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1.
Nature ; 609(7929): 986-993, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36104568

RESUMO

Nutrients and energy have emerged as central modulators of developmental programmes in plants and animals1-3. The evolutionarily conserved target of rapamycin (TOR) kinase is a master integrator of nutrient and energy signalling that controls growth. Despite its key regulatory roles in translation, proliferation, metabolism and autophagy2-5, little is known about how TOR shapes developmental transitions and differentiation. Here we show that glucose-activated TOR kinase controls genome-wide histone H3 trimethylation at K27 (H3K27me3) in Arabidopsis thaliana, which regulates cell fate and development6-10. We identify FERTILIZATION-INDEPENDENT ENDOSPERM (FIE), an indispensable component of Polycomb repressive complex 2 (PRC2), which catalyses H3K27me3 (refs. 6-8,10-12), as a TOR target. Direct phosphorylation by TOR promotes the dynamic translocation of FIE from the cytoplasm to the nucleus. Mutation of the phosphorylation site on FIE abrogates the global H3K27me3 landscape, reprogrammes the transcriptome and disrupts organogenesis in plants. Moreover, glucose-TOR-FIE-PRC2 signalling modulates vernalization-induced floral transition. We propose that this signalling axis serves as a nutritional checkpoint leading to epigenetic silencing of key transcription factor genes that specify stem cell destiny in shoot and root meristems and control leaf, flower and silique patterning, branching and vegetative-to-reproduction transition. Our findings reveal a fundamental mechanism of nutrient signalling in direct epigenome reprogramming, with broad relevance for the developmental control of multicellular organisms.


Assuntos
Arabidopsis , Glucose , Alvo Mecanístico do Complexo 2 de Rapamicina , Fosfatidilinositol 3-Quinases , Desenvolvimento Vegetal , Complexo Repressor Polycomb 2 , Proteínas Repressoras , Transdução de Sinais , Arabidopsis/embriologia , Arabidopsis/enzimologia , Arabidopsis/genética , Arabidopsis/metabolismo , Diferenciação Celular/genética , Linhagem da Célula/genética , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Glucose/metabolismo , Histonas/química , Histonas/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Mutação , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Desenvolvimento Vegetal/genética , Complexo Repressor Polycomb 2/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fatores de Transcrição/genética
2.
Proc Natl Acad Sci U S A ; 120(21): e2304081120, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37186828

RESUMO

Chemotherapy typically destroys the tumor mass but rarely eradicates the cancer stem cells (CSCs) that can drive metastatic recurrence. A key current challenge is finding ways to eradicate CSCs and suppress their characteristics. Here, we report a prodrug, Nic-A, created by combining a carbonic anhydrase IX (CAIX) inhibitor, acetazolamide, with a signal transducer and transcriptional activator 3 (STAT3) inhibitor, niclosamide. Nic-A was designed to target triple-negative breast cancer (TNBC) CSCs and was found to inhibit both proliferating TNBC cells and CSCs via STAT3 dysregulation and suppression of CSC-like properties. Its use leads to a decrease in aldehyde dehydrogenase 1 activity, CD44high/CD24low stem-like subpopulations, and tumor spheroid-forming ability. TNBC xenograft tumors treated with Nic-A exhibited decreased angiogenesis and tumor growth, as well as decreased Ki-67 expression and increased apoptosis. In addition, distant metastases were suppressed in TNBC allografts derived from a CSC-enriched population. This study thus highlights a potential strategy for addressing CSC-based cancer recurrence.


Assuntos
Pró-Fármacos , Neoplasias de Mama Triplo Negativas , Humanos , Linhagem Celular Tumoral , Neoplasias de Mama Triplo Negativas/metabolismo , Niclosamida/farmacologia , Niclosamida/metabolismo , Niclosamida/uso terapêutico , Pró-Fármacos/uso terapêutico , Recidiva Local de Neoplasia/patologia , Fatores de Transcrição/metabolismo , Células-Tronco Neoplásicas/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Chem Soc Rev ; 52(13): 4488-4514, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37338931

RESUMO

One-dimensional (1-D) nanomaterials possess unique shape-dependent phyicochemical properties and are increasingly recognized as promising materials for nanotechnology. 1-D nanomaterials can be classified according to their shape, such as nanorods, nanotubes, nanowires, self-assembled nanochains, etc., and have been applied in electronics, photonics, and catalysis. The biological characteristics of 1-D nanomaterials, including high drug loading efficiency, prolonged blood circulation, the ability to capture cancer cells, unique cellular uptake mechanisms, efficient photothermal conversion, and material tunability, have aided in extending their potential to biomedical applications, particularly in cancer therapy and diagnosis. This review highlights a novel perspective on emerging 1-D nanomaterials for cancer therapy and diagnosis by introducing the definition of 1-D nanomaterials, their shape-dependent physicochemical properties, biomedical applications, and recent advances in cancer therapy and diagnosis. This review also proposes unexplored potential nanomaterial types and therapeutic applications for 1-D nanomaterials. In particular, the most significant and exciting advances in recent years, including ultrasound-enabled sonodynamic therapy, magnetic field-based therapy, and bioresponsive 1-D nanomaterials for intracellular self-assembly in situ, are discussed along with novel therapeutic concepts, such as piezoelectric 1-D nanomaterials, nanozyme-based nanomedicine, and others.


Assuntos
Nanoestruturas , Neoplasias , Nanoestruturas/uso terapêutico , Nanoestruturas/química , Nanotecnologia/métodos , Nanomedicina , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico
4.
Neuromodulation ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38752945

RESUMO

OBJECTIVES: We hypothesized that the duration of pulsed radiofrequency (PRF) application may affect the effectiveness of PRF in patients with chronic lumbosacral radicular pain (LRP). MATERIALS AND METHODS: In this prospective, double-blind, randomized study, 68 patients were randomly allocated to two groups: a 6-minute group, in which PRF was applied at 42 °C for 2 minutes followed by a 2-minute pause, repeated three times; and a 12-minute group, with a continuous application at 42 °C for 12 minutes. The total application time in each group was equal. After PRF, 2 to 3 mL of 1% lidocaine with 5 mg of dexamethasone was injected. The primary outcome was the intensity of leg pain measured using a numerical rating scale (NRS) three months after the procedure. The secondary outcomes were intensities of leg and back pain, the Oswestry Disability Index (ODI), the Medication Quantification Scale III (MQS), the Global Perceived Effect of Satisfaction (GPES), and the incidence of adverse events during follow-up. Primary and secondary outcomes were analyzed using a linear mixed-effect model in the modified intention-to-treat population. RESULTS: Each group comprised 34 patients. Three patients in each group did not receive the allocated intervention owing to alleviation of pain. The estimated NRS mean of leg pain at three months was 4.0 (95% CI, 3.2-4.9) and 4.5 (95% CI, 3.6-5.4) in the 6- and 12-minute groups, respectively, with no significant difference between groups (estimated mean difference, -0.5; 95% CI, -1.8 to 0.8; p = 0.436). Regarding the intensities of leg and back pain, ODI, MQS, and GPES, there was no significant difference between the two groups except for GPES at six months. No adverse events were observed in the groups. CONCLUSIONS: Among patients with chronic LRP, a prolonged PRF application of 12 minutes, compared with 6 minutes, caused no significant difference in leg pain intensity. CLINICAL TRIAL REGISTRATION: The Clinicaltrials.gov registration number under the Clinical Trial Registry of Korea for the study is KCT0003850; https://cris.nih.go.kr.

5.
Medicina (Kaunas) ; 60(6)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38929474

RESUMO

Background: Increasing evidence supporting the clinical effectiveness of cooled radiofrequency ablation (RFA) therapy for genicular nerves in patients with chronic knee osteoarthritis (OA) exists. However, no study has been conducted to eliminate the potential influence of a placebo effect associated with this procedure. Therefore, we evaluated the efficacy of cooled RFA compared with a sham procedure in patients with painful knees due to OA. Methods: In this double-blind, randomized, controlled study, participants were randomly assigned to receive cooled RFA of the knee (cooled RFA group, n = 20) or a sham procedure (sham group, n = 20). The primary outcome was the proportion of successful responders at the three-month follow-up. The secondary outcomes were successful responders at one and six months; pain intensity of the knee; functional status; medication; and satisfaction at one, three, and six months after the procedures. Results: For the primary outcome, the successful responder rate was significantly higher in the cooled RFA group (76.5%) than in the sham group (33.3%) (p = 0.018). For the secondary outcome, more successful responders were observed in the cooled RFA group than in the sham group at one and six months after the procedure (p = 0.041 and 0.007, respectively). The decreased knee pain intensity was maintained throughout the six-month follow-up period in the cooled RFA group. No differences were observed in functional status, medication change, or satisfaction in both groups. Conclusions: The cooled RFA of genicular nerves offers significant pain relief and surpasses the effects attributable to a placebo.


Assuntos
Osteoartrite do Joelho , Ablação por Radiofrequência , Humanos , Método Duplo-Cego , Osteoartrite do Joelho/terapia , Osteoartrite do Joelho/cirurgia , Osteoartrite do Joelho/complicações , Feminino , Masculino , Ablação por Radiofrequência/métodos , Pessoa de Meia-Idade , Idoso , Resultado do Tratamento , Dor Crônica/terapia , Dor Crônica/etiologia , Medição da Dor , Articulação do Joelho/inervação
6.
Medicina (Kaunas) ; 59(5)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37241078

RESUMO

Background and Objectives: With the aging population, the incidence of degenerative lumbar spinal stenosis (LSS) is increasing. Sarcopenia is an age-related muscular decrease. Although epidural balloon neuroplasty is effective in patients with LSS refractory to conventional treatments, its effect has not been assessed in patients with sarcopenia. Therefore, this study evaluated the effect of epidural balloon neuroplasty in patients with LSS and sarcopenia. Materials and Methods: This retrospective study reviewed the following details from the electronic medical records: patient characteristics, including sex, age, body mass index, diabetes, hypertension, stenosis grading, pain duration, location, pain intensity, and medications. Back and leg pain intensity was evaluated before and after the procedure at one, three, and six months during the follow-up period. A generalized estimating equations model was used at six months follow-up. Patients were divided into sarcopenia and non-sarcopenia groups using the cross-sectional area of the psoas muscle at the level of L3 on magnetic resonance imaging. Results: A total of 477 patients were included (sarcopenia group: 314 patients, 65.8%; non-sarcopenia group: 163 patients, 34.2%). Age, sex, body mass index, and medication quantification scale III were statistically different between both groups. The generalized estimating equations analyses-with unadjusted and adjusted estimation-revealed a significantly reduced pain intensity after the procedure compared to the baseline in both groups. The difference in pain intensity between both groups was not statistically different. Conclusions: Percutaneous epidural balloon neuroplasty may be considered for patients with chronic lumbar LSS regardless of accompanying sarcopenia.


Assuntos
Estenose Espinal , Humanos , Idoso , Estenose Espinal/complicações , Estenose Espinal/cirurgia , Estudos Retrospectivos , Vértebras Lombares/cirurgia , Vértebras Lombares/patologia , Catéteres , Constrição Patológica , Resultado do Tratamento
7.
Nucleic Acids Res ; 48(6): 3328-3342, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-32002546

RESUMO

Monoubiquitination of the Fanconi anemia complementation group D2 (FANCD2) protein by the FA core ubiquitin ligase complex is the central event in the FA pathway. FANCA and FANCG play major roles in the nuclear localization of the FA core complex. Mutations of these two genes are the most frequently observed genetic alterations in FA patients, and most point mutations in FANCA are clustered in the C-terminal domain (CTD). To understand the basis of the FA-associated FANCA mutations, we determined the cryo-electron microscopy (EM) structures of Xenopus laevis FANCA alone at 3.35 Å and 3.46 Å resolution and two distinct FANCA-FANCG complexes at 4.59 and 4.84 Å resolution, respectively. The FANCA CTD adopts an arc-shaped solenoid structure that forms a pseudo-symmetric dimer through its outer surface. FA- and cancer-associated point mutations are widely distributed over the CTD. The two different complex structures capture independent interactions of FANCG with either FANCA C-terminal HEAT repeats, or the N-terminal region. We show that mutations that disturb either of these two interactions prevent the nuclear localization of FANCA, thereby leading to an FA pathway defect. The structure provides insights into the function of FANCA CTD, and provides a framework for understanding FA- and cancer-associated mutations.


Assuntos
Proteína do Grupo de Complementação A da Anemia de Fanconi/ultraestrutura , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/ultraestrutura , Proteína do Grupo de Complementação G da Anemia de Fanconi/ultraestrutura , Anemia de Fanconi/genética , Animais , Núcleo Celular/genética , Núcleo Celular/ultraestrutura , Microscopia Crioeletrônica , Cristalografia por Raios X , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/ultraestrutura , Anemia de Fanconi/patologia , Proteína do Grupo de Complementação A da Anemia de Fanconi/genética , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/genética , Proteína do Grupo de Complementação G da Anemia de Fanconi/química , Humanos , Complexos Multiproteicos/química , Complexos Multiproteicos/genética , Mutação , Ligação Proteica/genética , Conformação Proteica , Xenopus laevis/genética
8.
Chem Soc Rev ; 50(4): 2260-2279, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33367452

RESUMO

Pnictogens (the non-metal phosphorus, metalloids arsenic and antimony, and metal bismuth) possess diverse chemical characteristics that support the formation of extended molecular structures. As witnessed by the centuries-old (and ongoing) clinical utilities, pnictogen-based compounds have secured their places in history as "magic bullet" therapeutic drugs in medicinal contexts. Moreover, with the development of recent metalloproteomics and bio-coordination chemistry, the pnictogen-based drugs functionally binding to proteins/enzymes in biological systems have been underlaid for "drug repurposing" with promising opportunities. Furthermore, advances in the modern materials science and nonotechnology have stimulated a revolution in other newly discovered forms of pnictogens-phosphorene, arsenene, antimonene, and bismuthine (layered pnictogens). Based on their favorable optoelectronic properties, layered pnictogens have shown dramatic superiority as emerging photonic nanomedicines for the treatment of various diseases. This tutorial review outlines the history and mechanism of action of ancient pnictogen-based drugs (e.g., arsenical compounds in traditional Chinese medicine) and their repurposing into modern therapeutics. Then, the revolutionary use of emerging layered pnictogens as photonic nanomedicines, alongside assessments of their in vivo biosafety, is discussed. Finally, the challenges to further development of pnictogens are set forth and insights for further exploration of their appealing properties are offered. This tutorial review may also provide some deep insights into the fields of integrated traditional Chinese and Western medicines from the perspective of materials science and nanotechnology.


Assuntos
Antimônio/química , Arsenicais/química , Bismuto/química , Nanoestruturas/química , Preparações Farmacêuticas/química , Compostos de Fósforo/química , Animais , Antimônio/farmacologia , Arsenicais/farmacologia , Materiais Biocompatíveis/química , Bismuto/farmacologia , Humanos , Imunoterapia , Estrutura Molecular , Nanomedicina , Dispositivos Ópticos , Compostos de Fósforo/farmacologia , Fototerapia , Ligação Proteica , Radioterapia
9.
Int J Med Sci ; 18(12): 2736-2742, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34104106

RESUMO

Background: Chronic lumbar radicular pain often accompanies neuropathic pain. The treatment may follow a screening for probable neuropathic pain rather than the definitive diagnosis, which is often difficult in daily practice. However, interventional management may have limited effects on symptoms in patients with neuropathic radicular pain refractory to conservative treatments. The purpose of this study is to evaluate the factors associated with successful responses after lumbar epidural intervention in patients with chronic lumbar neuropathic radicular pain determined by Douleur Neuropathique 4 (DN4). Methods: We retrospectively reviewed 221 chronic lumbar radicular pain patients using a DN4 questionnaire prior to the epidural interventional procedure. The patients were divided into two groups according to the DN4 questionnaire: <4-point DN4 and ≥4 DN4. The numerical rating scale (NRS) for pain intensity, changes in physical functional status, and the use of pain medication were obtained before and 1 month after the procedure. Successful responder was defined based on robust combination of outcome parameters. The factors associated with successful response were analyzed using univariate and multivariate regression. Results: We found 170 (76.9%) patients with DN4 <4 and 51 (23.1%) with a score ≥4. Among the total 221 patients, 129 (58.4%) were successful responders and 92 (41.6%) were non-responders regardless of DN4 score. We observed a significantly lower proportion of successful responders among patients with a DN4 score ≥4 (22, 43.1%) than patients with a score <4 (107, 62.9%) (P=0.012). After adjusting in multivariate regression analysis, the DN4 score was independently associated with response after lumbar epidural intervention (odds ratio [OR]=0.838; 95% confidence interval [CI]=0.718-0.978; P=0.025). In subgroup logistic regression analysis according to the DN4 score, adjuvant administration of hypertonic saline during epidural interventions in patients with a DN4 score ≥4 (OR=3.71; CI=1.142-12.457; P=0.029) was associated with the success of the lumbar epidural procedure at 1 month. Conclusion: The adjuvant use of hypertonic saline in lumbar epidural interventions may be effective at least 1 month after the intervention in patients with probable neuropathic lumbar radicular pain ≥4 using the DN4.


Assuntos
Dor Crônica/terapia , Dor Lombar/tratamento farmacológico , Bloqueio Nervoso/métodos , Neuralgia/terapia , Solução Salina Hipertônica/administração & dosagem , Idoso , Anestésicos Locais/administração & dosagem , Dor Crônica/diagnóstico , Feminino , Seguimentos , Humanos , Injeções Epidurais , Dor Lombar/diagnóstico , Vértebras Lombares , Masculino , Pessoa de Meia-Idade , Neuralgia/diagnóstico , Manejo da Dor/métodos , Medição da Dor/estatística & dados numéricos , Estudos Retrospectivos , Resultado do Tratamento
10.
Int J Med Sci ; 18(13): 2957-2963, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34220323

RESUMO

Background: The ganglion impar (ganglion of Walther) block has been used to manage coccygeal and perineal (perianal and genital) pain due to both benign and malignant causes. However, the factors associated with successful responses to ganglion impar block are unknown. Therefore, in the present study, we aimed to identify the independent factors associated with successful responses to ganglion impar block in patients with chronic pain in coccygeal and perineal regions. Methods: From January 2008 to December 2017, we performed a retrospective review of 106 patients who underwent ganglion impar block. Patients were considered successful responders if they reported a decrease of more than 50% or 4 points on the 11-point (0 = no pain and 10 = worst possible pain) numerical rating scale 1 month after the procedure, while others were considered non-responders. Logistic regression analysis was performed to identify factors independently associated with successful responses at 1 month after the procedure. Results: Multivariable logistic regression analysis showed that cancer-related causes were significantly associated with successful responses at 1 month after ganglion impar block (odds ratio = 2.60, 95% confidence interval = 1.05 to 6.43, P = 0.038). Conclusion: Ganglion impar block may be more effective in cancer-related pain than pain due to benign causes.


Assuntos
Dor do Câncer/terapia , Dor Crônica/terapia , Gânglios Simpáticos/efeitos dos fármacos , Bloqueio Nervoso/estatística & dados numéricos , Neuralgia/terapia , Adulto , Idoso , Anestésicos Locais/administração & dosagem , Dor do Câncer/diagnóstico , Dor Crônica/diagnóstico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Bloqueio Nervoso/métodos , Neuralgia/diagnóstico , Medição da Dor/estatística & dados numéricos , Períneo/inervação , Prognóstico , Estudos Retrospectivos , Região Sacrococcígea/inervação , Resultado do Tratamento
11.
Chem Soc Rev ; 49(11): 3244-3261, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32337527

RESUMO

Phototherapy, including photodynamic therapy and photothermal therapy, has the potential to treat several types of cancer. However, to be an effective anticancer treatment, it has to overcome limitations, such as low penetration depth, low target specificity, and resistance conferred by the local tumor microenvironment. As a non-invasive technique, low-intensity ultrasound has been widely used in clinical diagnosis as it exhibits deeper penetration into the body compared to light. Recently, sonodynamic therapy (SDT), a combination of low-intensity ultrasound with a chemotherapeutic agent (sonosensitizer), has been explored as a promising alternative for cancer therapy. As all known cancer treatments such as chemotherapy, photodynamic therapy, photothermal therapy, immunotherapy, and drug delivery have been advanced independently enough to complement others substantially, the combination of these therapeutic modalities with SDT is opportune. This review article highlights the recent advances in SDT in terms of sonosensitizers and their formulations and anticancer therapeutic efficacy. Also discussed is the potential of SDT in combination with other modalities to address unmet needs in precision medicine.


Assuntos
Antineoplásicos/química , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Animais , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Humanos , Nanopartículas/química , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Medicina de Precisão , Terapia por Ultrassom
12.
J Exp Bot ; 71(1): 63-72, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31504722

RESUMO

Plants exhibit remarkable regeneration capacity, ensuring developmental plasticity. In vitro tissue culture techniques are based on plant regeneration ability and facilitate production of new organs and even the whole plant from explants. Plant somatic cells can be reprogrammed to form a pluripotent cell mass called the callus. A portion of pluripotent callus cells gives rise to a fertile shoot via de novo shoot organogenesis (DNSO). Here, we reconstitute the shoot regeneration process with four phases, namely pluripotency acquisition, shoot promeristem formation, establishment of the confined shoot progenitor, and shoot outgrowth. Additionally, other biological processes, including cell cycle progression and reactive oxygen species metabolism, which further contribute to successful completion of DNSO, are also summarized. Overall, this study highlights recent advances in the molecular and cellular events involved in DNSO, as well as the regulatory mechanisms behind key steps of DNSO.


Assuntos
Ciclo Celular/fisiologia , Organogênese Vegetal/fisiologia , Brotos de Planta/fisiologia , Regeneração/fisiologia
13.
Nanotechnology ; 31(45): 455202, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-32325431

RESUMO

Irradiation of MoS2 field-effect transistors (FETs) fabricated on Si/SiO2 substrates with electron beams (e-beams) below 30 keV creates electron-hole pairs (EHP) in the SiO2, which increase the interface trap density (Nit ) and change the current path in the channel, resulting in performance changes. In situ measurements of the electrical characteristics of the FET performed using a nano-probe system mounted inside a scanning electron microscope show that e-beam irradiation enables both multilayer and monolayer MoS2 channels act as conductors. The e-beams mostly penetrate the channel owing to their large kinetic energy, while the EHPs formed in the SiO2 layer can contribute to the conductance by flowing into the MoS2 channel or inducing the gate bias effect. The analysis of the device parameters in the initial state and the vent-evacuation state after e-beam irradiation can clarify the effect of the interplay between the e-beam-induced EHPs and ambient adsorbates on the carrier behavior, which depends on the thickness of the MoS2 layer. DC and low frequency noise analysis reveals that the e-beam-induced EHPs increase Nit from 109-1010 to 1011 cm-2 eV-1 in both monolayer and multilayer devices, while the interfacial Coulomb scattering parameter αSC increases by three times in the monolayer and decreases to one-tenth of its original value in the multilayer. In other words, an MoS2 layer with a thickness of ∼30 nm is less sensitive to adsorbates by surface screening. Thus, the carrier mobility in the monolayer device decreases from 45.7 to 40 cm2 V-1 s-1, while in the 30 nm-thick multilayer device, it increases from 4.9 to 5.6 cm2 V-1 s-1. This is further evidenced by simulations of the distribution of interface traps and channel carriers in the MoS2 FET before and after e-beam irradiation, demonstrating that Coulomb scattering decreases as the effective channel moves away from the interface.

14.
Pain Med ; 21(4): 677-685, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31529074

RESUMO

BACKGROUND: Contrast dispersion pattern on epidurography may be associated with clinical improvement after epidural neuroplasty. However, insufficient evidence supports this theory. The current study aims to evaluate the relevance of contrast dispersion and clinical improvement after percutaneous epidural neuroplasty using an inflatable balloon catheter. METHODS: One hundred patients with lumbar spinal stenosis who underwent combined balloon decompression and epidural adhesiolysis between March 2015 to December 2015 participated in the present study. Participants were divided into two groups by contrast dispersion pattern on postprocedural epidurography: the complete contrast dispersion (CCD) and incomplete contrast dispersion (ICCD) groups. The numeric rating scale (NRS), Oswestry Disability Index (ODI), and global perceived effects (GPE) were each assessed before and one, three, six, nine, and 12 months after the intervention. RESULTS: After combined balloon decompression and adhesiolysis, significant pain reduction and functional improvement were maintained up to 12 months in patients with lumbar spinal stenosis. NRS and GPE in the CCD group were significantly lower than in the ICCD group from six to 12 months after the intervention. The ODI in the CCD group was also significantly lower compared with that in the ICCD group from one to 12 months after the intervention. CONCLUSIONS: Combined balloon decompression and adhesiolysis with the inflatable balloon catheter can provide noteworthy pain reduction and improvement of physical function for a long-term period in patients with lumbar spinal stenosis. Because CCD showed better clinical improvement compared with ICCD, a contrast dispersion pattern may be associated with an improved clinical outcome.


Assuntos
Descompressão Cirúrgica/métodos , Dilatação/métodos , Espaço Epidural/diagnóstico por imagem , Vértebras Lombares , Estenose Espinal/cirurgia , Aderências Teciduais/cirurgia , Atividades Cotidianas , Idoso , Meios de Contraste , Feminino , Fluoroscopia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Medição da Dor , Estudos Prospectivos , Estenose Espinal/diagnóstico por imagem , Estenose Espinal/fisiopatologia , Aderências Teciduais/diagnóstico por imagem , Aderências Teciduais/fisiopatologia , Resultado do Tratamento
15.
Angew Chem Int Ed Engl ; 59(22): 8435-8439, 2020 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-32052897

RESUMO

Heteroatom-containing spiropolymers were constructed in a facile manner by a catalyst-free multicomponent spiropolymerization route. P1a2b as the most potent of these spiropolymers, demonstrates cluster-triggered emission resulting from strong interactions with the MDM2 protein. By preventing the anti-apoptotic p53/MDM2 interaction, P1a2b triggers apoptosis in cancerous cells, while demonstrating a good biocompatibility and non-toxicity in non-cancerous cells. The combined results from solution and cell-based cluster-triggered emission studies, docking, protein expression experiments and cytotoxicity data strongly support the MDM2-binding hypothesis and indicate a potential application as a fluorescent cancer marker as well as therapeutic for this spiropolymer.


Assuntos
Apoptose/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Compostos de Espiro/química , Compostos de Espiro/farmacologia , Linhagem Celular Tumoral , Humanos , Medicina de Precisão , Proteína Supressora de Tumor p53/metabolismo
16.
Plant J ; 93(6): 977-991, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29356153

RESUMO

Kinetochore, a protein super-complex on the centromere of chromosomes, mediates chromosome segregation during cell division by providing attachment sites for spindle microtubules. The NDC80 complex, composed of four proteins, NDC80, NUF2, SPC24 and SPC25, is localized at the outer kinetochore and connects spindle fibers to the kinetochore. Although it is conserved across species, functional studies of this complex are rare in Arabidopsis. Here, we characterize a recessive mutant, meristem unstructured-1 (mun-1), exhibiting an abnormal phenotype with unstructured shoot apical meristem caused by ectopic expression of the WUSCHEL gene in unexpected tissues. mun-1 is a weak allele because of the insertion of T-DNA in the promoter region of the SPC24 homolog. The mutant exhibits stunted growth, embryo arrest, DNA aneuploidy, and defects in chromosome segregation with a low cell division rate. Null mutants of MUN from TALEN and CRISPR/Cas9-mediated mutagenesis showed zygotic embryonic lethality similar to nuf2-1; however, the null mutations were fully transmissible via pollen and ovules. Interactions among the components of the NDC80 complex were confirmed in a yeast two-hybrid assay and in planta co-immunoprecipitation. MUN is co-localized at the centromere with HTR12/CENH3, which is a centromere-specific histone variant, but MUN is not required to recruit HTR12/CENH3 to the kinetochore. Our results support that MUN is a functional homolog of SPC24 in Arabidopsis, which is required for proper cell division. In addition, we report the ectopic generations of stem cell niches by the malfunction of kinetochore components.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Meristema/genética , Proteínas Associadas aos Microtúbulos/genética , Sementes/genética , Sequência de Aminoácidos , Arabidopsis/citologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Divisão Celular/genética , Segregação de Cromossomos , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Microscopia Confocal , Proteínas Associadas aos Microtúbulos/metabolismo , Mutação , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Homologia de Sequência de Aminoácidos
17.
Chem Soc Rev ; 47(7): 2280-2297, 2018 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-29528360

RESUMO

Over the last decade, organic photothermal therapy (PTT) agents have attracted increasing attention as a potential complement for, or alternative to, classical drugs and sensitizers involving inorganic nanomaterials. In this tutorial review, we provide a structured description of the main classes of organic photothermal agents and their characteristics. Representative agents that have been studied in the context of photothermal therapy since 2000 are summarized and recent advances in using PTT agents to address various cancers indications are highlighted.


Assuntos
Antineoplásicos/química , Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Fototerapia , Temperatura , Humanos , Processos Fotoquímicos
18.
Angew Chem Int Ed Engl ; 58(17): 5648-5652, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30809896

RESUMO

The aggregation of amyloid beta (Aß) proteins in senile plaques is a critical event during the development of Alzheimer's disease, and the postmortem detection of Aß-rich proteinaceous deposits through fluorescent staining remains one of the most robust diagnostic tools. In animal models, fluorescence imaging can be employed to follow the progression of the disease, and among the different imaging methods, two-photon microscopy (TPM) has emerged as one of the most powerful. To date, several near-infrared-emissive two-photon dyes with a high affinity for Aß fibrils have been developed, but there has often been a tradeoff between excellent two-photon cross-sections and large fluorescence signal-to-background ratios. In the current work, we introduced a twisted intramolecular charge state (TICT)-based de-excitation pathway, which results in a remarkable fluorescence increase of around 167-fold in the presence of Aß fibrils, while maintaining an excellent two-photon cross section, thereby enabling high-contrast ex vivo and in vivo TPM imaging. Overall, the results suggest that adopting TICT de-excitation in two-photon fluorophores may represent a general method to overcome the tradeoff between probe brightness and signal-to-background ratio.


Assuntos
Corantes Fluorescentes/metabolismo , Imagem Óptica/métodos , Placa Amiloide/metabolismo , Humanos
19.
Bioconjug Chem ; 29(4): 1446-1453, 2018 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-29570268

RESUMO

Realizing the significant roles of vicinal-dithiol proteins (VDPs) in maintaining the cellular redox homeostasis and their implication in many diseases, we synthesized a smart arsenate based fluorescent probe 1 which can preferentially target the mitochondrial membrane-bound vicinal dithiol proteins (VDPs), especially voltage-dependent anion channel (VDAC2). The probe targetability was demonstrated by in vitro studies such as colocalization, stimulated emission depletion (STED) super-resolution imaging, proteomic MS/MS analysis, and Western blot analysis. The probe represents a rare example of fluorescence labeling of mitochondrial membrane-bound VDPs and can provide a new way to construct VDPs-specific fluorescent probes to gain deeper understanding of their roles in mitochondrial-related disorders.


Assuntos
Arseniatos/química , Corantes Fluorescentes/química , Proteínas de Transporte da Membrana Mitocondrial/análise , Membranas Mitocondriais/química , Compostos de Sulfidrila/análise , Células HeLa , Humanos , Microscopia de Fluorescência/métodos , Membranas Mitocondriais/ultraestrutura , Imagem Óptica/métodos , Oxirredução , Canal de Ânion 2 Dependente de Voltagem/análise
20.
J Obstet Gynaecol Res ; 43(1): 211-219, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27862677

RESUMO

AIM: In the treatment of cervical cancer, the extent of lymphadenectomy is a matter of debate. The goal of the current study was to examine the question of whether the number of retrieved lymph nodes (RLN) can influence survival of patients with early stage cervical cancer. METHODS: The medical records of 180 FIGO stage IB-IIA cervical cancer patients treated with primary radical surgery were reviewed. Patients were divided into two groups: those with ≤ 40 RLN and those with > 40 RLN. Patients were also assigned to either the bulky (tumor size > 4 cm) cervical cancer group or the non-bulky (tumor size ≤ 4 cm) cervical cancer group. RESULTS: The number of RLN had a statistically significant effect on both disease-free survival (P = 0.04) and overall survival (P = 0.02) of all patients. Patients with > 40 RLN had better prognoses than those with ≤ 40 RLN. In the bulky cervical cancer group, the number of RLN was an independent prognostic factor. In multivariate analysis for the bulky cervical cancer group, > 40 RLN had a significant positive effect on disease-free survival (adjusted hazard ratio, 0.36; 95% confidence interval, 0.13-0.97) and overall survival (adjusted hazard ratio, 0.23; 95% confidence interval, 0.06-0.90). However, number of RLN was not an independent prognostic factor in the non-bulky cervical cancer group. CONCLUSIONS: A more extensive lymphadenectomy increased the survival of bulky cervical cancer patients. This finding may be helpful in determining surgical extent before surgery for cervical cancer.


Assuntos
Excisão de Linfonodo , Linfonodos/patologia , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/cirurgia , Adulto , Intervalo Livre de Doença , Feminino , Humanos , Linfonodos/cirurgia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fatores de Risco , Resultado do Tratamento , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/patologia
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