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1.
Development ; 151(5)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38345298

RESUMO

Although fluctuations in transcription factor (TF) dosage are often well tolerated, TF dosage modulation can change the target gene expression dynamics and result in significant non-lethal developmental phenotypes. Using MS2/MCP-mediated quantitative live imaging in early Drosophila embryos, we analyzed how changing levels of the gap gene Krüppel (Kr) affects transcriptional dynamics of the pair-rule gene even-skipped (eve). Halving the Kr dosage leads to a transient posterior expansion of the eve stripe 2 and an anterior shift of stripe 5. Surprisingly, the most significant changes are observed in eve stripes 3 and 4, the enhancers of which do not contain Kr-binding sites. In Kr heterozygous embryos, both stripes 3 and 4 display narrower widths, anteriorly shifted boundaries and reduced mRNA production levels. We show that Kr dosage indirectly affects stripe 3 and 4 dynamics by modulating other gap gene dynamics. We quantitatively correlate moderate body segment phenotypes of Kr heterozygotes with spatiotemporal changes in eve expression. Our results indicate that nonlinear relationships between TF dosage and phenotypes underlie direct TF-DNA and indirect TF-TF interactions.


Assuntos
Proteínas de Drosophila , Proteínas de Homeodomínio , Fatores de Transcrição Kruppel-Like , Animais , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo
2.
PLoS Pathog ; 19(12): e1011891, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38109416

RESUMO

Trichomonas vaginalis is a prevalent causative agent that causes trichomoniasis leading to uropathogenic inflammation in the host. The crucial role of the actin cytoskeleton in T. vaginalis cytoadherence has been established but the associated signaling has not been fully elucidated. The present study revealed that the T. vaginalis second messenger PIP2 is located in the recurrent flagellum of the less adherent isolate and is more abundant around the cell membrane of the adherent isolates. The T. vaginalis phosphatidylinositol-4-phosphate 5-kinase (TvPI4P5K) with conserved activity phosphorylating PI(4)P to PI(4, 5)P2 was highly expressed in the adherent isolate and partially colocalized with PIP2 on the plasma membrane but with discrete punctate signals in the cytoplasm. Plasma membrane PIP2 degradation by phospholipase C (PLC)-dependent pathway concomitant with increasing intracellular calcium during flagellate-amoeboid morphogenesis. This could be inhibited by Edelfosine or BAPTA simultaneously repressing parasite actin assembly, morphogenesis, and cytoadherence with inhibitory effects similar to the iron-depleted parasite, supporting the significance of PIP2 and iron in T. vaginalis colonization. Intriguingly, iron is required for the optimal expression and cell membrane trafficking of TvPI4P5K for in situ PIP2 production, which was diminished in the iron-depleted parasites. TvPI4P5K-mediated PIP2 signaling may coordinate with iron to modulate T. vaginalis contact-dependent cytolysis to influence host cell viability. These observations provide novel insights into T. vaginalis cytopathogenesis during the host-parasite interaction.


Assuntos
Parasitos , Trichomonas vaginalis , Animais , Cálcio/metabolismo , Citoesqueleto de Actina , Ferro/metabolismo
3.
Front Endocrinol (Lausanne) ; 13: 969149, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36051389

RESUMO

Objectives: Diabetic peripheral neuropathic pain (DPNP) is a prevalent chronic complication in patients with diabetes. Using a questionnaire is helpful for DPNP screening in outpatients. In this retrospective cohort, we aimed to examine whether DPNP diagnosed based on scoring questionnaires could predict long-term mortality in outpatients with type 2 diabetes. Methods: We enrolled 2318 patients who had joined the diabetes pay-for-performance program and completed the annual assessments, including both the identification pain questionnaire (ID pain) and Douleur Neuropathique en 4 questionnaire (DN4), between January 2013 and October 2013. Information on registered deaths was collected up to August 2019. Results: There was high consistency in the scores between the ID pain and DN4 (r = 0.935, P < 0.001). During the median follow-up of 6.2 years (interquartile range: 5.9-6.4 years), 312 patients deceased. Patients with an ID pain score of ≥ 2 had a higher mortality risk than those with a score of < 2 (hazard ratio [HR] = 1.394, 95%CI: 1.090-1.782), and patients with a DN4 score of ≥ 4 had a higher mortality risk than those with a score of < 4 (HR = 1.668, 95% confidence interval [CI]: 1.211-2.297). Patients consistently diagnosed with DPNP by the ID pain and DN4 had a significantly higher mortality risk (HR = 1.713, 95% CI: 1.223-2.398, P = 0.002), but not those discrepantly diagnosed with DPNP (P = 0.107), as compared with those without DPNP. Conclusions: Both the ID pain and DN4 for DPNP screening were predictive of long-term mortality in patients with type 2 diabetes. However, a discrepancy in the diagnosis of DPNP weakened the power of mortality prediction.


Assuntos
Diabetes Mellitus Tipo 2 , Neuropatias Diabéticas , Neuralgia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Neuropatias Diabéticas/complicações , Neuropatias Diabéticas/etiologia , Humanos , Neuralgia/complicações , Neuralgia/etiologia , Reembolso de Incentivo , Estudos Retrospectivos
4.
Front Plant Sci ; 12: 690064, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34434202

RESUMO

The manganese (Mn) tracking factor for mitochondrial Mn superoxide dismutase (MnSOD) has been annotated as yMTM1 in yeast, which belongs to the mitochondrial carrier family. We confirmed that Arabidopsis AtMTM1 and AtMTM2 are functional homologs of yMTM1 as they can revive yeast MnSOD activity in yMTM1-mutant cells. Transient expression of AtMnSOD-3xFLAG in the AtMTM1 and AtMTM2-double mutant protoplasts confirmed that AtMTM1 and AtMTM2 are required for AtMnSOD activation. Our study revealed that AtMnSOD interacts with AtMTM1 and AtMTM2 in the mitochondria. The expression levels of AtMTM1, AtMTM2, and AtMnSOD respond positively to methyl viologen (MV) and metal stress. AtMTM1 and AtMTM2 are involved in Mn and Fe homeostasis, root length, and flowering time. Transient expression of chloroplast-destined AtMnSOD revealed that an evolutionarily conserved activation mechanism, like the chloroplastic-localized MnSOD in some algae, still exists in Arabidopsis chloroplasts. This study strengthens the proposition that AtMTM1 and AtMTM2 participate in the AtMnSOD activation and ion homeostasis.

5.
Trauma Case Rep ; 34: 100496, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34195339

RESUMO

CASE: A 45-year-old woman sustained a unique lateral tibia plateau fracture pattern with a vertically rotated fragment composed of an intact articular surface and subchondral bone. During open reduction and internal fixation (ORIF), a full thickness radial tear of the lateral meniscus was found, which was repaired under direct visualization through arthrotomy. At final follow-up, the patient regained pain-free activity with good meniscus healing, as confirmed with a second-look arthroscopic examination. CONCLUSION: This case represents an undescribed fracture pattern that indicates an associated meniscus injury. A thorough evaluation, including Magnetic Resonance Imaging should be considered. One-stage ORIF followed with meniscus repair represents a good treatment option.

6.
Injury ; 52(6): 1556-1562, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33243524

RESUMO

OBJECTIVE: To compare the complications of patella fracture after open reduction and internal fixation using our innovative, loop-based modification of the tension band wiring technique and the traditional tension band wiring technique. METHODS: Fifty-eight patients with patella fracture (AO/OTA: 34-C) were enrolled in this retrospective case-control study during the study period. We treated 36 patients with the traditional tension band wiring and 22 patients with our loop anchor tension band technique. Lysholm knee scoring scale, sex, numbers of wire dislodge, number of implants removal between two groups were compared. RESULTS: The number of cases of wire dislodgement was zero in the loop anchor tension band group and seven in the traditional tension band group. There was statistically significant difference (P = 0.037). Lysholm knee score (P = 0.685) and operation time (P = 0.395) were not significantly different between the two groups CONCLUSIONS: The loop anchor tension band technique is safe and effective for treating patella fractures. The rates of implant loosening and wire pull-out were significantly lower in the loop anchor tension band group than those in the traditional technique group.


Assuntos
Fraturas Ósseas , Patela , Fios Ortopédicos , Estudos de Casos e Controles , Fixação Interna de Fraturas , Fraturas Ósseas/cirurgia , Humanos , Patela/cirurgia , Estudos Retrospectivos
7.
Comput Intell Neurosci ; 2017: 5739301, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29403528

RESUMO

Eye movement can be regarded as a pivotal real-time input medium for human-computer communication, which is especially important for people with physical disability. In order to improve the reliability, mobility, and usability of eye tracking technique in user-computer dialogue, a novel eye control system with integrating both mouse and keyboard functions is proposed in this paper. The proposed system focuses on providing a simple and convenient interactive mode by only using user's eye. The usage flow of the proposed system is designed to perfectly follow human natural habits. Additionally, a magnifier module is proposed to allow the accurate operation. In the experiment, two interactive tasks with different difficulty (searching article and browsing multimedia web) were done to compare the proposed eye control tool with an existing system. The Technology Acceptance Model (TAM) measures are used to evaluate the perceived effectiveness of our system. It is demonstrated that the proposed system is very effective with regard to usability and interface design.


Assuntos
Atenção/fisiologia , Medições dos Movimentos Oculares/instrumentação , Movimentos Oculares , Interface Usuário-Computador , Adolescente , Adulto , Interfaces Cérebro-Computador , Simulação por Computador , Feminino , Humanos , Masculino , Software , Inquéritos e Questionários , Carga de Trabalho , Adulto Jovem
8.
Invest New Drugs ; 31(4): 823-32, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23238608

RESUMO

Due to the development of drug resistance, the outcome for the majority of patients with acute myeloid leukemia (acute myelogenous leukemia; AML) remains poor. To prevent drug resistance and increase the therapeutic efficacy of treating AML, the development of new combinatory drug therapies is necessary. Sonic hedgehog (Shh) is expressed in AML biopsies and is essential for the drug resistance of cancer stem cells of AML. AML patients are frequently infected by bacteria and exposed to lipopolysaccharide (LPS). LPS itself, its derivatives, and its downstream effectors, such as tumor necrosis factor-α (TNF-α) and interferons (IFNs), have been shown to provoke anti-tumor effects. The application of a Shh inhibitor against AML cells in the presence of LPS/TNF-α/IFNs has not been investigated. We found that the Shh inhibitor cyclopamine in combination with LPS treatment synergistically induced massive cell apoptosis in THP-1 and U937 cells. The cytotoxic effects of this combined drug treatment were confirmed in 5 additional AML cell lines, in primary AML cells, and in an AML mouse model. Replacing cyclopamine with another Shh inhibitor, Sant-1, had the same effect. LPS could be substituted by TNF-α or IFNs to induce AML cell death in combination with cyclopamine. Our results suggest a potential strategy for the development of new therapies employing Shh antagonists in the presence of LPS/TNF-α/IFNs for the treatment of AML patients.


Assuntos
Proteínas Hedgehog/antagonistas & inibidores , Interferons/farmacologia , Leucemia Mieloide Aguda/patologia , Lipopolissacarídeos/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Animais , Contagem de Células , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Proteínas Hedgehog/metabolismo , Humanos , Camundongos , Camundongos SCID , Piperazinas/farmacologia , Pirazóis/farmacologia , Alcaloides de Veratrum/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Colloid Interface Sci ; 343(1): 7-17, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20022020

RESUMO

We demonstrate a simple method to synthesize silver wires by thermal reduction of aqueous AgNO(3) droplet with catalytic anatase TiO(2) nanoparticles which were spin-coated on Si wafer. Structural characterization of the silver wires shows that the nanowires grow primarily along the [011] direction. SEM image of the silver wires clearly shows the catalytic TiO(2) nano-cluster attached to the end of the each silver wire. Since the process was surfactant-free, the silver nanowires prepared by our method retain the excellent electrical conductivity. The intrinsic resistivity calculated from the current-voltage curve for a wire with 12880.41 nm(2) cross-section area was 18.72 microohm cm, which is about 11.6 times higher than that of bulk silver (1.61 microohm cm). Our simple method can be also applied to generate CuO with ring-shaped microstructure by using ITO conducting glass as matrix. We have found that the size and reproducibility are well-controllable. A single phase of CuO ring-shaped microstructure with outer diameters ranging from approximately 13 to 17 microm and inner diameters ranging from approximately 1.4 to 3.3 microm was obtained. The composition of CuO microring was confirmed by thin-film XRD and XPS analyses.

10.
Exp Hematol ; 36(2): 140-8, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18206725

RESUMO

OBJECTIVE: 2-Methoxyestradiol (2ME2) has been shown to induce apoptosis in leukemic cells, but its exact mechanism remains unclear. Because c-Myc plays a critical role in leukemogenesis, we evaluated whether 2ME2 acts on acute myeloid leukemia (AML) through modulation of c-Myc activity. MATERIALS AND METHODS: AML cell lines and primary AML leukemia were treated with 2ME2 and the relationship between 2ME2-induced apoptosis and changes in c-Myc activity was examined. RESULTS: 2ME2 induced mitochondrial apoptosis of human AML cells through increased reactive oxygen species. Further investigation showed that 2ME2 downregulated c-Myc expression in a time-dependent manner. Increased oxidative stress led to downregulation of c-Myc mRNA and protein, but did not affect the stability of c-Myc protein. To demonstrate the role of c-Myc in 2ME2-induced apoptosis, we ectopically expressed wild-type c-Myc in AML cells and found that ectopic expression of c-Myc abrogated the 2ME2-induced apoptosis. In addition, we showed that 2ME2 treatment inhibited phosphorylation of Akt and binding of nuclear factor-kappaB p65/p50 heterodimers to its DNA targets. As with results from cell lines studied, 2ME2 also induced cytotoxicity to primary AML cells and downregulated their c-Myc expression and induced apoptosis. CONCLUSION: Downregulation of c-Myc is critical for 2ME2-induced oxidative stress and apoptosis in AML cells. Our results might be extended to other types of cancers overexpressing c-Myc.


Assuntos
Apoptose/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Estradiol/análogos & derivados , Leucemia Mieloide Aguda/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Moduladores de Tubulina/farmacologia , 2-Metoxiestradiol , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Estradiol/farmacologia , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Mitocôndrias/genética , Mitocôndrias/metabolismo , Subunidade p50 de NF-kappa B/genética , Subunidade p50 de NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Células U937
11.
Leuk Res ; 31(10): 1403-11, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17445886

RESUMO

Valproic acid (VPA), an agent used for neurological disorders, has been shown to be a novel class of histone deacetylase inhibitor (HDACI), able to induce apoptosis and myeloid differentiation of acute myeloid leukemia (AML). In this study, we examined the underlying mechanisms in VPA-mediated activities in AML cells. VPA not only inhibited the growth of HL-60, U937 and NB4 cells by causing cell-cycle arrest at G(0)/G(1) phase and apoptosis, but also induced morphologic and phenotypic changes. VPA markedly increased p21WAF1, and downregulated c-Myc expression at transcriptional levels. Ectopic expression of wildtype c-Myc and T58A mutant significantly inhibited VPA-mediated growth inhibition. As with results from cell line studies, VPA also downregulated c-Myc levels, and induced apoptosis and myeloid differentiation of primary AML cells, leading to decreased colony-forming ability. Given the role of c-Myc in leukemogenesis, our study suggests that VPA might be a potential therapeutic agent for AML.


Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Genes myc/efeitos dos fármacos , Leucemia Mieloide/metabolismo , Ácido Valproico/farmacologia , Doença Aguda , Apoptose/efeitos dos fármacos , Western Blotting , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Expressão Gênica/efeitos dos fármacos , Humanos , Leucemia Mieloide/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
Exp Hematol ; 34(11): 1480-9, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17046567

RESUMO

OBJECTIVE: The protooncogene c-Myc plays an important role in the control of cell proliferation, apoptosis, and differentiation, and its aberrant expression is frequently seen in multiple human cancers, including acute myeloid leukemia (AML). As c-Myc heterodimerizes with Max to transactivate downstream target genes in leukemogenesis. Inhibition of the c-Myc/Max heterodimerization by the recently identified small-molecule compound, 10058-F4, might be a novel antileukemic strategy. MATERIALS AND METHODS: HL-60, U937, and NB4 cells and primary AML cells were used to examine the effects of 10058-F4 on apoptosis and myeloid differentiation. RESULTS: We showed that 10058-F4 arrested AML cells at G0/G1 phase, downregulated c-Myc expression and upregulated CDK inhibitors, p21 and p27. Meanwhile, 10058-F4 induced apoptosis through activation of mitochondrial pathway shown by downregulation of Bcl-2, upregulation of Bax, release of cytoplasmic cytochrome C, and cleavage of caspase 3, 7, and 9. Furthermore, 10058-F4 also induced myeloid differentiation, possibly through activation of multiple transcription factors. Similarly, 10058-F4-induced apoptosis and differentiation could also be observed in primary AML cells. CONCLUSION: Our study has shown that inhibition of c-Myc/Max dimerization with small-molecule inhibitors affects multiple cellular activities in AML cells and represents a potential antileukemic approach.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Leucemia Mieloide/metabolismo , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Tiazóis/farmacologia , Doença Aguda , Fatores de Transcrição de Zíper de Leucina Básica/antagonistas & inibidores , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Dimerização , Regulação para Baixo/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Fase G1/efeitos dos fármacos , Células HL-60 , Humanos , Leucemia Mieloide/tratamento farmacológico , Células Mieloides/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Relação Estrutura-Atividade , Células U937 , Regulação para Cima/efeitos dos fármacos
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