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1.
Anal Chem ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39250656

RESUMO

PIWI-interacting RNAs (piRNAs) are a type of endogenous noncoding RNAs with a length of 24-31 nucleotides, and they can specifically bind with PIWI proteins to form the piRNA/PIWI complexes for regulating multiple physiological and pathological processes. Herein, we develop a bidirectional polymerization-transcription amplification-encoded dual-color fluorescent biosensor for label-free and primer-free measurements of multiple piRNAs. The designed hairpin probe contains a palindromic tail, and it can serve as the target recognition unit, polymerization primer, and transcription template. In the presence of target piRNAs, the hairpin probes are opened to expose a palindromic sequence that can trigger bidirectional polymerization and transcription reaction with the assistance of KF polymerase and T7 RNA polymerase for the production of numerous RNA aptamers. The aptamers subsequently bind with the corresponding fluorophores (DFHBI-1T/MG) to form the RNA aptamer-fluorophore complexes for the generation of enhanced fluorescence signals. This biosensor can sensitively detect piR-36026 with a limit of detection (LOD) of 82.08 aM and piR-36743 with a LOD of 44.44 aM. Moreover, it can quantify cellular piRNAs with single-cell sensitivity and distinguish cancer cells from normal cells. Furthermore, it has the capability of distinguishing the expression of piRNAs in the tissues of breast cancer patients and healthy individuals. By simply altering the target recognition site of the hairpin probe, this biosensor can be extended to detect various piRNAs, offering a powerful platform for piRNA-related clinical diagnostics and therapeutics.

2.
Quant Imaging Med Surg ; 14(3): 2415-2425, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38545043

RESUMO

Background: The long-term survival of kidney transplants is often influenced by various factors, among which renal allograft rejection is the most notable factor. A noninvasive and reliable imaging biomarker correlating with kidney function and histopathology would facilitate longitudinal long-term follow-up of renal allografts. The aim of the study is to investigate the value of arterial spin labeling (ASL) combined with T1 mapping for assessing kidney function in patients with long-term renal transplant survival, and to establish radiological and histopathologic correlations between the magnetic resonance imaging (MRI) measurements and kidney allograft biopsy findings. Methods: Kidney transplant recipients who were admitted to the Department of Urology in First Affiliated Hospital of Soochow University between January and December 2022 were prospectively consecutively recruited [group A, estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m2; group B, 30≤ eGFR <60 mL/min/1.73 m2; group C, eGFR <30 mL/min/1.73 m2], and part of them underwent biopsies. All patients underwent ASL and T1 mapping. MRI parameters were calculated and analyzed. Results: A total of 63 patients (Group A, 30 cases; Group B, 20 cases; and Group C, 13 cases) were included in this cross-sectional study. Cortical T1 increased, whereas renal blood flow (RBF) and ΔT1 [100% × (cortical T1 - medullary T1)/cortical T1] decreased with the decrease of eGFR. The RBF, cortical T1, and ΔT1 values were moderately correlated with eGFR (r=0.569, -0.573, and 0.672, respectively). The MRI parameters were moderately correlated with Banff scores, which determined renal allograft rejection and chronicity. The area under the curve (AUC) for the discrimination of groups A versus B and groups A versus C were 0.740 [95% confidence interval (CI): 0.597-0.854, P=0.004] and 0.923 (95% CI: 0.800-0.982, P<0.001), respectively, using ASL; 0.873 (95% CI: 0.749-0.950, P<0.001) and 0.926 (95% CI: 0.803-0.983, P<0.001), respectively, using T1 mapping; and 0.892 (95% CI: 0.771-0.962, P<0.001) and 0.956 (95% CI: 0.846-0.995, P<0.001), respectively, using multi-parameter MRI. The AUC for discrimination between groups B and C was 0.729 (95% CI: 0.546-0.868, P=0.02) using ASL. Conclusions: The RBF, cortical T1, and ΔT1 can serve as new imaging biomarkers of kidney function and histopathological microstructure.

3.
J Magn Reson Imaging ; 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38059522

RESUMO

BACKGROUND: Previous studies using emerging diffusion MRI techniques have revealed damage to the white matter (WM) microstructure in amyotrophic lateral sclerosis (ALS), particularly the influence of crossed fibers, but there is a lack of subgroup analyses. PURPOSE: To detect WM microstructural changes in ALS patients using fixel-based analysis (FBA) and neurite orientation dispersion and density imaging (NODDI) MRI. STUDY TYPE: Prospective. POPULATION: Thirty-six ALS patients (aged 60.50 ± 9.5 years) and 25 healthy controls (HCs) (aged 58.90 ± 8.1 years). FIELD STRENGTH/SEQUENCE: 3 T; NODDI and FBA (b-values = 0, 1000, and 2500 seconds/mm2 ). ASSESSMENT: Subgroups were performed according to progression rate and cognition, including fast and slow progression (FP/SP), ALS with and without cognitive impairment (ALS-ci/ALS-nci). Fiber density (FD), fiber-bundle cross-section (FC), combined fiber density and cross-section (FDC), neurite density index (NDI), orientation dispersion index (ODI), isotropic volume fraction (ISO), and fractional anisotropy (FA) were calculated and their correlation with clinical variables examined. STATISTICAL TESTING: Chi-square test, Mann-Whitney U test, two-sample t test, partial correlation analysis, and false discovery rate (FDR) corrected. A P-value <0.05 was considered significant. RESULTS: ALS patients had lower FD and FDC values predominantly in the corticospinal tract (CST) and corpus callosum (CC) regions, as well as lower NDI value in the CC, radial crown, and internal capsule compared to HCs. Subgroup analysis based on progression rate and cognitive function showed significant differences in FBA results. The FC in the right CST region was significantly lower in the FP than SP, and the FD in the CC region was significantly lower in the ALS-ci than ALS-nci. Furthermore, a negative correlation was found between the mean FC value and the rate of progression in ALS patients (r = -0.408). DATA CONCLUSION: FBA is a powerful tool for detecting complex cerebral WM microstructural damage for evaluating ALS cognition and disease progression.

4.
J Fluoresc ; 33(4): 1577-1591, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36790630

RESUMO

A novel conjugated polymer PCZBTA-TBZ containing thiabendazole as recognition unit was synthesized via Suzuki coupling reaction, and its structural characterization, spectroscopic analysis and photophysical properties were investigated. In the metal ion response study, the addition of Cu2+ led to the occurrence of the photoinduced electron transfer (PET) mechanism, which significantly quenched the fluorescence of the polymer PCZBTA-TBZ with a quenching effect of 98%. Furthermore, I- can significantly quench the fluorescence of the polymer, but other anions have no such effect. According to the density functional theory calculation, compared with other polycarbazoles or other alternative copolymers containing carbazole, with alternating carbazole and triazole enhances the electron mobility and reduces the energy band gap of the polymer. Due to the strong coordination ability between Cu2+ and Cys, the adding Cys competes the Cu2+ in the [PCZBTA-TBZ-Cu2+] complex, blocking the occurrence of PET, and the fluorescence intensity of PCZBTA-TBZ is restored. The addition of other amino acids caused almost no change. The polymer is expected to be used for dual fluorescence detection of specific metal ions and Cys.

5.
Exp Physiol ; 107(12): 1493-1506, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36056793

RESUMO

NEW FINDINGS: What is the central question of this study? Activation of the glycogen synthase kinase 3 ß (GSK-3ß)-hypoxia-inducible factor 1 α (HIF-1α) pathway results in stimulation of pyroptosis under high glucose, and exerts actions in a number renal diseases: does this pathway have a role in renal tubular epithelial cells? What is the main finding and its importance? Down-regulation of GSK-3ß can inhibit pyroptosis of renal tubular epithelial cells induced by high glucose and this may be related to down-regulation of HIF-1α. This role of the GSK-3ß-HIF-1α pathway has not previously been reported and identifies a potential new therapeutic target in diabetic nephropathy. ABSTRACT: Diabetic nephropathy (DN) is not only one of the main complications of diabetes, but also has a high incidence rate and a high mortality rate. Glycogen synthase kinase 3 ß (GSK-3ß) and hypoxia-inducible factor 1 α (HIF-1α) have been demonstrated to influence DN by regulating pyroptosis. This study aimed to investigate the effect of the GSK-3ß-HIF-1α pathway on pyroptosis of high-glucose (HG)-induced renal tubular cells. Mouse renal proximal tubular epithelial cells (TKPT cells) were induced by HG to simulate DN cell and we transfected TKPT cells with GSK-3ß knockdown lentivirus. Western blot analysis confirmed the transfection effects and detected the expression of GSK-3ß, HIF-1α, Nod-like receptor protein 3 (NLRP3), cleaved-caspase-1, pro-caspase-1, gasdermin D (GSDMD) and GSDMD-N. The expression of GSDMD-N and HIF-1α were also verified by immunofluorescence. The levels of interleukin (IL)-1ß and IL-18 were measured by enzyme linked immunosorbent assay. Flow cytometric analysis determined the apoptosis rate. Results showed that HIF-1α expression was increased in HG-induced TKPT cells, and GSK-3ß knockdown could decrease the levels of NLRP3, cleaved-caspase-1, GSDMD-N and HIF-1α, verified by immunofluorescence. Moreover, GSK-3ß knockdown suppressed the expression of IL-1ß and IL-18, and reduced the apoptosis rate. Lithium chloride (LiCl) interference could cause the same changes as GSK-3ß knockdown for HG-induced TKPT cells, and dimethyloxallyl glycine could reverse the effect of GSK-3ß-knockdown interference. Our studies definitively demonstrate that the GSK-3ß-HIF-1α signalling pathway mediates HG-stimulated pyroptosis in renal tubular epithelial cells and that down-regulation of GSK-3ß inhibited HG-induced pyroptosis by inhibiting the expression of HIF-1α. These findings suggest a new potential target for the treatment of DN.


Assuntos
Nefropatias Diabéticas , Piroptose , Animais , Camundongos , Caspases/metabolismo , Nefropatias Diabéticas/tratamento farmacológico , Células Epiteliais/metabolismo , Glucose/efeitos adversos , Glicogênio Sintase Quinase 3 beta/metabolismo , Hipóxia , Interleucina-18 , Proteína 3 que Contém Domínio de Pirina da Família NLR , Proteínas NLR , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo
6.
Pathol Res Pract ; 216(7): 153001, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32534709

RESUMO

Gastric cancer (GC) remains one of the most lethal human malignancies, and exploring novel therapeutic targets for the treatment has been a major focus. The molecular mechanism of invasion and migration of GC cells remains unclear. The present study aimed to investigate the role of Tensin 4 and the associated molecular signaling pathways in the process of invasion and metastasis of GC. The expression of Tensin 4 protein and phosphorylated AKT (p-AKT) were evaluated in GC and normal adjacent tissues of 80 patients using immunohistochemistry staining. The expression of Tensin4 mRNA was analyzed in 10 GC tissues and 3 GC cell lines (SGC7901, MKN45, and MKN28) by qPCR. Cell proliferation, migration, and invasion were assessed using CCK-8 and Transwell assays in the Tensin 4 siRNA transfected SGC7901 cells and Tensin 4 plasmid transfected MKN28 cells. Additionally, protein expressions of Tensin 4, E-cadherin, vimentin, AKT, p-AKT, GSK-3ß, p-GSK-3ß, and Snail were analyzed by western blotting. The results demonstrated that the expression of Tensin 4 was significantly up-regulated in the GC tissues and cell lines, especially in the SGC7901 cells. The expression of Tensin 4 positively correlated with p-AKT in GC tissues and with GC progression, and was an independent risk factor for the prognosis of GC. Tensin 4 promoted the invasion and migration abilities of GC cells, but had no significant effect on GC cell proliferation. Tensin 4 promoted the occurrence of epithelial mesenchymal transition (EMT) through up-regulating the expression of p-AKT, p-GSK-3ß, and snail. Overall, this study suggests that the activation of AKT/GSK-3ß/Snail signaling pathway promoted by Tensin 4 plays an important role in the progression of GC. Therefore, Tensin 4 may serve as a potential target in GC treatment.


Assuntos
Adenocarcinoma/patologia , Biomarcadores Tumorais/análise , Transdução de Sinais/fisiologia , Neoplasias Gástricas/patologia , Tensinas/metabolismo , Idoso , Movimento Celular/fisiologia , Feminino , Regulação Neoplásica da Expressão Gênica/fisiologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fatores de Transcrição da Família Snail/metabolismo
7.
Pregnancy Hypertens ; 11: 18-25, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29523268

RESUMO

Abnormalities in the development of placental vasculature in early pregnancy and the failure of transformation of the spiral arteries are associated with the pathogenesis of preeclampsia. Sex hormones influence neovascularisation during pregnancy. However the profiling of estrogen and progesterone in preeclampsia is controversial. In this study we investigated the serum levels of estrogen and progesterone in women with preeclampsia. Blood samples were collected from 86 preeclamptic and 97 gestation-matched normotensive pregnancies. The levels of 17ß-estradiol (E2), progesterone and 2-methoxyestradiol (2-ME) in serum were measured. In addition, the levels of E2 and progesterone in conditioned media from preeclamptic or normotensive term placental explant cultures or placental explants that had been treated with hydrogen peroxide (H2O2) were measured. The expression of estrogen receptors (ER) and progesterone receptors (PR) in preeclamptic and control placentae were measured by immunohistochemistry. The serum levels of E2, progesterone and 2-ME were significantly reduced in women with preeclampsia compared to controls. There was no difference in the serum levels of E2 and progesterone between severe and mild or between early-onset and late-onset preeclampsia as well as between preeclampsia with and without fetal growth restriction (FGR). The levels of E2 and progesterone in preeclamptic placental explants cultures were significantly lower than in normotensive term placental explant cultures. Treatment with H2O2 was found to be associated with a reduction in E2 production by the placenta. We demonstrated lower levels of estrogen in preeclampsia and speculate that this reduction may be due to the impairment of placental function in preeclampsia.


Assuntos
Estradiol/análogos & derivados , Placenta/metabolismo , Pré-Eclâmpsia/sangue , Progesterona/sangue , 2-Metoxiestradiol , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Meios de Cultivo Condicionados/metabolismo , Regulação para Baixo , Estradiol/sangue , Feminino , Retardo do Crescimento Fetal/sangue , Retardo do Crescimento Fetal/diagnóstico , Retardo do Crescimento Fetal/fisiopatologia , Humanos , Peróxido de Hidrogênio/farmacologia , Placenta/efeitos dos fármacos , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/fisiopatologia , Gravidez , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Índice de Gravidade de Doença , Técnicas de Cultura de Tecidos , Tirosina/análogos & derivados , Tirosina/metabolismo , Adulto Jovem
8.
Oncotarget ; 8(53): 90897-90904, 2017 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-29207611

RESUMO

It is well-known that the clinical outcomes are different between type 1 (estrogen dependent) and type 2 (estrogen independent) endometrial cancer. Studies have suggested that the estrogen receptor (ER) is positively correlated with endometrial cancer survival, however we previously reported that there is no difference in the positivity of ER as well as sex hormone levels between subtypes of cancer. G-protein-coupled receptor-30 (GPR 30), an alternative estrogen receptor has been suggested to be negatively correlated with clinical outcomes of endometrial cancer. In this study we investigated whether the positivity of GPR30 is different between subtypes of cancer. The immunostaining of GPR30 and ER was examined and analysed in 128 cases taking into account menopausal status. Overall, 105 (82%) cases were GPR30 positive and 118 (92%) cases were ER positive. The positivity of GPR30 in type 1 endometrial cancer (83%) was not statistically different to type 2 endometrial cancer (78%). In addition, intensity of immunostaining of GPR30 in type 1 endometrial cancer was also not different to type 2 endometrial cancer quantified by semi-quantitative analysis (p = 0.268). Menopausal status was not associated with the positivity of GPR30 in both type 1 and type 2 endometrial cancer. Furthermore, the positivity and intensity of immunostaining of GPR30 were not correlated with the positivity and intensity of immunostaining of ER in endometrial cancer (p = 0.689). Our data further confirm that type 2 endometrial cancer may not be completely estrogen independent, and suggest that type 1 and type 2 endometrial cancer may have similar pathogenesis.

9.
Cancer Invest ; 35(2): 85-91, 2017 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-28102711

RESUMO

Potential predictive biomarker(s) to respond to chemotherapy in gastric cancer are unclear. Excision repair cross-complementing 1 (ERCC1), a DNA repair enzyme, is associated with clinical outcomes in gastric cancer. Here, we investigated the expression of ERCC1 in gastric cancer with platinum-based chemotherapy after surgery, and the association between ERCC1 expression and clinical parameters was analyzed. Our data showed that high levels of ERCC1 expression were positively associated with resistance to platinum-based chemotherapy but not with lymph node metastasis and pathological stage. In addition, patients with resistance to platinum-based chemotherapy probably had lymph node metastasis and pathological stage.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Proteínas de Ligação a DNA/biossíntese , Endonucleases/biossíntese , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/enzimologia , Adulto , Idoso , Biomarcadores Tumorais/biossíntese , Quimioterapia Adjuvante , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Compostos Organoplatínicos/administração & dosagem , Estudos Retrospectivos , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia
10.
Sci Rep ; 6: 39744, 2016 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-28000774

RESUMO

The involvement of hormonal factors in developing endometrial cancer is well documented. In particular, excess or unopposed estrogen is a major risk factor. Endometrial cancer is divided into estrogen-dependent and estrogen-independent types. Studies suggested that the subtypes of endometrial cancer share many common risk factors. Whether the levels of sex hormones differ between types 1 and 2 endometrial cancer has not been investigated. In this study, levels of estrogen, progesterone, testosterone, follicle stimulating hormone (FSH) and luteinizing hormone (LH) were investigated between type 1 and type 2 endometrial cancer taking into account menopausal status and parity. The sex hormones levels and estrogen and progesterone receptors were measured in 187 women with endometrial cancer. The levels of estradiol (E2), progesterone, testosterone, FSH and LH were not different between the subtypes of endometrial cancer regardless of menopausal status. In addition, the sex hormones were not different between patients of different party regardless of the menopausal status. The majority of type 1 (96%) and type 2 (82%) endometrial cancers were estrogen and progesterone receptor positive. Our data suggest that type 2 endometrial cancer is not completely estrogen independent, and type 1 and type 2 endometrial cancers may have a similar pathogenesis.


Assuntos
Neoplasias do Endométrio/sangue , Hormônios Esteroides Gonadais/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Endométrio/classificação , Neoplasias do Endométrio/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo
11.
J Cancer ; 7(7): 831-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27162542

RESUMO

Ovarian cancer is the third most common gynaecological malignancy. Changes in circadian rhythms such as bright light exposure may affect female reproductive physiology. Night shift work is associated with higher risks of developing gynaecological cancers. In addition, the season of birth is also suggested as an important environmental risk factor for developing gynaecological cancers. Melatonin may play an important role in this association as a marker of circadian rhythms. Serum from 96 women with ovarian cancer and 40 healthy women were collected and the level of melatonin was measured. In addition 277 women with ovarian cancer and 1076 controls were retrospectively collected for season of birth analysis over seven years. The serum levels of melatonin were significantly lower in women with ovarian cancer compared with healthy women (p<0.05). However there was no difference in melatonin levels in perimenopausal and postmenopausal patients. In addition, there is no statistically significant difference in seasonal distribution of birth between ovarian cancer patients and the control group. The melatonin levels in ovarian cancer patients and controls were not associated with the season of birth. Our results demonstrate the lower serum levels of melatonin in ovarian cancer patients which may contribute to the pathogenesis of ovarian cancer. The incidence of ovarian cancer was not associated with the season of birth. The serum levels of melatonin do not appear to be associated with season of birth in ovarian cancer patients.

13.
Zhonghua Gan Zang Bing Za Zhi ; 16(7): 505-8, 2008 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-18647528

RESUMO

OBJECTIVE: To screen anti-c-Met Fab from a phage antibody library and identify its binding activity. METHODS: The expression of c-Met of HCC lines was identified by Western blot and immunofluorescence. Antibodies against c-Met were screened with immobilized antigen. After five rounds of panning, 30 randomly selected clones were identified by phage ELISA to select specific clones with high affinity. The positive clones were selected for Fab soluble expression in TOP10F and the binding activities were analysed in HCC lines. RESULTS: c-Met expressed in HCC membrane was confirmed by Western blot and immunofluorescence. A Fab fragment named AM2-26 with fine activity to c-Met was selected. AM2-26 binding specificity was confirmed by IP, FACS and immunofluorescence. CONCLUSION: The anti-c-Met Fab binding to c-Met in HCC provides a promising candidate for the biotherapy of hepatoma.


Assuntos
Anticorpos/imunologia , Anticorpos/isolamento & purificação , Proteínas Proto-Oncogênicas c-met/imunologia , Linhagem Celular Tumoral , Clonagem Molecular , Biblioteca Gênica , Humanos , Fragmentos Fab das Imunoglobulinas/imunologia , Região Variável de Imunoglobulina/imunologia , Biblioteca de Peptídeos , Proteínas Recombinantes de Fusão/imunologia
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