a decrease in the sperm DNA fragmentation index (p, < 0.05). Sperm proteomic analysis showed 322 differentially expressed proteins (minimal fold change of ±1.5 or greater and p, < 0.05), with 224 upregulated and 98 downregulated. These differentially expressed proteins are profoundly involved in specific cellular processes, such as motility and capacitation, oxidative stress, and metabolism. Interestingly, protein trimethyllysine modification was increased, and butyryllysine, propionyllysine, and malonyllysine modifications were decreased in ejaculates from a short versus, long abstinence (p, < 0.05). Finally, the rates of implantation, clinical pregnancy, and live births from in vitro, fertilization treatments were significantly increased in semen samples after a short abstinence. Our study provides preliminary mechanistic insights into improved sperm quality and pregnancy outcomes associated with spermatozoa retrieved after a short ejaculatory abstinence.


Assuntos
Ejaculação/fisiologia , Fertilização in vitro , Proteoma/metabolismo , Reprodução/fisiologia , Abstinência Sexual/fisiologia , Espermatozoides/metabolismo , Adulto , Transferência Embrionária , Feminino , Humanos , Masculino , Contagem de Espermatozoides , Motilidade dos Espermatozoides/fisiologia
18.
Int J Mol Sci ; 22(6)2021 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-33799469

RESUMO

Transforming growth factor-ß1 (TGF-ß1)-induced myofibroblast transdifferentiation from orbital fibroblasts is known to dominate tissue remodeling and fibrosis in Graves' ophthalmopathy (GO). However, the signaling pathways through which TGF-ß1 activates Graves' orbital fibroblasts remain unclear. This study investigated the role of the mitogen-activated protein kinase (MAPK) pathway in TGF-ß1-induced myofibroblast transdifferentiation in human Graves' orbital fibroblasts. The MAPK pathway was assessed by measuring the phosphorylation of p38, c-Jun N-terminal kinase (JNK), and extracellular-signal-regulated kinase (ERK) by Western blots. The expression of connective tissue growth factor (CTGF), α-smooth muscle actin (α-SMA), and fibronectin representing fibrogenesis was estimated. The activities of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) responsible for extracellular matrix (ECM) metabolism were analyzed. Specific pharmacologic kinase inhibitors were used to confirm the involvement of the MAPK pathway. After treatment with TGF-ß1, the phosphorylation levels of p38 and JNK, but not ERK, were increased. CTGF, α-SMA, and fibronectin, as well as TIMP-1 and TIMP-3, were upregulated, whereas the activities of MMP-2/-9 were inhibited. The effects of TGF-ß1 on the expression of these factors were eliminated by p38 and JNK inhibitors. The results suggested that TGF-ß1 could induce myofibroblast transdifferentiation in human Graves' orbital fibroblasts through the p38 and JNK pathways.


Assuntos
Transdiferenciação Celular/genética , MAP Quinase Quinase 4/genética , Fator de Crescimento Transformador beta1/genética , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Actinas/genética , Células Cultivadas , Fator de Crescimento do Tecido Conjuntivo/genética , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibronectinas/genética , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Humanos , Miofibroblastos/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Fator de Crescimento Transformador beta1/farmacologia
19.
Opt Express ; 28(12): 18172-18179, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-32680018

RESUMO

Realization of fully integrated silicon photonics has been handicapped by the lack of a reliable and efficient III-V light source on Si. Specifically, electrically pumped continuous wave (CW) lasing and operation sustainable at high temperatures are critical for practical applications. Here, we present the first electrically pumped room temperature (RT) CW lasing results of 1.55 µm quantum dash (QDash) lasers directly grown on patterned on-axis (001) Si using metal organic chemical vapor deposition (MOCVD). Adopting a dash-in-well structure as the active medium, the growth of QDash was optimized on an InP on Si template. Incorporating the advantages of the optimized material growth and device fabrication, good laser performance including a low threshold current of 50 mA, a threshold current density of 1.3 kA/cm2 and operation at elevated temperature up to 59 °C in CW mode was achieved. Comparison of lasers grown on Si and native InP substrates in the same growth run was made. Based on the laser characteristics measured at room temperature and elevated temperatures, the QDash quality on the two substrates is comparable. These results suggest that MOCVD is a viable technique for lasers on Si growth and represent an advance towards silicon-based photonic-electronic integration and manufacturing.

20.
Opt Express ; 28(18): 26823-26835, 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32906949

RESUMO

Compared to quantum well (QW) lasers, lower dimensional quantum dot (QD) or quantum dash (QDash) devices demonstrate superior performances, owing to their quantized energy levels and increased carrier confinement. Here, we report the systematic comparison of static and dynamic properties of long wavelength (1550 nm) QDash and QW lasers. For the QDash lasers, a higher maximum operating temperature and lower temperature dependence was achieved for long cavities, although the threshold current densities were larger than the QW reference devices. The lasing characteristics for QDashes are significantly improved following the application of a high reflectance (HR) coating on the rear facets. The QDash lasers also exhibit three orders lower dark current, of 45 µA/cm2 under -1 V reverse bias. Small signal modulation on the 4 × 550 µm2 Fabry-Perot cavities yields a modulation efficiency of 0.48 GHz/√mA and a maximum 3-dB bandwidth of 7.4 GHz for QDashes, slightly larger than that for the QW devices. Meanwhile, a stronger damping effect was observed for the QDash lasers due to their lower differential gain.

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