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1.
Cell ; 186(17): 3526-3528, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37595562

RESUMO

The development of molecular couriers to selectively package, export, and recover RNA molecules within human cells is a significant challenge. In this issue of Cell, Horns et al.1 introduce cellular RNA exporters, termed COURIERs, that package, secrete, and protect RNA cargo and establish the foundation for sophisticated cell-to-cell RNA communication.


Assuntos
Células Artificiais , Comunicação Celular , RNA , Animais , Humanos
2.
Bioorg Med Chem ; 100: 117588, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38295487

RESUMO

Microsatellite instability (MSI) is a hypermutable condition caused by DNA mismatch repair system defects, contributing to the development of various cancer types. Recent research has identified Werner syndrome ATP-dependent helicase (WRN) as a promising synthetic lethal target for MSI cancers. Herein, we report the first discovery of thiophen-2-ylmethylene bis-dimedone derivatives as novel WRN inhibitors for MSI cancer therapy. Initial computational analysis and biological evaluation identified a new scaffold for a WRN inhibitor. Subsequent SAR study led to the discovery of a highly potent WRN inhibitor. Furthermore, we demonstrated that the optimal compound induced DNA damage and apoptotic cell death in MSI cancer cells by inhibiting WRN. This study provides a new pharmacophore for WRN inhibitors, emphasizing their therapeutic potential for MSI cancers.


Assuntos
Instabilidade de Microssatélites , Neoplasias , Tiofenos , Humanos , Cicloexanonas , Neoplasias/tratamento farmacológico , Neoplasias/genética , Helicase da Síndrome de Werner/antagonistas & inibidores , Helicase da Síndrome de Werner/metabolismo , Tiofenos/química , Tiofenos/farmacologia
3.
Medicina (Kaunas) ; 60(5)2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38793022

RESUMO

Background and Objectives: Endoscopic epidural neuroplasty (EEN) facilitates adhesiolysis through direct epiduroscopic visualization, offering more precise neural decompression than that exhibited by percutaneous epidural neuroplasty (PEN). We aimed to compare the effects of EEN and PEN for 6 months after treatment with lower back and radicular pain in patients. Methods: This retrospective study compared the visual analog scale (VAS) and Oswestry disability index (ODI) scores in patients with low back and radicular pain who underwent EEN or PEN with a steering catheter. The medical records of 107 patients were analyzed, with 73 and 34 undergoing EEN and PEN, respectively. Results: The VAS and ODI scores decreased at all time points after EEN and PEN. VAS and ODI scores decreased more in the EEN group than those in the PEN group at 1 day and 1- and 6-months post-procedure, indicating superior pain relief for both lower back and radicular pain through EEN. Conclusions: EEN is a superior treatment of pain control than PEN in lower back and radicular pain patients.


Assuntos
Dor Lombar , Humanos , Dor Lombar/cirurgia , Dor Lombar/terapia , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Seguimentos , Idoso , Adulto , Endoscopia/métodos , Medição da Dor/métodos , Espaço Epidural , Descompressão Cirúrgica/métodos
4.
Phys Chem Chem Phys ; 26(1): 76-84, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38013482

RESUMO

Lanthanide-incorporated crystals display the phenomenon of upconversion (UC), wherein near-infrared (NIR) light is converted into ultraviolet-visible (UV-Vis) emission with a narrow bandwidth. This unique photophysical property renders lanthanide UC materials highly promising for diverse applications. However, the limited quantum efficiency (∼3%) hinders the broader utilization of UC materials. Consequently, numerous studies have focused on overcoming this low efficiency. Notably, it has been observed that manipulation of the site symmetry in UC materials significantly enhances their UC efficiency. In this study, we investigate the UC enhancement of Er3+ incorporated BaTiO3 (E-BT) crystals through the introduction of oxygen vacancies (OV). The OV were created using a post-heat treatment method, and the annealing time was varied to control the quantity of OV. An optimal annealing time of 6 hours was determined for efficient OV generation, beyond which the OV content decreased. Remarkably, E-BT crystals with OV exhibited up to three-fold greater UC compared to those without OV. This outcome suggests that OV induce symmetry changes in the E-BT crystal structure. Furthermore, the degree of UC enhancement in E-BT was found to be proportional to the amount of OV present.

5.
Metab Eng ; 69: 59-72, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34775076

RESUMO

The microbial conversion of glycerol into value-added commodity products has emerged as an attractive means to meet the demands of biosustainability. However, glycerol is a non-preferential carbon source for productive fermentation because of its low energy density. We employed evolutionary and metabolic engineering in tandem to construct an Escherichia coli strain with improved GABA production using glycerol as the feedstock carbon. Adaptive evolution of E. coli W under glycerol-limited conditions for 1300 generations harnessed an adapted strain with a metabolic system optimized for glycerol utilization. Mutation profiling, enzyme kinetic assays, and transcriptome analysis of the adapted strain allowed us to decipher the basis of glycerol adaptation at the molecular level. Importantly, increased substrate influx mediated by the mutant glpK and modulation of intracellular cAMP levels were the key drivers of improved fitness in the glycerol-limited condition. Leveraging the enhanced capability of glycerol utilization in the strain, we constructed a GABA-producing E. coli W-derivative with superior GABA production compared to the wild-type. Furthermore, rationally designed inactivation of the non-essential metabolic genes, including ackA, mgsA, and gabT, in the glycerol-adapted strain improved the final GABA titer and specific productivity by 3.9- and 4.3-fold, respectively, compared with the wild-type.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Carbono/metabolismo , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Fermentação , Glicerol/metabolismo , Laboratórios , Engenharia Metabólica , Ácido gama-Aminobutírico/genética
6.
Nucleic Acids Res ; 48(16): 9406-9413, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32810265

RESUMO

Eukaryotic protein synthesis is an inherently stochastic process. This stochasticity stems not only from variations in cell content between cells but also from thermodynamic fluctuations in a single cell. Ultimately, these inherently stochastic processes manifest as noise in gene expression, where even genetically identical cells in the same environment exhibit variation in their protein abundances. In order to elucidate the underlying sources that contribute to gene expression noise, we quantify the contribution of each step within the process of protein synthesis along the central dogma. We uncouple gene expression at the transcriptional, translational, and post-translational level using custom engineered circuits stably integrated in human cells using CRISPR. We provide a generalized framework to approximate intrinsic and extrinsic noise in a population of cells expressing an unbalanced two-reporter system. Our decomposition shows that the majority of intrinsic fluctuations stem from transcription and that coupling the two genes along the central dogma forces the fluctuations to propagate and accumulate along the same path, resulting in increased observed global correlation between the products.


Assuntos
Sistemas CRISPR-Cas/genética , Edição de Genes , Genoma Humano/genética , Transcrição Gênica , Linhagem Celular , Regulação da Expressão Gênica/genética , Humanos , Modelos Genéticos , Biossíntese de Proteínas/genética , Processos Estocásticos
7.
World J Urol ; 39(2): 407-413, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32335733

RESUMO

PURPOSE: Urological oncologists have difficulty providing optimal personalized care due to rapid alterations in scientific research results, medical advancements, and treatment guidelines. IBM's Watson for Oncology (WFO) is an artificial intelligence clinical decision-support system that assists oncologists with evidence-based treatment recommendations. In the present study, we examined the level of concordance between the treatment recommendations for prostate cancer according to WFO and the actual treatments that the patients received in the department of urology. METHODS: We enrolled 201 patients who received prostate cancer treatment between January 2018 and June 2018. WFO provided treatment recommendations using clinical data in three categories: recommended, for consideration, and not recommended. These were compared with the actual treatments received by patients. Prostate cancer treatments were considered concordant if the received treatments were included in the "recommended" or "for consideration" categories by WFO. RESULTS: The patients' mean age was 71.2 years. There were 60 (29.9%) and 114 (56.7%) patients with an Eastern Cooperative Oncology Group (ECOG) performance score ≥ 1 and non-organ confined disease (stage III/IV), respectively. The overall prostate cancer treatment concordance rate was 73.6% ("recommended": 53.2%; "for consideration": 20.4%). An ECOG performance score ≥ 1 and older age (≥ 75 years) were significantly associated with discordance (p = 0.001 and p = 0.026, respectively) on multivariate analysis. CONCLUSION: In the present study, the treatment recommendations by WFO and the actual received treatments in the department of urology showed a relatively high concordance rate in prostate cancer patients.


Assuntos
Inteligência Artificial , Sistemas de Apoio a Decisões Clínicas , Oncologia/métodos , Neoplasias da Próstata/terapia , Urologia/métodos , Humanos , Masculino , Guias de Prática Clínica como Assunto
8.
Phys Chem Chem Phys ; 23(27): 14587-14591, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34179911

RESUMO

Lanthanide incorporated perovskite is one of the most promising systems for efficient energy conversion or light-emitting materials in terms of upconversion (UC). Investigation of the photophysical mechanism of UC in the lanthanide-doped system is here continued. However, research on the 4I13/2 energy state in Er3+ is rare and more is still needed. In our work, BaTiO3:Er3+ (E-BT) was irradiated by a 1532 nm laser which is a resonance to the energy between 4I13/2 and the ground 4I15/2 state in Er3+. Bright 1532 nm-pumped UC was generated, and the UC color changed from red to yellow under increasing laser power. In addition, pump-power-dependent UC contained interesting clues about the photophysical pathway of UC. By analyzing photon numbers for each UC (green: 2H11/2/4S3/2 → 4I15/2, red: 4F9/2 → 4I15/2, infrared: 4I9/2 → 4I15/2), we found that changes in photon number with pump-power increase contain three different phases (P). P1 is a red UC phase with a small cross-relaxation between Er3+ ions. However, in P2, there is a rapid decrease in the photon number with green UC generation, which is due to the enhancement of 4I13/2-populating cross-relaxation. Finally, in P3, a saturated 4I13/2 state causes little increase of photon number (compared with P2), with different mechanistic cross-relaxation enhancement. With these three different phases under 1532 nm pumping, photophysical mechanisms in E-BT are interpreted.

9.
J Chem Phys ; 154(5): 054701, 2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33557550

RESUMO

Despite advances of lanthanide-doped upconversion (UC) materials, the applications such as light-emitting diode and biological imaging are limited by low quantum efficiency. For this context, the understanding of unique interactions between the doped-lanthanides and the host crystals has attracted a huge amount of the researcher's interest. In particular, it was revealed that doping lanthanide ions in a non-centrosymmetric site of host lattice is the cause of relaxation of the Laporte selection rule in the 4f-4f transition of lanthanide ions. One of the layered perovskites CsBiNb2O7 is known to have non-centrosymmetric sites, which would lead to highly bright UC emission. Nevertheless, to our knowledge, there has been no research on the UC comparison between host materials of CsBiNb2O7 with other hosts. In this article, we present the UC intensity comparison of Yb3+-Er3+ ion doped CsBiNb2O7, NaYF4, BaTiO3, and SrTiO3 hosts (the UC in CsBiNb2O7:Er3+,Yb3+ was 2.4 times that of NaYF4:Er3+,Yb3+ and ∼70 times that of SrTiO3:Er3+,Yb3+). After that, we dig into UC, downshifting, and double beam system UC properties. The activator concentration was optimized by varying the doping ratio of Yb3+ and Er3+, and we found out the main reason for the concentration quenching behavior in Er3+ ion doped CsBiNb2O7 is dipole-dipole interaction. In addition, the double excitation experiment indicates that the absorption (4I15/2 → 4I13/2) factor is stronger than the stimulated emission (4I13/2 → 4I15/2) factor in CsBiNb2O7 under 1540 nm laser irradiation.

10.
BMC Urol ; 21(1): 85, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34039340

RESUMO

BACKGROUND: Recent reports show that the pre-operative or post-operative skeletal mass index (sarcopenia) affects survival rates for various cancers; however, the link between prostate cancer survival and sarcopenia is unclear. Therefore, this study examined the effect of the pre-operative internal obturator muscle (IOM) mass index on biochemical recurrence (BCR) of prostate cancer (PCa) patients who underwent radical prostatectomy. METHODS: In total, 222 patients, who underwent open, laparoscopic, or robot-assisted radical prostatectomy at seven centers in 2011 and were followed up for 5 years, were enrolled. BCR was examined in the context of pre-operative IOM mass index and BMI. RESULTS: The mean age of the patients was 67.82 ± 6.23 years, and the mean pre-operative prostate-specific antigen (PSA) level was 11.61 ± 13.22 ng/ml. There was no significant difference in baseline characteristics between the low and high IOM mass index groups (p > 0.05). Age, pre-op PSA level, ECE, and T-stage were associated with BCR (p = 0.049, p < 0.001, p = 0.001, p = 0.004, respectively). BMI, prostate volume, Gleason score, resection margin, N-stage, M-stage and IOM mass index was not associated with BCR (p > 0.05). CONCLUSIONS: Pre-operative IOM mass index was not associated with BCR; however, long-term follow-up is necessary to evaluate cancer-specific and overall survival of PCa patients.


Assuntos
Imageamento por Ressonância Magnética , Músculo Esquelético/diagnóstico por imagem , Recidiva Local de Neoplasia , Prostatectomia , Neoplasias da Próstata/cirurgia , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/anatomia & histologia , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/mortalidade , Período Pré-Operatório , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/mortalidade , Taxa de Sobrevida
11.
Biochem Biophys Res Commun ; 527(3): 778-784, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32444142

RESUMO

Pyruvate dehydrogenase kinase (PDK) controls the activity of pyruvate decarboxylase complex (PDC) by phosphorylating key serine residues on the E1 subunit, which leads to a decreased oxidative phosphorylation in mitochondria. Inhibition of PDK activity by natural/synthetic compounds has been shown to reverse the Warburg effect, a characteristic metabolism in cancer cells. PDK-PDC axis also has been associated with diabetes and heart disease. Therefore, regulation of PDK activity has been considered as a promising strategy to treat related diseases. Here we present the X-ray crystal structure of PDK2 complexed with a recently identified PDK4 inhibitor, compound 8c, which has been predicted to bind at the lipoyl-binding site and interrupt intermolecular interactions with the E2-E3bp subunits of PDC. The co-crystal structure confirmed the specific binding location of compound 8c and revealed the remote conformational change in the ATP-binding pocket. In addition, two novel 4,5-diarylisoxazole derivatives, GM10030 and GM67520, were synthesized and used for structural studies, which target the ATP-binding site of PDK2. These compounds bind to PDK2 with a sub-100nM affinity as determined by isothermal titration calorimetry experiments. Notably, the crystal structure of the PDK2-GM10030 complex displays unprecedented asymmetric conformation of human PDK2 dimer, especially in the ATP-lids and C-terminal tails.


Assuntos
Trifosfato de Adenosina/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Piruvato Desidrogenase Quinase de Transferência de Acetil/antagonistas & inibidores , Regulação Alostérica/efeitos dos fármacos , Sítios de Ligação/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , Células HeLa , Humanos , Modelos Moleculares , Conformação Proteica/efeitos dos fármacos , Inibidores de Proteínas Quinases/química , Piruvato Desidrogenase Quinase de Transferência de Acetil/química , Piruvato Desidrogenase Quinase de Transferência de Acetil/metabolismo
12.
Int J Mol Sci ; 21(1)2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31906413

RESUMO

Muscle invasive bladder carcinoma is a highly malignant cancer with a high mortality rate, due to its tendency to metastasize. The tyrosine kinase recepteur d'origine nantais (RON) promotes bladder carcinoma metastasis. Lysophosphatidic acid (LPA) is a phospholipid derivative, which acts as a signaling molecule to activate three high affinity G-protein coupled receptors, LPA1, LPA2, and LPA3. This in turn leads to cell proliferation and contributes to oncogenesis. However, little is known about the effects of LPA on invasive bladder cancer (IBC). In this study, we discovered that LPA upregulated RON expression, which in turn promoted cell invasion in bladder cancer T24 cells. As expected, we found that the LPA receptor was essential for the LPA induced increase in RON expression. More interestingly, we discovered that LPA induced RON expression via the MAPK (ERK1/2, JNK1/2), Egr-1, AP-1, and NF-κB signaling axes. These results provide experimental evidence and novel insights regarding bladder malignancy metastasis, which could be helpful for developing new therapeutic strategies for IBC treatment.


Assuntos
Movimento Celular/efeitos dos fármacos , Lisofosfolipídeos/farmacologia , Receptores Proteína Tirosina Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Neoplasias da Bexiga Urinária/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proteína 1 de Resposta de Crescimento Precoce/antagonistas & inibidores , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Humanos , NF-kappa B/metabolismo , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Receptores Proteína Tirosina Quinases/genética , Receptores de Ácidos Lisofosfatídicos/antagonistas & inibidores , Receptores de Ácidos Lisofosfatídicos/genética , Receptores de Ácidos Lisofosfatídicos/metabolismo , Fator de Transcrição AP-1/antagonistas & inibidores , Fator de Transcrição AP-1/metabolismo , Neoplasias da Bexiga Urinária/metabolismo
13.
Neurourol Urodyn ; 38(1): 295-304, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30311691

RESUMO

AIMS: To evaluate the efficacy and safety of mirabegron in males with overactive bladder (OAB) symptoms. METHODS: In total, 464 males with OAB symptoms were enrolled from 14 institutes and were sorted into either the mirabegron 50 mg (n = 310) or placebo (n = 154) groups. The change in (i) the mean number of 24-h micturition episodes; (ii) OAB Symptom Scale (OABSS); and (iii) International Prostate Symptom Score (IPSS) from baseline to 12 weeks of treatment were compared between the two groups. Safety assessments included treatment-emergent adverse events, blood pressure, pulse rate, postvoid residual volume, and maximum urinary flow rate. After 12 weeks, the study was extended for 14 additional weeks by administering mirabegron 50 mg to both groups. RESULTS: The reduction in the mean number of 24-h micturition episodes from baseline to 12 weeks of treatment was similar between the two groups. However, significantly greater changes from baseline to 12 weeks were observed in total OABSS, OABSS urgency incontinence score (Q4), IPSS storage subscore (Q2 + Q4 + Q7), and IPSS urgency score (Q4) in the mirabegron group (P = 0.01 for all). According to the extended study, the changes of all efficacy variables from baseline to 26 weeks were similar between both groups. The safety assessment results were also similar between the two groups at 12 and 26 weeks. CONCLUSION: A daily 50 mg dose of mirabegron for 12 weeks reduced OAB symptoms in men, and no significant adverse events compared to the placebo group were noted.


Assuntos
Acetanilidas/uso terapêutico , Tiazóis/uso terapêutico , Bexiga Urinária Hiperativa/tratamento farmacológico , Agentes Urológicos/uso terapêutico , Acetanilidas/administração & dosagem , Acetanilidas/efeitos adversos , Idoso , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tiazóis/administração & dosagem , Tiazóis/efeitos adversos , Resultado do Tratamento , Micção/efeitos dos fármacos , Agentes Urológicos/administração & dosagem , Agentes Urológicos/efeitos adversos
14.
Int J Mol Sci ; 20(6)2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-30901823

RESUMO

Lanthanide-doped upconversion nanoparticles (UCNPs) are inorganic nanomaterials in which the lanthanide cations embedded in the host matrix can convert incident near-infrared light to visible or ultraviolet light. These particles are often used for long-term and real-time imaging because they are extremely stable even when subjected to continuous irradiation for a long time. It is now possible to image their movement at the single particle level with a scale of a few nanometers and track their trajectories as a function of time with a scale of a few microseconds. Such UCNP-based single-particle tracking (SPT) technology provides information about the intracellular structures and dynamics in living cells. Thus far, most imaging techniques have been built on fluorescence microscopic techniques (epifluorescence, total internal reflection, etc.). However, two-dimensional (2D) images obtained using these techniques are limited in only being able to visualize those on the focal planes of the objective lens. On the contrary, if three-dimensional (3D) structures and dynamics are known, deeper insights into the biology of the thick cells and tissues can be obtained. In this review, we introduce the status of the fluorescence imaging techniques, discuss the mathematical description of SPT, and outline the past few studies using UCNPs as imaging probes or biologically functionalized carriers.


Assuntos
Rastreamento de Células , Nanopartículas/química , Nanopartículas/metabolismo , Transporte Biológico , Sistemas de Liberação de Medicamentos , Imunofluorescência , Imageamento Tridimensional , Microscopia de Fluorescência , Imagem Molecular , Nanotecnologia
15.
Int Braz J Urol ; 45(2): 402-405, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30735338

RESUMO

Primary angiosarcomas of the kidney are very rare, but highly aggressive tumors showing poor prognosis. Patients frequently complain of flank pain, hematuria, or a palpable mass. We present a case of primary renal angiosarcoma occurring in a 61-year-old man. CT images depicted a huge exophytic mass (16 cm in diameter) in the right kidney, exhibiting extensive hemorrhage. The mass showed centripetal peripheral nodular enhancement on dynamic contrast-enhanced images. Furthermore, MR imaging revealed a tangled mesh of tumor vessels in the periphery of the mass. We suggest its inclusion in the differential diagnosis of cases of hemorrhagic renal tumors with prominent vasculature.


Assuntos
Hemangiossarcoma/diagnóstico por imagem , Neoplasias Renais/diagnóstico por imagem , Hemangiossarcoma/patologia , Humanos , Neoplasias Renais/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
16.
Phys Chem Chem Phys ; 20(16): 11359-11368, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29644351

RESUMO

Understanding the interaction of nanoparticles with living cells on the basis of cellular uptake efficiency is a fundamental requisite in biomedical research. Cellular internalization of nanoparticles takes place by mechanisms like ATP hydrolysis-driven endocytosis that deliver nanoparticles to the cytoplasm, organelles and nuclei. Despite its importance in nanomedicine, this uptake procedure is not understood in-depth because of the complexity of the biochemical mechanisms and the lack of available experimental methods for quantitative analysis. The only breakthrough is likely to be the development of imaging techniques that can visualize, monitor and even count the number of nanoparticles inside the cell. To this end, we report here a new, fast and background-free three-dimensional (3-D) imaging technique with quantitative evaluation of the uptake efficiency for NaYF4:Yb3+,Er3+/NaYF4 core/shell upconversion nanoparticles (UCNPs) functionalized with different chemical and biological groups. Furthermore, the multiple 3-D trajectories of the UCNPs have been analyzed to investigate the cellular dynamics. This study reveals the nuclear uptake of UCNPs to be dependent on the specific chemical groups conjugated to the UCNPs. The developed 3-D imaging technique is of great significance for exploring complex biological systems.


Assuntos
Imageamento Tridimensional/métodos , Nanopartículas/metabolismo , Érbio/química , Fluorescência , Fluoretos/química , Células HeLa , Humanos , Microscopia de Fluorescência , Nanopartículas/química , Itérbio/química , Ítrio/química
17.
Proc Natl Acad Sci U S A ; 112(41): 12893-8, 2015 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-26420864

RESUMO

Reverse engineering of biological pathways involves an iterative process between experiments, data processing, and theoretical analysis. Despite concurrent advances in quality and quantity of data as well as computing resources and algorithms, difficulties in deciphering direct and indirect network connections are prevalent. Here, we adopt the notions of abstraction, emulation, benchmarking, and validation in the context of discovering features specific to this family of connectivities. After subjecting benchmark synthetic circuits to perturbations, we inferred the network connections using a combination of nonparametric single-cell data resampling and modular response analysis. Intriguingly, we discovered that recovered weights of specific network edges undergo divergent shifts under differential perturbations, and that the particular behavior is markedly different between topologies. Our results point to a conceptual advance for reverse engineering beyond weight inference. Investigating topological changes under differential perturbations may address the longstanding problem of discriminating direct and indirect connectivities in biological networks.


Assuntos
Algoritmos , Modelos Biológicos , Biologia Sintética , Células HEK293 , Humanos
18.
Int J Urol ; 25(5): 414-419, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29478297

RESUMO

OBJECTIVES: To evaluate the surgical feasibility of laparoscopic adrenalectomy using the lateral retroperitoneal approach for the treatment of large pheochromocytomas, and to identify the preoperative risk factors for intraoperative hypertension. METHODS: We retrospectively reviewed 51 patients who underwent laparoscopic adrenalectomy using the lateral retroperitoneal approach for the treatment of pheochromocytomas. Patient characteristics and perioperative outcomes were analyzed and compared between the two study groups based on tumor size: group A (n = 27, ≤6 cm) and group B (n = 24, ˃6 cm). RESULTS: There was no significant difference in preoperative characteristics between the two groups except for tumor size (P = 0.001) and urinary metanephrine (P = 0.011). Group B patients required longer operating time (P = 0.008), had a greater estimated blood loss (P = 0.001) and hemoglobin change (P = 0.002). However, no significant differences were observed in perioperative complications and mortality. Multivariate analysis showed that symptomatic pheochromocytomas (P = 0.004) and tumor size (P = 0.007) were significant risk factors for intraoperative hypertension. CONCLUSIONS: Laparoscopic adrenalectomy using the lateral retroperitoneal approach for pheochromocytomas can be regarded as a treatment option, even for tumors measuring >6 cm. Symptomatic pheochromocytomas and large tumor size seem to represent risk factors for intraoperative hypertension.


Assuntos
Neoplasias das Glândulas Suprarrenais/cirurgia , Adrenalectomia/efeitos adversos , Adrenalectomia/métodos , Hipertensão/etiologia , Laparoscopia/efeitos adversos , Feocromocitoma/cirurgia , Adulto , Feminino , Humanos , Complicações Intraoperatórias , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Duração da Cirurgia , Assistência Perioperatória , Complicações Pós-Operatórias , República da Coreia , Espaço Retroperitoneal/cirurgia , Estudos Retrospectivos , Fatores de Risco
19.
Anal Biochem ; 532: 38-44, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28600127

RESUMO

A myc-tag and of which recognition by an antibody 9E10 has long been used for the detection and purification of recombinant proteins. We have previously expanded the application of the tag to the specific detection and purification of backbone-cyclized proteins. Here we sought a more practical way to using the 9E10 antibody by expressing its single chain antibody (scAb) form in Escherichia coli. The combined use of a strong T7 promoter and auto-induction strategy rather than early to mid-log induction of a Lac promoter resulted in the soluble over-expression of 9E10 scAb. However, the co-expression of a chaperone, Skp, was absolutely necessary for the activity even when the protein was expressed in a soluble manner. We could purify about 4 mg of 9E10 scAb from 1 l of culture, and the resulting scAb could be used to detect and purify the backbone-cyclized protein as the parental full-length 9E10. Moreover, the immunoaffinity resin prepared using 9E10 scAb could be regenerated several times after the elution of bound proteins using an acid, which added more value to the ready preparation of the active antibody in bacteria.


Assuntos
Escherichia coli/metabolismo , Proteínas de Fluorescência Verde/análise , Engenharia de Proteínas/métodos , Proteínas Proto-Oncogênicas c-myc/imunologia , Proteínas Recombinantes de Fusão/análise , Anticorpos de Cadeia Única/análise , Ciclização , Proteínas de Ligação a DNA/metabolismo , Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/imunologia , Chaperonas Moleculares/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/imunologia
20.
Phys Chem Chem Phys ; 19(15): 9739-9744, 2017 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-28367577

RESUMO

Upconversion nanoparticles (UCNPs) have attracted enormous interest over the past few years because of their unique optical properties and potential for use in various applications such as bioimaging probes, biosensors, and light-harvesting materials for photovoltaics. The improvement of imaging resolution is one of the most important goals for UCNPs used in biological applications. Super-resolution imaging techniques that overcome the fundamental diffraction limit of light rely on the photochemistry of organic dyes or fluorescent proteins. Here we report our progress toward super-resolution microscopy with UCNPs. We found that the red emission (655 nm) of core/shell UCNPs with the structure NaYF4:Yb3+,Er3+/NaYF4 could be modulated by emission depletion (ED) of the intermediate state that interacts resonantly with an infrared beam (1540 nm). In contrast, the green emission bands (525 and 545 nm) of the UCNPs were less affected by irradiation with the infrared beam. The origin of such distinct behaviors between the green and red emissions was attributed to their different photophysical pathways.

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