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1.
Nature ; 625(7994): 264-269, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38093009

RESUMEN

Spin nematic is a magnetic analogue of classical liquid crystals, a fourth state of matter exhibiting characteristics of both liquid and solid1,2. Particularly intriguing is a valence-bond spin nematic3-5, in which spins are quantum entangled to form a multipolar order without breaking time-reversal symmetry, but its unambiguous experimental realization remains elusive. Here we establish a spin nematic phase in the square-lattice iridate Sr2IrO4, which approximately realizes a pseudospin one-half Heisenberg antiferromagnet in the strong spin-orbit coupling limit6-9. Upon cooling, the transition into the spin nematic phase at TC ≈ 263 K is marked by a divergence in the static spin quadrupole susceptibility extracted from our Raman spectra and concomitant emergence of a collective mode associated with the spontaneous breaking of rotational symmetries. The quadrupolar order persists in the antiferromagnetic phase below TN ≈ 230 K and becomes directly observable through its interference with the antiferromagnetic order in resonant X-ray diffraction, which allows us to uniquely determine its spatial structure. Further, we find using resonant inelastic X-ray scattering a complete breakdown of coherent magnon excitations at short-wavelength scales, suggesting a many-body quantum entanglement in the antiferromagnetic state10,11. Taken together, our results reveal a quantum order underlying the Néel antiferromagnet that is widely believed to be intimately connected to the mechanism of high-temperature superconductivity12,13.

2.
J Neurosci ; 44(2)2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-37968116

RESUMEN

Reversal learning measures the ability to form flexible associations between choice outcomes with stimuli and actions that precede them. This type of learning is thought to rely on several cortical and subcortical areas, including the highly interconnected orbitofrontal cortex (OFC) and basolateral amygdala (BLA), and is often impaired in various neuropsychiatric and substance use disorders. However, the unique contributions of these regions to stimulus- and action-based reversal learning have not been systematically compared using a chemogenetic approach particularly before and after the first reversal that introduces new uncertainty. Here, we examined the roles of ventrolateral OFC (vlOFC) and BLA during reversal learning. Male and female rats were prepared with inhibitory designer receptors exclusively activated by designer drugs targeting projection neurons in these regions and tested on a series of deterministic and probabilistic reversals during which they learned about stimulus identity or side (left or right) associated with different reward probabilities. Using a counterbalanced within-subject design, we inhibited these regions prior to reversal sessions. We assessed initial and pre-/post-reversal changes in performance to measure learning and adjustments to reversals, respectively. We found that inhibition of the ventrolateral orbitofrontal cortex (vlOFC), but not BLA, eliminated adjustments to stimulus-based reversals. Inhibition of BLA, but not vlOFC, selectively impaired action-based probabilistic reversal learning, leaving deterministic reversal learning intact. vlOFC exhibited a sex-dependent role in early adjustment to action-based reversals, but not in overall learning. These results reveal dissociable roles for BLA and vlOFC in flexible learning and highlight a more crucial role for BLA in learning meaningful changes in the reward environment.


Asunto(s)
Complejo Nuclear Basolateral , Ratas , Masculino , Femenino , Animales , Incertidumbre , Complejo Nuclear Basolateral/fisiología , Ratas Long-Evans , Corteza Prefrontal/fisiología , Aprendizaje Inverso/fisiología
3.
Genomics ; 115(3): 110625, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37068644

RESUMEN

Precise regulation of transcription in gene expression is critical for all aspects of normal organism form, fitness, and function and even minor alterations in the level, location, and timing of gene expression can result in phenotypic variation within and between species including evolutionary innovations and human disease states. Eukaryotic transcription is regulated by a complex interplay of multiple factors working both at a physical and molecular levels influencing this process. In Saccharomyces cerevisiae, the TF with the greatest number of putative regulatory targets is the essential gene Repressor Activator Protein 1 (RAP1). While much is known about the roles of Rap1 in gene regulation and numerous cellular processes, the response of Rap1 target genes to systematic titration of RAP1 expression level remains unknown. To fill this knowledge gap, we used a strain with a tetracycline-titratable promoter replacing wild-type regulatory sequences of RAP1 to systematically reduce the expression level of RAP1 and followed this with RNA sequencing (RNA-seq) to measure genome-wide gene expression responses. Previous research indicated that Rap1 plays a significant regulatory role in particular groups of genes including telomere-proximal genes, homothallic mating (HM) loci, glycolytic genes, DNA repair genes, and ribosomal protein genes; therefore, we focused our analyses on these groups and downstream targets to determine how they respond to reductions in RAP1 expression level. Overall, despite being known as both an activator and as a repressor of its target genes, we found that Rap1 acts as an activator for more target genes than as a repressor. Additionally, we found that Rap1 functions as an activator of ribosomal protein genes and a repressor for HM loci genes consistent with predictions from the literature. Unexpectedly, we found that Rap1 functions as a repressor of glycolytic enzyme genes contrary to prior reports of it having the opposite effect. We also compared the expression of RAP1 to five different genes related to DNA repair pathway and found that decreasing RAP1 downregulated four of those five genes. Finally, we found no effect of RAP1 depletion on telomere-proximal genes despite its functioning to silence telomeric repeat-containing RNAs. Together our results enrich our understanding of this important transcriptional regulator.


Asunto(s)
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Humanos , Saccharomyces cerevisiae/genética , Factor de Transcripción AP-1/genética , Proteínas de Saccharomyces cerevisiae/genética , Complejo Shelterina , Proteínas de Unión a Telómeros/genética , Proteínas de Unión a Telómeros/metabolismo , Proteínas Ribosómicas/genética , Expresión Génica , Regulación Fúngica de la Expresión Génica , Proteínas Fúngicas/genética , Factores de Transcripción/metabolismo
4.
J Synchrotron Radiat ; 30(Pt 3): 643-649, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-36947164

RESUMEN

An endstation for resonant inelastic X-ray scattering (RIXS), dedicated to operations in the hard X-ray regime, has been constructed at the 1C beamline of Pohang Light Source II. At the Ir L3-edge, a total energy resolution of 34.2 meV was achieved, close to the theoretical estimation of 34.0 meV, which considers factors such as the incident energy bandpass, intrinsic analyzer resolution, geometrical broadening of the spectrometer, finite beam-size effect and Johann aberration. The performance of the RIXS instrument is demonstrated by measuring the RIXS spectra of Sr2IrO4. The endstation can be easily reconfigured to measure energy-integrated intensities with very low background for diffuse scattering and diffraction experiments.

5.
Ir Med J ; 115(5): 599, 2022 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-35696289

RESUMEN

Aims To describe readmissions of hospitalised patients with COVID-19, define predictors of readmission and explore the long term outcomes using the SF-12 score compared to patients who were not readmitted and those not hospitalised. Methods A single centre retrospective in North Inner-City Dublin. Recruitment was done through a COVID follow up clinic. Predictors of readmission and SF-12 scores at two timepoints post follow up at median 3 months and 12 months. Results Seventy (45%) participants were admitted, with a median age of 49.5 years (IQR 41.3-56.9), 36(51%) of whom were female. Unscheduled readmissions at ≤30 days in COVID-19 patients were 9(12.9%) and length of stay was four days (IQR 2-5). Readmissions were due to ongoing symptoms(n=9(64.3%)) or new complications(n=5(35.7%)). Mechanical ventilation and having symptoms of nausea and vomiting on index admission were predictive of readmission. (p=0.002). SF-12 scores at one year of readmitted patients were not different to patients who were never admitted at median one year follow up, p=.089. Conclusions Most readmissions were of short duration. Early follow up of patients post MV or who had nausea and vomiting on index admission should be prioritised. Wellbeing of readmitted patients was not different to those never hospitalised, at one year.


Asunto(s)
COVID-19 , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Náusea , Readmisión del Paciente , Estudios Retrospectivos , Factores de Riesgo , Vómitos
6.
Int Endod J ; 54(7): 1142-1154, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33641170

RESUMEN

AIM: To identify odontogenesis-promoting compounds and examine the molecular mechanism underlying enhanced odontoblast differentiation and tooth formation. METHODOLOGY: Five different nymphaeols, nymphaeol B (NB), isonymphaeol B (INB), nymphaeol A (NA), 3'-geranyl-naringenin (GN) and nymphaeol C (NC) were isolated from the fruit of Macaranga tanarius. The cytotoxic effect of nymphaeols on human DPSCs was observed using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The effect of nymphaeols on odontoblast differentiation was analysed with Alizarin Red S staining and odontoblast marker expression was assessed using real-time polymerase chain reaction and Western blot analysis. The molecular mechanism was investigated with Western blot analysis. In order to examine the effect of INB on dentine formation in the developing tooth germ, INB-soaked beads were placed under the tooth bud explants in the collagen gel; thereafter, the tooth bud explant-bead complexes were implanted into the sub-renal capsules for 3 weeks. Tooth root formation was analysed using micro-computed tomography and histological analysis. Data are presented as mean ± standard error (SEM) values of three independent experiments, and results are compared using a two-tailed Student's t-test. The data were considered to have statistical significance when the P-value was less than 0.05. RESULTS: Three of the compounds, NB, INB, and GN, did not exert a cytotoxic effect on human DPSCs. However, INB was most effective in promoting the deposition of calcium minerals in vitro (P < 0.001) and induced the expression of odontogenic marker genes (P < 0.05). Moreover, this compound strongly induced the phosphorylation of mitogen-activated protein (MAP) kinases and protein kinase B (AKT) (P < 0.05). The inhibition of p38 MAP, c-Jun N-terminal kinase (JNK), and AKT substantially suppressed the INB-induced odontoblast differentiation (P < 0.001). In addition, isonymphaeol B significantly induced the formation of dentine and elongation of the tooth root in vivo (P < 0.05). CONCLUSIONS: Prenylflavonoids, including INB, exerted stimulatory effects on odontoblast differentiation and tooth root and dentine formation via the MAP kinase and AKT signalling pathways. These results suggest that nymphaeols could stimulate the repair processes for dentine defects or injuries.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Euphorbiaceae/química , Flavonoides/farmacología , Odontoblastos/efectos de los fármacos , Células Madre/efectos de los fármacos , Células Cultivadas , Pulpa Dental/citología , Humanos , Proteínas Quinasas Activadas por Mitógenos , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Raíz del Diente , Microtomografía por Rayos X
7.
J Urol ; 204(4): 691-700, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32250729

RESUMEN

PURPOSE: Prostate specific antigen has limited performance in detecting prostate cancer. The transcription factor GATA2 is expressed in aggressive prostate cancer. We analyzed the predictive value of urine extracellular vesicle GATA2 mRNA alone and in combination with a multigene panel to improve detection of prostate cancer and high risk disease. MATERIALS AND METHODS: GATA2 mRNA was analyzed in matched extracellular vesicles isolated from urines before and after prostatectomy (16) and paired urine and tissue prostatectomy samples (19). Extracellular vesicle GATA2 mRNA performance to distinguish prostate cancer and high grade disease was tested in training (52) and validation (165) cohorts. The predictive value of a multigene score including GATA2, PCA3 and TMPRSS2-ERG (GAPT-E) was tested in both cohorts. RESULTS: Confirming its prostate origin, urine extracellular vesicle GATA2 mRNA levels decreased significantly after prostatectomy and correlated with prostate cancer tissue GATA2 mRNA levels. In the training and validation cohort GATA2 discriminated prostate cancer (AUC 0.74 and 0.66) and high grade disease (AUC 0.78 and 0.65), respectively. Notably, the GAPT-E score improved discrimination of prostate cancer (AUC 0.84 and 0.72) and high grade cancer (AUC 0.85 and 0.71) in both cohorts when compared with each biomarker alone and PT-E (PCA3 and TMPRSS2-ERG). A GAPT-E score for high grade prostate cancer would avoid 92.1% of unnecessary prostate biopsies, compared to 61.9% when a PT-E score is used. CONCLUSIONS: Urine extracellular vesicle GATA2 mRNA analysis improves the detection of high risk prostate cancer and may reduce the number of unnecessary biopsies.


Asunto(s)
Vesículas Extracelulares/química , Factor de Transcripción GATA2/genética , Próstata/patología , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , ARN Mensajero/análisis , Anciano , Anciano de 80 o más Años , Biopsia , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
8.
Support Care Cancer ; 28(12): 1-12, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32642950

RESUMEN

PURPOSE: Many head and neck cancer patients who receive radiation therapy experience radiation-induced dysgeusia (RID), which has no standard treatment. The only supplement controlled clinical trials have evaluated for the treatment of RID is zinc. However, the results of these and other studies investigating the use of zinc for RID have been inconsistent. To assess the validity of zinc as a treatment for RID, we conducted a systematic literature search and performed a meta-analysis to determine the extent to which zinc affects RID incidence and the degree to which ongoing RID responds to zinc. METHODS: We searched the Ovid MEDLINE, Ovid Embase, PubMed, and Cochrane Library databases to identify studies investigating the use of zinc-based therapy for RID in head and neck cancer patients treated with radiation that were published between January 1, 2003, and November 9, 2017. Using American Society of Clinical Oncology criteria, we selected studies with a high level of evidence for inclusion in the meta-analysis. RESULTS: Of the 32 full-text articles eligible for inclusion, three were included in the final review and meta-analysis. The meta-analysis showed that, compared with placebo, zinc reduces the incidence of RID (risk ratio, 0.72; 95% confidence interval, 0.67-0.92) but does not improve taste acuity more rapidly following radiation therapy (risk ratio, 2.58; 95% confidence interval, 0.97-6.88). CONCLUSION: Our findings indicate that zinc-based therapy reduces the incidence of RID but has a minimal effect on ongoing RID. Our findings also highlight the need for additional evidence-based research on this topic.


Asunto(s)
Disgeusia/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/radioterapia , Traumatismos por Radiación/tratamiento farmacológico , Zinc/uso terapéutico , Estudios de Casos y Controles , Estudios Transversales , Disgeusia/etiología , Humanos , Estudios Longitudinales , Estudios Prospectivos , Traumatismos por Radiación/etiología , Ensayos Clínicos Controlados Aleatorios como Asunto , Zinc/farmacología
9.
Arch Insect Biochem Physiol ; 105(4): e21739, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32929790

RESUMEN

The small brown planthopper, Laodelphax striatellus, is a dangerous pest in rice fields. Although buprofezin has been used to control L. striatellus for more than a decade, the occurrence of buprofezin-resistant L. striatellus has been recently reported. To develop an alternative pest control strategy, comparative transcriptome analysis of buprofezin-treated and nontreated L. striatellus was performed to screen the buprofezin-specific target genes for RNA interference (RNAi) application. Among six genes downregulated in the buprofezin-treated L. striatellus, RNAi-based silencing of the lipophorin precursor, endocuticle structure glycoprotein, and chitin synthase significantly induced the lethality of L. striatellus in a concentration-dependent manner. In addition, a cocktail of double-stranded RNAs against these three genes showed synergistic effects with buprofezin. These results provide RNAi-based effective approaches to control L. striatellus as well as an efficient method to identify novel target genes for RNAi application.


Asunto(s)
Hemípteros/genética , Resistencia a los Insecticidas/genética , ARN Bicatenario/farmacología , Tiadiazinas/farmacología , Animales , Hemípteros/efectos de los fármacos , Insecticidas/farmacología , Interferencia de ARN , Transcriptoma
10.
Clin Radiol ; 75(9): 711.e13-711.e18, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32571521

RESUMEN

AIM: To evaluate whether there is an association between persistently positive plasma Epstein-Barr virus (EBV) DNA and the presence and the change in benign hyperplasia. MATERIALS AND METHODS: One hundred and seventeen participants with positive-plasma EBV-DNA, but without NPC from previous nasopharyngeal carcinoma (NPC) screening, underwent follow-up magnetic resonance imaging (MRI) and plasma EBV-DNA after 2 years. Logistic regression was used to analyse associations between MRI (benign hyperplasia on the follow-up MRI and change from 2 years earlier), and plasma EBV-DNA, smoking, and age. RESULTS: At follow-up, EBV-DNA positivity and smoking were independent parameters for the presence of benign hyperplasia (p=0.027 and 0.023 respectively). Compared with participants in whom EBV-DNA became negative (n=44/117 37.6%), those in whom EBV-DNA remained positive (n=73/117 62.4%) had a greater risk of benign hyperplasia developing (previous MRI normal), being stable or processing (52/73 71.2% versus 18/44 40.9%; p=0.001). CONCLUSION: These results suggest a potential link between benign hyperplasia on MRI and the EBV. As EBV contributes to NPC oncogenesis, future MRI research is warranted to determine if persistent benign hyperplasia is a risk marker for development of NPC.


Asunto(s)
Detección Precoz del Cáncer/métodos , Infecciones por Virus de Epstein-Barr/diagnóstico , Imagen por Resonancia Magnética/métodos , Neoplasias Nasofaríngeas/diagnóstico , Nasofaringe/patología , Adulto , Anciano , ADN Viral/análisis , Infecciones por Virus de Epstein-Barr/virología , Femenino , Herpesvirus Humano 4/genética , Humanos , Hiperplasia/diagnóstico , Masculino , Persona de Mediana Edad , Neoplasias Nasofaríngeas/virología , Nasofaringe/virología , Estudios Prospectivos
11.
Acta Anaesthesiol Scand ; 64(7): 928-935, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32236951

RESUMEN

BACKGROUND: Perioperative goal-directed fluid therapy is used for haemodynamic optimization in high-risk surgeries. Cardiac output monitoring can be performed by a specialized pressure transducer for arterial pulse waveform analysis (S-APWA). No study has assessed whether real-world use of S-APWA is associated with post-operative outcomes; therefore, using a Japanese administrative claims database, we retrospectively investigated whether S-APWA use is associated with in-hospital mortality among patients undergoing high-risk surgery under general anaesthesia. METHODS: Adult patients who underwent high-risk surgery under general anaesthesia and arterial catheterization between 2014 and 2016 were divided into S-APWA and conventional arterial pressure transducer groups, then compared regarding baseline factors and outcomes. Logistic regression analysis was performed to compare in-hospital mortality. Subgroup analyses evaluated S-APWA efficacy and outcomes based on the type of surgery and patients' comorbidity. RESULTS: S-APWA was used in 6859 of 23 655 (29.0%) patients; the crude in-hospital mortality rate was 3.5%. Adjusted analysis showed no significant association between S-APWA use and in-hospital mortality rate (adjusted odds ratio [aOR] = 0.91; 95% confidence interval [CI]: 0.76-1.07; P = .25). S-APWA use was associated with significantly lower in-hospital mortality in patients undergoing vascular surgery (aOR = 0.67; 95% CI: 0.49-0.94), and significantly higher in-hospital mortality in patients undergoing lower limb amputation (aOR = 2.63; 95% CI: 1.32-5.22). S-APWA use and in-hospital mortality were not significantly associated with other subgroups. CONCLUSION: S-APWA use was not associated with in-hospital mortality in the entire study population. However, S-APWA was associated with decreased in-hospital mortality among vascular surgery and increased in-hospital mortality among lower limb amputation.


Asunto(s)
Mortalidad Hospitalaria , Monitoreo Fisiológico/métodos , Atención Perioperativa/métodos , Análisis de la Onda del Pulso/instrumentación , Análisis de la Onda del Pulso/métodos , Procedimientos Quirúrgicos Operativos , Anciano , Presión Arterial/fisiología , Gasto Cardíaco/fisiología , Estudios de Cohortes , Bases de Datos Factuales , Femenino , Fluidoterapia/métodos , Humanos , Japón , Masculino , Estudios Retrospectivos , Riesgo , Transductores
12.
BMC Anesthesiol ; 20(1): 80, 2020 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-32264827

RESUMEN

BACKGROUND: Cerebral venous thrombosis can be a fatal complication of the postpartum period. Pregnancy is known to be a risk factor for thromboembolism in itself. CASE PRESENTATION: A normal spontaneous vaginal delivery was planned for a 20-year-old primigravida patient with patient-controlled epidural analgesia. Next morning, the patient complained of an occipital headache. An epidural blood patch was performed for diagnostic and therapeutic purpose with 10 ml of autologous blood. That night, she had an episode of seizures. Endotracheal intubation was done to secure the airway. She was transferred to an intensive care unit. Brain CT angiography and MRI showed superior sagittal sinus thrombosis with acute infarct and mild subarachnoid haemorrhage. For cerebral venous thrombosis treatment, heparin was injected and for intracranial pressure control, a hypertonic solution was injected. Despite this medical treatment, intracranial pressure continued to rise. The next day, her mental state changed to stupor. Emergency decompressive craniectomy was performed. Her mental state improved rapidly after surgery. A week later, she was transferred to a general ward. Her health recovered and she was discharged. CONCLUSIONS: We experienced postpartum cerebral venous thrombosis misdiagnosed as postdural puncture headache. We hope that this case report would be helpful in situation which a postpartum young woman complains severe headache in spite of management for headache including autologous epidural blood patch.


Asunto(s)
Trombosis Intracraneal/diagnóstico , Cefalea Pospunción de la Duramadre/diagnóstico , Trombosis de la Vena/diagnóstico , Craniectomía Descompresiva/métodos , Errores Diagnósticos , Femenino , Humanos , Trombosis Intracraneal/cirugía , Periodo Posparto , Embarazo , Complicaciones del Embarazo/diagnóstico , Trombosis de la Vena/cirugía , Adulto Joven
13.
Br Poult Sci ; 61(1): 22-25, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31615265

RESUMEN

1. This experiment investigated the influence of chicken PRDX3 on cell proliferation in chick embryo fibroblast cells using PRDX3 knockdown technology.2. A methyl thiazolyl tetrazolium (MTT) assay was performed to assess the effect of chPRDX3 knockdown on fibroblast proliferation. The antioxidant effect was investigated to determine if it directly mediated fibroblast cell proliferation.3. To determine the role of chPRDX3 on cell proliferation, an siRNA mediated knockdown was performed in chick fibroblast cells using an in vitro assay. The proliferation of fibroblast cells transfected with siPRDX3 #3 and siPRDX3 Mix was significantly decreased after 48 h (P < 0.01). In addition, the knockdown of chicken PRDX3 suppressed cell proliferation through an increase in oxidative stress.4. The results demonstrated that chPRDX3 is required for cell proliferation in chicken fibroblast cells. Such findings have important implications for the maintenance of chicken fibroblast cells.


Asunto(s)
Pollos , Peroxiredoxina III , Animales , Proliferación Celular , Embrión de Pollo , Fibroblastos , ARN Interferente Pequeño
14.
Ann Oncol ; 30(6): 977-982, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30912815

RESUMEN

BACKGROUND: Early-stage nasopharyngeal carcinoma (NPC) evades detection when the primary tumor is hidden from view on endoscopic examination. Therefore, in a prospective study of subjects being screened for NPC using plasma Epstein-Barr virus (EBV) DNA, we conducted a study to investigate whether magnetic resonance imaging (MRI) could detect endoscopically occult NPC. PATIENTS AND METHODS: Participants with persistently positive EBV DNA underwent endoscopic examination and biopsy when suspicious for NPC, followed by MRI blinded to the endoscopic findings. Participants with a negative endoscopic examination and positive MRI were recalled for biopsy or surveillance. Diagnostic performance was assessed by calculating sensitivity, specificity and accuracy, based on the histologic confirmation of NPC in the initial study or in a follow-up period of at least two years. RESULTS: Endoscopic examination and MRI were performed on 275 participants, 34 had NPC, 2 had other cancers and 239 without cancer were followed-up for a median of 36 months (24-60 months). Sensitivity, specificity and accuracy were 76.5%, 97.5% and 94.9%, respectively, for endoscopic examination and 91.2%, 97.5% and 96.7%, respectively, for MRI. NPC was detected only by endoscopic examination in 1/34 (2.9%) participants (a participant with stage I disease), and only by MRI in 6/34 (17.6%) participants (stage I = 4, II = 1, III = 1), two of whom had stage I disease and follow-up showing slow growth on MRI but no change on endoscopic examination for 36 months. CONCLUSION: MRI has a complementary role to play in NPC detection and can enable the earlier detection of endoscopically occult NPC.


Asunto(s)
Infecciones por Virus de Epstein-Barr/diagnóstico , Carcinoma Nasofaríngeo/diagnóstico , Neoplasias Nasofaríngeas/diagnóstico , Adulto , ADN Viral/sangre , ADN Viral/genética , Detección Precoz del Cáncer/métodos , Endoscopía/métodos , Infecciones por Virus de Epstein-Barr/sangre , Infecciones por Virus de Epstein-Barr/patología , Infecciones por Virus de Epstein-Barr/virología , Estudios de Seguimiento , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo/diagnóstico por imagen , Carcinoma Nasofaríngeo/cirugía , Carcinoma Nasofaríngeo/virología , Neoplasias Nasofaríngeas/diagnóstico por imagen , Neoplasias Nasofaríngeas/cirugía , Neoplasias Nasofaríngeas/virología , Pronóstico , Estudios Prospectivos , Carga Viral
15.
Mol Psychiatry ; 23(4): 1021-1030, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29565042

RESUMEN

The role of astrocytes in brain plasticity has not been extensively studied compared with that of neurons. Here we adopted integrative translational and reverse-translational approaches to explore the role of an astrocyte-specific major water channel in the brain, aquaporin-4 (AQP4), in brain plasticity and learning. We initially identified the most prevalent genetic variant of AQP4 (single nucleotide polymorphism of rs162008 with C or T variation, which has a minor allele frequency of 0.21) from a human database (n=60 706) and examined its functionality in modulating the expression level of AQP4 in an in vitro luciferase reporter assay. In the following experiments, AQP4 knock-down in mice not only impaired hippocampal volumetric plasticity after exposure to enriched environment but also caused loss of long-term potentiation after theta-burst stimulation. In humans, there was a cross-sectional association of rs162008 with gray matter (GM) volume variation in cortices, including the vicinity of the Perisylvian heteromodal language area (Sample 1, n=650). GM volume variation in these brain regions was positively associated with the semantic verbal fluency. In a prospective follow-up study (Sample 2, n=45), the effects of an intensive 5-week foreign language (English) learning experience on regional GM volume increase were modulated by this AQP4 variant, which was also associated with verbal learning capacity change. We then delineated in mice mechanisms that included AQP4-dependent transient astrocytic volume changes and astrocytic structural elaboration. We believe our study provides the first integrative evidence for a gliogenetic basis that involves AQP4, underlying language-associated brain plasticity.


Asunto(s)
Acuaporina 4/metabolismo , Astrocitos/citología , Desarrollo del Lenguaje , Aprendizaje/fisiología , Neuroglía/citología , Plasticidad Neuronal/fisiología , Adulto , Animales , Acuaporina 4/biosíntesis , Acuaporina 4/genética , Astrocitos/metabolismo , Encéfalo/metabolismo , Estudios Transversales , Modelos Animales de Enfermedad , Femenino , Estudios de Seguimiento , Frecuencia de los Genes , Sustancia Gris/citología , Sustancia Gris/metabolismo , Hipocampo/metabolismo , Humanos , Masculino , Ratones , Ratones Noqueados , Neuroglía/metabolismo , Neuronas/metabolismo , Polimorfismo de Nucleótido Simple , Estudios Prospectivos
16.
Faraday Discuss ; 213(0): 421-451, 2019 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-30426118

RESUMEN

Hardware artificial neural network (ANN) systems with high density synapse array devices can perform massive parallel computing for pattern recognition with low power consumption. To implement a neuromorphic system with on-chip training capability, we need to develop an ideal synapse device with various device requirements, such as scalability, MLC characteristics, low power operation, data retention, and symmetric/linear conductance changes under potentiation/depression modes. Although various devices have been proposed for synapse applications, they have limitations for application in neuromorphic systems. In this paper, we will cover various RRAM synapse devices, such as filamentary switching RRAM (HfOx, TaOx, Cu-CBRAM) and analog RRAM devices, based on interface resistive switching (Pr0.7Ca0.3MnOx and TiOx) and ferroelectric polarization (HfZrOx). By optimizing potentiation/depression conditions, we could improve the conductance linearity and MLC characteristics of filamentary synapse devices. Interface RRAM has better MLC characteristics with limited retention and conductance linearity. By controlling the reactivity of metal electrodes and the oxygen concentration in oxides, we can modulate the synapse characteristics. Metal-Ferroelectric-Insulator-Semiconductor (MFIS) FET devices exhibit good retention characteristics and analog memory characteristics due to polarization. Based on various synapse device characteristics, we have estimated the pattern recognition accuracy of MNIST handwritten digits and CIFAR-10 datasets. We have confirmed that synapse device characteristics directly affect the pattern recognition accuracy of ANNs. In order to simultaneously satisfy all the requirements of synapse devices, it is necessary to develop new technology capable of controlling the movement of oxygen vacancies and metal ions at the atomic scale. Considering the limited synapse characteristics of current 2-terminal RRAM devices, hardware ANNs capable of only off-chip training can be constructed by optimizing the current RRAM devices by limiting the bit number. A 3-terminal synapse device or a device based on a new operation principle should be developed as an alternative for on-chip training applications.


Asunto(s)
Electrónica/instrumentación , Redes Neurales de la Computación , Óxido de Aluminio/química , Computadores , Cobre/química , Conductividad Eléctrica , Diseño de Equipo , Hafnio/química , Óxidos/química , Semiconductores
17.
J Prosthet Dent ; 121(4): 698-702, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30503146

RESUMEN

This clinical report describes the prosthodontic rehabilitation of a 22-year-old woman with a substantial treatment history of Ewing sarcoma of the left maxillary sinus. The patient was diagnosed with Ewing sarcoma at the age of 7 years and went through chemotherapy, radiation, surgical resection, and free-flap reconstruction, initially without prosthodontic rehabilitation. The patient aged 22 years was referred to the oral oncology clinic at The University of Texas MD Anderson Cancer Center for prosthodontic treatment. The patient's prosthetic rehabilitation with dental implants and a definitive maxillary obturator prosthesis is presented in detail.


Asunto(s)
Implantes Dentales , Sarcoma de Ewing , Adulto , Prótesis Dental de Soporte Implantado , Femenino , Humanos , Maxilar , Seno Maxilar , Prostodoncia , Adulto Joven
18.
Int J Obes (Lond) ; 42(9): 1680-1690, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29453464

RESUMEN

BACKGROUND: The prevalence of non-alcoholic fatty liver disease (NAFLD) in children is increasing. This study evaluated the efficacy of a dietitian-led lifestyle modification programme (D-LMP) to reduce NAFLD in obese adolescents. METHODS: Subjects with intra-hepatic triglyceride content (IHTC) equal to or greater than 5% diagnosed by proton-magnetic resonance spectroscopy (1H-MRS) were enroled and randomly assigned to either the D-LMP intervention or conventional paediatrician-led consultation (P-CON) group. Subjects in the P-CON group received usual care consisting of a consultation by a paediatrician with the child and parents every 16 weeks. Intention-to-treat analysis was used for data analysis. RESULTS: Fifty-two subjects were recruited, with 26 in each group. After the initiation phase (at week-16), there was a greater difference in the change in the IHTC and BMI z-score in the D-LMP group (P = 0.029 and <0.001, respectively) and there was a decrease in dietary intake of fat content (P = 0.019). After 52 weeks of the maintenance phase, both groups had reductions of IHTC to 2-3% and there was no intergroup difference in the rate of reduction. During the maintenance phase, parents' involvement was minimal in the D-LMP group, with only three parents accompanying their children to attend the dietitian sessions. In contrast, over 90% of the parents in the P-CON group regularly accompanied their children to attend the consultations suggesting the possibility that regular parental and paediatrician involvement may contribute to increasing awareness on fatty liver complications. Multivariate analysis showed that only reduction in body fat remained as an independent factor associated with remission of NAFLD at the end of both study phases. CONCLUSIONS: A dietitian-led lifestyle modification intervention reduced IHTC, BMI z-score and body fat in obese Chinese adolescents with NAFLD. To sustain the effect of this intervention, regular parental and paediatrician involvement may be important.


Asunto(s)
Promoción de la Salud/métodos , Estilo de Vida , Enfermedad del Hígado Graso no Alcohólico/dietoterapia , Adolescente , China , Femenino , Humanos , Hígado/química , Hígado/diagnóstico por imagen , Masculino , Nutricionistas , Triglicéridos/análisis
19.
J Viral Hepat ; 25(11): 1331-1340, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29851204

RESUMEN

Vesatolimod is an oral agonist of toll-like receptor 7 designed to minimize systemic exposure and side effects. We assessed the safety and efficacy of vesatolimod in viremic chronic hepatitis B (CHB) patients not currently on oral antiviral treatment (OAV) in a phase 2, multicentre, double-blind, randomized, placebo-controlled study. A total of 192 patients stratified by HBeAg status and alanine aminotransferase level were randomized 2:2:2:1 to receive oral vesatolimod (1-, 2- or 4-mg) or placebo once weekly for 12 weeks; tenofovir disoproxil fumarate (300-mg daily) was administered daily for 48 weeks. Efficacy was assessed by quantitative serum HBsAg decline at Week 24 from baseline. In addition to safety assessments, changes in whole-blood interferon-stimulated gene (ISG) transcripts and serum cytokines were explored. Most patients were male (64.1%) and HBeAg-negative (60.9%) at baseline. Among vesatolimod-treated patients, most (60.4%-69.1%) experienced ≥1 treatment-emergent adverse event; the majority were mild or moderate in severity. No clinically meaningful differences in HBsAg changes from baseline were observed between treatment groups. No patients experienced HBsAg loss, while 3 patients experienced HBeAg loss and hepatitis B e-antibody seroconversion at week 48. HBV DNA suppression rates were similar across all treatment arms at Week 24. ISG15 induction was dose-dependent and did not correlate with HBsAg changes. A small proportion of patients exhibited dose-dependent interferon-α induction that correlated with grade of influenza-like adverse events. Overall, vesatolimod is safe and well tolerated in CHB patients. Although consistent dose-dependent pharmacodynamic induction of ISGs was demonstrated, it did not result in clinically significant HBsAg decline.


Asunto(s)
Virus de la Hepatitis B/efectos de los fármacos , Hepatitis B Crónica/tratamiento farmacológico , Pteridinas/administración & dosificación , Pteridinas/farmacología , Adulto , Anciano , Antivirales/administración & dosificación , Antivirales/efectos adversos , Antivirales/farmacología , Citocinas/sangre , Citocinas/inmunología , ADN Viral/sangre , Método Doble Ciego , Quimioterapia Combinada , Femenino , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/sangre , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/sangre , Hepatitis B Crónica/inmunología , Hepatitis B Crónica/virología , Humanos , Interferón-alfa/sangre , Interferón-alfa/inmunología , Masculino , Persona de Mediana Edad , Pteridinas/efectos adversos , Seroconversión , Tenofovir/administración & dosificación , Tenofovir/efectos adversos , Tenofovir/farmacología , Resultado del Tratamiento , Carga Viral/efectos de los fármacos , Adulto Joven
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