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1.
J Neurosci ; 43(23): 4304-4314, 2023 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-37137705

RESUMEN

The what, where, and when components of episodic memory can be differentiated based on their distinctive domain-specific underlying neural correlates. However, recent studies have proposed that a common neural mechanism of conceptual mapping may be involved in the coding of cognitive distance across all domains. In this study, we provide evidence that both domain-specific and domain-general processes occur simultaneously during memory retrieval by identifying distinctive and common neural representations for mapping what (i.e., semantic distance), where (i.e., spatial distance), and when (i.e., temporal distance) using scalp EEG from 47 healthy participants (age 21-30, 26 male and 21 female). First, we found that all three components commonly showed a positive correlation between cognitive distance and slow theta power (2.5-5 Hz) in parietal channels. Meanwhile, fast theta power (5-8.5 Hz) specifically represented spatial and temporal distance in occipital and parietal channels, respectively. Additionally, we identified a unique correlate of temporal distance coding in frontal/parietal slow theta power during the early phase of retrieval. All of the above neural markers of cognitive mapping, both domain-general and specific, were associated with individual differences in what, where, and when memory accuracy.SIGNIFICANCE STATEMENT The Cognitive Map Theory was originally founded to explain how we remember and organize the immense amount of spatial information that we face when we navigate. However, memory research has recently trended in the direction of emphasizing the generalizability of cognitive mapping mechanisms to information in any domain, represented as distances in an abstract conceptual space. In a single study, we show that both common and unique neural coding of semantic distance (i.e., what), spatial distance (i.e., where), and temporal distance (i.e., when) simultaneously support episodic memory retrieval. Our results suggest that our ability to accurately distinguish between memories is achieved through an integration of domain-specific and domain-general neurocognitive mechanisms that work in parallel.


Asunto(s)
Mapeo Encefálico , Memoria Episódica , Humanos , Masculino , Femenino , Adulto Joven , Adulto , Recuerdo Mental/fisiología , Electroencefalografía , Cognición
2.
J Immunol ; 208(3): 772-779, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-35022271

RESUMEN

Human IgE is useful for immunological assays, such as sensitization of FcεRI-positive cells and IgE measurement. In this study, we report the development of a recombinant Ig fragment, designated IgCw-γεκ, as an alternative reagent to human IgE. IgCw-γεκ (∼130 kDa) comprises two hybrid constant H chain regions (Cγ1-Cε2-4, each ∼53 kDa) and two constant κ L chains (Cκ, each ∼12 kDa) and lacks a V domain. The presence of Cγ1 instead of Cε1 within the H chain increased the production yield and facilitated assembly of the H and L chains. IgCw-γεκ was produced in cultured human embryonic kidney 293F cells, with a yield of ∼27 mg/l. IgCw-γεκ bound to human FcεRIαRs expressed on the surface of rat basophilic leukemia-2H3 cells. A ß-hexosaminidase release assay revealed that the biological activity of IgCw-γεκ was comparable with that of IgE. The IgE concentration measured using IgCw-γεκ as a standard was similar to that measured using IgE as a standard. These results suggest that the IgCw-γεκ molecule retains the basic characteristics of IgE, but does not cross-react with Ags, making it an alternative to the IgE isotype references used in a variety of immunological assays.


Asunto(s)
Inmunoglobulina E/inmunología , Fragmentos de Inmunoglobulinas/genética , Fragmentos de Inmunoglobulinas/inmunología , Cadenas Pesadas de Inmunoglobulina/inmunología , Cadenas kappa de Inmunoglobulina/inmunología , Animales , Línea Celular , Células HEK293 , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas kappa de Inmunoglobulina/genética , Indicadores y Reactivos , Ratas , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología
3.
Mol Cell ; 62(6): 811-823, 2016 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-27237053

RESUMEN

Throughout the bacterial domain, the alarmone ppGpp dramatically reprograms transcription following nutrient limitation. This "stringent response" is critical for survival and antibiotic tolerance and is a model for transcriptional regulation by small ligands. We report that ppGpp binds to two distinct sites 60 Å apart on E. coli RNA polymerase (RNAP), one characterized previously (site 1) and a second identified here at an interface of RNAP and the transcription factor DksA (site 2). The location and unusual tripartite nature of site 2 account for the DksA-ppGpp synergism and suggest mechanisms for ppGpp enhancement of DksA's effects on RNAP. Site 2 binding results in the majority of ppGpp's effects on transcription initiation in vitro and in vivo, and strains lacking site 2 are severely impaired for growth following nutritional shifts. Filling of the two sites at different ppGpp concentrations would expand the dynamic range of cellular responses to changes in ppGpp levels.


Asunto(s)
ARN Polimerasas Dirigidas por ADN/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Guanosina Tetrafosfato/metabolismo , Estrés Fisiológico , Iniciación de la Transcripción Genética , Secuencia de Aminoácidos , Sitios de Unión , Secuencia Conservada , ARN Polimerasas Dirigidas por ADN/química , ARN Polimerasas Dirigidas por ADN/genética , Escherichia coli/genética , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Evolución Molecular , Regulación Bacteriana de la Expresión Génica , Modelos Moleculares , Unión Proteica , Conformación Proteica , Relación Estructura-Actividad
4.
J Cogn Neurosci ; 35(11): 1773-1787, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37584602

RESUMEN

Despite distinct neural representation of what, where, and when information, studies of individual differences in episodic memory have neglected to test the three components separately. Here, we used a componential episodic memory task to measure cognitive profiles across a wide age range and in Alzheimer disease (AD) and to examine the role of theta oscillations in explaining performance. In Experiment 1, we tested a group of 47 young adults (age 21-30 years, 21 women) while recording their scalp EEG. A separate behavioral experiment (Experiment 2) was performed in 42 older adults (age 66-85 years, 29 women) and in a group of 16 AD patients (age 80-90 years, 12 women). In Experiment 1, K-means clustering based on behavioral data resulted in three "cognotypes" whose memory profiles showed corresponding differences in their EEG markers: What and where memory depended on frontal theta power and when memory depended on theta modulation by temporal distance between retrieved items. In Experiment 2, healthy older adults showed three cognotypes similar to those found in younger adults; moreover, AD patients had an overlapping profile with one specific cognotype, characterized by marked difficulties in when memory. These findings highlight the utility of componential episodic memory tests and cognotyping in understanding individual strengths and vulnerabilities in age-related neurocognitive decline.

5.
J Immunol ; 206(3): 481-493, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-33380497

RESUMEN

B cells in the germinal center (GC) are programmed to form plasma cells (PCs) or memory B cells according to signals received by receptors that are translated to carry out appropriate activities of transcription factors. However, the precise mechanism underlying this process to complete the GC reaction is unclear. In this study, we show that both genetic ablation and pharmacological inhibition of glycogen synthase kinase 3 (GSK3) in GC B cells of mice facilitate the cell fate decision toward PC formation, accompanied by acquisition of dark zone B cell properties. Mechanistically, under stimulation with CD40L and IL-21, GSK3 inactivation synergistically induced the transcription factors Foxo1 and c-Myc, leading to increased levels of key transcription factors required for PC differentiation, including IRF4. This GSK3-mediated alteration of transcriptional factors in turn facilitated the dark zone transition and consequent PC fate commitment. Our study thus reveals the upstream master regulator responsible for interpreting external cues in GC B cells to form PCs mediated by key transcription factors.


Asunto(s)
Linfocitos B/inmunología , Centro Germinal/inmunología , Glucógeno Sintasa Quinasa 3/metabolismo , Células Plasmáticas/inmunología , Animales , Ligando de CD40/metabolismo , Diferenciación Celular , Células Cultivadas , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Regulación de la Expresión Génica , Glucógeno Sintasa Quinasa 3/genética , Factores Reguladores del Interferón/genética , Factores Reguladores del Interferón/metabolismo , Interleucinas/metabolismo , Activación de Linfocitos , Ratones , Ratones Noqueados , Proteínas Proto-Oncogénicas c-myb/genética , Proteínas Proto-Oncogénicas c-myb/metabolismo
6.
Anal Chem ; 94(21): 7449-7454, 2022 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-35583342

RESUMEN

Nanopore sensors are a highly attractive platform for single-molecule sensing for sequencing, disease diagnostics, and drug screening. Outer membrane protein G (OmpG) nanopores have advantages for single-molecule sensing owing to their rigid monomeric structure, which comprises seven flexible loops, providing distinct gating patterns upon analyte binding. Blocking of the protein-protein interaction between B-cell lymphoma-extra-large (Bcl-xL) and the BH3 domain of Bcl-2 homologous antagonist/killer (Bak-BH3) has been reported as a promising strategy for anticancer therapy. Here, we characterized the interaction between Bcl-xL and Bak-BH3 as well as its inhibition by a small-molecule inhibitor using click chemistry-based Bak-BH3 peptide-conjugated OmpG nanopores. The binding of Bcl-xL to Bak-BH3 generated characteristic gating signals involving significant changes in the amplitudes of noise and gating parameters such as gating frequency, open probability, and durations of open and closed states. Notably, specific inhibition of Bcl-xL by the small-molecule antagonist, ABT-737, led to the recovery of the noise and gating parameters. Collectively, these results revealed that the chemically modified OmpG nanopore can serve as a valuable sensor platform for ultrasensitive, rapid, and single-molecule-based drug screening against protein-protein interactions, which are therapeutic targets for various diseases.


Asunto(s)
Proteínas de Escherichia coli , Nanoporos , Apoptosis , Proteínas de la Membrana Bacteriana Externa/química , Proteínas de Escherichia coli/metabolismo , Nanotecnología , Porinas/química , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteína bcl-X/metabolismo
7.
Surg Radiol Anat ; 43(2): 261-266, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32960307

RESUMEN

The present study applied a three-dimensional (3D) program to measure the distances from the maxillary sinus floor (MSF) to the lingual and buccal alveolar bone and also to the posterior superior alveolar foramen (PSAF), with the aim of determining differences according to gender. The study also attempted to verify the accuracy of measurements obtained from 3D images by performing comparisons with the results obtained in a preliminary study. The results showed that the alveolar bone length and the MAF-PSAF were generally larger in males than in females. It is also predicted that the accuracy of data obtained from a 3D program will be higher than that of data derived from conventional two-dimensional (2D) images. The accurate measurements obtained in this study are anticipated to prove useful in assessments related to dental implantation and anatomical structures. The fundamental data obtained in this study may also assist in setting the goals of future studies utilizing 3D programs.


Asunto(s)
Proceso Alveolar/anatomía & histología , Tomografía Computarizada de Haz Cónico/métodos , Implantación Dental/métodos , Imagenología Tridimensional , Seno Maxilar/anatomía & histología , Adulto , Proceso Alveolar/diagnóstico por imagen , Proceso Alveolar/cirugía , Estudios de Factibilidad , Femenino , Humanos , Masculino , Seno Maxilar/diagnóstico por imagen , Factores Sexuales , Adulto Joven
8.
Genes Dev ; 26(23): 2634-46, 2012 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-23207918

RESUMEN

Escherichia coli DksA is a transcription factor that binds to RNA polymerase (RNAP) without binding to DNA, destabilizing RNAP-promoter interactions, sensitizing RNAP to the global regulator ppGpp, and regulating transcription of several hundred target genes, including those encoding rRNA. Previously, we described promoter sequences and kinetic properties that account for DksA's promoter specificity, but how DksA exerts its effects on RNAP has remained unclear. To better understand DksA's mechanism of action, we incorporated benzoyl-phenylalanine at specific positions in DksA and mapped its cross-links to RNAP, constraining computational docking of the two proteins. The resulting evidence-based model of the DksA-RNAP complex as well as additional genetic and biochemical approaches confirmed that DksA binds to the RNAP secondary channel, defined the orientation of DksA in the channel, and predicted a network of DksA interactions with RNAP that includes the rim helices and the mobile trigger loop (TL) domain. Engineered cysteine substitutions in the TL and DksA coiled-coil tip generated a disulfide bond between them, and the interacting residues were absolutely required for DksA function. We suggest that DksA traps the TL in a conformation that destabilizes promoter complexes, an interaction explaining the requirement for the DksA tip and its effects on transcription.


Asunto(s)
ARN Polimerasas Dirigidas por ADN/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Escherichia coli/enzimología , Regulación Bacteriana de la Expresión Génica , ARN Polimerasas Dirigidas por ADN/química , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/química , Modelos Moleculares , Fenilalanina/análogos & derivados , Fenilalanina/metabolismo , Regiones Promotoras Genéticas/genética , Unión Proteica , Estructura Terciaria de Proteína , Subunidades de Proteína/química , Subunidades de Proteína/metabolismo
9.
Biochem Biophys Res Commun ; 505(3): 872-878, 2018 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-30301528

RESUMEN

Helicobacter pylori is a flagellated bacterium of the Epsilonproteobacteria class that causes peptic ulcers. Flagellin is a primary structural protein that assembles into the flagellar filament. Flagellins from bacteria that belong to the Gammaproteobacteria and Firmicutes groups are detected by Toll-like receptor 5 (TLR5) in the host, triggering the innate immune response, and thus have been studied for the development of vaccines against diverse infections through fusion with protein antigens. However, H. pylori flagellin (hFlg) does not stimulate TLR5, allowing H. pylori to evade TLR5-mediated immune surveillance. The unresponsiveness of TLR5 to hFlg, along with the tendency of the hFlg protein to precipitate, limits the utility of hFlg for H. pylori vaccine development. Here, we report a soluble hFlg derivative protein that activates TLR5. We performed expression and purification screens with full-length and fragment hFlg proteins and identified the hypervariable domains as the soluble part of hFlg. The hypervariable domains of hFlg were engineered into a TLR5 agonist through fusion with the TLR5-activating Bacillus subtilis flagellin. Furthermore, based on comparative sequence and mutation analyses, we reveal that hFlg evolved to evade TLR5 detection by modifying residues that correspond to a TLR5-activation hot spot.


Asunto(s)
Flagelina/farmacología , Helicobacter pylori/química , Evasión Inmune , Ingeniería de Proteínas/métodos , Receptor Toll-Like 5/inmunología , Bacillus subtilis/química , Proteínas Bacterianas , Análisis Mutacional de ADN , Evolución Molecular , Solubilidad , Receptor Toll-Like 5/agonistas
10.
J Nanosci Nanotechnol ; 18(9): 5876-5881, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29677709

RESUMEN

In this study, we investigated the effects of hydrogen peroxide (H2O2) on solution-processed zirconium oxide (ZrO2) dielectric materials. The addition of H2O2 into ZrO2 dielectric showed a reduction in hysteresis capacitance-voltage characteristics (from 393 mV to 96 mV). This resulted in a reduction in border trap density (Nbt) of the ZrO2 film (ZrO2: 2.24 × 1011 cm-2, ZrO2 + H2O2: 3.96 × 1010 cm-2). In addition, use of H2O2 in the ZrO2 dielectric improved the interface quality. Specifically, the reduced number of trap sites improved the reliability of the device under a negative bias stress (NBS). The 350 °C annealed ZrO2 dielectric with H2O2 showed excellent leakage current properties (6.7 × 10-9 A/cm2 at gate voltage of -10 V). Based on these results, we fabricated IGZO/ZrO2 + H2O2 TFTs, which showed a high saturation mobility of 6.10 cm2/V · s and excellent switching properties. This study suggests that incorporation of H2O2 into ZrO2 effectively reduced oxygen vacancies through strong oxidation and minimized residual organics that cause impurities or structural defects, such as pores or pin holes, compared to a virgin ZrO2 film.

11.
J Nanosci Nanotechnol ; 18(9): 5908-5912, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29677715

RESUMEN

In this paper, we investigated the use of a mixed host emission layer (MH-EML) in green phosphorescent organic light-emitting diodes (OLEDs). The hole transport type (p-type) material (4,4'-Bis(N-carbazolyl)-1,1'-biphenyl (CBP)) and electron transport type (N-type) material (2,2',2″-(1,3,5-Benzinetriyl)-tris(1-phenyl-1-H-benzimidazole) (TPBi)) were mixed with different ratios. The electrons were easily injected through the lowest unoccupied molecular orbital (LUMO) of TPBi in the mixed host system. Also, holes were confined in the EML because of the deep highest occupied molecular orbital (HOMO) level of TPBi (6.7 eV). These results indicate that excitons were formed effectively and the recombination zone became wider under a high electric field in MH-EML devices. For these reasons, the lifetime of the MH-OLED device was 1.36 times higher than that of a single host emission layer (SH-EML) device and showed a reduction in Joule heating. Finally, the external quantum efficiency (EQE) roll-off ratio from 1 mA/cm2 to 100 mA/cm2 in the optimized device (30.46%) was 18.12%p lower than that of the SH-EML (48.58%).

12.
J Nanosci Nanotechnol ; 18(9): 5913-5918, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29677716

RESUMEN

Double stacked indium-zinc oxide (IZO)/zinc-tin oxide (ZTO) active layers were employed in amorphous-oxide-semiconductor thin-film transistors (AOS TFTs). Channel layers of the TFTs were optimized by varying the molarity of ZTO back channel layers (0.05, 0.1, 0.2, 0.3 M) and the electrical properties of IZO/ZTO double stacked TFTs were compared to single IZO and ZTO TFTs with varying the molarity and molar ratio. On the basis of the results, IZO/ZTO (0.1 M) TFTs showed the excellent electrical properties of saturation mobility (13.6 cm2/V·s), on-off ratio (7×106), and subthreshold swing (0.223 V/decade) compared to ZTO (0.1 M) of 0.73 cm2/V · s, 1 × 107, 0.416 V/decade and IZO (0.04 M) of 0.10 cm2/V · s, 5 × 106, 0.60 V/decade, respectively. This may be attributed to diffusing Sn into front layer during annealing process. In addition, with varying molarity of ZTO back channel layer, from 0.1 M to 0.3 M ZTO back channel TFTs, electrical properties and positive bias stability deteriorated with increasing molarity of back channel layer because of increasing total trap states. On the other hand, 0.05 M ZTO back channel TFT had inferior electrical properties than that of 0.1 M ZTO back channel TFT. It was related to back channel effect because of having thin thickness of channel layer. Among these devices, 0.1 M ZTO back channel TFT had a lowest total trap density, outstanding electrical properties and stability. Therefore, we recommended IZO/ZTO (0.1 M) TFT as a promising channel structure for advanced display applications.

13.
J Nanosci Nanotechnol ; 18(9): 6005-6009, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29677733

RESUMEN

In this study, the charge polarity of aluminum fluoride (AlF3) as a function of varying thickness (tAlF3 = 20, 35, 50, 65, and 80 nm) was discussed. AlF3 films were deposited onto p-Si wafers via electron beam sputtering. Thickness dependent charge polarity and reliability issues under bias-temperature stress conditions were identified using a capacitance-voltage (C-V) characterization method. AlF3 was found to possess negative fixed charges, leading to a C-V curve shift toward the positive gate bias direction as tAlF3 was increased up to 50 nm. On the contrary, the C-V characteristics were dominantly affected by the positive charges of mobile ions and/or fluorine vacancies when tAlF3 was increased to more than 50 nm. Additionally, negative bias temperature stress (1 MV/cm, 473 K for 10 mins) increased insulator trapped charges and decreased interface traps in 20 nm thick AlF3 films. These results could be attributed to positively charged fluorine vacancies introduced by broken Al-F bonds within AlF3 films and the passivation of Si dangling bonds due to broken fluorine ions at the interface, respectively. It was believed that 20 nm thick AlF3 films sufficiently attracted holes from the Si substrate, forming a hole accumulation layer on the surface due to total charge polarity of the AlF3 dielectric being entirely governed by negative fixed charges as the thickness of AlF3 decreased. Based on these results, AlF3 films are proposed for use as an anti-reflection layer to replace HfO2 in CMOS image sensors.

14.
Genes Dev ; 23(2): 236-48, 2009 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-19171784

RESUMEN

The Escherichia coli DksA protein inserts into the RNA polymerase (RNAP) secondary channel, modifying the transcription initiation complex so that promoters with specific kinetic characteristics are regulated by changes in the concentrations of ppGpp and NTPs. We used footprinting assays to determine the specific kinetic intermediate, RP(I), on which DksA acts. Genetic approaches identified substitutions in the RNAP switch regions, bridge helix, and trigger loop that mimicked, reduced, or enhanced DksA function on rRNA promoters. Our results indicate that DksA binding in the secondary channel of RP(I) disrupts interactions with promoter DNA at least 25 A away, between positions -6 and +6 (the transcription start site is +1). We propose a working model in which the trigger loop and bridge helix transmit effects of DksA to the switch region(s), allosterically affecting switch residues that control clamp opening/closing and/or that interact directly with promoter DNA. DksA thus inhibits the transition to RP(I). Our results illustrate in mechanistic terms how transcription factors can regulate initiation promoter-specifically without interacting directly with DNA.


Asunto(s)
Proteínas de Escherichia coli/metabolismo , Escherichia coli/fisiología , Regulación Bacteriana de la Expresión Génica , Regiones Promotoras Genéticas/genética , Regulación Alostérica , ARN Polimerasas Dirigidas por ADN/genética , Escherichia coli/química , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Guanosina Tetrafosfato/metabolismo , Modelos Moleculares , Estructura Terciaria de Proteína , Transducción de Señal , Supresión Genética
15.
Artif Organs ; 38(5): 411-7, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24571533

RESUMEN

Epigallocatechin-3-O-gallate (EGCG) is a major polyphenolic compound in green tea. It has been known that EGCG regulates the secretion of cytokines and the activation of skin cells during wound healing. In this study, various concentrations of EGCG were added to the electrospun membranes composed of poly (lactic-co-glycolic acid) (PLGA), and its healing effects on full-thickness wounds created in nude mice were investigated. The electrospun membranes containing 5 wt% EGCG (5EGCG/PLGA membrane) exhibited cytotoxicity in human dermal fibroblasts (HDFs) as HDF morphologies were transformed on them. In the animal study, cell infiltration of mice treated with electrospun membranes containing 1 wt% EGCG (1EGCG/PLGA membrane) significantly increased after 2 weeks. The immunoreactivity of Ki-67 (re-epithelialization at the wound site) and CD 31 (formation of blood vessels) also increased in the mice treated with 1EGCG/PLGA membranes in comparison with the mice treated with PLGA membranes. These results suggest that 1EGCG/PLGA can enhance wound healing in full thickness by accelerating cell infiltration, re-epithelialization, and angiogenesis.


Asunto(s)
Antioxidantes/uso terapéutico , Vendajes , Catequina/análogos & derivados , Ácido Láctico/química , Ácido Poliglicólico/química , Cicatrización de Heridas/efectos de los fármacos , Adulto , Animales , Antioxidantes/administración & dosificación , Catequina/administración & dosificación , Catequina/uso terapéutico , Línea Celular , Humanos , Masculino , Membranas Artificiales , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico
16.
J Pers Med ; 14(4)2024 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-38673042

RESUMEN

The nasal cavity constitutes the foremost portion of the respiratory system, composed of the anterior nasal aperture, nostrils, and choanae. It has an intricate anatomical structure since it has various functions, such as heat exchange, humidification, and filtration. Accordingly, clinical symptoms related to the nose, such as nasal congestion, snoring, and nasal septal deviation, are closely linked to the complex anatomical structure of the nasal cavity. Thus, the nasal cavity stands as a paramount structure in both forensic and clinical contexts. The majority of relevant studies have performed comparisons between sexes, with studies making comparisons according to the FI and NI only and examining relative percentages. Furthermore, the nasal cavity was measured in 2D, and not 3D, in most cases. In this study, we conducted a 3D modeling and anthropometric assessment of the nasal cavity using a 3D analysis software. Furthermore, we aimed to investigate whether the size of the nasal cavity differs according to sex, facial index (FI), and nasal index (NI). We retrospectively reviewed the cone-beam computed tomography (CBCT) data of 100 participants (50 males, 50 females) aged 20-29 years who visited the dental hospital of Dankook University (IRB approval no. DKUDH IRB 2020-01-007). Our findings showed that nasal cavity sizes generally differed according to sex, FI, and NI. These findings provide implications for performing patient-tailored surgeries in clinical practice and conducting further research on the nasal cavity. Therefore, we believe that our study makes a significant contribution to the literature.

17.
EMBO J ; 28(12): 1720-31, 2009 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-19424178

RESUMEN

At specific times during bacterial growth, the transcription factor DksA and the unusual nucleotide regulator ppGpp work synergistically to inhibit some Escherichia coli promoters (e.g. rRNA promoters) and to stimulate others (e.g. promoters for amino-acid synthesis and transport). However, the mechanism of DksA action remains uncertain, in part because DksA does not function like conventional transcription factors. To gain insights into DksA function, we identified mutations in dksA that bypassed the requirement for ppGpp by selecting for growth of cells lacking ppGpp on minimal medium without amino acids. We show here that two substitutions in DksA, L15F and N88I, result in higher DksA activity both in vivo and in vitro, primarily by increasing the apparent affinity of DksA for RNA polymerase (RNAP). The mutant DksA proteins suggest potential roles for ppGpp in DksA function, identify potential surfaces on DksA crucial for RNAP binding, and provide tools for future studies to elucidate the mechanism of DksA action.


Asunto(s)
Sustitución de Aminoácidos/genética , Proteínas de Escherichia coli/metabolismo , Escherichia coli/genética , Transcripción Genética , Aminoácidos/metabolismo , Proteínas Portadoras/genética , ARN Polimerasas Dirigidas por ADN/metabolismo , Proteínas de Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica , Guanosina Tetrafosfato/metabolismo , Semivida , Holoenzimas/metabolismo , Modelos Moleculares , Proteínas Mutantes/metabolismo , Mutación/genética , Regiones Promotoras Genéticas/genética , Activación Transcripcional/genética , Operón de ARNr/genética
18.
J Med Chem ; 66(12): 7804-7812, 2023 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-37261887

RESUMEN

T cells expressing chimeric antigen receptors (CAR-T cells) have shown unprecedented clinical responses against hematological malignancies. However, some patients relapse after CAR-T cell therapy due to antigen-negative escape variants. Additionally, CAR-T cell therapies showed limited clinical efficacy in solid tumors with high antigen heterogeneity. To overcome this, we metabolically labeled the glycans on cancer cells to redirect CAR-T cell cytotoxicity regardless of the endogenous antigen expression status of the cancer cells. We found that modifying cancer cells with N-azidoacetylmannosamine and bicyclo[6.1.0]non-4-yne-fluorescein isothiocyanate can elicit selective and durable cytotoxicity of anti-FITC CAR-T cells. Furthermore, we demonstrated that dinitrophenyl-conjugated sialic acid (Sia-DNP) generated DNP-modified glycans on cancer cells in situ that could be effectively targeted by anti-DNP CAR-T cells to eradicate established tumors in xenograft models. Our study illustrates that metabolic glycan labeling using unnatural sugars can be combined with CAR-T cell therapy to provide novel cancer immunotherapy for solid tumors that lack viable target antigens.


Asunto(s)
Receptores Quiméricos de Antígenos , Humanos , Receptores Quiméricos de Antígenos/metabolismo , Recurrencia Local de Neoplasia/etiología , Recurrencia Local de Neoplasia/metabolismo , Linfocitos T/metabolismo , Inmunoterapia Adoptiva/efectos adversos , Inmunoterapia , Ensayos Antitumor por Modelo de Xenoinjerto , Receptores de Antígenos de Linfocitos T
19.
Med Sci Monit ; 18(12): PR19-25, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23197244

RESUMEN

BACKGROUND: We examined the cerebrospinal fluid (CSF) markers of subarachnoid hemorrhage (SAH)-induced and idiopathic normal pressure hydrocephalus (INPH) to investigate the pathophysiology and mechanism of communicating hydrocephalus compared to obstructive hydrocephalus. MATERIAL/METHODS: We obtained CSF samples from 8 INPH, 10 SAH-induced hydrocephalus, and 6 unmatched patients with non-hemorrhagic obstructive hydrocephalus during their ventriculoperitoneal shunt operations. Transforming growth factor (TGF)-ß1, tumor necrosis factor (TNF)-α, vascular endothelial growth factor (VEGF), and total tau in the CSF were analyzed via enzyme-linked immunosorbent assay. RESULTS: The mean VEGF levels in the CSF of patients with SAH-induced hydrocephalus, INPH, and obstructive hydrocephalus were 239 ± 131, 239 ± 75, and 163 ± 122 pg/mL, respectively. The total tau concentrations in the CSF of the groups were 1139 ± 1900, 325 ± 325, and 1550 ± 2886 pg/mL, respectively. TNF-α values were 114 ± 34, 134 ± 38, and 55 ± 16 pg/mL, respectively. TGF-ß1 values were 953 ± 430, 869 ± 447, and 136 ± 63 pg/mL, respectively. A significant difference in TNF-α and TGF-ß1 levels was observed only between SAH-induced and chronic obstructive hydrocephalus, and between INPH and chronic obstructive hydrocephalus (p<0.01). CONCLUSIONS: No significant differences in the 4 CSF biomarker levels were observed between INPH and SAH-induced hydrocephalus, whereas CSF TNF-α and TGF-ß1 levels were increased compared to those in patients with chronic obstructive hydrocephalus. Post-SAH hydrocephalus and INPH are probably more destructive to neural tissues, and then stimulate the inflammatory reaction and healing process, compared with obstructive hydrocephalus.


Asunto(s)
Biomarcadores/líquido cefalorraquídeo , Hidrocéfalo Normotenso/líquido cefalorraquídeo , Hidrocéfalo Normotenso/etiología , Hemorragia Subaracnoidea/líquido cefalorraquídeo , Hemorragia Subaracnoidea/complicaciones , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Enfermedad Crónica , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Factor de Crecimiento Transformador beta1/líquido cefalorraquídeo , Factor de Necrosis Tumoral alfa/líquido cefalorraquídeo , Factor A de Crecimiento Endotelial Vascular/líquido cefalorraquídeo , Proteínas tau/líquido cefalorraquídeo
20.
Artículo en Inglés | MEDLINE | ID: mdl-35564434

RESUMEN

The maxillary sinus growth is initiated 3 months after birth, and it grows lateral and inferior until the pneumatization of the alveolar bone occurs. The facial skeleton has recently been determined as affecting the maxillary sinus, prompting additional studies on changes in the size of the maxillary sinus. This study aimed to determine the size of the maxillary sinus using a 3D program after categorizing South Korean adults according to their facial index (FI) classification. The participants of this study were 60 patients in their 20s, who visited the orthodontic department of Dankook University Dental Hospital (approval no. DUDH IRB 2015-12-022). The CBCT of the patients were extracted and measured as 3D images using Mimics (version 22.0, Materialise, Leuven, Belgium). Upon categorizing the subjects based on their FI classification, they were grouped into the mesoprosopic, leptoprosopic, and hyperleptoprosopic types. A one-way ANOVA was performed to evaluate the mean differences of the maxillary sinus, depending on the FI classification. In this study, the maxillary sinus tended to be wider in those with mesoprosopic type, and tended to be higher in the hyperleptoprosopic type, suggesting a need for clinicians to focus to the shape of the face during clinical treatments.


Asunto(s)
Seno Maxilar , Tomografía Computarizada de Haz Cónico Espiral , Adulto , Tomografía Computarizada de Haz Cónico/métodos , Cara , Humanos , Imagenología Tridimensional , Seno Maxilar/diagnóstico por imagen
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