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1.
Bioorg Chem ; 143: 106997, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38029569

RESUMO

P-glycoprotein (P-gp) over-expression is a key factor in multi-drug resistance (MDR), which is a major factor in the failure of cancer treatment. P-gp inhibitors have been demonstrated to have powerful pharmacological properties and may be used as a therapeutic approach to overcome the MDR in cancer cells. Combining clinical investigations with biochemical and computational research may potentially lead to a clearer understanding of the pharmacological properties and the mechanisms of action of these P-gp inhibitors. The task of turning these discoveries into effective therapeutic candidates for a variety of malignancies, including resistant and metastatic kinds, falls on medicinal chemists. A variety of P-gp inhibitors with great potency, high selectivity, and minimal toxicity have been identified in recent years. The latest advances in drug design, characterization, structure-activity relationship (SAR) research, and modes of action of newly synthesized, powerful small molecules P-gp inhibitors over the previous ten years are highlighted in this review. P-gp transporter over-expression has been linked to MDR, therefore the development of P-gp inhibitors will expand our understanding of the processes and functions of P-gp-mediated drug efflux, which will be helpful for drug discovery and clinical cancer therapies.


Assuntos
Antineoplásicos , Antineoplásicos/farmacologia , Antineoplásicos/química , Resistencia a Medicamentos Antineoplásicos , Relação Estrutura-Atividade , Resistência a Múltiplos Medicamentos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP
2.
Bioorg Chem ; 149: 107487, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38805910

RESUMO

The peel of Trichosanthes kirilowii Maxim, is considered one of the primary sources for Trichosanthis pericarpium in traditional Chinese medicine, exhibiting lipid-lowering properties. The impact on hyperlipidemia mice of the crude polysaccharide from the peel of T. Kirilowii (TRP) was investigated in this study. The findings revealed that TRP exhibited a significant improvement in hepatic lipid deposition. Moreover, it significantly decreased serum levels of TC, TG, and LDL-C, while concurrently increasing HDL-C. 16S rRNA amplicon sequencing technique revealed that TRP group exhibited an increased relative abundance of Actinobacteria, a down-regulated relative abundance of Ruminiclostridium, and an up-regulated relative abundance of Ileibacterium. Therefore, TRP might play a role in anti-hyperlipidemia through regulation of the intestinal milieu and enhancement of microbial equilibrium. Consequently, targeted fractionation of TRP resulted in the isolation of a homogeneous acidic polysaccharide termed TRP-1. The TRP-1 polysaccharide, with an average molecular weight of 1.00 × 104 Da, and was primarily composed of Rha, GlcA, GalA, Glc, Gal and Ara. TRP-1 possessed a backbone consisting of alternating connections between â†’ 6)-α-Galp-(1 â†’ 4)-α-Rhap-(1 â†’ 6)-α-Galp-(2 â†’ 6)-ß-Galp-(1 â†’ 6)-α-Galp-(2 â†’ 6)-ß-Galp-(1 â†’ units and branched chain containing â†’ 6)-α-Glcp-(1→, 2,4)-ß-Glcp-(1, and â†’ 4)-α-GlapA-(1→. Both TRP and TRP-1 exhibited significant disruption of cholesterol micelles, highlighting their potential as lipid-lowering agents that effectively inhibit cholesterol absorption pathways.


Assuntos
Colesterol , Microbioma Gastrointestinal , Hiperlipidemias , Polissacarídeos , Trichosanthes , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Trichosanthes/química , Camundongos , Hiperlipidemias/tratamento farmacológico , Polissacarídeos/farmacologia , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Colesterol/metabolismo , Colesterol/sangue , Hipolipemiantes/farmacologia , Hipolipemiantes/química , Hipolipemiantes/isolamento & purificação , Masculino , Estrutura Molecular , Relação Estrutura-Atividade , Relação Dose-Resposta a Droga
3.
Nucleic Acids Res ; 50(22): 12979-12996, 2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36533443

RESUMO

Aggregation of the microtubule-associated protein tau characterizes tauopathies, including Alzheimer's disease and frontotemporal lobar degeneration (FTLD-Tau). Gene expression regulation of tau is complex and incompletely understood. Here we report that the human tau gene (MAPT) generates two circular RNAs (circRNAs) through backsplicing of exon 12 to either exon 7 (12→7 circRNA) or exon 10 (12→10 circRNA). Both circRNAs lack stop codons. The 12→7 circRNA contains one start codon and is translated in a rolling circle, generating a protein consisting of multimers of the microtubule-binding repeats R1-R4. For the 12→10 circRNA, a start codon can be introduced by two FTLD-Tau mutations, generating a protein consisting of multimers of the microtubule-binding repeats R2-R4, suggesting that mutations causing FTLD may act in part through tau circRNAs. Adenosine to inosine RNA editing dramatically increases translation of circRNAs and, in the 12→10 circRNA, RNA editing generates a translational start codon by changing AUA to AUI. Circular tau proteins self-aggregate and promote aggregation of linear tau proteins. Our data indicate that adenosine to inosine RNA editing initiates translation of human circular tau RNAs, which may contribute to tauopathies.


Assuntos
Tauopatias , Proteínas tau , Humanos , Adenosina/metabolismo , Códon de Iniciação , Inosina/metabolismo , RNA/genética , RNA/metabolismo , Edição de RNA , RNA Circular/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismo , Tauopatias/genética , Tauopatias/metabolismo
4.
Chin J Cancer Res ; 36(3): 282-297, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38988485

RESUMO

Objective: The clinical significance of homologous recombination deficiency (HRD) in breast cancer, ovarian cancer, and prostate cancer has been established, but the value of HRD in non-small cell lung cancer (NSCLC) has not been fully investigated. This study aimed to systematically analyze the HRD status of untreated NSCLC and its relationship with patient prognosis to further guide clinical care. Methods: A total of 355 treatment-naïve NSCLC patients were retrospectively enrolled. HRD status was assessed using the AmoyDx Genomic Scar Score (GSS), with a score of ≥50 considered HRD-positive. Genomic, transcriptomic, tumor microenvironmental characteristics and prognosis between HRD-positive and HRD-negative patients were analyzed. Results: Of the patients, 25.1% (89/355) were HRD-positive. Compared to HRD-negative patients, HRD-positive patients had more somatic pathogenic homologous recombination repair (HRR) mutations, higher tumor mutation burden (TMB) (P<0.001), and fewer driver gene mutations (P<0.001). Furthermore, HRD-positive NSCLC had more amplifications in PI3K pathway and cell cycle genes, MET and MYC in epidermal growth factor receptor (EGFR)/anaplastic lymphoma kinase (ALK) mutant NSCLC, and more PIK3CA and AURKA in EGFR/ALK wild-type NSCLC. HRD-positive NSCLC displayed higher tumor proliferation and immunosuppression activity. HRD-negative NSCLC showed activated signatures of major histocompatibility complex (MHC)-II, interferon (IFN)-γ and effector memory CD8+ T cells. HRD-positive patients had a worse prognosis and shorter progression-free survival (PFS) to targeted therapy (first- and third-generation EGFR-TKIs) (P=0.042). Additionally, HRD-positive, EGFR/ALK wild-type patients showed a numerically lower response to platinum-free immunotherapy regimens. Conclusions: Unique genomic and transcriptional characteristics were found in HRD-positive NSCLC. Poor prognosis and poor response to EGFR-TKIs and immunotherapy were observed in HRD-positive NSCLC. This study highlights potential actionable alterations in HRD-positive NSCLC, suggesting possible combinational therapeutic strategies for these patients.

5.
Phys Rev Lett ; 131(11): 116002, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37774302

RESUMO

The extremely overdoped cuprates are generally considered to be Fermi liquid metals without exotic orders, whereas the underdoped cuprates harbor intertwined states. Contrary to this conventional wisdom, using Cu L_{3}-edge and O K-edge resonant x-ray scattering, we reveal a charge order (CO) correlation in overdoped La_{2-x}Sr_{x}CuO_{4} (0.35≤x≤0.6) beyond the superconducting dome. This CO has a periodicity of ∼6 lattice units with correlation lengths of ∼20 lattice units. It shows similar in-plane momentum and polarization dependence and dispersive excitations as the CO of underdoped cuprates, but its maximum intensity differs along the c direction and persists up to 300 K. This CO correlation cannot be explained by the Fermi surface instability and its origin remains to be understood. Our results suggest that CO is prevailing in the overdoped metallic regime and requires a reassessment of the picture of overdoped cuprates as weakly correlated Fermi liquids.

6.
Nephrology (Carlton) ; 28(3): 159-167, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36564906

RESUMO

AIM: To investigate the gender and socioeconomic disparities in the global burden of chronic kidney disease (CKD) due to glomerulonephritis from 1990 to 2019. METHODS: Data were extracted from the global burden of diseases (GBD) 2019 study, including incidence, prevalence and disability-adjusted life-years (DALYs). Estimated annual percentage changes (EAPCs) were calculated to quantify the temporal trends in age-standardized rate (ASR) of CKD due to glomerulonephritis. Paired t-test, paired Wilcoxon signed-rank test and Spearman correlation were performed to analyse the association and gender disparity in CKD due to glomerulonephritis. RESULTS: Globally, incident cases of CKD due to glomerulonephritis increased 81% from 9 557 397 in 1990 to 17 308 071 in 2019. The age-standardized incidence rate increased by 1.47 compared with 1990 and DALYs increased by 1.35 compared with 1990 (per 100 000). The number of patients with CKD due to glomerulonephritis in low-middle SDI (3829917) and middle SDI (6268817) regions accounts for more than 55% of the total cases. CKD due to glomerulonephritis caused a higher burden including the incidence rate (p < .0001) and DALY rate (p < .0001) in men compared to women. The age-standardized DALY rate was negatively correlated with SDI (ρ = -0.64, p < .001). In the analysis of risk factors for DALYs, male individuals had a larger burden of hypertension, high BMI and high sodium diet in the DALY rates than female subjects. CONCLUSION: The burden of CKD due to glomerulonephritis was more skewed towards developing and less developed economies and differed by gender, so certain nations should implement far more focused and targeted policies.


Assuntos
Insuficiência Renal Crônica , Disparidades Socioeconômicas em Saúde , Humanos , Masculino , Feminino , Anos de Vida Ajustados por Qualidade de Vida , Saúde Global , Carga Global da Doença , Incidência
7.
Acta Neuropathol ; 144(1): 27-44, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35697880

RESUMO

Limbic-predominant age-related TDP-43 encephalopathy neuropathologic change (LATE-NC) and Alzheimer's disease neuropathologic change (ADNC) are each associated with substantial cognitive impairment in aging populations. However, the prevalence of LATE-NC across the full range of ADNC remains uncertain. To address this knowledge gap, neuropathologic, genetic, and clinical data were compiled from 13 high-quality community- and population-based longitudinal studies. Participants were recruited from United States (8 cohorts, including one focusing on Japanese-American men), United Kingdom (2 cohorts), Brazil, Austria, and Finland. The total number of participants included was 6196, and the average age of death was 88.1 years. Not all data were available on each individual and there were differences between the cohorts in study designs and the amount of missing data. Among those with known cognitive status before death (n = 5665), 43.0% were cognitively normal, 14.9% had MCI, and 42.4% had dementia-broadly consistent with epidemiologic data in this age group. Approximately 99% of participants (n = 6125) had available CERAD neuritic amyloid plaque score data. In this subsample, 39.4% had autopsy-confirmed LATE-NC of any stage. Among brains with "frequent" neuritic amyloid plaques, 54.9% had comorbid LATE-NC, whereas in brains with no detected neuritic amyloid plaques, 27.0% had LATE-NC. Data on LATE-NC stages were available for 3803 participants, of which 25% had LATE-NC stage > 1 (associated with cognitive impairment). In the subset of individuals with Thal Aß phase = 0 (lacking detectable Aß plaques), the brains with LATE-NC had relatively more severe primary age-related tauopathy (PART). A total of 3267 participants had available clinical data relevant to frontotemporal dementia (FTD), and none were given the clinical diagnosis of definite FTD nor the pathological diagnosis of frontotemporal lobar degeneration with TDP-43 inclusions (FTLD-TDP). In the 10 cohorts with detailed neurocognitive assessments proximal to death, cognition tended to be worse with LATE-NC across the full spectrum of ADNC severity. This study provided a credible estimate of the current prevalence of LATE-NC in advanced age. LATE-NC was seen in almost 40% of participants and often, but not always, coexisted with Alzheimer's disease neuropathology.


Assuntos
Doença de Alzheimer , Demência Frontotemporal , Doenças do Sistema Nervoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/genética , Amiloide , Autopsia , Proteínas de Ligação a DNA , Humanos , Masculino , Placa Amiloide/patologia
8.
Inorg Chem ; 61(5): 2595-2602, 2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35061382

RESUMO

Organic-inorganic hybrid metal halides have recently attracted attention in the global research field for their bright light emission, tunable photoluminescence wavelength, and convenient synthesis method. This study reports the detailed properties of (C10H16N)2MnBr4, which emits bright green light with a high photoluminescence quantum yield. Results of powder X-ray diffraction, photoluminescence, thermogravimetric analysis, and Raman spectra show the phase transition of (C10H16N)2MnBr4 at 430 K. This phase transition was identified as the solid to liquid state of (C10H16N)2MnBr4. Moreover, the pressure- and temperature-induced relationship between structural and optical properties in (C10H16N)2MnBr4 can be identified. This investigation provides deep insights into the luminescent properties of metal halide crystals and promotes further research.

9.
J Synchrotron Radiat ; 27(Pt 4): 979-987, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33566007

RESUMO

Angle-dependent 2p3d resonant inelastic X-ray scattering spectra of a LaCoO3 single crystal and a 55 nm LaCoO3 film on a SrTiO3 substrate are presented. Theoretical calculation shows that, with ∼20 meV resolved Co 2p3d resonant inelastic X-ray scattering (RIXS), the excited states of the isotropic 1A1g(Oh) ground state are split by 3d spin-orbit coupling, which can be distinguished via their angular dependence. However, strong self-absorption and saturation effects distort the spectra of the LaCoO3 single crystal and limit the observation of small angular dependence. In contrast, the RIXS on 55 nm LaCoO3 shows less self-absorption effects and preserves the angular dependence of the excited states.

10.
Phys Chem Chem Phys ; 20(6): 4554-4562, 2018 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-29376165

RESUMO

Two isostructural cobalt containing polyoxometalate water oxidation catalysts, [Co4(H2O)2(α-PW9O34)2]10- (Co4P2) and [Co4(H2O)2(α-VW9O34)2]10- (Co4V2), exhibit large differences in their catalytic performance. The substitution of phosphorus centers in Co4P2 with redox-active vanadium centers in Co4V2 leads to electronic structure modifications. Evidence for the significance of the vanadium centers to catalysis, predicted by theory, was found from soft X-ray absorption (XAS) and resonant inelastic X-ray scattering (RIXS). The XAS and RIXS spectra determine the electronic structure of the cobalt and vanadium sites in the pre-reaction state of both Co4V2 and Co4P2. High-energy resolution RIXS results reveal that Co4V2 possesses a smaller ligand field within the tetra-cobalt core and a cobalt-to-vanadium charge transfer band. The differences in electronic structures offer insights into the enhanced catalysis of Co4V2.

11.
Inorg Chem ; 55(20): 10152-10160, 2016 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-27673751

RESUMO

The Co 2p3/2 X-ray absorption spectroscopy and high-energy-resolution (∼0.09 eV fwhm) 2p3d resonant inelastic X-ray scattering (RIXS) spectra of the single-cobalt-centered polyoxometalate K5H[CoW12O40]·xH2O were measured. The low-energy dd transition features at 0.55 eV, unmeasurable with ultraviolet-visible (UV/vis) spectroscopy, were experimentally revealed in 2p3d RIXS spectra. RIXS simulations based on ligand-field multiplet theory were performed to assess the potential cobalt tetragonal symmetry distortion, which is described with the ligand-field parameters 10Dq (-0.54 eV), Ds (-0.08 eV), and Dt (0.005 eV). Because 2p3d RIXS probes not only the optical spin-allowed transitions but also the spin-forbidden transitions, we show that the current 2p3d RIXS simulation enables a series of dd feature assignments with higher accuracy than those from previous optical data. Furthermore, by wave-function decomposition analyses, we demonstrate the more realistic and detailed origins of a few lowest dd transitions using both one-electron-orbital and term-symbol descriptions.

12.
J Environ Manage ; 169: 67-77, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26722715

RESUMO

The total emission control target of water pollutants (e.g., COD and NH4-N) for a certain industrial sector can be predicted and analysed using the popular technology-based bottom-up modelling. However, this methodology has obvious uncertainty regarding the attainment of mitigation targets. The primary uncertainty comes from macro-production, pollutant reduction roadmap, and technical parameters. This research takes the paper and pulp industry in China as an example, and builds 5 mitigation scenarios via different combinations of raw material structure, scale structure, procedure mitigation technology, and end-of-pipe treatment technology. Using the methodology of uncertainty analysis via Monte Carlo, random sampling was conducted over a hundred thousand times. According to key parameters, sensitive parameters that impact total emission control targets such as industrial output, technique structure, cleaner production technology, and end-of-pipe treatment technology are discussed in this article. It appears that scenario uncertainty has a larger influence on COD emission than NH4-N, hence it is recommended that a looser total emission control target for COD is necessary to increase its feasibility and availability while maintaining the status quo of NH4-N. Consequently, from uncertainty analysis, this research recognizes the sensitive products, techniques, and technologies affecting industrial water pollution.


Assuntos
Monitoramento Ambiental/métodos , Indústrias , Papel , Incerteza , Poluentes da Água/análise , China , Resíduos Industriais/análise , Método de Monte Carlo , Poluição da Água/análise
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(9): 2978-83, 2016 Sep.
Artigo em Zh | MEDLINE | ID: mdl-30085490

RESUMO

A new kind of imitation of turquoise named "Violet" and "White buffalo" which is a type of associated mineral of turquoise have appeared on the market recently and are becoming increasingly popular. Conventional instruments, X-ray fluorescence spectrometer, Infrared spectrometer, X-ray powder diffraction, Scanning electronic microscope, UV-Vis have been employed to discuss the gemmological characteristics of this kind of imitation of turquoise in this paper, to study their chemical composition, mineral composition, microstructure, spectral characteristics and color emerging mechanism. The X-ray fluorescence spectrum shows that the chemical composition of the sample is complicated. The basic elements of different-colour samples are basically identical which contains of Ca, Al, P, Cu, Si, K, Fe, Ba. It can be deduced from the intensity of infrared absorption bend that the major anion group of this kind of imitation of tuequoise is PO3-4. The analysis for X-ray powder diffraction data indicated that the major mineral of the sample is crandallite and woodhouseite. Meanwhile, the scanning electron microscopy showed that the structure of the dense sample is determined by numerous of scaly, leaf-shaped and irregular granular aggregates. With the study of absorption spectrum, the conclusion is drawn that Fe3+ electronic transitions are the main factor for coloring of the sample and color varies with the content of Fe3+.

14.
Zhonghua Zhong Liu Za Zhi ; 37(10): 742-8, 2015 Oct.
Artigo em Zh | MEDLINE | ID: mdl-26813592

RESUMO

OBJECTIVE: The aim of this study was to establish a standardized protocol for detection of ALK protein expression and gene fusion in cytologic specimens. METHODS: Lung adenocarcinoma cytologic specimens were collected from seven hospitals in Beijing city. A detection protocol for ALK protein expression and gene fusion was designed according to the results of comparative experiment. Ventana immunohistochemical (IHC) ALK(D5F3) detecting ALK protein expression was performed in 203 prepared formalin-fixed paraffin-embedded (FFPE) cell blocks. ALK gene fusion in 98 EGFR gene wild type cytologic specimens and in 4 bronchoalveolar lavage fluid (BL) samples was detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR). ALK gene fusion in the Ventana IHC ALK (D5F3) positive samples was further tested by fluorescence in situ hybridization (FISH). Six patients with ALK IHC-positive result were followed up to analyze the responses of crizotinib therapy. Comparative experiments: (1) Comparison of the results of 4% neutral buffered formalin fixed for different time (24 h, 48 h, 72 h) on the Ventana IHC ALK (D5F3) staining was conducted in two cases of IHC ALK positive FFPE cell blocks; (2) Comparing qRT-PCR results for ALK fusion in samples from FFPE cell blocks and cytospin prepared slides in 10 cases of lung adenocarcinoma cytologic specimens. RESULTS: Among the specimens examined using the standardized protocol recommended by this study, 229 cases of cytologic specimens met the diagnostic criteria of lung adenocarcinoma. Among them, 207 cases obtained ALK gene test results (by at least one method), with an ALK test ratio of 90.4% (207/229). FFPE cell blocks were successfully prepared in 203 cases, Ventana IHC ALK (D5F3) were successfully performed in all the 203 FFPE cell blocks (100%), and the ALK protein positive detection rate was 10.3% (21/203). ALK fusion was tested in 98 FFPE cytologic samples of EGFR wild types by qRT-PCR, and 96 out of 98 (97.96%) cytologic samples were successfully performed.18 out of 19 IHC ALK-positive cases were verified to be of ALK fusion status by qRT-PCR. The concordance rate was 94.7% (Kappa=0.967, P<0.001) between Ventana IHC ALK (D5F3) and qRT-PCR, and the sensitivity of the Ventana IHC ALK (D5F3) assay compared with qRT-PCR was 100% and the specificity was 98.7%. FISH assay was used to verify the positive cases detected by Ventana IHC ALK (D5F3) staining. Two cases of low tumor cell content FFPE samples obtained indefinite results by FISH test. The six patients with positive ALK protein expression received crizotinib therapy, and 5 paitents got treated effectively. For two ALK IHC positive cases, which were 4% neutral buffered formalin fixed for 72 h, the result of Ventana IHC ALK (D5F3) staining became weakened obviously and uneven. In 10 cases of samples, total RNA was extracted from FFPE cytologic sections and cytospin prepared slides, and the results of qRT-PCR test and ALK gene fusion showed good concordance. CONCLUSIONS: The standardized protocol recommended in this study expands the detection types and quantity of cytologic specimens for ALK protein expression and gene fusion and increased the detection rate. Ventana IHC ALK (D5F3) is a reliable method for detecting ALK protein expression in FFPE cell blocks. The pathologic quality control procedure prior to Ventana IHC ALK (D5F3) is crucial for the accuracy of testing the ALK gene status. When FFPE cell blocks could not be prepared or prepared unsuccessfully from the cytologic specimens, qRT-PCR may be an alternative option for the detection of ALK gene fusion.


Assuntos
Adenocarcinoma/enzimologia , Adenocarcinoma/genética , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Fusão Gênica , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Crizotinibe , Genes erbB-1 , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteômica , Pirazóis/uso terapêutico , Piridinas/uso terapêutico , Sensibilidade e Especificidade
15.
J Biol Chem ; 288(15): 10427-39, 2013 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-23457335

RESUMO

The Ca(2+)-permeable transient receptor potential vanilloid subtype 4 (TRPV4) channel mediates crucial physiological functions, such as calcium signaling, temperature sensing, and maintaining cell volume and energy homeostasis. Noticeably, most disease-causing genetic mutations are concentrated in the cytoplasmic domains. In the present study, we focused on the role of the TRPV4 C terminus in modulating protein folding, trafficking, and activity. By examining a series of C-terminal deletions, we identified a 20-amino acid distal region covering residues 838-857 that is critical for channel folding, maturation, and trafficking. Surface biotinylation, confocal imaging, and fluorescence-based calcium influx assay demonstrated that mutant proteins missing this region were trapped in the endoplasmic reticulum and unglycosylated, leading to accelerated degradation and loss of channel activity. Rosetta de novo structural modeling indicated that residues 838-857 assume a defined conformation, with Gly(849) and Pro(851) located at critical positions. Patch clamp recordings confirmed that lowering the temperature from 37 to 30 °C rescued channel activity of folding-defective mutants. Moreover, biochemical tests demonstrated that, in addition to participating in C-C interaction, the C terminus also interacts with the N terminus. Taken together, our findings indicate that the C-terminal region of TRPV4 is critical for channel protein folding and maturation, and the short distal segment plays an essential role in this process. Therefore, selectively disrupting the folding-sensitive region may present therapeutic potential for treating overactive TRPV4-mediated diseases, such as pain and skeletal dysplasias.


Assuntos
Modelos Moleculares , Dobramento de Proteína , Canais de Cátion TRPV/metabolismo , Sequência de Aminoácidos , Animais , Células HEK293 , Humanos , Camundongos , Mapeamento de Peptídeos/métodos , Estrutura Terciária de Proteína , Transporte Proteico/fisiologia , Deleção de Sequência , Canais de Cátion TRPV/química , Canais de Cátion TRPV/genética
16.
Zhonghua Zhong Liu Za Zhi ; 36(7): 516-21, 2014 Jul.
Artigo em Zh | MEDLINE | ID: mdl-25327657

RESUMO

OBJECTIVE: The aim of this study was to establish a standard protocol for detection of EGFR mutations in cytologic specimens. METHODS: 287 cytologic samples were collected from the patients who were suspected of having lung cancer at six hospitals in Beijing. A detection protocol for EGFR mutations was designed. Two comparative experiments were carried out for the coincidence in EGFR mutation rates between direct sequencing (Seq) and amplification refractory mutation system (ARMS) methods, and between 40 matched cytologic samples with formaldehyde-fixed paraffin embedded (FFPE) cytologic blocks and cytospin slides. RESULTS: Tumor cells were found in 236 out of 287 cases (82.2%, 236/287) . Among them, there were 31 cases (13.1%, 31/236) of low tumor cell content samples and 205 cases (86.9%, 205/236) of high tumor cell content samples. 180 cases in the high tumor cell content samples (87.8%, 180/205) were diagnosed to be consistent with NSCLC. 25 out of 194 cases were ruled out or indefinite to be diagnosed as NSCLC by immunohistochemistry. By direct sequencing, the mutation rate of EGFR was 27.8% (50/180) in NSCLC samples and 28.2% (50/177) in adenocarcinoma samples (high tumor content samples) . By ARMS, the mutation rate of EGFR was 45.6% (82/180) in NSCLC samples and 46.3% (82/177) in adenocarcinoma samples (high tumor content samples). The EGFR mutation rate in low tumor content samples was 38.7% (12/31) , there was no significant difference in EGFR mutation rates between the groups of low tumor cell content samples and high tumor cell content samples (P = 0.12). The concordance rate of EGFR mutation rates was 100% between scraping tumor cells from slides samples and from FFEP blocks in the 40 matched samples. Forty-eight out of 180 definitive NSCLC patients received Gefitinib therapy. The FPS was 12 months in the gefitinib-treated ARMS⁺ group and 2 months in the ARMS⁻ group (P < 0.001), and the OS was 19 months in the gefitinib-treated ARMS⁺ group and 7 months in the ARMS⁻ group (P = 0.003), but no significant differences were found in the efficacy (PFS and OS) of Gefitinib between Seq⁺ and Seq⁻ groups (P = 0.227, P = 0.510, respectively), and Seq⁺/ARMS⁺ and Seq⁻/ARMS⁺ groups (P = 0.354, P = 0.334, respectively). CONCLUSIONS: The detection protocol for EGFR mutations in cytological specimens introduced in this study is tested to be reliable and feasible. Pathological evaluation and immunohistochemistry are important in the detection procedure of EGFR mutations in cytologic specimens. High sensitivity methods should be selected for detection of EGFR mutations in cytologic samples.


Assuntos
Receptores ErbB/genética , Neoplasias Pulmonares/metabolismo , Adenocarcinoma/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Receptores ErbB/metabolismo , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiologia , Mutação , Taxa de Mutação , Reação em Cadeia da Polimerase
17.
Sheng Li Ke Xue Jin Zhan ; 45(6): 401-9, 2014 Dec.
Artigo em Zh | MEDLINE | ID: mdl-25872344

RESUMO

Transient receptor potential (TRP) channels are a super-family of nonselective cation channels that play critical roles in the responses to various environmental changes and stimuli. Over the past 10 years much progress has been made in the structural studies of TRP channels. To date, the structures of 5 full-length TRP channels and their 11 cytoplasmic domains have been determined. These structural insights enhance our understanding of TRP channel gating, assembly and regulation. In this review, the structures of TRP channels are summarized with an emphasis on the progress made during the last two years.


Assuntos
Canais de Potencial de Receptor Transitório/química
18.
Immun Inflamm Dis ; 12(1): e1165, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38270322

RESUMO

INTRODUCTION: Existing therapies of systemic lupus erythematosus (SLE) are efficacious only in certain patients. Developing new treatment methods is urgent. This meta-analysis aimed to evaluate the efficacy and safety of low-dose IL-2 (LD-IL-2). METHODS: According to published data from PubMed, Web of Science, Embase, ClinicalTrials.gov, MEDLINE, MEDLINE, Web of Knowledge, Cochrane Library, and FDA.gov, eight trials were included. RESULTS: After the LD-IL-2 treatment, 54.8% of patients had distinct clinical remission. The SRI-4 response rates were 0.819 (95% confidence interval [CI]: 0.745-0.894), and the SELENA-SLEDAI scores were significantly decreased (SMD = -2.109, 95% CI: [-3.271, -0.947], p < .001). Besides, the proportions of CD4+ T (SMD = 0.614, 95% CI: [0.250, 0.979], p = .001) and Treg cells (SMD = 1.096, 95% CI: [0.544, 1.649], p < .001) were increased dramatically after LD-IL-2 treatment, while there were no statistical differences in the proportions of CD8+ T cells, Th1 cells, Th2 cells, and Th17 cells (p > .05). Besides, the proportions of Th17 (SMD = 1.121, 95% CI: [0.709, 1.533], p < .001) and Treg (SMD = 0.655, 95% CI: [0.273, 1.038], p = .001) were significantly increased after receiving subcutaneously 0.5 million IU of LD-IL-2 treatment per day for 5 days, but there were no statistical differences in the proportions of Treg after receiving 1 million IU every other day subcutaneously of LD-IL-2 treatment. Injection site reaction and fever were common side effects of IL-2, which occurred in 33.1% and 14.4% of patients. No serious adverse events were reported. CONCLUSION: LD-IL-2 was promising and well-tolerated in treating SLE, which could promote Treg's proliferation and functional recovery. Injecting 0.5 million IU of IL-2 daily can better induce the differentiation of Treg cells and maintain immune homeostasis than injecting 1 million IU every other day.


Assuntos
Interleucina-2 , Lúpus Eritematoso Sistêmico , Humanos , Linfócitos T CD8-Positivos , Diferenciação Celular , Interleucina-2/uso terapêutico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Subpopulações de Linfócitos
19.
Hum Pathol ; 143: 42-49, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38052269

RESUMO

Trichorhinophalangeal syndrome type 1 (TRPS1) has been reported to be a sensitive and specific immunohistochemical (IHC) marker for breast carcinomas, especially when determining primary site of origin. However, there is limited data on TRPS1 expression in prostate and bladder cancers. A two-phase study was performed with 1) an exploratory cohort analyzing TRPS1 gene alterations in prostate, bladder, and breast carcinoma and TPRS1 mRNA expression data in prostate and bladder carcinoma; and 2) TRPS1 and GATA3 IHC in a confirmatory cohort in prostate, bladder, and breast carcinoma samples. Gene alterations were identified in a subset of breast, bladder, and prostate carcinomas and mRNA was consistently detected. In the IHC cohort, 183/210 (87.1 %) of breast, 22/69 (31.9 %) of prostate, and 20/73 (27.4 %) of urothelial carcinomas showed staining with TRPS1. Intermediate to high expression of TRPS1 was observed in 173/210 (82.8 %) of breast, 17/69 (24.6 %) of prostate, and 15/73 (20.5 %) of urothelial carcinomas. Furthermore, in prostate cancer, 26.9 % of pelvic lymph node metastases and 50 % in sites of distant metastases showed expression. Increased TRPS1 mRNA expression (p = 0.032) and IHC expression (p = 0.040) correlated with worse overall survival in bladder cancer. By comparison, GATA3 IHC stained 136/210 (64.8 %) of breast, 0/69 (0 %) of prostate, and 63/73 (93 %) of bladder carcinomas. Intermediate to high expression of GATA3 was seen in 131/210 (62.4 %) of breast and 63/73 (93 %) of bladder carcinomas. This study shows there is significant staining of TRPS1 in bladder and prostate cancers. As a result, comprehensive studies are needed to establish the true specificity of TRPS1 IHC stain across various tumor types before its widespread clinical adoption.


Assuntos
Adenocarcinoma , Neoplasias da Mama , Carcinoma de Células de Transição , Neoplasias da Próstata , Neoplasias da Bexiga Urinária , Masculino , Humanos , Carcinoma de Células de Transição/patologia , Neoplasias da Bexiga Urinária/patologia , Bexiga Urinária/patologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Próstata/patologia , Neoplasias da Mama/patologia , Adenocarcinoma/patologia , RNA Mensageiro , Músculos/metabolismo , Músculos/patologia , Fator de Transcrição GATA3/metabolismo , Proteínas Repressoras/genética
20.
J Pathol Inform ; 15: 100368, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38496781

RESUMO

Soft tissue tumors (STTs) pose diagnostic and therapeutic challenges due to their rarity, complexity, and morphological overlap. Accurate differentiation between benign and malignant STTs is important to set treatment directions, however, this task can be difficult. The integration of machine learning and artificial intelligence (AI) models can potentially be helpful in classifying these tumors. The aim of this study was to investigate AI and machine learning tools in the classification of STT into benign and malignant categories. This study consisted of three components: (1) Evaluation of whole-slide images (WSIs) to classify STT into benign and malignant entities. Five specialized soft tissue pathologists from different medical centers independently reviewed 100 WSIs, representing 100 different cases, with limited clinical information and no additional workup. The results showed an overall concordance rate of 70.4% compared to the reference diagnosis. (2) Identification of cell-specific parameters that can distinguish benign and malignant STT. Using an image analysis software (QuPath) and a cohort of 95 cases, several cell-specific parameters were found to be statistically significant, most notably cell count, nucleus/cell area ratio, nucleus hematoxylin density mean, and cell max caliper. (3) Evaluation of machine learning library (Scikit-learn) in differentiating benign and malignant STTs. A total of 195 STT cases (156 cases in the training group and 39 cases in the validation group) achieved approximately 70% sensitivity and specificity, and an AUC of 0.68. Our limited study suggests that the use of WSI and AI in soft tissue pathology has the potential to enhance diagnostic accuracy and identify parameters that can differentiate between benign and malignant STTs. We envision the integration of AI as a supportive tool to augment the pathologists' diagnostic capabilities.

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