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1.
Chin J Cancer Res ; 36(2): 124-137, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38751436

RESUMO

Objective: Primary resistance to trastuzumab frequently occurs in human epidermal growth factor receptor 2 (HER2)-positive (+) breast cancer patients and remains a clinical challenge. Pyrotinib is a novel tyrosine kinase inhibitor that has shown efficacy in the treatment of HER2+ breast cancer. However, the efficacy of pyrotinib in HER2+ breast cancer with primary trastuzumab resistance is unknown. Methods: HER2+ breast cancer cells sensitive or primarily resistant to trastuzumab were treated with trastuzumab, pyrotinib, or the combination. Cell proliferation, migration, invasion, and HER2 downstream signal pathways were analyzed. The effects of pyrotinib plus trastuzumab and pertuzumab plus trastuzumab were compared in breast cancer cells in vitro and a xenograft mouse model with primary resistance to trastuzumab. Results: Pyrotinib had a therapeutic effect on trastuzumab-sensitive HER2+ breast cancer cells by inhibiting phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) and rat sarcoma virus (RAS)/rapidly accelerated fibrosarcoma (RAF)/mitogen-activated protein kinase (MAPK)/extracellular-signal regulated kinase (ERK) pathways. In primary trastuzumab-resistant cells, pyrotinib inhibited cell growth, migration, invasion, and HER2 downstream pathways, whereas trastuzumab had no effects. The combination with trastuzumab did not show increased effects compared with pyrotinib alone. Compared with pertuzumab plus trastuzumab, pyrotinib plus trastuzumab was more effective in inhibiting cell proliferation and HER2 downstream pathways in breast cancer cells and tumor growth in a trastuzumab-resistant HER2+ breast cancer xenograft model. Conclusions: Pyrotinib-containing treatments exhibited anti-cancer effects in HER2+ breast cancer cells sensitive and with primary resistance to trastuzumab. Notably, pyrotinib plus trastuzumab was more effective than trastuzumab plus pertuzumab in inhibiting tumor growth and HER2 downstream pathways in HER2+ breast cancer with primary resistance to trastuzumab. These findings support clinical testing of the therapeutic efficacy of dual anti-HER2 treatment combining an intracellular small molecule with an extracellular antibody.

2.
Int J Cancer ; 150(4): 705-717, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34648659

RESUMO

Because of the high heterogeneity of breast cancer outcome, identification of novel prognostic biomarkers is critical to improve patient stratification and guide precise treatment. We examined the prognostic value of gamma-interferon-inducible lysosomal thiol reductase (GILT) expression in a training set of 416 breast cancer patients and a validation set of 210 patients, and performed functional studies to investigate the functions and underlying mechanisms of GILT on breast cancer prognosis. Our results indicated that high GILT expression in breast cancer cells was associated with improved disease-free survival (DFS; hazard ratio [HR] = 0.189, 95% confidence interval [CI]: 0.099-0.361) and breast cancer-specific survival (BCSS; HR = 0.187, 95% CI: 0.080-0.437) of breast cancer patients both in the training set and the external validation set (HR = 0.453, 95% CI: 0.235-0.873 for DFS, HR = 0.488, 95% CI: 0.245-0.970 for BCSS). In vitro and in vivo studies showed that GILT overexpression inhibited breast cancer cells proliferation, invasion, migration and tumor formation in nude mice and increased sensitivity of breast cancer cells to standard treatment. Proteomics analysis indicated that GILT inhibited reactive oxygen species (ROS) and autophagy activation in breast cancer cells, and GILT overexpression-mediated tumor growth was further enhanced in the presence of autophagy or ROS inhibitors. Our results demonstrate that GILT expression can be effectively used to predict the prognosis and guide treatment strategies of breast cancer patients.


Assuntos
Neoplasias da Mama/mortalidade , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Autofagia/fisiologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Humanos , Pessoa de Meia-Idade , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/análise , Prognóstico , Espécies Reativas de Oxigênio/metabolismo
3.
Chin J Cancer Res ; 32(3): 347-360, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32694899

RESUMO

OBJECTIVE: Obesity is closely associated with metastasis in breast cancer patients. Secreted frizzled-related protein 5 (SFRP5), one of the novel adipokines with anti-inflammatory properties, is associated with obesity. This study aims to study the role of SFRP5 in the crosstalk between obesity and breast cancer metastasis and identify the underlying mechanism. METHODS: 3T3-L1 pre-adipocytes were differentiated to mature adipocytes and a hypertrophic adipocyte model was induced with palmitic acid (PA). Cell motility was measured in MDA-MB-231 and MCF-7 breast cancer cells co-cultured with adipocytes conditioned medium (CM) with or without SFRP5 protein. Wnt and epithelial-mesenchymal transition (EMT) signal pathways were investigated by western blot. Circulating SFRP5 level in 218 breast cancer patients and the association with clinicopathologic characteristics of breast cancer were further determined. Online databases ENCORI and PREDICT Plus were used to exam the link between SFRP5 and prognosis. RESULTS: Reduced SFRP5 level was detected in the hypertrophic adipocyte model. Recombinant SFRP5 protein inhibited MDA-MB-231 and MCF-7 cells invasion and migration induced by PA-treated adipocyte CM, and SFRP5 inhibition by specific antibody reversed the effect of SFRP5. Furthermore, SFRP5 significantly inhibited Wnt and downstream EMT in breast cancer cells. Low circulating SFRP5 level correlated with body mass index (BMI), lymph node (LN) metastasis, TNM stage and high Ki67 expression in breast cancer patients. Increased SFRP5 level was associated with favorable predicted survival. Kaplan-Meier curves showed high SFRP5 level in tumor tissue was associated with better outcome of breast cancer patients. CONCLUSIONS: Our findings demonstrated SFRP5 is a vital adipokine that mediates the crosslink between obesity and the metastatic potential of breast cancer. Promotion of SFRP5 expression in the adipose microenvironment may represent a novel approach for preventing breast cancer metastasis.

4.
J Cell Biochem ; 120(7): 12039-12050, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30805963

RESUMO

BACKGROUND: Breast cancer (BC) risk, development, and prognosis were closely related to obesity, diabetes mellitus, and metabolic syndrome. Protein tyrosine phosphatase, non-receptor type 1 (PTPN1) located on chromosome 20q13, could negatively regulate insulin and leptin signaling. In this study, we determined the association of PTPN1 polymorphisms with BC risk. METHODS: We analyzed the distribution of 11 selected PTPN1 single nucleotide polymorphisms in Chinese female patients with BC (n = 953) and healthy controls (n = 963) based on a multicenter case-control study. The association of PTPN1 genotypes and haplotypes frequencies with BC risk were determined by logistic regression analysis. Analyses were further stratified by body mass index (BMI), waist-hip rate (WHR), diabetes mellitus history, and fasting plasma glucose level. The eQTL (expression Quantitative Trait Loci) analysis for PTPN1 was conducted by GTEx database. RESULTS: There were significant differences between BC cases and control groups in menopausal status, number of births, and BMI. Four single nucleotide polymorphisms (SNPs; rs3215684, rs3787345, rs718049, and rs718050) decreased overall BC risk, and other seven SNPs showed no significant association with BC risk. In multivariate analysis, BMI and rs3215684 DT + DD genotype were identified as independent risk factors for BC, and mutated genotypes of rs3215684 were correlated with increased PTPN1 expression. There are no haplotypes showed different frequencies between cases and controls. In the stratified analysis, rs2206656 showed a significant association with decreased BC risk in the subgroup of BMI ≤ 24 kg/m 2 , while rs3215684 and rs718049 showed lower BC risk in the subgroup of WHR > 0.85. Seven SNPs showed lower BC risk in the subgroup with diabetes mellitus history and/or fasting plasma glucose level ≥ 7 mM, while rs754118 decreased BC risk in the subgroup of fasting plasma glucose level < 7 mM. CONCLUSION: Our findings suggest that PTPN1 SNPs associated with BC susceptibility in Chinese females, which also suggested a novel mechanism between obesity, diabetes mellitus, and BC risk.

5.
Entropy (Basel) ; 20(12)2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33266634

RESUMO

The partitioning of the alloying elements into the γ″ nanoparticles in a Ni2CoFeCrNb0.15 high entropy alloy was studied by the combination of atom probe tomography and first-principles calculations. The atom probe tomography results show that the Co, Fe, and Cr atoms incorporated into the Ni3Nb-type γ″ nanoparticles but their partitioning behaviors are significantly different. The Co element is much easier to partition into the γ″ nanoparticles than Fe and Cr elements. The first-principles calculations demonstrated that the different partitioning behaviors of Co, Fe and Cr elements into the γ″ nanoparticles resulted from the differences of their specific chemical potentials and bonding states in the γ″ phase.

6.
J Virol ; 90(15): 6625-6641, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27170754

RESUMO

UNLABELLED: The lack of a peptide-swine leukocyte antigen class I (pSLA I) complex structure presents difficulties for the study of swine cytotoxic T lymphocyte (CTL) immunity and molecule vaccine development to eliminate important swine viral diseases, such as influenza A virus (IAV). Here, after cloning and comparing 28 SLA I allelic genes from Chinese Heishan pigs, pSLA-3*hs0202 was crystalized and solved. SLA-3*hs0202 binding with sß2m and a KMNTQFTAV (hemagglutinin [HA]-KMN9) peptide from the 2009 pandemic swine H1N1 strain clearly displayed two distinct conformations with HA-KMN9 peptides in the structures, which are believed to be beneficial to stimulate a broad spectrum of CTL immune responses. Notably, we found that different HA-KMN9 conformations are caused, not only by the flexibility of the side chains of residues in the peptide-binding groove (PBG), but also by the skewing of α1 and α2 helixes forming the PBG. In addition, alanine scanning and circular-dichroism (CD) spectra confirmed that the B, D, and F pockets play critical biochemical roles in determining the peptide-binding motif of SLA-3*hs0202. Based on biochemical parameters and comparisons to similar pockets in other known major histocompatibility complex class I (MHC-I) structures, the fundamental motif for SLA-3*hs0202 was determined to be X-(M/A/R)-(N/Q/R/F)-X-X-X-X-X-(V/I) by refolding in vitro and multiple mutant peptides. Finally, 28 SLA-3*hs0202-restricted epitope candidates were identified from important IAV strains, and two of them have been found in humans as HLA-A*0201-specific IAV epitopes. Structural and biochemical illumination of pSLA-3*hs0202 can benefit vaccine development to control IAV in swine. IMPORTANCE: We crystalized and solved the first SLA-3 structure, SLA-3*hs0202, and found that it could present the same IAV peptide with two distinct conformations. Unlike previous findings showing that variable peptide conformations are caused only by the flexibility of the side chains in the groove, the skewing of the α1 and α2 helixes is important in the different peptide conformations in SLA-3*hs0202. We also determined the fundamental motif for SLA-3*hs0202 to be X-(M/A/R)-(N/Q/R/F)-X-X-X-X-X-(V/I) based on a series of structural and biochemical analyses, and 28 SLA-3*hs0202-restricted epitope candidates were identified from important IAV strains. We believe our structure and analyses of pSLA-3*hs0202 can benefit vaccine development to control IAV in swine.


Assuntos
Epitopos de Linfócito T/imunologia , Antígenos de Histocompatibilidade Classe II/química , Antígenos de Histocompatibilidade Classe I/química , Vírus da Influenza A/imunologia , Fragmentos de Peptídeos/imunologia , Linfócitos T Citotóxicos/imunologia , Sequência de Aminoácidos , Animais , Apresentação de Antígeno , Dicroísmo Circular , Cristalografia por Raios X , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Modelos Moleculares , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/virologia , Ligação Proteica , Conformação Proteica , Estabilidade Proteica , Homologia de Sequência de Aminoácidos , Suínos
7.
J Clin Endocrinol Metab ; 109(6): 1474-1484, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38157274

RESUMO

CONTEXT: Cushing syndrome (CS) is a severe endocrine disease characterized by excessive secretion of cortisol with multiple metabolic disorders. While gut microbial dysbiosis plays a vital role in metabolic disorders, the role of gut microbiota in CS remains unclear. OBJECTIVE: The objective of this work is to examine the alteration of gut microbiota in patients with CS. METHODS: We performed shotgun metagenomic sequencing of fecal samples from 78 patients with CS and 78 healthy controls matched for age and body mass index. Furthermore, we verify the cortisol degradation capacity of Ruminococcus gnavus in vitro and identify the potential metabolite by LC-MC/MS. RESULTS: We observed significant differences in microbial composition between CS and controls in both sexes, with CS showing reduced Bacteroidetes (Bacteroides vulgatus) and elevated Firmicutes (Erysipelotrichaceae_bacterium_6_1_45) and Proteobacteria (Enterobacter cloacae). Despite distinct causes of hypercortisolism in ACTH-dependent and ACTH-independent CS, we found no significant differences in metabolic profiles or gut microbiota between the 2 subgroups. Furthermore, we identified a group of gut species, including R. gnavus, that were positively correlated with cortisol levels in CS. These bacteria were found to harbor cortisol-degrading desAB genes and were consistently enriched in CS. Moreover, we demonstrated the efficient capacity of R. gnavus to degrade cortisol to 11-oxygenated androgens in vitro. CONCLUSION: This study provides evidence of gut microbial dysbiosis in patients with CS and identifies a group of CS-enriched bacteria capable of degrading cortisol. These findings highlight the potential role of gut microbiota in regulating host steroid hormone levels, and consequently host health.


Assuntos
Síndrome de Cushing , Disbiose , Fezes , Microbioma Gastrointestinal , Hidrocortisona , Humanos , Disbiose/microbiologia , Disbiose/metabolismo , Masculino , Feminino , Microbioma Gastrointestinal/fisiologia , Síndrome de Cushing/microbiologia , Síndrome de Cushing/metabolismo , Hidrocortisona/metabolismo , Pessoa de Meia-Idade , Adulto , Fezes/microbiologia , Estudos de Casos e Controles , Clostridiales/isolamento & purificação , Clostridiales/metabolismo
8.
Genome Med ; 16(1): 11, 2024 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-38217005

RESUMO

BACKGROUND: Neoadjuvant chemotherapy (NAC) has become a standard treatment strategy for breast cancer (BC). However, owing to the high heterogeneity of these tumors, it is unclear which patient population most likely benefit from NAC. Multi-omics offer an improved approach to uncovering genomic and transcriptomic changes before and after NAC in BC and to identifying molecular features associated with NAC sensitivity. METHODS: We performed whole-exome and RNA sequencing on 233 samples (including matched pre- and post-treatment tumors) from 50 BC patients with rigorously defined responses to NAC and analyzed changes in the multi-omics landscape. Molecular features associated with NAC response were identified and validated in a larger internal, and two external validation cohorts, as well as in vitro experiments. RESULTS: The most frequently altered genes were TP53, TTN, and MUC16 in both pre- and post-treatment tumors. In comparison with pre-treatment tumors, there was a significant decrease in C > A transversion mutations in post-treatment tumors (P = 0.020). NAC significantly decreased the mutation rate (P = 0.006) of the DNA repair pathway and gene expression levels (FDR = 0.007) in this pathway. NAC also significantly changed the expression level of immune checkpoint genes and the abundance of tumor-infiltrating immune and stroma cells, including B cells, activated dendritic cells, γδT cells, M2 macrophages and endothelial cells. Furthermore, there was a higher rate of C > T substitutions in NAC nonresponsive tumors than responsive ones, especially when the substitution site was flanked by C and G. Importantly, there was a unique amplified region at 8p11.23 (containing ADGRA2 and ADRB3) and a deleted region at 3p13 (harboring FOXP1) in NAC nonresponsive and responsive tumors, respectively. Particularly, the CDKAL1 missense variant P409L (p.Pro409Leu, c.1226C > T) decreased BC cell sensitivity to docetaxel, and ADGRA2 or ADRB3 gene amplifications were associated with worse NAC response and poor prognosis in BC patients. CONCLUSIONS: Our study has revealed genomic and transcriptomic landscape changes following NAC in BC, and identified novel biomarkers (CDKAL1P409L, ADGRA2 and ADRB3) underlying chemotherapy resistance and poor prognosis, which could guide the development of personalized treatments for BC.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Terapia Neoadjuvante , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Perfilação da Expressão Gênica , Genômica , Proteínas Repressoras/genética , Fatores de Transcrição Forkhead/genética , Receptores Adrenérgicos beta 3/genética
9.
Aquat Toxicol ; 256: 106422, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36773443

RESUMO

The environmental occurrence of nanoplastics (NPs) is now evident but their long-term impacts on organisms are unclear, limiting ecological and health risk assessment. We hypothesized that chronic exposure to low particle concentrations of NPs can result in gut-associated toxicity, and subsequently affect survival of fish. Japanese medaka Oryzias latipes were exposed to polystyrene NPs (diameter 100 nm; 0, 10, 104, and 106 items/L) for 3 months, and histopathology, digestive and antioxidant enzymes, immunity, intestinal permeability, gut microbiota, and mortality were assessed. NP exposures caused intestinal lesions, and increased intestinal permeability of the gut. The trypsin, lipase, and chymotrypsin activities were increased, but the amylase activity was decreased. Oxidative damage was reflected by the decreased superoxide dismutase and alkaline phosphatase and increased malondialdehyde, catalase, and lysozyme. The integrated biomarkers response index values of all NP-exposed medaka were significantly increased compared to the control group. Moreover, NP exposures resulted in a decrease of diversity and changed the intestinal microbiota composition. Our results provide new evidence that long-term NPs exposure impaired the health of fish at extremely low particle concentrations, suggesting the need for long-term toxicological studies resembling environmental particle concentrations when assessing the risk of NPs.


Assuntos
Oryzias , Poluentes Químicos da Água , Animais , Oryzias/fisiologia , Microplásticos/toxicidade , Poluentes Químicos da Água/toxicidade , Antioxidantes/metabolismo , Estresse Oxidativo
10.
J Clin Endocrinol Metab ; 107(8): e3304-e3312, 2022 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-35512387

RESUMO

CONTEXT: Measurement of plasma steroids is necessary for diagnosis of congenital adrenal hyperplasia (CAH). We sought to establish an efficient strategy for detection and subtyping of CAH with a machine-learning algorithm. METHODS: Clinical phenotype and genetic testing were used to provide CAH diagnosis and subtype. We profiled 13 major steroid hormones by liquid chromatography-tandem mass spectrometry. A multiclassifier system was established to distinguish 11ß-hydroxylase deficiency (11ßOHD), 17α-hydroxylase/17,20-lyase deficiency (17OHD), and 21α-hydroxylase deficiency (21OHD) in a discovery cohort (n = 226). It was then validated in an independent cohort (n = 111) and finally applied in a perspective cohort of 256 patients. The diagnostic performance on the basis of area under receiver operating characteristic curves (AUCs) was evaluated. RESULTS: A cascade logistic regression model, we named the "Steroidogenesis Score", was able to discriminate the 3 most common CAH subtypes: 11ßOHD, 17OHD, and 21OHD. In the perspective application cohort, the steroidogenesis score had a high diagnostic accuracy for all 3 subtypes, 11ßOHD (AUC, 0.994; 95% CI, 0.983-1.000), 17OHD (AUC, 0.993; 95% CI, 0.985-1.000), and 21OHD (AUC, 0.979; 95% CI, 0.964-0.994). For nonclassic 21OHD patients, the tool presented with significantly higher sensitivity compared with measurement of basal 17α-hydroxyprogesterone (17OHP) (0.973 vs 0.840, P = 0.005) and was not inferior to measurement of basal vs stimulated 17OHP (0.973 vs 0.947, P = 0.681). CONCLUSIONS: The steroidogenesis score was biochemically interpretable and showed high accuracy in identifying CAH patients, especially for nonclassic 21OHD patients, thus offering a standardized approach to diagnose and subtype CAH.


Assuntos
Hiperplasia Suprarrenal Congênita , 17-alfa-Hidroxiprogesterona/sangue , Hiperplasia Suprarrenal Congênita/sangue , Hiperplasia Suprarrenal Congênita/classificação , Cromatografia Líquida , Hormônios Esteroides Gonadais/sangue , Humanos
11.
Front Endocrinol (Lausanne) ; 13: 907019, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35784571

RESUMO

Background & Aims: Primary hyperparathyroidism(PHPT) has been evolving into a milder asymptomatic disease. No study has assessed the association between famine exposure and such a shift. We aim to explore the effects of China's Great Famine exposure on the changing pattern of PHPT phenotypes. Methods: 750 PHPT patients diagnosed from 2000 to 2019 were studied. The clinical presentations were compared between them in recent 10 years (2010-2019) and previous 10 years (2000-2009). Participants were then categorized into fetal, childhood, adolescent, adult exposure, and unexposed groups. Logistic regression was used to estimate the odds ratios (ORs) and confidence intervals (CIs) of famine exposure as factors contributing to the changes in the clinical presentations of PHPT. Results: Serum levels of PTH, albumin-corrected Ca, tumor size, eGFR, BMDs (all P<0.001), and clinical symptoms became milder in recent 10 years. Famine exposure (72.6% vs 58.4%, P<0.001), especially the adult exposure (18.8% vs 4.1%, P<0.001)was significant less in recent 10 years. The ORs (95%CIs) of having upper 3rd tertile PTH were 2.79(1.34,5.8), 2.07(1.04,4.11), 3.10(1.15,8.38) and 8.85(2.56,30.56) for patients with fetal, childhood, adolescent and adult famine exposure, respectively. The ORs (95%CIs) of upper 3rd tertile albumin-corrected Ca and upper 3rd tertile of tumor size was 4.78(1.39, 16.38) and 4.07(1.12,14.84) for participants with adult famine exposure, respectively. All these associations were independent of age, sex, disease duration and other confounders. Conclusions: The clinical manifestations of PHPT in China continue to be milder. Exposure to famine is associated with PHPT. Less famine exposure might be responsible for the mile form of PHPT in recent years.


Assuntos
Hiperparatireoidismo Primário , Neoplasias , Efeitos Tardios da Exposição Pré-Natal , Inanição , Adolescente , Adulto , Albuminas , Criança , Fome Epidêmica , Feminino , Feto , Humanos , Hiperparatireoidismo Primário/complicações , Hiperparatireoidismo Primário/epidemiologia , Masculino , Neoplasias/complicações , Fenótipo , Gravidez , Inanição/complicações
12.
Rev Sci Instrum ; 93(11): 115113, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36461463

RESUMO

The China Spallation Neutron Source drift tube linac (DTL) is a high current intensity linear accelerator operated in pulsed mode. Beam loss is the most important cause of DTL performance degradation. Therefore, control of beam loss is very crucial to the linac's commission and routine operation. The beam loss in beam pulse width (∼several hundreds of microseconds) can be regarded as an instantaneous process, which may cause the local temperature of the drift tubes (DTs) to exceed the melting point or the thermal stress to exceed the material yield strength, resulting in permanent damage to the DTs. RF heating and beam loss are two major heat sources of the DTs during operation. First, temperature rise due to RF power dissipation is evaluated in this paper. Then, the thermomechanical response due to beam loss at different energies is investigated. It is found that the 3-MeV beam loss has the greatest stopping power and causes the largest temperature rise to the DTs. The maximum beam current loss for different working conditions is analyzed by both analytical method and ANSYS simulations, and the details will also be discussed in this paper.

13.
Front Oncol ; 12: 809570, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35223490

RESUMO

BACKGROUND: Leptin (LEP) plays a physiological role through its specific receptor (LEPR) and is involved in the occurrence and development of breast cancer. Our current study aimed at determining the influence of single-nucleotide polymorphisms (SNPs) in the genes coding for LEP and LEPR on breast cancer risk. METHODS: In the present study, 963 breast cancer cases and 953 controls were enrolled. Five SNPs of LEP and two of LEPR were chosen to evaluate the correlation of selected SNPs with breast cancer susceptibility among women in northern and eastern China. Analyses were further stratified by body mass index (BMI), waist-hip rate (WHR), estrogen receptor, and progesterone receptor status. The expression patterns of risk variant-associated genes were detected by expression quantitative trait locus (eQTL) analysis with eQTLGen and The Cancer Genome Atlas database. RESULTS: There were significant differences between breast cancer cases and control groups in the menopausal status and family history of breast cancer. Two SNPs (rs1137101 and rs4655555) of the LEPR gene decreased overall breast cancer risk, and other five SNPs showed no significant association with breast cancer risk. rs1137101 (GA vs. GG; adjusted OR = 0.719, 95% CI = 0.578-0.894, p = 0.003) and rs4655555 (TT vs. AA; adjusted OR = 0.574, 95% CI = 0.377-0.873, p = 0.009) significantly decreased breast cancer risk after Bonferroni correction for multiple testing. In subgroup analyses, the GA and GA + AA genotypes of LEPR rs1137101 associated with decreased breast cancer risk in the subgroup of BMI ≤ 24 kg/m2 or WHR ≥ 0.85 after Bonferroni correction. Furthermore, we found that the expressions of rs4655555-associated gene LEPR and leptin receptor overlapping transcript (LEPROT) were upregulated in breast cancer tumor tissues compared with adjacent normal tissues, and a higher expression of LEPR in tumor tissues was correlated with poor prognosis of breast cancer patients using The Cancer Genome Atlas Breast Invasive Carcinoma (TCGA-BRCA) data. CONCLUSION: Our study demonstrated that the polymorphisms rs1137101 and rs4655555 located in the LEPR gene decreased breast cancer risk in Chinese females, which might be a research-worthy bio-diagnostic marker and applied for early prediction and risk assessment of breast cancer.

14.
Part Fibre Toxicol ; 8: 33, 2011 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-22098626

RESUMO

BACKGROUND: Our previous studies demonstrated that tilmicosin-loaded hydrogenated castor oil solid lipid nanoparticles (Til-HCO-SLN) are a promising formulation for enhanced pharmacological activity and therapeutic efficacy in veterinary use. The purpose of this work was to evaluate the acute toxicity of Til-HCO-SLN. METHODS: Two nanoparticle doses were used for the study in ICR mice. The low dose (766 mg/kg.bw) with tilmicosin 7.5 times of the clinic dosage and below the median lethal dose (LD(50)) was subcutaneously administered twice on the first and 7th day. The single high dose (5 g/kg.bw) was the practical upper limit in an acute toxicity study and was administered subcutaneously on the first day. Blank HCO-SLN, native tilmicosin, and saline solution were included as controls. After medication, animals were monitored over 14 days, and then necropsied. Signs of toxicity were evaluated via mortality, symptoms of treatment effect, gross and microscopic pathology, and hematologic and biochemical parameters. RESULTS: After administration of native tilmicosin, all mice died within 2 h in the high dose group, in the low dose group 3 died after the first and 2 died after the second injections. The surviving mice in the tilmicosin low dose group showed hypoactivity, accelerated breath, gloomy spirit and lethargy. In contrast, all mice in Til-HCO-SLN and blank HCO-SLN groups survived at both low and high doses. The high nanoparticle dose induced transient clinical symptoms of treatment effect such as transient reversible action retardation, anorexy and gloomy spirit, increased spleen and liver coefficients and decreased heart coefficients, microscopic pathological changes of liver, spleen and heart, and minor changes in hematologic and biochemical parameters, but no adverse effects were observed in the nanoparticle low dose group. CONCLUSIONS: The results revealed that the LD50 of Til-HCO-SLN and blank HCO-SLN exceeded 5 g/kg.bw and thus the nanoparticles are considered low toxic according to the toxicity categories of chemicals. Moreover, HCO-SLN significantly decreased the toxicity of tilmicosin. Normal clinic dosage of Til-HCO-SLN is safe as evaluated by acute toxicity.


Assuntos
Antibacterianos/toxicidade , Óleo de Rícino/toxicidade , Tilosina/análogos & derivados , Animais , Peso Corporal/efeitos dos fármacos , Óleo de Rícino/química , Ingestão de Líquidos/efeitos dos fármacos , Portadores de Fármacos/química , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Coração/efeitos dos fármacos , Hidrogenação , Dose Letal Mediana , Lipídeos/química , Fígado/efeitos dos fármacos , Fígado/patologia , Longevidade/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Miocárdio/patologia , Nanopartículas/química , Nanopartículas/toxicidade , Tamanho da Partícula , Baço/efeitos dos fármacos , Baço/patologia , Testes de Toxicidade Aguda , Tilosina/toxicidade
15.
Med Phys ; 48(2): 627-639, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33111361

RESUMO

PURPOSE: Recent studies have witnessed that self-attention modules can better solve the vision understanding problems by capturing long-range dependencies. However, there are very few works designing a lightweight self-attention module to improve the quality of MRI reconstruction. Furthermore, it can be observed that several important self-attention modules (e.g., the non-local block) cause high computational complexity and need a huge number of GPU memory when the size of the input feature is large. The purpose of this study is to design a lightweight yet effective spatial orthogonal attention module (SOAM) to capture long-range dependencies, and develop a novel spatial orthogonal attention generative adversarial network, termed as SOGAN, to achieve more accurate MRI reconstruction. METHODS: We first develop a lightweight SOAM, which can generate two small attention maps to effectively aggregate the long-range contextual information in vertical and horizontal directions, respectively. Then, we embed the proposed SOAMs into the concatenated convolutional autoencoders to form the generator of the proposed SOGAN. RESULTS: The experimental results demonstrate that the proposed SOAMs improve the quality of the reconstructed MR images effectively by capturing long-range dependencies. Besides, compared with state-of-the-art deep learning-based CS-MRI methods, the proposed SOGAN reconstructs MR images more accurately, but with fewer model parameters. CONCLUSIONS: The proposed SOAM is a lightweight yet effective self-attention module to capture long-range dependencies, thus, can improve the quality of MRI reconstruction to a large extent. Besides, with the help of SOAMs, the proposed SOGAN outperforms the state-of-the-art deep learning-based CS-MRI methods.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Atenção
16.
J Steroid Biochem Mol Biol ; 206: 105806, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33340681

RESUMO

Polycystic ovary syndrome (PCOS) is a heterogeneous disease defined by the presence of at least two of the following features: hyperandrogenism, oligoanovulation (OA), and polycystic ovarian morphology (PCOM). Hyperandrogenism is considered the cornerstone of PCOS. However, the most prevalent phenotype in Chinese women with PCOS is OA + PCOM [normo-androgenic PCOS (NA-PCOS)]. It has been reported that PCOS women have higher androgen levels in follicular fluid (FF), but whether NA-PCOS women have the same intrafollicular steroid profiles as hyperandrogenic PCOS (HA-PCOS) women has not been explored. In this study, we analyzed 17 steroids in stimulated size-matched ovarian follicles (16-18 mm) from 166 controls and 141 PCOS women [87 NA-PCOS and 54 HA-PCOS women, defined by a single serum testosterone (T) immunoassay measurement] using liquid chromatography tandem mass spectrometry, and investigated their relationship with baseline characteristics. No significant differences in intrafollicular steroid levels and product/precursor ratios between NA-PCOS and HA-PCOS women were observed, though HA-PCOS women had significantly higher serum luteinizing hormone and T levels than NA-PCOS women. NA-PCOS and HA-PCOS women had significantly higher levels of androstenedione (AD), T and free androgen index, higher enzyme activity of P450c17 (AD/17OH-progesterone), 3ßHSD2 (17OH-progesterone /17OH-pregnenolone) and P450c11 (corticosterone /11-deoxycorticosterone), lower levels of pregnenolone, 17OH-pregnenolone and 11-deoxycorticosterone, and decreased enzyme activity of P450aro (estrone/AD and estradiol/T) and 5α-reductase (dihydrotestosterone/T) in FF than controls. NA-PCOS women had significantly higher intrafollicular cortisol levels and lower 11ßHSD2 (cortisone/cortisol) activity than controls. Baseline serum T levels were slightly correlated with intrafollicular estrogens (E1: r = 0.192, p = 0.019; E2: r = 0.248, p = 0.002; E3: r = 0.248, p = 0.002) and androgens (DHEAS: r = 0.276, p = 0.001; AD: r = 0.185, p = 0.032; T: r = 0.173, p = 0.044) in controls and PCOS women respectively. Serum anti-Müllerian hormone (AMH) levels and antral follicle count (AFC) were correlated with intrafollicular cortisol (AMH: r = 0.380, p = 0.000; AFC: r = 0.177, p = 0.036) and corticosterone (AMH: r = 0.212, p = 0.048; AFC: r = 0.219, p = 0.009) levels in PCOS women. In conclusion, NA-PCOS and HA-PCOS women had statistically similar steroid metabolome profiles in FF, both of which showed a generally decreased steroidogenesis and hyperandrogenism compared to controls.


Assuntos
Hiperandrogenismo/sangue , Metaboloma/genética , Síndrome do Ovário Policístico/sangue , Esteroides/sangue , Adulto , Androgênios/sangue , Androstenodiona/sangue , Hormônio Antimülleriano , Estradiol/sangue , Estrogênios/sangue , Feminino , Líquido Folicular/metabolismo , Humanos , Hidrocortisona/sangue , Hiperandrogenismo/genética , Hiperandrogenismo/metabolismo , Hiperandrogenismo/patologia , Hormônio Luteinizante/sangue , Folículo Ovariano/metabolismo , Folículo Ovariano/patologia , Síndrome do Ovário Policístico/genética , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/patologia , Esteroides/metabolismo , Testosterona/sangue , Adulto Jovem
17.
Endocrine ; 74(2): 340-348, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34028648

RESUMO

PURPOSE: Widespread use of sensitive ultrasound examination led to an increasing detection of medullary thyroid microcarcinoma (micro-MTC). This prospective study evaluated the diagnostic accuracy of Fine-needle Aspiration Biopsy Cytology (FNAB-C) and calcitonin assay in Fine-needle Aspiration Biopsy wash-out fluid (FNAB-CT) in thyroid nodules less than 1 cm with elevated serum calcitonin(sCT). METHODS: 87 thyroid nodules from 60 patients with elevated sCT (>10 pg/ml) were included and 51 were thyroid nodules less than 1cm. FNAB-CT and FNAB-C were performed to distinguish medullary thyroid carcinoma (MTC) lesions before surgery, histopathologic diagnoses served as main reference standards. RESULTS: FNAB-CT had a greater performance over FNAB-C for preoperative diagnosis of MTC (diagnostic accuracy: 98.85 vs 61.90%, sensitivity: 98.55 vs 55.07%, specificity: 100 vs 97.44%), especially for micro-MTC: FNAB-C established a sensitivity and diagnostic accuracy of 48.78 and 58% respectively, while FNAB-CT reached 97.56% sensitivity and 98.04% diagnostic accuracy. CONCLUSIONS: FNAB-CT demonstrated high diagnostic accuracy in diagnosing micro-MTC. Patients with microscopic thyroid nodules and elevated sCT level should perform FNAB-CT to exclude the diagnosis of MTC lesions.


Assuntos
Neoplasias da Glândula Tireoide , Nódulo da Glândula Tireoide , Biópsia por Agulha Fina , Calcitonina , Humanos , Estudos Prospectivos , Sensibilidade e Especificidade , Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/diagnóstico por imagem , Tomografia Computadorizada por Raios X
18.
Cancer Med ; 10(8): 2752-2762, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33734613

RESUMO

BACKGROUND: X-ray repair cross-complementary 5 (XRCC5) and 6 (XRCC6) are critical for DNA repair. Few studies have assessed their association with breast cancer risk, and related gene-environment interactions remain poorly understood. This study aimed to determine the influence of XRCC5/6 polymorphisms on breast cancer risk, and their interactions with cigarette smoking, alcohol consumption, and sleep satisfaction. METHODS: The study included 1039 patients with breast cancer and 1040 controls. Four single-nucleotide polymorphisms of XRCC5 and two of XRCC6 were genotyped. Information about smoking, alcohol consumption, and sleep satisfaction was collected through questionnaires. Odds ratios (OR) and related 95% confidence intervals (95% CI) were assessed using unconditional logistic regression models. Gene-environment interactions were analyzed using logistic regression with multiplicative interaction models. RESULTS: XRCC5 rs16855458 was associated with increased breast cancer risk in the co-dominant (ptrend  = 0.003) and dominant (CA + AA vs. CC, OR = 1.29, 95% CI = 1.07-1.56, p = 0.008) genetic models after Bonferroni correction. The CG + GG genotype of XRCC6 rs2267437 was associated with an increased risk of estrogen receptor-negative/progesterone receptor-negative (ER-/PR-) breast cancer (CG + GG vs. CC: OR = 1.54, 95% CI = 1.12-2.13, p = 0.008) after Bonferroni correction. Moreover, an antagonistic interaction between XRCC5 rs16855458 and alcohol consumption (pinteraction  = 0.017), and a synergistic interaction between XRCC6 rs2267437 and sleep satisfaction were associated with breast cancer risk (pinteraction  = 0.0497). However, these interactions became insignificant after Bonferroni correction. CONCLUSION: XRCC5 rs16855458 was associated with breast cancer risk, and XRCC6 rs2267437 was associated with the risk of ER-/PR- breast cancer. Breast cancer risk associated with XRCC5 and XRCC6 polymorphisms might vary according to alcohol consumption and sleep satisfaction, respectively, and merit further investigation.


Assuntos
Consumo de Bebidas Alcoólicas/genética , Neoplasias da Mama/genética , Autoantígeno Ku/genética , Fumar/genética , Adulto , Idoso , Povo Asiático/genética , Neoplasias da Mama/metabolismo , Estudos de Casos e Controles , Feminino , Frequência do Gene , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Satisfação Pessoal , Polimorfismo de Nucleotídeo Único , Sono/fisiologia
19.
Endocrine ; 69(1): 196-203, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32291738

RESUMO

PURPOSE: Thyroid dysfunction has been reported in hypercortisolism. Previous findings regarding changes in thyroid function due to cortisol-producing adenoma (CPA) have been inconsistent. The study aimed to investigate the association between thyroid function and excessive cortisol secretion in patients with CPA and to explore the changes in pituitary function after adrenalectomy. METHODS: We conducted a retrospective study; thyroid function was evaluated in 94 patients with CPA and 94 healthy controls (HC) matched for age and sex. A total of 94 patients with nonfunctioning adrenal incidentalomas (NFAIs) were recruited as a second control group. RESULTS: Serum thyroid stimulating hormone (TSH) and free thyroxine (T4) levels were significantly lower in the CPA group than in the HC and NFAIs groups (P < 0.001). The prevalence of central hypothyroidism was 12.8% in the CPA group and increased according to serum cortisol quartiles (P for trend = 0.025). According to the stepwise multiple linear regression analysis, serum cortisol was negatively associated with TSH and free T4 levels in the CPA group after adjustment for body mass index and age. Furthermore, decreased TSH levels were corrected by adrenalectomy [0.75 (0.50, 1.14) vs. 1.91 (1.36, 2.71) µIU/ml, P < 0.001], in parallel with a recovery in free T4 levels [11.20 (10.00, 12.43) vs. 12.04 (11.24, 13.01), P < 0.001]. Postoperative growth hormone and prolactin levels did not change compared with baseline. CONCLUSION: Serum TSH and free T4 levels were decreased in patients with CPA, and dysfunction of the hypothalamic-pituitary-thyroid axis might be reversible after surgery.


Assuntos
Adenoma , Neoplasias das Glândulas Suprarrenais , Adenoma/cirurgia , Humanos , Hidrocortisona , Estudos Retrospectivos , Glândula Tireoide/cirurgia , Tireotropina
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