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1.
Cell ; 179(1): 147-164.e20, 2019 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-31539493

RESUMEN

Long-distance RNA transport enables local protein synthesis at metabolically-active sites distant from the nucleus. This process ensures an appropriate spatial organization of proteins, vital to polarized cells such as neurons. Here, we present a mechanism for RNA transport in which RNA granules "hitchhike" on moving lysosomes. In vitro biophysical modeling, live-cell microscopy, and unbiased proximity labeling proteomics reveal that annexin A11 (ANXA11), an RNA granule-associated phosphoinositide-binding protein, acts as a molecular tether between RNA granules and lysosomes. ANXA11 possesses an N-terminal low complexity domain, facilitating its phase separation into membraneless RNA granules, and a C-terminal membrane binding domain, enabling interactions with lysosomes. RNA granule transport requires ANXA11, and amyotrophic lateral sclerosis (ALS)-associated mutations in ANXA11 impair RNA granule transport by disrupting their interactions with lysosomes. Thus, ANXA11 mediates neuronal RNA transport by tethering RNA granules to actively-transported lysosomes, performing a critical cellular function that is disrupted in ALS.


Asunto(s)
Anexinas/metabolismo , Transporte Axonal/fisiología , Gránulos Citoplasmáticos/metabolismo , Lisosomas/metabolismo , ARN/metabolismo , Esclerosis Amiotrófica Lateral/metabolismo , Animales , Animales Modificados Genéticamente , Anexinas/genética , Axones/metabolismo , Línea Celular Tumoral , Femenino , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Masculino , Mutación , Unión Proteica , Ratas/embriología , Ratas Sprague-Dawley , Transfección , Pez Cebra
3.
Cell ; 161(2): 291-306, 2015 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-25860611

RESUMEN

Cholesterol is dynamically transported among organelles, which is essential for multiple cellular functions. However, the mechanism underlying intracellular cholesterol transport has remained largely unknown. We established an amphotericin B-based assay enabling a genome-wide shRNA screen for delayed LDL-cholesterol transport and identified 341 hits with particular enrichment of peroxisome genes, suggesting a previously unappreciated pathway for cholesterol transport. We show dynamic membrane contacts between peroxisome and lysosome, which are mediated by lysosomal Synaptotagmin VII binding to the lipid PI(4,5)P2 on peroxisomal membrane. LDL-cholesterol enhances such contacts, and cholesterol is transported from lysosome to peroxisome. Disruption of critical peroxisome genes leads to cholesterol accumulation in lysosome. Together, these findings reveal an unexpected role of peroxisome in intracellular cholesterol transport. We further demonstrate massive cholesterol accumulation in human patient cells and mouse model of peroxisomal disorders, suggesting a contribution of abnormal cholesterol accumulation to these diseases.


Asunto(s)
Colesterol/metabolismo , Lisosomas/metabolismo , Peroxisomas/metabolismo , ARN Interferente Pequeño/metabolismo , Transportadoras de Casetes de Unión a ATP/metabolismo , Adrenoleucodistrofia/metabolismo , Anfotericina B/farmacología , Animales , Transporte Biológico , Estudio de Asociación del Genoma Completo , Humanos , Ratones , Trastorno Peroxisomal/metabolismo , Trastorno Peroxisomal/patología , Fosfatidilinositol 4,5-Difosfato/metabolismo , Sinaptotagminas/metabolismo , Pez Cebra
4.
J Am Chem Soc ; 145(24): 13048-13058, 2023 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-37289993

RESUMEN

Two-dimensional (2D) crystal-to-crystal transition is an important method in crystal engineering because of its ability to directly create diverse crystal materials from one crystal. However, steering a 2D single-layer crystal-to-crystal transition on surfaces with high chemo- and stereoselectivity under ultra-high vacuum conditions is a great challenge because the transition is a complex dynamic process. Here, we report a highly chemoselective 2D crystal transition from radialene to cumulene with retention of stereoselectivity on Ag(111) via retro-[2 + 1] cycloaddition of three-membered carbon rings and directly visualize the transition process involving a stepwise epitaxial growth mechanism by the combination of scanning tunneling microscopy and non-contact atomic force microscopy. Using progression annealing, we found that isocyanides on Ag(111) at a low annealing temperature underwent sequential [1 + 1 + 1] cycloaddition and enantioselective molecular recognition based on C-H···Cl hydrogen bonding interactions to form 2D triaza[3]radialene crystals. In contrast, a higher annealing temperature induced the transformation of triaza[3]radialenes to generate trans-diaza[3]cumulenes, which were further assembled into 2D cumulene-based crystals through twofold N-Ag-N coordination and C-H···Cl hydrogen bonding interactions. By combining the observed distinct transient intermediates and density functional theory calculations, we demonstrate that the retro-[2 + 1] cycloaddition reaction proceeds via the ring opening of a three-membered carbon ring, sequential dechlorination/hydrogen passivation, and deisocyanation. Our findings provide new insights into the growth mechanism and dynamics of 2D crystals and have implications for controllable crystal engineering.

5.
Environ Toxicol ; 38(2): 451-459, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36413041

RESUMEN

Diphenyl difluoroketone (EF-24), a synthetic curcumin analog, has enhanced bioavailability over curcumin. EF-24 acts more powerful bioactivity for anti-inflammatory and anti-cancer activity. However, the effects and mechanism of EF-24 on cervical cancer has not been fully investigated. Herein, this study evaluated the effects of EF-24 on TPA-induced cellular migration of cervical cancer. The results showed that EF-24 substantially reduced the cellular migration and cellular invasion of the HeLa and SiHa cells. Moreover, gelatin zymography, western blotting analyses and real-time PCR revealed that EF-24 suppressed Matrix metalloproteinase-9 (MMP-9) activity, protein expression and mRNA levels. Mechanistically, EF-24 inhibited the phosphorylation of the p38 signaling pathway. In conclusion, EF-24 inhibited TPA-induced cellular migration and cellular invasion of cervical cancer cell lines through modulating MMP-9 expression via downregulating signaling p38 pathway and EF-24 may have potential to serve as a chemopreventive agent of cervical cancer.


Asunto(s)
Curcumina , Metaloproteinasa 9 de la Matriz , Neoplasias del Cuello Uterino , Femenino , Humanos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Curcumina/análogos & derivados , Curcumina/farmacología , Metaloproteinasa 9 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/metabolismo , Invasividad Neoplásica , Transducción de Señal , Neoplasias del Cuello Uterino/enzimología , Neoplasias del Cuello Uterino/patología
6.
Biochem Biophys Res Commun ; 625: 75-80, 2022 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-35952610

RESUMEN

Activating primary afferent TRPV1-positive (TRPV1+) fibers in the spinal dorsal horn triggers exaggerated glutamate release and induces acute pain. However, whether the glutamate postsynaptic responses on dorsal horn neurons are regulated by excessive glutamate is unknown, largely due to intrinsic technical difficulties. In the present study, capsaicin, a specific TRPV1 agonist, was used to activate TRPV1+ fibers in the spinal dorsal horn. Combining three-dimensional (3-D) holographic photostimulation and whole-cell recordings on acute spinal cord slices from adult rodents, we found that postsynaptic glutamate responses were attenuated when activating TRPV1+ fibers with capsaicin. Electron microscopy and Western blot studies found that postsynaptic GluA1 (a subtype of ionotropic glutamate receptors) on the postsynaptic membrane was decreased by acute capsaicin treatment. Therefore, postsynaptic glutamate receptor occupancy and/or downmodulation may underlie this postsynaptic attenuation. Our data thus clarify a scenario in which postsynaptic glutamate responses are largely downregulated upon TRPV1+ activation, and this change may contribute to homeostasis in the dorsal horn circuit when "acute pain" occurs.


Asunto(s)
Capsaicina , Ácido Glutámico , Animales , Capsaicina/farmacología , Potenciales Postsinápticos Excitadores , Dolor , Ratas , Ratas Sprague-Dawley , Médula Espinal/metabolismo , Asta Dorsal de la Médula Espinal/metabolismo , Transmisión Sináptica , Canales Catiónicos TRPV/metabolismo
7.
J Org Chem ; 87(14): 9044-9055, 2022 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-35748643

RESUMEN

A versatile synthesis of α-amino bisphosphonates has been achieved through one-pot interrupted Ritter-type reaction under mild conditions. The reactive Ritter intermediate nitrilium is in situ generated by treatment of nitrile with readily accessible Tf2O/HC(OR1)3, which is trapped by phosphite ester to deliver the desired product. This protocol is efficient, scalable, and well compatible with a broad scope of substrates. In addition, plentiful characteristic JP-C couplings including unusual five-bond long-range 5JP-C and 3JP-C across quaternary carbon and hetero (N) atoms were observed in 13C NMR spectra.


Asunto(s)
Difosfonatos , Nitrilos , Carbono/química , Nitrilos/química
8.
Angew Chem Int Ed Engl ; 61(15): e202117714, 2022 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-35179282

RESUMEN

[3]Radialenes are the smallest carbocyclic structures with unusual topologies and cross-conjugated π-electronic structures. Here, we report a novel [1+1+1] cycloaddition reaction for the synthesis of aza[3]radialenes on the Ag(111) surface, where the steric hindrance of the chlorine substituents guides the selective and orientational assembling of the isocyanide precursors. By combining scanning tunneling microscopy, non-contact atomic force microscopy, and time-of-flight secondary ion mass spectrometry, we determined the atomic structure of the produced aza[3]radialenes. Furthermore, two reaction pathways including synergistic and stepwise are proposed based on density functional theory calculations, which reveal the role of the chlorine substituents in the activation of the isocyano groups via electrostatic interaction.

9.
J Neurosci ; 40(41): 7837-7854, 2020 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-32958568

RESUMEN

As one of the thalamic midline nuclei, the thalamic paraventricular nucleus (PVT) is considered to be an important signal integration site for many descending and ascending pathways that modulate a variety of behaviors, including feeding, emotions, and drug-seeking. A recent study has demonstrated that the PVT is implicated in the acute visceral pain response, but it is unclear whether the PVT plays a critical role in the central processing of chronic pain. Here, we report that the neurons in the posterior portion of the PVT (pPVT) and their downstream pathway are involved in descending nociceptive facilitation regarding the development of neuropathic pain conditions in male rats. Lesions or inhibition of pPVT neurons alleviated mechanical allodynia induced by spared nerve injury (SNI). The excitability of pPVT-central amygdala (CeA) projection neurons was significantly increased in SNI rats. Importantly, selective optogenetic activation of the pPVT-CeA pathway induced obvious mechanical hypersensitivity in naive rats. In addition, we used rabies virus (RV)-based and cell-type-specific retrograde transsynaptic tracing techniques to define a novel neuronal circuit in which glutamatergic neurons in the vlPAG were the target of the pPVT-CeA descending facilitation pathway. Our data suggest that this pPVTGlu+-CeA-vlPAGGlu+ circuit mediates central mechanisms of descending pain facilitation underlying persistent pain conditions.SIGNIFICANCE STATEMENT Studies have shown that the interactions between the posterior portion of the thalamic paraventricular nucleus (pPVT) and central amygdala (CeA) play a critical role in pain-related emotional regulation. However, most reports have associated this circuit with fear and anxiety behaviors. Here, an integrative approach of behavioral tests, electrophysiology, and immunohistochemistry was used to advance the novel concept that the pPVT-CeA pathway activation facilitates neuropathic pain processing. Using rabies virus (RV)-based and cell-type-specific retrograde transsynaptic tracing techniques, we found that glutamatergic neurons in the vlPAG were the target of the pPVT-CeA pathway. Thus, this study indicates the involvement of a pPVTGlu+-CeA-vlPAGGlu+ pathway in a descending facilitatory mechanism underlying neuropathic pain.


Asunto(s)
Núcleo Amigdalino Central/patología , Núcleos Talámicos de la Línea Media/patología , Vías Nerviosas/patología , Neuralgia/patología , Animales , Conducta Animal , Fenómenos Electrofisiológicos , Hiperalgesia/patología , Procesamiento de Imagen Asistido por Computador , Masculino , Neuralgia/psicología , Neuronas/patología , Nocicepción , Optogenética , Sustancia Gris Periacueductal/patología , Ratas , Ratas Sprague-Dawley
10.
J Am Chem Soc ; 143(33): 12955-12960, 2021 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-34397213

RESUMEN

Ladder phenylenes (LPs) composed of alternating fused benzene and cyclobutadiene rings have been synthesized in solution with a maximum length no longer than five units. Longer polymeric LPs have not been obtained so far because of their poor stability and insolubility. Here, we report the synthesis of linear LP chains on the Au(111) surface via dehalogenative [2+2] cycloaddition, in which the steric hindrance of the methyl groups in the 1,2,4,5-tetrabromo-3,6-dimethylbenzene precursor improves the chemoselectivity as well as the orientation orderliness. By combining scanning tunneling microscopy and noncontact atomic force microscopy, we determined the atomic structure and the electronic properties of the LP chains on the metallic substrate and NaCl/Au(111). The tunneling spectroscopy measurements revealed the charged state of chains on the NaCl layer, and this finding is supported by density functional theory calculations, which predict an indirect bandgap and antiferromagnetism in the polymeric LP chains.

11.
J Org Chem ; 86(23): 16926-16939, 2021 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-34752091

RESUMEN

In this paper, we document the construction of functionalized and fused eight-membered carbocycles by the triflic anhydride-mediated cyclization of 7-enamides. Taking advantage of the high electrophilicity of the nitrilium ion intermediates, generated in situ from secondary N-(2,6-dimethyl)anilides, the nonactivated, trisubstituted alkene-nitrilium cyclization reactions proceeded smoothly to afford nonconjugated ß,γ-enimines (for fused 6/6/8 ring systems), conjugated α,ß-enimines (for 6/5/8), or fused 5/8 ring systems in good yields. When the cyclization reactions were followed by one-pot acidic hydrolysis, the reaction led directly to the corresponding α,ß-enones. For some substrates, the reaction afford an efficient access to pendent cyclic ß,γ-enimines/enones.


Asunto(s)
Alquenos , Ciclización
12.
Yi Chuan ; 43(10): 949-961, 2021 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-34702707

RESUMEN

Short tandem repeat (STR) markers have been widely used in forensic paternity testing and individual identification, but the STR mutation might impact on the forensic result interpretation. Importantly, the STR mutation rate was underestimated due to ignoring the "hidden" mutation phenomenon in most similar studies. Considering this, we use Slooten and Ricciardi's restricted mutation model based on big data to obtain more accurate mutation rates for each marker. In this paper, the mutations of 20 autosomal STRs loci (D3S1358, D1S1656, D13S317, Penta E, D16S539, D18S51, D2S1338, CSF1PO, Penta D, TH01, vWA, D21S11, D6S1043, D7S820, D5S818, TPOX, D8S1179, D12S391, D19S433, and FGA; The restricted model does not include the correction factor of D6S1043, this paper calculates remaining 19 STR loci mutation rates) were investigated in 28,313 (Total: 78,739 individuals) confirmed parentage-testing cases in Chinese Han population. As a result, total 1665 mutations were found in all loci, including 1614 one-steps, 34 two-steps, 8 three-steps, and 9 nonintegral mutations. The loci-specific average mutation rates ranged from 0.00007700 (TPOX) to 0.00459050 (FGA) in trio's and 0.00000000 (TPOX) to 0.00344850 (FGA) in duo's. We analyzed the relationship between mutation rates of the apparent and actual, the trio's and duo's, the paternal and maternal, respectively. The results demonstrated that the actual mutation rates are more than the apparent mostly, and the values of µ1"/µ2"(apparent) are also greater than µ1/µ2 (actual) commonly (µ1", µ1; µ2", µ2 are the mutation rates of one-step and two-step). Therefore, the "hidden" mutations are identified. In addition, the mutations rates of trio's and duo's, the paternal and maternal, exhibit significant difference. Next, those mutation data are used to do a comparison with the studies of other Han populations in China, which present the temporal and regional disparities. Due to the large sample size, some rare mutation events, such as monozygotic (MZ) mutation and "fake four-step mutation", are also reported in this study. In conclusion, the estimation values of actual mutations are obtained based on big data, they can not only provide basic data for the Chinese forensic DNA and population genetics databases, but also have important significance for the development of forensic individual identification, paternity testing and genetics research.


Asunto(s)
Macrodatos , Repeticiones de Microsatélite , Frecuencia de los Genes , Genética de Población , Humanos , Repeticiones de Microsatélite/genética , Mutación , Tasa de Mutación
13.
Angew Chem Int Ed Engl ; 60(20): 11370-11377, 2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-33630356

RESUMEN

Although post-functionalization is extensively used to introduce diverse functional groups into supramolecular polymers (SPs) in solution, post-functionalization of SPs on surfaces still remains unexplored. Here we achieved the on-surface post-functionalization of two SPs derived from 5,10,15-tri-(4-pyridyl)-20-bromophenyl porphyrin (Br-TPyP) via cross-coupling reactions on Au(111). The ladder-shaped, Cu-coordinated SPs preformed from Br-TPyP were functionalized through Heck reaction with 4-vinyl-1,1'-biphenyl. In the absence of Cu, Br-TPyP formed chiral SPs as two enantiomers via self-assembly, which were functionalized via divergent cross-coupling reaction with 4-isocyano-1,1'-biphenyl (ICBP). Surprisingly, this reaction was discovered as an enantioselective on-surface reaction induced by the chirality of SPs. Mechanistic analysis and DFT calculations indicated that after debromination of Br-TPyP and the first addition of ICBP, only one attack direction of ICBP to the chiral SP intermediate is permissive in the second addition step due to the steric hindrance, which guaranteed the high enantioselectivity of the reaction.

14.
J Environ Manage ; 267: 110456, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32421660

RESUMEN

To investigate how the aquatic bacterial community of a stratified reservoir drives the evolution of water parameters, the microbial community structure and network characteristics of bacteria in a stratified reservoir were investigated using Illumina MiSeq sequencing technology. A total of 42 phyla and 689 distinct genera were identified, which showed significant seasonal variation. Additionally, stratified variations in the bacterial community strongly reflected the vertical gradient and seasonal changes in water temperature, dissolved oxygen, and nutrition concentration. Furthermore, principal coordinate analysis indicated that most microorganisms were likely influenced by changes in water stratification conditions, exhibiting significant differences during the stratification period and mixing period based on Adonis, MRPP, and Anosim. Compared to the stratification period, 123 enhanced operational taxonomic units (OTUs; 29%) and 226 depleted OTUs (52%) were identified during the mixing period. Linear discriminant analysis effect size results showed that 15 major genera were enriched in the mixing period and 10 major genera were enriched in the stratification period. Importantly, network analysis revealed that the keystone species belonged to hgcI_clade, CL500-29, Acidibacter, Paucimonas, Flavobacterium, Prochlorothrix, Xanthomonadales, Chloroflexia, Burkholderiales, OPB56, KI89A_clade, Synechococcus, Caulobacter or were unclassified. Redundancy analysis showed that temperature, dissolved oxygen, pH, chlorophyll-α, total phosphorus, nitrate, and ammonia were important factors influencing the water bacterial community and function composition, which were consistent with the results of the Mantel test analysis. Furthermore, random forest analysis showed that temperature, dissolved oxygen, ammonia, and total dissolved phosphorous were the most important variables predicting water bacterial community and function community α- and ß-diversity (P < 0.05). Overall, these results provide insight into the interactions between the microbial community and water quality evolution mechanism in Zhoucun reservoir.


Asunto(s)
Agua Potable , Microbiota , Bacterias , Microbiología del Agua , Calidad del Agua
15.
J Virol ; 92(20)2018 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-30068653

RESUMEN

The clustered regularly interspaced short palindromic repeat (CRISPR)-CRISPR-associated protein 9 (Cas9) gene-editing technology has been used to inactivate viral DNA as a new strategy to eliminate chronic viral infections, including HIV-1. This utility of CRISPR-Cas9 is challenged by the high heterogeneity of HIV-1 sequences, which requires the design of the single guide RNA (sgRNA; utilized by the CRISPR-Cas9 system to recognize the target DNA) to match a specific HIV-1 strain in an HIV patient. One solution to this challenge is to target the viral primer binding site (PBS), which HIV-1 copies from cellular tRNA3Lys in each round of reverse transcription and is thus conserved in almost all HIV-1 strains. In this study, we demonstrate that PBS-targeting sgRNA directs Cas9 to cleave the PBS DNA, which evokes deletions or insertions (indels) and strongly diminishes the production of infectious HIV-1. While HIV-1 escapes from PBS-targeting Cas9/sgRNA, unique resistance mechanisms are observed that are dependent on whether the plus or the minus strand of the PBS DNA is bound by sgRNA. Characterization of these viral escape mechanisms will inform future engineering of Cas9 variants that can more potently and persistently inhibit HIV-1 infection.IMPORTANCE The results of this study demonstrate that the gene-editing complex Cas9/sgRNA can be programmed to target and cleave HIV-1 PBS DNA, and thus, inhibit HIV-1 infection. Given that almost all HIV-1 strains have the same PBS, which is copied from the cellular tRNA3Lys during reverse transcription, PBS-targeting sgRNA can be used to inactivate HIV-1 DNA of different strains. We also discovered that HIV-1 uses different mechanisms to resist Cas9/sgRNAs, depending on whether they target the plus or the minus strand of PBS DNA. These findings allow us to predict that a Cas9 variant that uses the CCA sequence as the protospacer adjacent motif (PAM) should more strongly and persistently suppress HIV-1 replication. Together, these data have identified the PBS as the target DNA of Cas9/sgRNA and have predicted how to improve Cas9/sgRNA to achieve more efficient and sustainable suppression of HIV-1 infection, therefore improving the capacity of Cas9/sgRNA in curing HIV-1 infection.


Asunto(s)
Proteína 9 Asociada a CRISPR/metabolismo , ADN Viral/metabolismo , Edición Génica , VIH-1/genética , ARN Guía de Kinetoplastida/metabolismo , Línea Celular , ADN Viral/genética , Humanos , Mutagénesis Insercional , ARN Guía de Kinetoplastida/genética , Eliminación de Secuencia
16.
Eur Radiol ; 29(9): 4742-4750, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30778717

RESUMEN

OBJECTIVES: The tyrosine kinase inhibitor (TKI)-sensitive mutations of the epidermal growth factor receptor (EGFR) gene is essential in the treatment of lung adenocarcinoma. To overcome the difficulty of EGFR gene test in situations where surgery and biopsy samples are too risky to obtain, we tried a noninvasive imaging method using radiomics features and random forest models. METHODS: Five hundred three lung adenocarcinoma patients who received surgery-based treatment were included in this study. The diagnosis and EGFR gene test were based on resections. TKI-sensitive mutations were found in 60.8% of the patients. CT scans before any invasive operation were gathered and analyzed to extract quantitative radiomics features and build random forest classifiers to identify EGFR mutants from wild types. Clinical features (sex and smoking history) were added to the image-based model. The model was trained on a set of 345 patients and validated on an independent test group (n = 158) using the area under the receiver operating characteristic curve (AUC), sensitivity, and specificity. RESULTS: The performance of the random forest model with 94 radiomics features reached an AUC of 0.802. Its AUC was further improved to 0.828 by adding sex and smoking history. The sensitivity and specificity are 60.6% and 85.1% at the best diagnostic decision point. CONCLUSION: Our results showed that radiomics could not only reflect the genetic differences among tumors but also have diagnostic value and the potential to be a diagnostic tool. KEY POINTS: • Radiomics provides a potential noninvasive method for the prediction of EGFR mutation status. • In situations where surgeries and biopsy are not available, CT image-based radiomics models could help to make treatment decisions. • The accuracy, sensitivity, and specificity still need to be improved before the image-based EGFR identifier could be used in clinics.


Asunto(s)
Adenocarcinoma del Pulmón/diagnóstico por imagen , Adenocarcinoma del Pulmón/genética , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/genética , Mutación , Tomografía Computarizada por Rayos X/métodos , Receptores ErbB/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Estudios Retrospectivos , Sensibilidad y Especificidad
17.
Neurosignals ; 26(1): 43-57, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29554653

RESUMEN

BACKGROUND/AIMS: Spinal dorsal horn (SDH) is one of the most important regions for analgesia produced by endomorphin-2 (EM2), which has a higher affinity and specificity for the µ-opioid receptor (MOR) than morphine. Many studies have focused on substantia gelatinosa (SG, lamina II) neurons to elucidate the cellular basis for its antinociceptive effects. However, the complicated types and local circuits of interneurons in the SG make it difficult to understand the real effects of EM2. Therefore, in the present study, we examined the effects of EM2 on projection neurons (PNs) in lamina I. METHODS: Tracing, immunofluoresence, and immunoelectron methods were used to examine the morphological connections between EM2-immunoreactive (-ir) terminals and PNs. By using in vitro whole cell patch clamp recording technique, we investigated the functional effects of EM2 on PNs. RESULTS: EM2-ir afferent terminals directly contacted PNs projecting to the parabrachial nucleus in lamina I. Their synaptic connections were further confirmed by immunoelectron microscopy, most of which were asymmetric synapses. It was found that EM2 had a strong inhibitory effect on the frequency, but not amplitude, of the spontaneous excitatory postsynaptic current (sEPSC) of the spinoparabrachial PNs in lamina I, which could be reversed by MOR antagonist CTOP. However, their spontaneous inhibitory postsynaptic current (sIPSC) and intrinsic properties were not changed after EM2 application. CONCLUSION: Applying EM2 to the SDH could produce analgesia through inhibiting the activities of the spinoparabrachial PNs in lamina I by reducing presynaptic neurotransmitters release from the primary afferent terminals.

18.
J Virol ; 90(7): 3661-75, 2016 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-26792746

RESUMEN

UNLABELLED: DDX3 belongs to the DEAD box RNA helicase family and is a multifunctional protein affecting the life cycle of a variety of viruses. However, its role in influenza virus infection is unknown. In this study, we explored the potential role of DDX3 in influenza virus life cycle and discovered that DDX3 is an antiviral protein. Since many host proteins affect virus life cycle by interacting with certain components of the viral machinery, we first verified whether DDX3 has any viral interaction partners. Immunoprecipitation studies revealed NS1 and NP as direct interaction partners of DDX3. Stress granules (SGs) are known to be antiviral and do form in influenza virus-infected cells expressing defective NS1 protein. Additionally, a recent study showed that DDX3 is an important SG-nucleating factor. We thus explored whether DDX3 plays a role in influenza virus infection through regulation of SGs. Our results showed that SGs were formed in infected cells upon infection with a mutant influenza virus lacking functional NS1 (del NS1) protein, and DDX3 colocalized with NP in SGs. We further determined that the DDX3 helicase domain did not interact with NS1 and NP; however, it was essential for DDX3 localization in virus-induced SGs. Knockdown of DDX3 resulted in impaired SG formation and led to increased virus titers. Taken together, our results identified DDX3 as an antiviral protein with a role in virus-induced SG formation. IMPORTANCE: DDX3 is a multifunctional RNA helicase and has been reported to be involved in regulating various virus life cycles. However, its function during influenza A virus infection remains unknown. In this study, we demonstrated that DDX3 is capable of interacting with influenza virus NS1 and NP proteins; DDX3 and NP colocalize in the del NS1 virus-induced SGs. Furthermore, knockdown of DDX3 impaired SG formation and led to a decreased virus titer. Thus, we provided evidence that DDX3 is an antiviral protein during influenza virus infection and its antiviral activity is through regulation of SG formation. Our findings provide knowledge about the function of DDX3 in the influenza virus life cycle and information for future work on manipulating the SG pathway and its components to fight influenza virus infection.


Asunto(s)
ARN Helicasas DEAD-box/metabolismo , Interacciones Huésped-Patógeno , Subtipo H1N1 del Virus de la Influenza A/inmunología , Proteínas de Unión al ARN/metabolismo , Proteínas del Núcleo Viral/metabolismo , Proteínas no Estructurales Virales/metabolismo , Animales , Células Cultivadas , Células Epiteliales/inmunología , Células Epiteliales/virología , Inmunoprecipitación , Subtipo H1N1 del Virus de la Influenza A/crecimiento & desarrollo , Proteínas de la Nucleocápside , Unión Proteica , Mapeo de Interacción de Proteínas , Carga Viral
19.
Bioorg Med Chem ; 24(4): 672-80, 2016 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-26752094

RESUMEN

A novel series of 7-aminoalkyl-substituted flavonoid derivatives 5a-5r were designed, synthesized and evaluated as potential cholinesterase inhibitors. The results showed that most of the synthesized compounds exhibited potent acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities at the micromolar range. Compound 2-(naphthalen-1-yl)-7-(8-(pyrrolidin-1-yl)octyloxy)-4H-chromen-4-one (5q) showed the best inhibitory activity (IC50, 0.64µM for AChE and 0.42µM for BChE) which were better than our previously reported compounds and the commercially available cholinergic agent Rivastigmine. The results from a Lineweaver-Burk plot indicated a mixed-type inhibition for compound 5q with AChE and BChE. Furthermore, molecular modeling study showed that 5q targeted both the catalytic active site (CAS) and the peripheral anionic site (PAS) of AChE. Besides, these compounds (5a-5r) did not affect PC12 and HepG2 cell viability at the concentration of 10µM. Consequently, these flavonoid derivatives should be further investigated as multipotent agents for the treatment of Alzheimer's disease.


Asunto(s)
Inhibidores de la Colinesterasa/farmacología , Colinesterasas/metabolismo , Diseño de Fármacos , Flavonoides/farmacología , Animales , Butirilcolinesterasa/metabolismo , Dominio Catalítico/efectos de los fármacos , Supervivencia Celular , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/química , Relación Dosis-Respuesta a Droga , Activación Enzimática/efectos de los fármacos , Flavonoides/síntesis química , Flavonoides/química , Células Hep G2 , Humanos , Modelos Moleculares , Estructura Molecular , Células PC12 , Ratas , Relación Estructura-Actividad
20.
Eur Radiol ; 25(4): 922-31, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25417124

RESUMEN

OBJECTIVE: The objective is to use multidetector computed tomography (MDCT) to differentiate phytobezoar impaction and small-bowel faeces in patients with small-bowel obstruction (SBO). METHODS: We retrospectively reviewed 91 consecutive SBO patients with surgically proven phytobezoars (n = 31) or adhesion with small-bowel faeces (n = 60). Two readers blinded to the diagnosis recorded the following MDCT features: degree of obstruction, transition point, mesenteric fatty stranding, intraperitoneal fluid, air-fluid level, pneumatosis intestinalis, and portal venous gas. MDCT measurements of the food debris length, attenuation, luminal diameter, and wall thickness of the obstructed bowel were also compared. RESULTS: A higher grade of obstruction with an absence of mesenteric fatty stranding and intraperitoneal fluid was more commonly seen in the phytobezoar group than in the small-bowel faeces group (p < 0.01). The food debris length (phytobezoar, 5.7 ± 2.8 cm; small-bowel feces, 20.3 ± 7.9 cm, p < 0.01) and mean attenuation (phytobezoar, -59.6 ± 43.3 Hounsfield units (HU); small-bowel faeces, 8.5 ± 7.7 HU, p <0.01) were significantly different between the two groups. The ROC curve showed that food debris length <9.5 cm and mean attenuation value < -11.75 HU predicted phytobezoar impaction. CONCLUSIONS: MDCT features with measurements of the food debris length and mean attenuation assist the differentiation of phytobezoar impaction and small-bowel faeces. KEY POINTS: • MDCT examination helps to differentiate phytobezoar and small-bowel faeces. • A higher grade of obstruction is commonly associated with phytobezoar impaction. • Mesenteric fatty stranding and intraperitoneal fluid are frequently associated with small-bowel faeces. • Quantitative measurement of the obstructed bowel adds the diagnostic accuracy.


Asunto(s)
Bezoares/diagnóstico por imagen , Heces , Obstrucción Intestinal/diagnóstico por imagen , Intestino Delgado/diagnóstico por imagen , Tomografía Computarizada Multidetector , Bezoares/complicaciones , Medios de Contraste , Femenino , Humanos , Obstrucción Intestinal/etiología , Yohexol , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Intensificación de Imagen Radiográfica , Estudios Retrospectivos
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