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1.
Cell ; 186(13): 2865-2879.e20, 2023 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-37301196

RESUMEN

Retroelements are the widespread jumping elements considered as major drivers for genome evolution, which can also be repurposed as gene-editing tools. Here, we determine the cryo-EM structures of eukaryotic R2 retrotransposon with ribosomal DNA target and regulatory RNAs. Combined with biochemical and sequencing analysis, we reveal two essential DNA regions, Drr and Dcr, required for recognition and cleavage. The association of 3' regulatory RNA with R2 protein accelerates the first-strand cleavage, blocks the second-strand cleavage, and initiates the reverse transcription starting from the 3'-tail. Removing 3' regulatory RNA by reverse transcription allows the association of 5' regulatory RNA and initiates the second-strand cleavage. Taken together, our work explains the DNA recognition and RNA supervised sequential retrotransposition mechanisms by R2 machinery, providing insights into the retrotransposon and application reprogramming.


Asunto(s)
ARN , Retroelementos , ARN/metabolismo , División del ADN , ADN Polimerasa Dirigida por ARN/metabolismo , Transcripción Reversa
2.
Nature ; 630(8016): 484-492, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38811729

RESUMEN

The CRISPR system is an adaptive immune system found in prokaryotes that defends host cells against the invasion of foreign DNA1. As part of the ongoing struggle between phages and the bacterial immune system, the CRISPR system has evolved into various types, each with distinct functionalities2. Type II Cas9 is the most extensively studied of these systems and has diverse subtypes. It remains uncertain whether members of this family can evolve additional mechanisms to counter viral invasions3,4. Here we identify 2,062 complete Cas9 loci, predict the structures of their associated proteins and reveal three structural growth trajectories for type II-C Cas9. We found that novel associated genes (NAGs) tended to be present within the loci of larger II-C Cas9s. Further investigation revealed that CbCas9 from Chryseobacterium species contains a novel ß-REC2 domain, and forms a heterotetrameric complex with an NAG-encoded CRISPR-Cas-system-promoting (pro-CRISPR) protein of II-C Cas9 (PcrIIC1). The CbCas9-PcrIIC1 complex exhibits enhanced DNA binding and cleavage activity, broader compatibility for protospacer adjacent motif sequences, increased tolerance for mismatches and improved anti-phage immunity, compared with stand-alone CbCas9. Overall, our work sheds light on the diversity and 'growth evolutionary' trajectories of II-C Cas9 proteins at the structural level, and identifies many NAGs-such as PcrIIC1, which serves as a pro-CRISPR factor to enhance CRISPR-mediated immunity.


Asunto(s)
Bacterias , Bacteriófagos , Proteína 9 Asociada a CRISPR , Sistemas CRISPR-Cas , Bacterias/virología , Bacterias/genética , Bacterias/inmunología , Bacteriófagos/genética , Bacteriófagos/inmunología , Chryseobacterium/genética , Chryseobacterium/inmunología , Chryseobacterium/virología , Proteína 9 Asociada a CRISPR/química , Proteína 9 Asociada a CRISPR/genética , Proteína 9 Asociada a CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Sistemas CRISPR-Cas/inmunología , División del ADN , Sitios Genéticos/genética , Modelos Moleculares , Dominios Proteicos
3.
Brain ; 147(4): 1231-1246, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-37812817

RESUMEN

Dravet syndrome is an intractable developmental and epileptic encephalopathy caused by de novo variants in SCN1A resulting in haploinsufficiency of the voltage-gated sodium channel Nav1.1. We showed previously that administration of the antisense oligonucleotide STK-001, also called ASO-22, generated using targeted augmentation of nuclear gene output technology to prevent inclusion of the nonsense-mediated decay, or poison, exon 20N in human SCN1A, increased productive Scn1a transcript and Nav1.1 expression and reduced the incidence of electrographic seizures and sudden unexpected death in epilepsy in a mouse model of Dravet syndrome. Here, we investigated the mechanism of action of ASO-84, a surrogate for ASO-22 that also targets splicing of SCN1A exon 20N, in Scn1a+/- Dravet syndrome mouse brain. Scn1a +/- Dravet syndrome and wild-type mice received a single intracerebroventricular injection of antisense oligonucleotide or vehicle at postnatal Day 2. We examined the electrophysiological properties of cortical pyramidal neurons and parvalbumin-positive fast-spiking interneurons in brain slices at postnatal Days 21-25 and measured sodium currents in parvalbumin-positive interneurons acutely dissociated from postnatal Day 21-25 brain slices. We show that, in untreated Dravet syndrome mice, intrinsic cortical pyramidal neuron excitability was unchanged while cortical parvalbumin-positive interneurons showed biphasic excitability with initial hyperexcitability followed by hypoexcitability and depolarization block. Dravet syndrome parvalbumin-positive interneuron sodium current density was decreased compared to wild-type. GABAergic signalling to cortical pyramidal neurons was reduced in Dravet syndrome mice, suggesting decreased GABA release from interneurons. ASO-84 treatment restored action potential firing, sodium current density and GABAergic signalling in Dravet syndrome parvalbumin-positive interneurons. Our work suggests that interneuron excitability is selectively affected by ASO-84. This new work provides critical insights into the mechanism of action of this antisense oligonucleotide and supports the potential of antisense oligonucleotide-mediated upregulation of Nav1.1 as a successful strategy to treat Dravet syndrome.


Asunto(s)
Epilepsias Mioclónicas , Oligonucleótidos Antisentido , Ratones , Animales , Humanos , Oligonucleótidos Antisentido/farmacología , Parvalbúminas/metabolismo , Epilepsias Mioclónicas/genética , Canal de Sodio Activado por Voltaje NAV1.1/genética , Interneuronas/metabolismo , Ácido gamma-Aminobutírico , Modelos Animales de Enfermedad
4.
Mol Psychiatry ; 28(3): 1383-1395, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36481932

RESUMEN

In response to stressful events, the hypothalamic-pituitary-adrenal (HPA) axis is activated, and consequently glucocorticoids are released by the adrenal gland into the blood circulation. A large body of research has illustrated that excessive glucocorticoids in the hippocampus exerts negative feedback regulation of the HPA axis through glucocorticoid receptor (GR), which is critical for the homeostasis of the HPA axis. Maternal prenatal stress causes dysfunction of the HPA axis feedback mechanism in their offspring in adulthood. Here we report that telomerase reverse transcriptase (TERT) gene knockout causes hyperactivity of the HPA axis without hippocampal GR deficiency. We found that the level of TERT in the dentate gyrus (DG) of the hippocampus during the developmental stage determines the responses of the HPA axis to stressful events in adulthood through modulating the excitability of the dentate granular cells (DGCs) rather than the expression of GR. Our study also suggests that the prenatal high level of glucocorticoids exposure-induced hypomethylation at Chr13:73764526 in the first exon of mouse Tert gene accounted for TERT deficiency in the DG and HPA axis abnormality in the adult offspring. This study reveals a novel GR-independent mechanism underlying prenatal stress-associated HPA axis impairment, providing a new angle for understanding the mechanisms for maintaining HPA axis homeostasis.


Asunto(s)
Sistema Hipotálamo-Hipofisario , Receptores de Glucocorticoides , Femenino , Embarazo , Animales , Ratones , Sistema Hipotálamo-Hipofisario/metabolismo , Receptores de Glucocorticoides/metabolismo , Glucocorticoides/metabolismo , Sistema Hipófiso-Suprarrenal/metabolismo , Homeostasis
5.
Zhongguo Zhong Yao Za Zhi ; 49(2): 534-549, 2024 Jan.
Artículo en Zh | MEDLINE | ID: mdl-38403328

RESUMEN

This study aimed to systematically review the efficacy and safety of Bidouyan Oral Liquid in the treatment of rhinosinu-sitis(RS). CNKI, Wanfang, SinoMed, VIP, Cochrane Library, PubMed, EMbase, Web of Science, and Ovid were searched for the randomized controlled trial(RCT) of Bidouyan Oral Liquid for the treatment of RS patients. Moreover, the reference lists and the grey literature were searched manually. Two researchers independently screened the literature and extracted data. The Cochrane collaboration's tool for assessing risk of bias(RoB 2.0) in randomized trial was used to assess the methodological quality of the included stu-dies. Meta-analysis was performed in RevMan 5.3 and Stata 12.0, and the grades of recommendation, assessment, development and evaluation(GRADE) was employed to evaluate the quality of evidence. A total of 54 RCTs(35 with drug combinations and 19 with single drugs) comprising 7 511 patients(3 973 in the observation group and 3 538 in the control group) were included. Meta-analysis showed that Bidouyan Oral Liquid + conventional treatment was superior to conventional treatment alone in increasing the total response rate(RR=1.19, 95%CI[1.15, 1.24], P<0.000 01) and decreasing the Lund-Kennedy scores(MD=-1.94, 95%CI[-2.61,-1.26], P<0.000 01), Lund-Mackay scores(MD=-2.14, 95%CI[-2.98,-1.31], P<0.000 01), and visual analogue scale(VAS) scores(MD_(total VAS scores)=-1.28, 95%CI[-1.56,-1.01], P<0.000 01; MD_(nasal congestion VAS scores)=-0.58, 95%CI[-0.89,-0.27], P=0.000 2; MD_(runny nose VAS scores)=-0.61, 95%CI[-0.93,-0.29], P=0.000 2; MD_(olfactory dysfunction VAS scores)=-0.43, 95%CI[-0.52,-0.34], P<0.000 01; MD_(head and facial pain VAS scores)=-0.41, 95%CI[-0.57,-0.26], P<0.000 01). Furthermore, the combined treatment outperformed conventional treatment alone in improving the mucociliary transport rate(MTR)(MD=1.64, 95%CI[1.08, 2.20], P<0.000 01) and lowering the levels of inflammatory cytokines{tumor necrosis factor-α(TNF-α)(SMD=-1.95, 95%CI[-2.57,-1.33], P<0.000 01), interleukin-6(IL-6)(SMD=-2.64, 95%CI[-4.08,-1.21], P=0.000 3)} in RS patients. In addition, the combined treatment did not increase the incidence of adverse reactions(RR=0.83, 95%CI[0.44, 1.57], P=0.57). Bidouyan Oral Liquid was superior to conventional treatment in increasing total response rate(RR=1.25, 95%CI[1.18, 1.32], P<0.000 01), decreasing the Lund-Kennedy(P<0.01) and Lund-Mackay scores(P<0.05), alleviating major symptoms(P_(total VAS scores)<0.01; P_(nasal congestion VAS scores)<0.01; P_(runny nose VAS scores)<0.01; P_(olfactory dysfunction VAS scores)<0.05; P_(head and facial pain VAS scores)<0.01), and decreasing adverse reactions(P=0.03). The results showed that either Bidouyan Oral Liquid or Bidouyan Oral Liquid + conventional treatment can increase the total response rate, decrease the Lund-Kennedy and Lund-Mackay scores, and mitigate major symptoms. In addition, Bidouyan Oral Liquid + conventional treatment improved MTR and reduced the expression of TNF-α and IL-6 without causing serious adverse events. However, due to the limited methodological quality of the included studies, large-sample and high-quality RCTs are needed to provide evidence support.


Asunto(s)
Medicamentos Herbarios Chinos , Trastornos del Olfato , Rinosinusitis , Humanos , Factor de Necrosis Tumoral alfa , Interleucina-6 , Rinorrea , Dolor Facial/inducido químicamente , Trastornos del Olfato/inducido químicamente , Medicamentos Herbarios Chinos/efectos adversos
6.
BMC Plant Biol ; 22(1): 426, 2022 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-36050636

RESUMEN

Modes of floral presentation in some angiosperms attract flies that eat and/or oviposit on seasonal fruiting bodies of fungi. Mushroom mimesis by orchid flowers has been speculated in the geoflorous, Indo-Malaysian-Australasian, genus Corybas s.l. for decades but most studies remain fragmentary and are often inconclusive. Here we report the roles of fungus gnats as pollinators of Corybas geminigibbus and C. shanlinshiensis in southwestern Yunnan, China, combining results of field observations, lab analyses, and manipulative experiments. Hand pollination experiments suggested both species were self-compatible but incapable of mechanical self-pollination, thereby requiring pollinators for fruit production. A female of a Phthinia sp. (Mycetophilidae) carried a pollinarium of C. geminigibbus dorsally on its thorax. Two females and one male of Exechia sp. (Mycetophilidae) visiting flowers of C. shanlinshiensis carried dorsal depositions of pollinaria on their thoraces. Mycetophilid eggs were not found in the flowers of either species. The comparative fragrance analyses of these flowers and three co-fruiting mushroom species did not suggest that either orchid species was a brood-site mimic. This is the first confirmation of the dispersal of pollinaria of Corybas species by fungus gnats in subtropical-temperate Asia.


Asunto(s)
Orchidaceae , Polinización , Animales , China , Flores , Hongos , Fitomejoramiento
7.
Dig Dis Sci ; 67(7): 2792-2804, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34328590

RESUMEN

BACKGROUND: Studies reported various diagnostic value of radiologic imaging modalities for diagnosis and management of colorectal cancer (CRC). AIMS: To summary the diagnosis and management of CRC using computed tomography colonography (CTC), magnetic resonance colonography (MRC), and positron emission tomography (PET)/computed tomography (CT). METHODS: Comprehensive literature searches were conducted in PubMed, EmBase, and the Cochrane library for studies published before April 2021. The diagnostic performance of CTC, MRC, and PET/CT for CRC was summarized. RESULTS: A total of 54 studies (17 studies for CTC, 8 studies for MRC, and 29 studies for PET/CT) were selected for final analysis. The sensitivity and specificity for CTC ranged from 27 to 100%, 88 to 100%, respectively, and the pooled sensitivity and specificity for CTC were 0.97 (95% CI 0.88-0.99) and 0.99 (95% CI 0.99-1.00). The sensitivity and specificity for MRC ranged from 48 to 100%, 60 to 100%, respectively, and the pooled sensitivity and specificity for MRC were 0.98 (95% C: 0.77-1.00) and 0.94 (95% CI 0.84-0.98). The sensitivity and specificity for PET/CT ranged from 84 to 100%, 33 to 100%, respectively, and the pooled sensitivity and specificity for PET/CT were 0.94 (95% CI 0.92-0.96) and 0.94 (95% CI 0.90-0.97). The area under the receiver operating characteristic curve for CTC, MRC, and PET/CT was 1.00 (95% CI 0.99-1.00), 0.99 (95% CI 0.98-1.00), and 0.97 (0.95% CI 0.95-0.98), respectively. CONCLUSIONS: This study suggested both CTC and MRC with relative higher diagnostic value for diagnosing CRC, while PET/CT with higher diagnostic value in detecting local recurrence for patients with CRC.


Asunto(s)
Colonografía Tomográfica Computarizada , Neoplasias Colorrectales , Colonografía Tomográfica Computarizada/métodos , Neoplasias Colorrectales/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Tomografía de Emisión de Positrones , Tomografía de Emisión de Positrones , Sensibilidad y Especificidad
8.
New Phytol ; 227(4): 1213-1221, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32337728

RESUMEN

In Orchidaceae, pollination is mostly animal-mediated, and one-third of species have evolved a deceptive pollination mechanism without rewards. Cypripedium is a representative lineage of nonrewarding orchids restricted to temperate regions. Cypripedium subtropicum flowers are pollinated by hoverflies and have hairy tufts that visually resemble an aphid colony covered with honey dew. We recorded the behavior of hoverflies on the flowers, determined the breeding system of the species and the structure of hairy tufts, and investigated the roles of hairy tufts and floral volatiles in this specialized pollination by using pollination experiments, scanning electron microscopy, bioassays and chemical analyses. The white hairy tufts covering the sidelobes of the labellum provide edible rewards and serve as crucial visual lures for hoverflies. The flowers emit primarily (E)-ß-farnesene and a smaller amount of ß-pinene that were found to attract hoverflies. Our results suggest that C. subtropicum uses both visual mimicry of an aphid-colonized labellum with a reward and chemical mimicry of aphid alarm pheromones to attract hoverflies for pollination. This is the first described example of a rewarding mimicry system in plants, where the models are animals with their secretions and the reward is similar in nutrients to that of the model mimicked.


Asunto(s)
Áfidos , Orchidaceae , Animales , Flores , Fitomejoramiento , Polinización
9.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(12): 1273-1278, 2020 Dec.
Artículo en Zh | MEDLINE | ID: mdl-33327997

RESUMEN

OBJECTIVE: To study the application of ponderal index (PI), body mass index (BMI), mid-arm circumference/head circumference (MAC/HC), and Clinical Assessment of Nutritional Status (CANS) score in assessing the nutritional status of neonates at birth, and to find a simple and reliable scheme for the assessment of fetal nutritional status. METHODS: PI, BMI, MAC/HC, and CANS were used to assess the nutritional status of full-term infants and preterm infants shortly after birth. The assessment results of these methods were analyzed. RESULTS: Among the 678 full-term infants, 61, 102, 47, and 131 were diagnosed with malnutrition by PI, BMI, MAC/HC, and CANS respectively. Among the 140 preterm infants, 30, 87, 9, and 112 were diagnosed with malnutrition by PI, BMI, MAC/HC, and CANS respectively. The combination of BMI and CANS had a detection rate of 99.3% in full-term infants and 100% in preterm infants. Compared with the single method, the combination significantly improved the detection rate of malnutrition (P < 0.05), while there was no significant difference between the combination of BMI+CANS and the combination of PI+BMI+CANS (P > 0.05). CONCLUSIONS: The combination of BMI+CANS can reduce the rate of missed diagnosis of fetal malnutrition. It is therefore a simple and reliable method for the assessment of fetal malnutrition.


Asunto(s)
Trastornos Nutricionales en el Feto/diagnóstico , Evaluación Nutricional , Índice de Masa Corporal , Humanos , Recién Nacido , Recien Nacido Prematuro , Estado Nutricional
10.
Chemistry ; 25(46): 10907-10912, 2019 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-31304646

RESUMEN

Trifluoromethyl trifluoromethanesulfonate has proved to be an excellent reservoir of difluorophosgene and a promising click ligation for amines in the preparation of urea derivatives, heterocycles, and carbamoyl fluorides under metal- and additive-free conditions. The reactions are rapid, efficient, selective, and versatile, and can be performed in benign solvents, giving products in excellent yields with minimal efforts for purification. The characteristics of the reactions meet the requirements of a click reaction. The use of trifluoromethyl trifluoromethanesulfonate as a click reagent is advantageous over other "CO" sources (e.g., TsOCF3 , PhCO2 CF3 , CsOCF3 , AgOCF3 , and triphosgene) because this reagent is readily accessible; easy to scale up; and highly reactive, even under metal- and additive-free conditions. It is anticipated that CF3 SO3 CF3 will be increasingly as important as SO2 F2 as a click agent in future drug design and development.

11.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3358-3364, 2019 Aug.
Artículo en Zh | MEDLINE | ID: mdl-31602895

RESUMEN

To evaluate the effect of Tripterygium Glycosides Tablets extract in the treatment of rheumatoid arthritis( RA). Clinical trials of treating rheumatoid arthritis with Tripterygium Glycosides Tablets published by Meta-analysis were retrieved from EMbase,PubMed,Clinical Trials,Web of Science,Cochrane Library,CNKI,Wanfang,VIP,CBM and Chi CTR,and comprehensively analyzed. A total of 3 studies were enrolled,the modified Sharp score( m TSS),tender join joint erosions( JE) and joint space narrowing( JSN) of Tripterygium Glycosides Tablets group were significant superior to those of control group,including positive drugs methotrexate( MTX) and salazopyridine( SSZ)( P<0. 01). Tripterygium Glycosides Tablets had an effect in treating RA. Due to the small sample size,this study shall be verified with high-quality,large-sample-size double-blinded RCTs.


Asunto(s)
Antirreumáticos/farmacología , Artritis Reumatoide/tratamiento farmacológico , Glicósidos/farmacología , Tripterygium/química , Humanos , Comprimidos
12.
Biochem Biophys Res Commun ; 493(1): 862-868, 2017 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-28888982

RESUMEN

Granule cells in the dentate gyrus regenerate constantly in adult hippocampus and then integrate into neural circuits in the hippocampus thereby providing the neural basis for learning and memory. Promoting the neurogenesis in the hippocampus facilitates learning and memory such as spatial learning, object identification, and extinction learning. The interaction between neuronal nitric oxide synthase (nNOS) and postsynaptic density protein-95 (PSD-95) is reported to negatively regulate neurogenesis in brain, so we hypothesized that disrupting this interaction might facilitate the neurogenesis in the dentate gyrus (DG) and thus enhance the extinction memory retrieval of fear learning. We found that uncoupling the nNOS-PSD-95 complex in remote contextual fear condition promoted both neuronal proliferation and survival in the DG, contributing to an enhanced retrieval of the extinction memory. Moreover, the nNOS-PSD-95 uncoupling-induced neurogenesis may be mediated by the extracellular signal-regulated kinase (ERK) as the phosphorylation level of ERK1/2 was increased after uncoupling. These findings suggest that the nNOS-PSD-95 complex may serve as a novel target for the treatment of post-traumatic stress disorder (PTSD).


Asunto(s)
Giro Dentado/fisiología , Extinción Psicológica/fisiología , Miedo/fisiología , Guanilato-Quinasas/metabolismo , Proteínas de la Membrana/metabolismo , Recuerdo Mental/fisiología , Óxido Nítrico Sintasa de Tipo I/metabolismo , Animales , Homólogo 4 de la Proteína Discs Large , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Red Nerviosa/fisiología
13.
Rapid Commun Mass Spectrom ; 31(2): 171-178, 2017 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-27794190

RESUMEN

RATIONALE: Mass spectrometry (MS)-based protein identification depends mainly on protein extraction and digestion. Although sodium dodecyl sulfate (SDS) can preclude enzymatic digestion and interfere with MS analysis, it is still the most widely used surfactant in these steps. To overcome these disadvantages, a SDS-compatible proteomic technique for SDS removal prior to MS-based analyses was developed, namely filter-aided sample preparation (FASP). METHODS: Herein, based on the effectiveness of sodium deoxycholate and a detergent removal spin column, we developed a modified FASP (mFASP) method and compared its overall performance, total number of peptides and proteins identified for shotgun proteomic experiments with that of the FASP method. RESULTS: Identification of 4570 ± 392 and 9139 ± 317 peptides and description of 862 ± 46 and 1377 ± 33 protein groups with two or more peptides from the ovarian cancer cell line A2780 was accomplished by FASP and mFASP methods, respectively. The mFASP method (21.2 ± 0.2%) had higher average peptide to protein coverage than FASP method (13.2 ± 0.5%). More hydrophobic peptides were identified by mFASP than by FASP, as indicated by the GRAVY score distribution. CONCLUSIONS: The reported method enables reliable and efficient identification of proteins and peptides in whole-cell extracts containing SDS. The new approach allows for higher throughput (the simultaneous identification of more proteins), a more comprehensive investigation of proteins, and potentially the discovery of new biomarkers. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Fragmentos de Péptidos/análisis , Proteínas/análisis , Proteómica/métodos , Línea Celular Tumoral , Ácido Desoxicólico , Detergentes , Filtración , Humanos , Fragmentos de Péptidos/química , Proteínas/química , Proteoma/análisis , Proteoma/química , Dodecil Sulfato de Sodio , Tripsina
14.
J Antimicrob Chemother ; 71(12): 3495-3505, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27605597

RESUMEN

OBJECTIVE: Daclatasvir (DCV) is a pan-genotypic non-structural protein 5A (NS5A) inhibitor that is approved for treatment of hepatitis C virus (HCV) genotype (GT)1 and GT3 in the USA and GT1, GT3 and GT4 in Europe. We set out to examine the impact of daclatasvir-based regimens on the sustained virologic response (SVR) in patients with GT2 infection with respect to GT2 subtype and NS5A polymorphisms at amino acid positions associated with daclatasvir resistance. METHODS: Analyses were performed on 283 GT2 NS5A sequences from five daclatasvir regimen-based clinical trials (ClinicalTrials.gov: NCT-01257204, NCT-01359644, NCT-02032875, NCT-02032888 and NCT-01616524) and 143 NS5A sequences from the Los Alamos HCV database. Susceptibility analyses of substitutions at amino acid positions associated with daclatasvir resistance and patient-derived NS5A sequences were performed using an in vitro HCV replication assay. RESULTS: Of 13 GT2 subtypes identified from 426 NS5A sequences, the most prevalent were GT2a (32%), GT2b (48%) and GT2c (10%). The most prevalent NS5A polymorphism was L31M (GT2a = 88%; GT2b = 59%; GT2c = 10%). Substitutions identified in 96% of GT2 NS5A sequences exhibited daclatasvir EC50 values ranging from 0.005 to 20 nM when tested in vitro. A similar range in daclatasvir EC50 values was observed for 16 diverse GT2 patient-derived NS5A sequences (EC50 = 0.005-60 nM). Depending on the daclatasvir-based regimen studied (daclatasvir/interferon-based or daclatasvir/sofosbuvir-based), SVR rates ranged from 90% to 100% in GT2 patients with the most prevalent baseline NS5A-L31M polymorphism, compared with from 96% to 100% without this polymorphism. CONCLUSIONS: High SVR rates were achieved in patients infected with GT2 treated with daclatasvir-based regimens irrespective of GT2 subtype or baseline NS5A polymorphisms.


Asunto(s)
Antivirales/uso terapéutico , Hepacivirus/genética , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/virología , Imidazoles/uso terapéutico , Polimorfismo Genético , Proteínas no Estructurales Virales/genética , Sustitución de Aminoácidos , Carbamatos , Ensayos Clínicos como Asunto , Farmacorresistencia Viral , Europa (Continente) , Genotipo , Hepacivirus/clasificación , Hepacivirus/aislamiento & purificación , Humanos , Mutación Missense , Pirrolidinas , Respuesta Virológica Sostenida , Resultado del Tratamiento , Estados Unidos , Valina/análogos & derivados
15.
Phys Chem Chem Phys ; 17(33): 21576-82, 2015 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-26220437

RESUMEN

Today cancer is one of the most life-threatening diseases in the world. The conventional cancer therapies, including surgery, chemo- and radiation therapies, have some disadvantages, such as limited efficiency and significant side effects. It is necessary to develop new therapeutic treatments. Herein, we integrated the targeted photocatalytic and chemotherapy in a multifunctional drug-delivery platform. The aptamer-functionalized ZnO nanoparticles (NPs) were successfully synthesized. The anti-cancer drug was loaded in the aptamer-ZnO NP system. In vitro cell cytotoxicity experiments showed that combined therapy had a higher rate of death of cancer cells compared to that of single photocatalytic or chemotherapy. Furthermore, aptamer-functionalization could greatly increase the accumulation of nanoparticles within cancer cells and lead to better therapeutic effects. The results suggest that aptamer-functionalized semiconductor nanoparticles may have potential in the development of targeted photocatalytic and chemotherapy against cancer.


Asunto(s)
Antineoplásicos/química , Aptámeros de Nucleótidos/química , Portadores de Fármacos/química , Nanopartículas del Metal/química , Óxido de Zinc/química , Antineoplásicos/toxicidad , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Doxorrubicina/toxicidad , Células HEK293 , Humanos , Luz , Células MCF-7 , Silanos/química
16.
Adv Exp Med Biol ; 859: 493-509, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26238066

RESUMEN

Organic voltage-sensitive dyes offer very high spatial and temporal resolution for imaging neuronal function. However these dyes suffer from the drawbacks of non-specificity of cell staining and low accessibility of the dye to some cell types. Further progress in imaging activity is expected from the development of genetically encoded fluorescent sensors of membrane potential. Cell type specificity of expression of these fluorescent protein (FP) voltage sensors can be obtained via several different mechanisms. One is cell type specificity of infection by individual virus subtypes. A second mechanism is specificity of promoter expression in individual cell types. A third, depends on the offspring of transgenic animals with cell type specific expression of cre recombinase mated with an animal that has the DNA for the FP voltage sensor in all of its cells but its expression is dependent on the recombinase activity. Challenges remain. First, the response time constants of many of the new FP voltage sensors are slower (2-10 ms) than those of organic dyes. This results in a relatively small fractional fluorescence change, ΔF/F, for action potentials. Second, the largest signal presently available is only ~40% for a 100 mV depolarization and many of the new probes have signals that are substantially smaller. Large signals are especially important when attempting to detect fast events because the shorter measurement interval results in a relatively small number of detected photons and therefore a relatively large shot noise (see Chap. 1). Another kind of challenge has occurred when attempts were made to transition from one species to another or from one cell type to another or from cell culture to in vivo measurements.Several laboratories have recently described a number of novel FP voltage sensors. Here we attempt to critically review the current status of these developments in terms of signal size, time course, and in vivo function.


Asunto(s)
Potenciales de Acción/fisiología , Colorantes Fluorescentes/metabolismo , Microscopía Fluorescente/métodos , Sondas Moleculares/metabolismo , Neuronas/fisiología , Imagen de Colorante Sensible al Voltaje/métodos , Animales , Colorantes Fluorescentes/química , Expresión Génica , Genes Reporteros , Vectores Genéticos , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Integrasas/genética , Integrasas/metabolismo , Microscopía Fluorescente/instrumentación , Sondas Moleculares/genética , Neuronas/ultraestructura , Regiones Promotoras Genéticas , Sensibilidad y Especificidad , Factores de Tiempo , Virus/genética , Imagen de Colorante Sensible al Voltaje/instrumentación
17.
Curr Probl Cancer ; 49: 101079, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38492281

RESUMEN

BACKGROUND: We aimed to investigate the postoperative prognosis in patients with early-stage laryngeal squamous cell carcinoma (LSCC) in association with the preoperative blood markers and clinicopathological characteristics and to develop nomograms for individual risk prediction. METHODS: The clinical data of 353 patients with confirmed early-stage LSCC between 2009 and 2018 were retrospectively retrieved from the First Affiliated Hospital with Nanjing Medical University. All patients were randomly divided into the training and testing groups in a 7:3 ratio. Univariate and multivariate analyses were performed, followed by the construction of nomograms to predict recurrence-free survival (RFS) and overall survival (OS). Finally, the nomograms were verified internally, and the predictive capability of the nomograms was evaluated and compared with that of tumour T staging. RESULTS: Univariate and multivariate analyses identified platelet counts (PLT), fibrinogen (FIB), and platelet to lymphocyte ratio (PLR) were independent factors for RFS, and FIB, systemic immune-inflammation index (SII), and haemoglobin (HGB) were independent prognostic factors for OS. The nomograms showed higher predictive C-indexes than T staging. Furthermore, decision curve analysis (DCA) revealed that the net benefit of the nomograms' calculation model was superior to that of T staging. CONCLUSIONS: We established and validated nomograms to predict postoperative 1-, 3- and 5-year RFS and OS in patients with early-stage LSCC based on significant blood markers and clinicopathological characteristics. These models might help clinicians make personalized treatment decisions.


Asunto(s)
Neoplasias Laríngeas , Nomogramas , Humanos , Masculino , Femenino , Persona de Mediana Edad , Neoplasias Laríngeas/cirugía , Neoplasias Laríngeas/patología , Neoplasias Laríngeas/sangre , Neoplasias Laríngeas/mortalidad , Estudios Retrospectivos , Pronóstico , Estadificación de Neoplasias , Carcinoma de Células Escamosas de Cabeza y Cuello/cirugía , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Carcinoma de Células Escamosas de Cabeza y Cuello/sangre , Carcinoma de Células Escamosas de Cabeza y Cuello/mortalidad , Anciano , Tasa de Supervivencia , Estudios de Seguimiento , Adulto , Biomarcadores de Tumor/sangre
18.
Int Immunopharmacol ; 134: 112236, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38744174

RESUMEN

Chronic rhinosinusitis (CRS) represents a heterogeneous disorder primarily characterized by the persistent inflammation of the nasal cavity and paranasal sinuses. The subtype known as chronic rhinosinusitis with nasal polyposis (CRSwNP) is distinguished by a significantly elevated recurrence rate and augmented challenges in the management of nasal polyps. The pathogenesis underlying this subtype remains incompletely understood. Macrophages play a crucial role in mediating the immune system's response to inflammatory stimuli. These cells exhibit remarkable plasticity and heterogeneity, differentiating into either the pro-inflammatory M1 phenotype or the anti-inflammatory and reparative M2 phenotype depending on the surrounding microenvironment. In CRSwNP, macrophages demonstrate reduced production of Interleukin 10 (IL-10), compromised phagocytic activity, and decreased autophagy. Dysregulation of pro-resolving mediators may occur during the inflammatory resolution process, which could potentially hinder the adequate functioning of anti-inflammatory macrophages in facilitating resolution. Collectively, these factors may contribute to the prolonged inflammation observed in CRSwNP. Additionally, macrophages may enhance fibrin cross-linking through the release of factor XIII-A (FAXIII), promoting fibrin deposition and plasma protein retention. Macrophages also modulate vascular permeability by releasing Vascular endothelial growth factor (VEGF). Moreover, they may disrupt the balance between Matrix Metalloproteinases (MMPs) and Tissue Inhibitors of Metalloproteinases (TIMPs), which favors extracellular matrix (ECM) degradation, edema formation, and pseudocyst development. Accumulating evidence suggests a close association between macrophage infiltration and CRSwNP; however, the precise mechanisms underlying this relationship warrant further investigation. In different subtypes of CRSwNP, different macrophage phenotypic aggregations trigger different types of inflammatory features. Increasing evidence suggests that macrophage infiltration is closely associated with CRSwNP, but the mechanism and the relationship between macrophage typing and CRSwNP endophenotyping remain to be further explored. This review discusses the role of different types of macrophages in the pathogenesis of different types of CRSwNP and their contribution to polyp formation, in the hope that a better understanding of the role of macrophages in specific CRSwNP will contribute to a precise and individualized understanding of the disease.


Asunto(s)
Macrófagos , Pólipos Nasales , Rinitis , Sinusitis , Humanos , Macrófagos/inmunología , Pólipos Nasales/inmunología , Sinusitis/inmunología , Animales , Rinitis/inmunología , Enfermedad Crónica
19.
Acad Radiol ; 31(1): 46-57, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37331866

RESUMEN

RATIONALE AND OBJECTIVES: This study aims to develop and validate a nomogram integrating clinical-CT and radiomic features for preoperative prediction of microvascular invasion (MVI) in patients with stage I non­small cell lung cancer (NSCLC). MATERIALS AND METHODS: This retrospective study analyzed 188 cases of stage I NSCLC (63 MVI positives and 125 negatives), which were randomly assigned to training (n = 133) and validation cohorts (n = 55) at a ratio of 7:3. Preoperative non-contrast and contrast-enhanced CT (CECT) images were used to analyze computed tomography (CT) features and extract radiomics features. The student's t-test, the Mann-Whitney-U test, the Pearson correlation, the least absolute shrinkage and selection operator, and multivariable logistic analysis were used to select the significant CT and radiomics features. Multivariable logistic regression analysis was performed to build the clinical-CT, radiomics, and integrated models. The predictive performances were evaluated through the receiver operating characteristic curve and compared with the DeLong test. The integrated nomogram was analyzed regarding discrimination, calibration, and clinical significance. RESULTS: The rad-score was developed with one shape and four textural features. The integrated nomogram incorporating radiomics score, spiculation, and the number of tumor-related vessels (TVN) demonstrated better predictive efficacy than the radiomics and clinical-CT models in the training cohort (area under the curve [AUC], 0.893 vs 0.853 and 0.828, and p = 0.043 and 0.027, respectively) and validation cohort (AUC, 0.887 vs 0.878 and 0.786, and p = 0.761 and 0.043, respectively). The nomogram also demonstrated good calibration and clinical usefulness. CONCLUSION: The radiomics nomogram integrating the radiomics with clinical-CT features demonstrated good performance in predicting MVI status in stage I NSCLC. The nomogram may be a useful tool for physicians in improving personalized management of stage I NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Nomogramas , Radiómica , Estudios Retrospectivos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/cirugía , Tomografía Computarizada por Rayos X
20.
World J Diabetes ; 15(3): 502-518, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38591083

RESUMEN

BACKGROUND: Jianpi Gushen Huayu Decoction (JPGS) has been used to clinically treat diabetic nephropathy (DN) for many years. However, the protective mechanism of JPGS in treating DN remains unclear. AIM: To evaluate the therapeutic effects and the possible mechanism of JPGS on DN. METHODS: We first evaluated the therapeutic potential of JPGS on a DN mouse model. We then investigated the effect of JPGS on the renal metabolite levels of DN mice using non-targeted metabolomics. Furthermore, we examined the effects of JPGS on c-Jun N-terminal kinase (JNK)/P38-mediated apoptosis and the inflammatory responses mediated by toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB)/NOD-like receptor family pyrin domain containing 3 (NLRP3). RESULTS: The ameliorative effects of JPGS on DN mice included the alleviation of renal injury and the control of inflammation and oxidative stress. Untargeted metabolomic analysis revealed that JPGS altered the metabolites of the kidneys in DN mice. A total of 51 differential metabolites were screened. Pathway analysis results indicated that nine pathways significantly changed between the control and model groups, while six pathways significantly altered between the model and JPGS groups. Pathways related to cysteine and methionine metabolism; alanine, tryptophan metabolism; aspartate and glutamate metabolism; and riboflavin metabolism were identified as the key pathways through which JPGS affects DN. Further experimental validation showed that JPGS treatment reduced the expression of TLR4/NF-κB/NLRP3 pathways and JNK/P38 pathway-mediated apoptosis related factors. CONCLUSION: JPGS could markedly treat mice with streptozotocin (STZ)-induced DN, which is possibly related to the regulation of several metabolic pathways found in kidneys. Furthermore, JPGS could improve kidney inflammatory responses and ameliorate kidney injuries in DN mice via the TLR4/NF-κB/NLRP3 pathway and inhibit JNK/P38 pathway-mediated apoptosis in DN mice.

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