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1.
Medicine (Baltimore) ; 102(52): e36344, 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38206740

RESUMO

This study aimed to investigate the diagnostic utility of percutaneous ultrasound-guided needle biopsy conjunction with GeneXpert MTB/RIF for epididymal tuberculosis. A retrospective analysis was conducted on the pathological and laboratory examinations of 20 patients with epididymal lesions undergoing ultrasound guided biopsy at Shandong Public Health Clinical Center. Laboratory examination included acid-fast staining, Mycobacterium tuberculosis culture by BACTEC MGIT 960, and GeneXpert MTB/RIF test. Diagnosis and complications were comprehensively analyzed. Among the 20 patients, 15 had epididymal tuberculosis and 5 had non-epididymal tuberculosis. Ten patients had granulomatous inflammation and necrotic tissues. The sensitivity and specificity of acid-fast staining, Mycobacterium tuberculosis culture, and GeneXpert MTB/RIF for the diagnosis of epididymis tuberculosis were 26.67% and 100.00%, 33.33% and 100.00%, and 86.67% and 100.00%, respectively. The diagnostic value analysis of the 3 detection techniques indicated that the GeneXpert MTB/RIF technique (Kappa = 0.765, Area under the curve (AUC) = 0.933) was superior to Mycobacterium tuberculosis culture (Kappa = 0.200, AUC = 0.667) and acid-fast staining (Kappa = 0.154, AUC = 0.633). Ultrasound-guided percutaneous biopsy is a safe procedure. The GeneXpert MTB/RIF test has high sensitivity, specificity, and superior AUC value, which are of great value in the diagnosis of epididymal tuberculosis and rifampicin resistance detection.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Masculino , Humanos , Rifampina/farmacologia , Mycobacterium tuberculosis/genética , Estudos Retrospectivos , Epididimo , Sensibilidade e Especificidade , Tuberculose/diagnóstico , Ultrassonografia de Intervenção , Biópsia por Agulha , Escarro/microbiologia
2.
Opt Express ; 30(12): 20859-20870, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-36224821

RESUMO

Highly emissive spaceborne blackbody radiation sources are important devices for infrared value traceability by providing accurate infrared radiation to calibrate infrared load. To meet the needs of the radiation calibration accuracy needed for infrared remote sensing, this paper proposes a highly emissive blackbody that uses cubic reflection and an absorption method based on light capture. An emissivity simulation based on ray tracing was carried out. The influences of specular reflection (SR), near specular reflection (NSR), and diffuse reflection (DR) on the emissivity of the blackbody were analyzed. Two blackbodies with NSR and DR were fabricated, simulated, and tested experimentally; the experimental and simulation results were consistent.

3.
Cell Res ; 32(11): 995-1007, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36151216

RESUMO

Chimeric antigen receptor (CAR)-T cell therapy against T cell malignancies faces major challenges including fratricide between CAR-T cells and product contamination from the blasts. Allogeneic CAR-T cells, generated from healthy donor T cells, can provide ready-to-use, blast-free therapeutic products, but their application could be complicated by graft-versus-host disease (GvHD) and host rejection. Here we developed healthy donor-derived, CD7-targeting CAR-T cells (RD13-01) with genetic modifications to resist fratricide, GvHD and allogeneic rejection, as well as to potentiate antitumor function. A phase I clinical trial (NCT04538599) was conducted with twelve patients recruited (eleven with T cell leukemia/lymphoma, and one with CD7-expressing acute myeloid leukemia). All patients achieved pre-set end points and eleven proceeded to efficacy evaluation. No dose-limiting toxicity, GvHD, immune effector cell-associated neurotoxicity or severe cytokine release syndrome (grade ≥ 3) were observed. 28 days post infusion, 81.8% of patients (9/11) showed objective responses and the complete response rate was 63.6% (7/11, including the patient with AML). 3 of the responding patients were bridged to allogeneic hematopoietic stem cell transplantation. With a median follow-up of 10.5 months, 4 patients remained in complete remission. Cytomegalovirus (CMV) and/or Epstein-Barr virus (EBV) reactivation was observed in several patients, and one died from EBV-associated diffuse large B-cell lymphoma (DLBCL). Expansion of CD7-negative normal T cells was detected post infusion. In summary, we present the first report of a Phase I clinical trial using healthy donor-derived CD7-targeting allogeneic CAR-T cells to treat CD7+ hematological malignancies. Our results demonstrated the encouraging safety and efficacy profiles of the RD13-01 allogeneic CAR-T cells for CD7+ tumors.


Assuntos
Infecções por Vírus Epstein-Barr , Doença Enxerto-Hospedeiro , Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Receptores de Antígenos Quiméricos , Humanos , Doença Enxerto-Hospedeiro/etiologia , Receptores de Antígenos Quiméricos/genética , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4 , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Neoplasias Hematológicas/terapia , Neoplasias Hematológicas/complicações , Leucemia Mieloide Aguda/patologia
4.
Mol Cell Biochem ; 477(4): 1207-1216, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35084672

RESUMO

In breast cancer, it is the resulting metastasis that is the primary cause of fatality. pH regulatory proteins and the tumor microenvironment play an important role in metastasis of cancer cells and acid-extruding proteins are critical in this process. There are several types of breast cancer and triple-negative breast cancer tends to be more metastatic and invasive and is itself is composed of several types. MDA-MB-468 are a triple-negative breast cancer cell line and are classified as basal-like and basal tumors account for up to 15% of breast cancers. Here we examined the effect of removal of the acid-extruding protein, the Na+/H+ exchanger isoform one, from MDA-MB-468 cells. NHE1 was deleted from these cells using the CRISPR/Cas9 system. Western blotting and measurement of activity confirmed the absence of the protein. In wounding/cell migration experiments, deletion of NHE1 reduced the rate of cell migration in the presence of low- or high-serum concentrations. Anchorage-dependent colony formation was also greatly reduced by deletion of the NHE1 protein. Cell proliferation was not affected by knockout of NHE1. The results demonstrate that NHE1 has an important role in migration and invasion of basal-like triple-negative breast cancer cells.


Assuntos
Movimento Celular , Proteínas de Neoplasias/metabolismo , Trocador 1 de Sódio-Hidrogênio/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Feminino , Humanos , Células MCF-7 , Invasividade Neoplásica , Proteínas de Neoplasias/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Trocador 1 de Sódio-Hidrogênio/genética , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia
5.
Int J Mol Sci ; 22(24)2021 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-34948058

RESUMO

Prostate cancer is a leading cause of cancer-associated deaths in men over 60 years of age. Most patients are killed by tumor metastasis. Recent evidence has implicated a role of the tumor microenvironment and urokinase plasminogen activator (uPA) in cancer cell migration, invasion, and metastasis. Here, we examine the role of the Na+/H+ exchanger isoform 1 (NHE1) and uPA in DU 145 prostate cancer cell migration and colony formation. Knockout of NHE1 reduced cell migration. The effects of a series of novel NHE1/uPA hexamethylene-amiloride-based inhibitors with varying efficacy towards NHE1 and uPA were examined on prostate cancer cells. Inhibition of NHE1-alone, or with inhibitors combining NHE1 or uPA inhibition-generally did not prevent prostate cancer cell migration. However, uPA inhibition-but not NHE1 inhibition-prevented anchorage-dependent colony formation. Application of inhibitors at concentrations that only saturate uPA inhibition decreased tumor invasion in vivo. The results suggest that while knockout of NHE1 affects cell migration, these effects are not due to NHE1-dependent proton translocation. Additionally, while neither NHE1 nor uPA activity was critical in cell migration, only uPA activity appeared to be critical in anchorage-dependent colony formation of DU 145 prostate cancer cells and invasion in vivo.


Assuntos
Proteínas de Membrana/metabolismo , Neoplasias da Próstata/metabolismo , Trocador 1 de Sódio-Hidrogênio/genética , Trocador 1 de Sódio-Hidrogênio/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Técnicas de Inativação de Genes , Humanos , Masculino , Neoplasias da Próstata/genética , Microambiente Tumoral , Regulação para Cima
6.
Int J Clin Exp Pathol ; 14(8): 908-914, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34527134

RESUMO

The brain, especially the hippocampus, is sensitive to damage caused by anoxic chemicals. In this study, we established a rat model of acrylonitrile poisoning with administration by gavage, aiming to determine the influence of acrylonitrile on rat cerebral nerve cells. Transmission electron microscopy observation and TdT-mediated dUTP nick-end labelling (TUNEL) staining were used to explore preliminarily the apoptotic changes of cerebral nerve cells. The pathogenesis revealed by transmission electron microscopy indicated that apoptosis in the control group was more serious than that of the exposure groups. The results of TUNEL staining showed the apoptotic rate was significantly higher in the control group than that of other exposure groups. All the results indicated that acrylonitrile can inhibit the apoptosis of rat cerebral nerve cells, which is closely related to its animal carcinogenicity.

7.
Biochim Biophys Acta Biomembr ; 1863(9): 183648, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-33992631

RESUMO

Mammalian Na+/H+ exchanger isoform one (NHE1) is a plasma membrane protein responsible for pH regulation in mammalian cells. Excess activity of the protein promotes heart disease and is a trigger of metastasis in cancer. Inhibitors of the protein exist but problems in specificity have delayed their clinical application. Here we examined amino acids involved in two modeled inhibitor binding sites (A, B) in human NHE1. Twelve mutations (Asp159, Phe348, Ser351, Tyr381, Phe413, Leu465, Gly466, Tyr467, Leu468, His473, Met476, Leu481) were made and characterized. Mutants S351A, F413A, Y467A, L468A, M476A and L481A had 40-70% of wild type expression levels, while G466A and H473A expressed 22% ~ 30% of the wild type levels. Most mutants, were targeted to the cell surface at levels similar to wild type NHE1, approximately 50-70%, except for F413A and G466A, which had very low surface targeting. Most of the mutants had measurable activity except for D159A, F413A and G466A. Resistance to inhibition by EMD87580 was elevated in mutants F438A, L465A and L468A and reduced in mutants S351A, Y381A, H473A, M476A and L481A. All mutants with large alterations in inhibitory properties showed reduced Na+ affinity. The greatest changes in activity and inhibitor sensitivity were in mutants present in binding site B which is more closely associated with TM4 and C terminal of extracellular loop 5, and is situated between the putative scaffolding domain and transport domain. The results help define the inhibitor binding domain of the NHE1 protein and identify new amino acids involved in inhibitor binding.


Assuntos
Guanidinas/farmacologia , Trocadores de Sódio-Hidrogênio/antagonistas & inibidores , Sulfonas/farmacologia , Aminoácidos/antagonistas & inibidores , Aminoácidos/genética , Aminoácidos/metabolismo , Animais , Sítios de Ligação/efeitos dos fármacos , Células CHO , Cricetulus , Guanidinas/química , Modelos Moleculares , Mutação , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Trocadores de Sódio-Hidrogênio/genética , Trocadores de Sódio-Hidrogênio/metabolismo , Sulfonas/química
8.
Int J Mol Sci ; 22(6)2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33804289

RESUMO

The K+-sparing diuretic amiloride shows off-target anti-cancer effects in multiple rodent models. These effects arise from the inhibition of two distinct cancer targets: the trypsin-like serine protease urokinase-type plasminogen activator (uPA), a cell-surface mediator of matrix degradation and tumor cell invasiveness, and the sodium-hydrogen exchanger isoform-1 (NHE1), a central regulator of transmembrane pH that supports carcinogenic progression. In this study, we co-screened our library of 5- and 6-substituted amilorides against these two targets, aiming to identify single-target selective and dual-targeting inhibitors for use as complementary pharmacological probes. Closely related analogs substituted at the 6-position with pyrimidines were identified as dual-targeting (pyrimidine 24 uPA IC50 = 175 nM, NHE1 IC50 = 266 nM, uPA selectivity ratio = 1.5) and uPA-selective (methoxypyrimidine 26 uPA IC50 = 86 nM, NHE1 IC50 = 12,290 nM, uPA selectivity ratio = 143) inhibitors, while high NHE1 potency and selectivity was seen with 5-morpholino (29 NHE1 IC50 = 129 nM, uPA IC50 = 10,949 nM; NHE1 selectivity ratio = 85) and 5-(1,4-oxazepine) (30 NHE1 IC50 = 85 nM, uPA IC50 = 5715 nM; NHE1 selectivity ratio = 67) analogs. Together, these amilorides comprise a new toolkit of chemotype-matched, non-cytotoxic probes for dissecting the pharmacological effects of selective uPA and NHE1 inhibition versus dual-uPA/NHE1 inhibition.


Assuntos
Amilorida/farmacologia , Neoplasias da Mama/tratamento farmacológico , Trocador 1 de Sódio-Hidrogênio/genética , Ativador de Plasminogênio Tipo Uroquinase/genética , Amilorida/síntese química , Amilorida/química , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Diuréticos/síntese química , Diuréticos/química , Diuréticos/farmacologia , Feminino , Humanos , Modelos Moleculares , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Trocador 1 de Sódio-Hidrogênio/antagonistas & inibidores , Relação Estrutura-Atividade , Ativador de Plasminogênio Tipo Uroquinase/antagonistas & inibidores
9.
Clin Cancer Res ; 27(10): 2764-2772, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33627493

RESUMO

PURPOSE: Autologous chimeric antigen receptor T (CAR-T) cell therapy is an effective treatment for relapsed/refractory acute lymphoblastic leukemia (r/r ALL). However, certain characteristics of autologous CAR-T cells can delay treatment availability. Relapse caused by antigen escape after single-targeted CAR-T therapy is another issue. Therefore, we aim to develop CRISPR-edited universal off-the-shelf CD19/CD22 dual-targeted CAR-T cells as a novel therapy for r/r ALL. PATIENTS AND METHODS: In this open-label dose-escalation phase I study, universal CD19/CD22-targeting CAR-T cells (CTA101) with a CRISPR/Cas9-disrupted TRAC region and CD52 gene to avoid host immune-mediated rejection were infused in patients with r/r ALL. Safety, efficacy, and CTA101 cellular kinetics were evaluated. RESULTS: CRISPR/Cas9 technology mediated highly efficient, high-fidelity gene editing and production of universal CAR-T cells. No gene editing-associated genotoxicity or chromosomal translocation was observed. Six patients received CTA101 infusions at doses of 1 (3 patients) and 3 (3 patients) × 106 CAR+ T cells/kg body weight. Cytokine release syndrome occurred in all patients. No dose-limiting toxicity, GvHD, neurotoxicity, or genome editing-associated adverse events have occurred to date. The complete remission (CR) rate was 83.3% on day 28 after CTA101 infusion. With a median follow-up of 4.3 months, 3 of the 5 patients who achieved CR or CR with incomplete hematologic recovery (CR/CRi) remained minimal residual disease (MRD) negative. CONCLUSIONS: CRISPR/Cas9-engineered universal CD19/CD22 CAR-T cells exhibited a manageable safety profile and prominent antileukemia activity. Universal dual-targeted CAR-T cell therapy may offer an alternative therapy for patients with r/r ALL.


Assuntos
Antígenos CD19/imunologia , Sistemas CRISPR-Cas , Engenharia Genética , Imunoterapia Adotiva , Leucemia-Linfoma Linfoblástico de Células Precursoras B/terapia , Receptores de Antígenos Quiméricos/imunologia , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico/imunologia , Adulto , Resistencia a Medicamentos Antineoplásicos , Feminino , Edição de Genes , Humanos , Imunoterapia Adotiva/métodos , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/etiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/metabolismo , Receptores de Antígenos Quiméricos/genética , Recidiva , Linfócitos T/imunologia , Linfócitos T/metabolismo , Resultado do Tratamento
10.
Mol Cell Biochem ; 468(1-2): 13-20, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32130622

RESUMO

Mammalian Na+/H+ exchanger type I isoform (NHE1) is a ubiquitously expressed membrane protein that regulates intracellular pH (pHi) by removing one intracellular proton in exchange for one extracellular sodium ion. Abnormal activity of the protein occurs in cardiovascular disease and breast cancer. The purpose of this study is to examine the role of negatively charged amino acids of extracellular loop 3 (EL3) in the activity of the NHE protein. We mutated glutamic acid 217 and aspartic acid 226 to alanine, and to glutamine and asparagine, respectively. We examined effects on expression levels, cell surface targeting and activity of NHE1, and also characterized affinity for extracellular sodium and lithium ions. Individual mutation of these amino acids had little effect on protein function. However, mutation of both these amino acids together impaired transport, decreasing the Vmax for both Na+ and Li+ ions. We suggested that amino acids E217 and D226 form part of a negatively charged coordination sphere, which facilitates cation transport in the NHE1 protein.


Assuntos
Aminoácidos Acídicos/química , Proteínas de Transporte de Cátions/química , Proteínas de Transporte de Cátions/metabolismo , Membrana Celular/metabolismo , Trocadores de Sódio-Hidrogênio/química , Trocadores de Sódio-Hidrogênio/metabolismo , Aminoácidos Acídicos/genética , Animais , Proteínas de Transporte de Cátions/genética , Linhagem Celular , Membrana Celular/química , Membrana Celular/genética , Cricetulus , Concentração de Íons de Hidrogênio , Transporte de Íons/genética , Modelos Moleculares , Mutagênese Sítio-Dirigida , Mutação , Domínios Proteicos/genética , Trocador 1 de Sódio-Hidrogênio/química , Trocadores de Sódio-Hidrogênio/genética
11.
Biochim Biophys Acta Biomembr ; 1861(1): 191-200, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30071192

RESUMO

The mammalian Na+/H+ exchanger isoform 1 (NHE1) is an integral membrane protein that regulates intracellular pH (pHi) by removing a single intracellular proton in exchange for one extracellular sodium ion. It is involved in cardiac hypertrophy and ischemia reperfusion damage to the heart and elevation of its activity is a trigger for breast cancer metastasis. NHE1 has an extensive 500 amino acid N-terminal membrane domain that mediates transport and consists of 12 transmembrane segments connected by intracellular and extracellular loops. Intracellular loops are hypothesized to modulate the sensitivity to pHi. In this study, we characterized the structure and function of intracellular loop 5 (IL5), specifically amino acids 431-443. Mutation of eleven residues to alanine caused partial or nearly complete inhibition of transport; notably, mutation of residues L432, T433, I436, N437, R440 and K443 demonstrated these residues had critical roles in NHE1 function independent of effects on targeting or expression. The nuclear magnetic resonance (NMR) solution spectra of the IL5 peptide in a membrane mimetic sodium dodecyl sulfate solution revealed that IL5 has a stable three-dimensional structure with substantial alpha helical character. NMR chemical shifts indicated that K438 was in close proximity with W434. Overall, our results show that IL5 is a critical, intracellular loop with a propensity to form an alpha helix, and many residues of this intracellular loop are critical to proton sensing and ion transport.


Assuntos
Trocador 1 de Sódio-Hidrogênio/química , Trocadores de Sódio-Hidrogênio/química , Alanina/química , Animais , Membrana Celular/química , Citoplasma/química , Humanos , Concentração de Íons de Hidrogênio , Transporte de Íons , Espectroscopia de Ressonância Magnética , Mutagênese Sítio-Dirigida , Mutação , Peptídeos/química , Domínios Proteicos , Isoformas de Proteínas/química , Estrutura Secundária de Proteína , Prótons
12.
Int J Radiat Oncol Biol Phys ; 99(4): 1048-1049, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-29063839
13.
J Mol Cell Cardiol ; 99: 65-75, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27555478

RESUMO

The mammalian Na+/H+ exchanger isoform 1 (NHE1) is a ubiquitous plasma membrane protein that is a key regulator of intracellular pH in isolated cardiomyocytes. A 500 amino acid membrane domain removes protons and is regulated by a 315 amino acid cytosolic domain. In the myocardium, aberrant regulation of NHE1 contributes to ischemia reperfusion damage and to heart hypertrophy. We examined mechanisms of regulation of NHE1 in the myocardium by endothelin and ß-Raf. Endothelin stimulated NHE1 activity and activated Erk-dependent pathways. Inhibition of ß-Raf reduced NHE1 activity and Erk-pathway activation. We demonstrated that myocardial ß-Raf binds to the C-terminal 182 amino acids of the NHE1 protein and that ß-Raf is associated with NHE1 in intact cardiomyocytes. NHE1 was phosphorylated in vivo and the protein kinase inhibitor sorafenib reduced NHE1 phosphorylation levels. Immunoprecipitates of ß-Raf from cardiomyocytes phosphorylated the C-terminal 182 amino acids of NHE1 and mass spectrometry analysis showed that amino acid Thr653 was phosphorylated. Mutation of this amino acid to Ala resulted in defective activity while mutation to Asp restored the activity. The results demonstrate that Thr653 is an important regulatory amino acid of NHE1 that is activated through ß-Raf dependent pathways by phosphorylation either directly or indirectly by ß-Raf, and this affects NHE1 activity.


Assuntos
Proteínas Proto-Oncogênicas B-raf/metabolismo , Transdução de Sinais , Trocadores de Sódio-Hidrogênio/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , Membrana Celular/metabolismo , Concentração de Íons de Hidrogênio , Mutação , Miócitos Cardíacos/metabolismo , Fosforilação , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas/genética , Ratos , Trocadores de Sódio-Hidrogênio/química , Trocadores de Sódio-Hidrogênio/genética , Tironinas/genética , Tironinas/metabolismo
14.
Cell Physiol Biochem ; 37(2): 592-602, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26343984

RESUMO

BACKGROUND/AIMS: Benzene is a toxic chemical whose leukemogenic effects have been studied for decades. The mechanisms of benzene-induced toxicity and leukemogenicity are not fully understood, although the involvement of several pathways has been suggested, including oxidative stress, DNA damage, cell cycle regulation and programmed cell death. In the present study, we investigated the effect of hydroquinone (HQ), a major benzene metabolite, on the viability of bone marrow derived mesenchymal stem cells (BMSCs) and explored the underlying mechanisms. METHODS: First, we study the the effect of HQ on BMSCs cell viability, apoptosis and the expressions of MDR1 and NF-κB. Then we investigate the MDR1 on cell viability and cell apoptosis for BMSCs under HQ treatment. Finally, we studied the impact of nuclear factor κB (NF-κB) on the expression of MDR1. RESULTS: Our results showed that HQ decreased cell viability and promoted cell apoptosis of BMSCs, as determined by the MTT assay and flow cytometry. Western blotting and quantitative PCR showed that HQ downregulated the expression of the MDR1 gene by inhibiting the activation and nuclear translocation of the transcription factor NF-κB. Overexpression of MDR1 attenuated the inhibitory effect of HQ on cell viability in BMSC. CONCLUSION: The results of the present study suggest the involvement of the multidrug resistance membrane transporter MDR1 and the NF-κB pathway in the cytotoxicity of benzene and its metabolites. Further studies are necessary to clarify the role of the pathways involved and the crosstalk between them in mediating the effects of HQ in bone marrow progenitor cells.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Hidroquinonas/toxicidade , Células-Tronco Mesenquimais/efeitos dos fármacos , Animais , Apoptose , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica , Células-Tronco Mesenquimais/citologia , NF-kappa B/metabolismo , Coelhos , Transdução de Sinais
15.
Biochim Biophys Acta ; 1848(10 Pt A): 2385-93, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26215741

RESUMO

The mammalian Na+/H+ exchanger isoform 1 (NHE1) is a ubiquitously expressed integral membrane protein present in mammalian cells. It is made up of a hydrophobic 500 amino acid membrane domain that transports and removes protons from within cells, and a regulatory intracellular cytosolic domain made of approximately 315 amino acids. Determining the structure of NHE1 is critical for both an understanding of the Na+/H+ exchange mechanism of transport, and in the design of new improved inhibitors for use in treatment of several diseases in which it is involved. Differing models of the NHE1 protein have been proposed. The first model suggested by two groups proposes that amino acids 1-500 form a 12 transmembrane segment spanning region in which amino acids 1-127 form two transmembrane segments, and amino acids 315-411 form a single transmembrane segment with membrane associated segments. A second model based on the structure of the Escherichia coli Na+/H+ exchanger protein proposes an overall similar topology, but suggests amino acids 1-127 are removed as a signal sequence and are not present in the mature protein. It also suggests a different topology of amino acids 315-411 to form three transmembrane segments. We used cysteine scanning accessibility and examination of glycosylation of the mature protein to characterize the NHE1 protein. Our results demonstrate that the model of NHE1 is correct which suggests that amino acids 1-127 form two transmembrane segments that remain connected to the mature protein, and the segment between amino acids 315-411 is one transmembrane segment.


Assuntos
Modelos Químicos , Modelos Moleculares , Trocadores de Sódio-Hidrogênio/química , Trocadores de Sódio-Hidrogênio/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Células CHO , Cricetulus , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Ligação Proteica , Conformação Proteica , Trocadores de Sódio-Hidrogênio/ultraestrutura
16.
Oncol Lett ; 10(1): 273-276, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26171013

RESUMO

Osteosarcoma (OS) is an aggressive primary bone cancer that usually affects children and young adolescents. Previous studies have demonstrated the implications of a small sub-population of cancer stem cells on treatment failure and tumor recurrence. The present study analyzed the characteristic features of the stem-like cells within the human OS-55 cell line. It was identified that 2.3% of the OS-55 cells were cancer stem-like side population (SP) cells. Following treatment with verapamil, the population of SP cells was reduced to 0.7%. The sphere formation assay revealed that the OS cells were able to rapidly form tumor spheres (also known as sarcospheres). Immunofluorescence analysis identified that the OS-55 cells expressed the cluster of differentiation 44, octamer-binding transcription factor-3/4A and Nanog stem cell surface markers. The results of the present study suggest that, as with other tumors, OS also contains a sub-population of cancer stem-like cells, which may have important implications in cancer diagnosis and treatment.

17.
Hum Mol Genet ; 24(2): 463-70, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25205112

RESUMO

Lichtenstein-Knorr syndrome is an autosomal recessive condition that associates sensorineural hearing loss and cerebellar ataxia. Here, we report the first identification of a gene involved in Lichtenstein-Knorr syndrome. By using a combination of homozygosity mapping and whole-exome sequencing, we identified the homozygous p.Gly305Arg missense mutation in SLC9A1 that segregates with the disease in a large consanguineous family. Mutant glycine 305 is a highly conserved amino acid present in the eighth transmembrane segment of all metazoan orthologues of NHE1, the Na(+)/H(+) exchanger 1, encoded by SLC9A1. We demonstrate that the p.Gly305Arg mutation causes the near complete de-glycosylation, mis-targeting and loss of proton pumping activity of NHE1. The comparison of our family with the phenotypes of spontaneous and knockout Slc9a1 murine models demonstrates that the association between ataxia and hearing loss is caused by complete or near complete loss of function of NHE1 and altered regulation of pHi in the central nervous system.


Assuntos
Proteínas de Transporte de Cátions/genética , Ataxia Cerebelar/genética , Surdez/genética , Displasia Fibrosa Óssea/genética , Síndromes de Imunodeficiência/genética , Mutação de Sentido Incorreto , Neutropenia/genética , Trocadores de Sódio-Hidrogênio/genética , Animais , Proteínas de Transporte de Cátions/metabolismo , Ataxia Cerebelar/metabolismo , Surdez/metabolismo , Fácies , Feminino , Displasia Fibrosa Óssea/metabolismo , Humanos , Síndromes de Imunodeficiência/metabolismo , Masculino , Camundongos , Camundongos Knockout , Neutropenia/metabolismo , Trocador 1 de Sódio-Hidrogênio , Trocadores de Sódio-Hidrogênio/metabolismo
18.
Biochem Cell Biol ; 92(6): 541-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25350536

RESUMO

Na(+)/H(+) exchanger isoform 1 (NHE1) is the principal plasma membrane Na(+)/H(+) exchanger of mammalian cells and functions by exchanging one intracellular proton for one extracellular sodium ion. Critical transmembrane segments of Na(+)/H(+) exchangers have discontinuous transmembrane helices, which result in a dipole within the membrane. Amino acid R425 has been suggested to play an important role in neutralizing one such helix dipole. To investigate this hypothesis, R425 was mutated to alanine, glutamine, histidine, or lysine and the mutant NHE1 proteins were expressed and characterized in NHE1-deficient cells. The R425A and R425E mutants exhibited complete loss of expression of mature, fully glycosylated NHE1, reduced expression overall, and greatly reduced cell surface targeting. The cell surface targeting, expression, and activity of the R425H and R425K mutant proteins were also impaired, though residual NHE1 activity remained. When reduced targeting and expression were accounted for, the R425H and R425K mutant proteins had activity similar to that of the wild-type protein. The results suggest that R425 is critical for NHE1 expression, targeting, and activity and that replacement with another basic residue can rescue activity. The findings are consistent with a role for R425 in both neutralizing a helix dipole and maintaining NHE1 structure and function.


Assuntos
Proteínas de Transporte de Cátions/metabolismo , Regulação da Expressão Gênica/fisiologia , Mutação de Sentido Incorreto , Trocadores de Sódio-Hidrogênio/metabolismo , Substituição de Aminoácidos , Animais , Arginina/genética , Arginina/metabolismo , Proteínas de Transporte de Cátions/genética , Linhagem Celular Tumoral , Cricetinae , Humanos , Estrutura Secundária de Proteína , Transporte Proteico/fisiologia , Trocador 1 de Sódio-Hidrogênio , Trocadores de Sódio-Hidrogênio/genética , Relação Estrutura-Atividade
19.
J Occup Environ Med ; 56(10): e92-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25285841

RESUMO

OBJECTIVE: To evaluate the impact of exposure to low concentrations of benzene on the platelet-associated antibodies and platelet parameters. METHODS: We carried out an analysis on 121 benzene-exposed workers and 110 healthy workers whose blood samples were collected and the levels of platelet-associated antibodies and platelet parameters were assessed. Benzene emissions were monitored over 5 years. RESULTS: Large-platelet cell ratios (P-LCR), platelet distribution width (PDW), and mean platelet volume (MPV) were significantly higher in benzene-exposed participants than in control participants. In participants who smoke cigarettes or drank alcohol, P-LCR, PDW, and MPV were more significantly elevated in the benzene-exposed group than in nonsmokers and nondrinkers. Platelet-associated immunoglobulin (PAIg) levels in benzene-exposed participants were higher than those in the control group, and PAIgA and PAIgM levels correlated with cumulative benzene exposure. CONCLUSIONS: Exposure to low concentrations of benzene can induce changes in PAIg levels and platelet parameters.


Assuntos
Anticorpos/sangue , Antígenos de Plaquetas Humanas/sangue , Benzeno/toxicidade , Plaquetas/efeitos dos fármacos , Exposição Ocupacional/efeitos adversos , Adulto , China , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Inquéritos e Questionários
20.
Artigo em Chinês | MEDLINE | ID: mdl-25182814

RESUMO

OBJECTIVE: To explore the effects of acrylonitrile on T lymphocyte subsets, expression of toll-like receptor 4 and related cytokines in rats. METHODS: Sixty-four Sprague-Dawley rats were randomly divided into 4 female groups and 4 male groups, and there were 8 rats in each group. Rats in each group were respectively given a single dose of 0, 5, 10 and 20 mg/kg acrylonitrile by gavage, once a day, 5 days a week, for 13 weeks. Blood and spleen T lymphocyte subsets was detected by flow cytometry, the mRNA expression of TLR4, IL-1ß and TNF-α was analyzed by real-time quantitative PCR, the protein expression of TLR4 was evaluated by Western blot. RESULTS: Compared with control group, the percentages of blood CD3, CD4 T cells in 20 mg/kg female group and CD4/CD8 ratio in 5, 10 and 20 mg/kg female groups was significantly decreased, CD8 T cells in 20 mg/kg group was significantly increased (P < 0.05 or P < 0.01), blood CD3 T cells in 5 mg/kg male group, CD4 T cells and CD4/CD8 ratio in 20 mg/kg male groups were lower than that of control group, CD8 T cells in 20 mg/kg make group was significantly in oreased (P < 0.05 or P < 0.01). Spleen CD4, CD8 T lymphocyte percentages and CD4/CD8 ratio in 20 mg/kg female group decreased significantly, CD8 T cells in 20 mg/kg male group was significantly increased (P < 0.05 or P < 0.01), spleen CD3, CD4, CD8 T cells in 20 mg/kg male group and CD4/CD8 ratio in 10, 20 mg/kg male groups was also significantly decreased, CD3 T cells in 20 mg/kg and CD8 T cells in 10, 20 mg/kg male groups were significantly increased (P < 0.05 or P < 0.01) (TLR4 mRNA was lower expressed in 5, 10 and 20 mg/kg male groups and 10 mg/kg female group (P < 0.05 or P < 0.01), and TLR4 protein in 5 mg/kg female group and 20 mg/kg male group was significantly lower than control group (P < 0.05). The expression level of IL-1ß mRNA was significantly decreased in 5, 10 and 20 mg/kg female group and 5, 10 mg/kg male group (P < 0.05 or P < 0.01), TNF-α mRNA was lower expressed in 10, 20 mg/kg female groups and 5, 10 mg/kg male groups (P < 0.01). CONCLUSION: Acrylonitrile may lead to the changes of CD3, CD4, CD8 T lymphocyte percentages and CD4/CD8 ratio in rat blood and spleen, and also significantly effected the expression level of TLR4 mRNA and protein together with the secretion of IL-1ß, TNF-α. This may cause effects on the cellular immune function.


Assuntos
Acrilonitrila/toxicidade , Subpopulações de Linfócitos T/imunologia , Receptor 4 Toll-Like/metabolismo , Animais , Feminino , Interleucina-1beta/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Subpopulações de Linfócitos T/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
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