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1.
Mol Biol Evol ; 41(7)2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38916488

RESUMEN

Nest building is a vital behavior exhibited during breeding in birds, and is possibly induced by environmental and social cues. Although such behavioral plasticity has been hypothesized to be controlled by adult neuronal plasticity, empirical evidence, especially at the neurogenomic level, remains limited. Here, we aim to uncover the gene regulatory networks that govern avian nest construction and examine whether they are associated with circuit rewiring. We designed an experiment to dissect this complex behavior into components in response to pair bonding and nest material acquisition by manipulating the presence of mates and nest materials in 30 pairs of zebra finches. Whole-transcriptome analysis of 300 samples from five brain regions linked to avian nesting behaviors revealed nesting-associated gene expression enriched with neural rewiring functions, including neurogenesis and neuron projection. The enriched expression was observed in the motor/sensorimotor and social behavior networks of female finches, and in the dopaminergic reward system of males. Female birds exhibited predominant neurotranscriptomic changes to initiate the nesting stage, while males showed major changes after entering this stage, underscoring sex-specific roles in nesting behavior. Notably, major neurotranscriptomic changes occurred during pair bonding, with minor changes during nest material acquisition, emphasizing social interactions in nest construction. We also revealed gene expression associated with reproductive behaviors and tactile sensing for nesting behavior. This study presents novel neurogenomic evidence supporting the hypothesis of adult neural plasticity underlying avian nest-construction behavior. By uncovering the genetic toolkits involved, we offer novel insights into the evolution of animals' innate ability to construct nests.


Asunto(s)
Encéfalo , Pinzones , Redes Reguladoras de Genes , Comportamiento de Nidificación , Animales , Pinzones/genética , Pinzones/fisiología , Encéfalo/metabolismo , Encéfalo/fisiología , Femenino , Masculino , Conducta Social , Transcriptoma
2.
Photochem Photobiol Sci ; 23(5): 987-996, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38662174

RESUMEN

Pycnoporus sanguineus is a fungus of the phylum Basidiomycota that has many applications in traditional medicine, modern pharmaceuticals, and agricultural industries. Light plays an essential role in the metabolism, growth, and development of fungi. This study evaluated the mycelial growth and antioxidant and anti-inflammatory activities in P. sanguineus fermentation broth (PFB) cultured under different wavelengths of LED irradiation or in the dark. Compared to the dark cultures, the dry weight of mycelia in red- and yellow-light cultures decreased by 37 and 35% and the yields of pigments increased by 30.92 ± 2.18 mg and 31.75 ± 3.06 mg, respectively. Compared with the dark culture, the DPPH free radical scavenging ability, ABTS+ free radical scavenging capacity, and reducing power of yellow-light cultures increased significantly, and their total phenolic content peaked at 180.0 ± 8.34 µg/mL. However, the reducing power in blue-light cultures was significantly reduced, though the total phenol content did not vary with that of dark cultures. In LPS- and IFN-γ-stimulated RAW 264.7 cells, nitrite release was significantly reduced in the red and yellow light-irradiated PFB compared with the dark culture. In the dark, yellow-, and green-light cultures, TNF-α production in the inflamed RAW 264.7 cells was inhibited by 62, 46, and 14%, respectively. With red-, blue-, and white-light irradiation, TNF-α production was significantly enhanced. Based on these results, we propose that by adjusting the wavelength of the light source during culture, one can effectively modulate the growth, development, and metabolism of P. sanguineus.


Asunto(s)
Antioxidantes , Luz , Pycnoporus , Ratones , Animales , Antioxidantes/farmacología , Antioxidantes/química , Antioxidantes/metabolismo , Células RAW 264.7 , Pycnoporus/metabolismo , Factores Inmunológicos/farmacología , Factores Inmunológicos/química , Lipopolisacáridos/farmacología , Lipopolisacáridos/antagonistas & inhibidores , Picratos/antagonistas & inhibidores , Picratos/química , Agentes Inmunomoduladores/farmacología , Agentes Inmunomoduladores/química , Compuestos de Bifenilo/antagonistas & inhibidores , Compuestos de Bifenilo/química , Compuestos de Bifenilo/farmacología
3.
Artículo en Inglés | MEDLINE | ID: mdl-38828708

RESUMEN

OBJECTIVE: Biliary atresia (BA) is the leading cause of liver cirrhosis and chronic liver insufficiency in children in the world. Gastroesophageal varices bleeding is an ominous complication of cirrhosis in BA patients and is associated with high morbidity and mortality. In this study, we aimed to investigate the utility of noninvasive Baveno VI and Baveno VII criteria for the screening of varices need treatment (VNT) and the need for liver transplantation in BA patients. METHODS: This study enrolled 48 BA patients (23 females and 25 males) who underwent an esophagogastroduodenoscopy (EGD) and transient elastography at a mean age of 11.18 ± 1.48 years; the clinical data were surveyed in a retrospective design. RESULTS: The sensitivity and negative predictive value of Baveno VI and Baveno VII criteria for the prediction of VNT in BA patients are both 100% and 100%, respectively. The VNT missing rate of Baveno VI and Baveno VII criteria are both 0% in our cohort. The Baveno VI, expanded Baveno VI, and Baveno VII criteria are also predictive of the need for liver transplantation in our cohort (OR = 10.33, 4.24, and 21.33; p = 0.009, 0.03, and 0.007, respectively). CONCLUSION: The Baveno VI and Baveno VII criteria are useful for the screening of VNT and minimize non-necessary invasive EGD in BA patients with low VNT missing rates. The Baveno VI, expanded Baveno VI, and Baveno VII criteria are associated with the need for liver transplantation.

4.
Neuroradiology ; 66(4): 543-556, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38240769

RESUMEN

PURPOSE: We investigated the volumetric changes in the components of the cholinergic pathway for patients with early mild cognitive impairment (EMCI) and those with late mild cognitive impairment (LMCI). The effect of patients' apolipoprotein 4 (APOE-ε4) allele status on the structural changes were analyzed. METHODS: Structural magnetic resonance imaging data were collected. Patients' demographic information, plasma data, and validated global cognitive composite scores were included. Relevant features were extracted for constructing machine learning models to differentiate between EMCI (n = 312) and LMCI (n = 541) and predict patients' neurocognitive function. The data were analyzed primarily through one-way analysis of variance and two-way analysis of covariance. RESULTS: Considerable differences were observed in cholinergic structural changes between patients with EMCI and LMCI. Cholinergic atrophy was more prominent in the LMCI cohort than in the EMCI cohort (P < 0.05 family-wise error corrected). APOE-ε4 differentially affected cholinergic atrophy in the LMCI and EMCI cohorts. For LMCI cohort, APOE-ε4 carriers exhibited increased brain atrophy (left amygdala: P = 0.001; right amygdala: P = 0.006, and right Ch123, P = 0.032). EMCI and LCMI patients showed distinctive associations of gray matter volumes in cholinergic regions with executive (R2 = 0.063 and 0.030 for EMCI and LMCI, respectively) and language (R2 = 0.095 and 0.042 for EMCI and LMCI, respectively) function. CONCLUSIONS: Our data confirmed significant cholinergic atrophy differences between early and late stages of mild cognitive impairment. The impact of the APOE-ε4 allele on cholinergic atrophy varied between the LMCI and EMCI groups.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Disfunción Cognitiva/patología , Imagen por Resonancia Magnética/métodos , Colinérgicos , Apolipoproteínas E , Atrofia , Enfermedad de Alzheimer/patología
5.
Pediatr Res ; 94(3): 1151-1157, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37029238

RESUMEN

BACKGROUND: The prognosis for patients with citrin deficiency is not always benign. This study examined the differences between patients identified early by newborn screening and patients identified later with cholestasis/hepatitis. MATERIALS AND METHODS: This retrospective study included 42 patients with genetically confirmed SLC25A13 mutations who were born between May 1996 and August 2019. Fifteen patients were identified during newborn screening (NBS group) and 27 patients were identified through the onset of cholestasis/hepatitis in infancy (clinical group). RESULTS: Overall, 90% of the patients presented with cholestasis, among whom 86% (31/36) recovered at a median age of 174 days. Compared with patients in the clinical group, patients in the NBS group were significantly younger at diagnosis and at cholestasis-free achievement; they also had significantly lower levels of peak direct bilirubin and liver enzymes. At the median follow-up age of 11.8 years, 21% of the patients had dyslipidemia, whereas 36% of the patients had failure to thrive. The overall mortality rate was 2.4%. Variant c.851_854del was the most frequent, constituting 44% of the mutant alleles. CONCLUSION: Patients identified early by NBS had a better prognosis, demonstrating the importance of a timely diagnosis of NICCD and the need for careful follow-up. IMPACT: Some cases of neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD) are not benign. Compared with patients identified later based on the presence of cholestasis/hepatitis, patients identified early by newborn screening have less severe cholestasis and are cholestasis-free at a significantly younger age. A timely diagnosis is needed, along with follow-up examinations that assess metabolic profile and body weight, to improve the long-term prognosis of NICCD patients.


Asunto(s)
Colestasis Intrahepática , Colestasis , Citrulinemia , Transportadores de Anión Orgánico , Niño , Humanos , Lactante , Recién Nacido , Colestasis/diagnóstico , Colestasis/genética , Colestasis Intrahepática/diagnóstico , Colestasis Intrahepática/genética , Citrulinemia/diagnóstico , Citrulinemia/genética , Citrulinemia/complicaciones , Proteínas de Transporte de Membrana Mitocondrial/genética , Mutación , Transportadores de Anión Orgánico/genética , Estudios Retrospectivos
6.
Eur Radiol ; 33(7): 5097-5106, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36719495

RESUMEN

OBJECTIVE: This study developed a diagnostic tool combining machine learning (ML) segmentation and radiomic texture analysis (RTA) for bone density screening using chest low-dose computed tomography (LDCT). METHODS: A total of 197 patients who underwent LDCT followed by dual-energy X-ray absorptiometry were analyzed. First, an autosegmentation model was trained using LDCT to delineate the thoracic vertebral body (VB). Second, a two-level classifier was developed using radiomic features extracted from VBs for the hierarchical pairwise classification of each patient's bone status. All the patients were initially classified as either normal or abnormal, and all patients with abnormal bone density were then subdivided into an osteopenia group and an osteoporosis group. The performance of the classifier was evaluated through fivefold cross-validation. RESULTS: The model for automated VB segmentation achieved a Sorenson-Dice coefficient of 0.87 ± 0.01. Furthermore, the area under the receiver operating characteristic curve scores for the two-level classifier were 0.96 ± 0.01 for detecting abnormal bone density (accuracy = 0.91 ± 0.02; sensitivity = 0.93 ± 0.03; specificity = 0.89 ± 0.03) and 0.98 ± 0.01 for distinguishing osteoporosis (accuracy = 0.94 ± 0.02; sensitivity = 0.95 ± 0.03; specificity = 0.93 ± 0.03). The testing prediction accuracy levels for the first- and second-level classifiers were 0.92 ± 0.04 and 0.94 ± 0.05, respectively. The overall testing prediction accuracy of our method was 0.90 ± 0.05. CONCLUSION: The combination of ML segmentation and RTA for automated bone density prediction based on LDCT scans is a feasible approach that could be valuable for osteoporosis screening during lung cancer screening. KEY POINTS: • This study developed an automatic diagnostic tool combining machine learning-based segmentation and radiomic texture analysis for bone density screening using chest low-dose computed tomography. • The developed method enables opportunistic screening without quantitative computed tomography or a dedicated phantom. • The developed method could be integrated into the current clinical workflow and used as an adjunct for opportunistic screening or for patients who are ineligible for screening with dual-energy X-ray absorptiometry.


Asunto(s)
Neoplasias Pulmonares , Osteoporosis , Humanos , Detección Precoz del Cáncer , Osteoporosis/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Densidad Ósea , Estudios Retrospectivos
7.
Macromol Rapid Commun ; 44(10): e2200910, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37017474

RESUMEN

This work synthesizes a new bifunctional furan derivative (PDMS-FBZ) through a sequence of hydrosilylation of nadic anhydride (ND) with polydimethylsiloxane (PDMS), reaction of the product with p-aminophenol to form PDMS-ND-OH, and its subsequent Mannich reaction with furfurylamine and CH2 O. Then, the main chain-type copolymer PDMS-DABZ-DDSQ is prepared through a Diels-Alder (DA) cycloaddition of PDMS-FBZ with the bismaleimide-functionalized double-decker silsesquioxane derivative DDSQ-BMI. Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy confirm the structure of this PDMS-DABZ-DDSQ copolymer; differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and dynamic mechanical analysis (DMA) reveal it to have high flexibility and high thermal stability (Tg = 177 °C; Td10 = 441 °C; char yield = 60.1 wt%); contact angle measurements reveal a low surface free energy (18.18 mJ m-2 ) after thermal ring-opening polymerization, because the inorganic PDMS and DDSQ units are dispersed well, as revealed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). This PDMS-DABZ-DDSQ copolymer possesses reversible properties arising from the DA and retro-DA reactions, suggesting its possible application as a functional high-performance material.


Asunto(s)
Benzoxazinas , Polímeros , Reacción de Cicloadición , Benzoxazinas/química , Polímeros/química , Microscopía Electrónica de Rastreo , Dimetilpolisiloxanos
8.
Org Biomol Chem ; 20(20): 4101-4104, 2022 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-35537202

RESUMEN

A selective arylation of donor-acceptor diazo compounds with aniline derivatives catalyzed by Lewis acidic boranes is developed. This simple reaction protocol provides an efficient method for the synthesis of diarylacetates under metal-free conditions.


Asunto(s)
Boranos , Compuestos Azo , Catálisis
9.
J Formos Med Assoc ; 121(2): 510-518, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34266707

RESUMEN

BACKGROUND/PURPOSE: Tissue engineering in dentistry has fundamentally changed the way endodontists assess treatment options. Our previous study found that quercetin-contained mesoporous calcium silicate/calcium sulfate (MSCSQ) could induce hard tissue defect region regeneration. This study focused on whether the MSCSQ scaffold could also be effective in regulating odontogenesis and dentin regeneration. METHODS: In this study, we fabricated MSCSQ composite scaffolds using the 3D printing technique. The characteristics of the MSCSQ scaffold were examined by scanning electron microscope (SEM), and mechanical properties were also assessed. In addition, we evaluated the cell viability, cell proliferation, odontogenic-related protein expression, and mineralization behavior of human dental pulp stem cells (hDPSCs) cultured on different scaffolds. RESULTS: We found the precipitation of spherical-apatite on the scaffold surface rapidly in short periods. The in-vitro results for cell behavior revealed that hDPSCs with an MSCSQ scaffold were significantly higher in cell viability as followed time points. In addition, the specific makers of odontogenesis, such as DSPP and DMP-1 proteins, were induced obviously after culturing the hDPSCs on the MSCSQ scaffold. CONCLUSION: Our results demonstrated that MSCSQ scaffolds could enhance physicochemical and biological behaviors compared to mesoporous calcium silicate/calcium sulfate (MSCS) scaffolds. In addition, MSCSQ scaffolds also enhanced odontogenic and immuno-suppressive properties compared to MSCS scaffolds. These results indicated that MSCSQ scaffolds could be considered a potential bioscaffold for clinical applications and dentin regeneration.


Asunto(s)
Sulfato de Calcio , Andamios del Tejido , Compuestos de Calcio , Caproatos , Diferenciación Celular , Proliferación Celular , Pulpa Dental , Humanos , Lactonas , Odontogénesis , Osteogénesis , Impresión Tridimensional , Silicatos , Sulfatos , Ingeniería de Tejidos
10.
J Formos Med Assoc ; 120(8): 1627-1634, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33593691

RESUMEN

BACKGROUND/PURPOSE: Several growth factors were proven to be effective in the treatment of bone defects and fractures and thus have great potential for bone regeneration applications. However, it needs low-temperature storage and transportation. This study aimed to investigate the herbal extract quercetin, a candidate for natural flavonoid compounds that have been reported to be involved in regulating inflammation and improving immunity and health. METHODS: In this study, we prepared quercetin (Q)/mesoporous calcium silicate calcium sulfate (MSCS)/polycaprolactone (PCL) composite scaffolds using the 3D printing technique, where we immersed it in simulated body fluid (SBF) solution and soaked it for up to 60 days. The characteristics of quercetin scaffold were examined by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), immunofluorescence, and Alizarin Red S staining. RESULTS: We found precipitation of apatite on the surface of the scaffold. The in vitro results for cell proliferation, cytotoxicity, and immunofluorescence staining revealed that Wharton's jelly mesenchymal stem cells (WJMSCs) with a 2% quercetin (Q2) scaffold were significantly higher in number than with 1% quercetin (Q1) and MSCS scaffolds. The phalloidin staining of cell skeletons on the surface of Q2 revealed powerful cell-to-cell adhesion and high expression of green fluorescence. The Q2 scaffold also had the highest calcium deposit levels based on Alizarin Red S staining in all scaffolds. This indicated that quercetin was able to induce cell growth and mitosis, echoing the previous preliminary results. CONCLUSION: Our initial results indicate that this natural herbal extract can be a good bone-based gene substitution for bone regeneration.


Asunto(s)
Células Madre Mesenquimatosas , Osteogénesis , Compuestos de Calcio , Sulfato de Calcio , Caproatos , Proliferación Celular , Lactonas , Impresión Tridimensional , Quercetina , Silicatos , Ingeniería de Tejidos , Andamios del Tejido
11.
J Formos Med Assoc ; 120(1 Pt 3): 651-659, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32741737

RESUMEN

BACKGROUND/PURPOSE: Sjögren's syndrome (SS) is an autoimmune disease and its conventional treatment has exhibited limited therapeutic efficacy. Traditional Chinese medicine has been demonstrated to ameliorate the sicca symptoms of SS by decreasing the level of TH1 and TH2 cytokines and increasing salivary flow rate. A newly designed traditional Chinese medicine, SS-1, showed improved efficacy in alleviating the dryness symptoms of SS patients in the National Taiwan SS cohort investigation. Here, we investigated the effect of SS-1 on T cell responses. METHODS: SS-1 was authenticated and its major compounds were verified by high-performance liquid chromatography. We examined the effects of SS-1 on the activation and TH1, TH2, and TH17 polarization of murine T cells. We also determined the level of TH1, TH2, and TH17 cytokine RNA in peripheral blood mononuclear cells of SS patients before and after SS-1 treatment. RESULTS: SS-1 treatment inhibits the activation and TH1, TH2, and IL-17A+IFNγ+ TH polarization of murine T cells. SS-1 treatment also significantly reduces IFN-γ, IL-4, and IL-13 expression, and moderately reduces IL-17A expression in peripheral blood mononuclear cells of SS patients. CONCLUSION: Our results suggest that SS-1 inhibits T cell activation and diminishes TH1, TH2, and IL-17+IFN-γ+ TH responses in SS patients.


Asunto(s)
Medicamentos Herbarios Chinos , Síndrome de Sjögren , Animales , Humanos , Interferón gamma , Leucocitos Mononucleares , Ratones , Síndrome de Sjögren/tratamiento farmacológico , Linfocitos T , Taiwán
12.
Int J Mol Sci ; 22(17)2021 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-34502160

RESUMEN

Early identification of epidermal growth factor receptor (EGFR) and Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations is crucial for selecting a therapeutic strategy for patients with non-small-cell lung cancer (NSCLC). We proposed a machine learning-based model for feature selection and prediction of EGFR and KRAS mutations in patients with NSCLC by including the least number of the most semantic radiomics features. We included a cohort of 161 patients from 211 patients with NSCLC from The Cancer Imaging Archive (TCIA) and analyzed 161 low-dose computed tomography (LDCT) images for detecting EGFR and KRAS mutations. A total of 851 radiomics features, which were classified into 9 categories, were obtained through manual segmentation and radiomics feature extraction from LDCT. We evaluated our models using a validation set consisting of 18 patients derived from the same TCIA dataset. The results showed that the genetic algorithm plus XGBoost classifier exhibited the most favorable performance, with an accuracy of 0.836 and 0.86 for detecting EGFR and KRAS mutations, respectively. We demonstrated that a noninvasive machine learning-based model including the least number of the most semantic radiomics signatures could robustly predict EGFR and KRAS mutations in patients with NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/genética , Aprendizaje Automático , Mutación , Proteínas Proto-Oncogénicas p21(ras)/genética , Anciano , Anciano de 80 o más Años , Algoritmos , Biomarcadores , Carcinoma de Pulmón de Células no Pequeñas/patología , Receptores ErbB/genética , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Curva ROC , Reproducibilidad de los Resultados , Aprendizaje Automático Supervisado , Tomografía Computarizada por Rayos X
13.
J Biomed Sci ; 27(1): 80, 2020 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-32664906

RESUMEN

BACKGROUND: Recent trials have shown promise in intra-arterial thrombectomy after the first 6-24 h of stroke onset. Quick and precise identification of the salvageable tissue is essential for successful stroke management. In this study, we examined the feasibility of machine learning (ML) approaches for differentiating the ischemic penumbra (IP) from the infarct core (IC) by using diffusion tensor imaging (DTI)-derived metrics. METHODS: Fourteen male rats subjected to permanent middle cerebral artery occlusion (pMCAO) were included in this study. Using a 7 T magnetic resonance imaging, DTI metrics such as fractional anisotropy, pure anisotropy, diffusion magnitude, mean diffusivity (MD), axial diffusivity, and radial diffusivity were derived. The MD and relative cerebral blood flow maps were coregistered to define the IP and IC at 0.5 h after pMCAO. A 2-level classifier was proposed based on DTI-derived metrics to classify stroke hemispheres into the IP, IC, and normal tissue (NT). The classification performance was evaluated using leave-one-out cross validation. RESULTS: The IC and non-IC can be accurately segmented by the proposed 2-level classifier with an area under the receiver operating characteristic curve (AUC) between 0.99 and 1.00, and with accuracies between 96.3 and 96.7%. For the training dataset, the non-IC can be further classified into the IP and NT with an AUC between 0.96 and 0.98, and with accuracies between 95.0 and 95.9%. For the testing dataset, the classification accuracy for IC and non-IC was 96.0 ± 2.3% whereas for IP and NT, it was 80.1 ± 8.0%. Overall, we achieved the accuracy of 88.1 ± 6.7% for classifying three tissue subtypes (IP, IC, and NT) in the stroke hemisphere and the estimated lesion volumes were not significantly different from those of the ground truth (p = .56, .94, and .78, respectively). CONCLUSIONS: Our method achieved comparable results to the conventional approach using perfusion-diffusion mismatch. We suggest that a single DTI sequence along with ML algorithms is capable of dichotomizing ischemic tissue into the IC and IP.


Asunto(s)
Imagen de Difusión Tensora/métodos , Infarto de la Arteria Cerebral Media/patología , Isquemia/diagnóstico por imagen , Aprendizaje Automático/estadística & datos numéricos , Algoritmos , Animales , Benchmarking , Modelos Animales de Enfermedad , Masculino , Curva ROC , Ratas , Ratas Sprague-Dawley
14.
J Biol Chem ; 293(5): 1850-1864, 2018 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-29222330

RESUMEN

Soluble guanylyl cyclase (sGC) is the receptor for nitric oxide and a highly sought-after therapeutic target for the management of cardiovascular diseases. New compounds that stimulate sGC show clinical promise, but where these stimulator compounds bind and how they function remains unknown. Here, using a photolyzable diazirine derivative of a novel stimulator compound, IWP-051, and MS analysis, we localized drug binding to the ß1 heme domain of sGC proteins from the hawkmoth Manduca sexta and from human. Covalent attachments to the stimulator were also identified in bacterial homologs of the sGC heme domain, referred to as H-NOX domains, including those from Nostoc sp. PCC 7120, Shewanella oneidensis, Shewanella woodyi, and Clostridium botulinum, indicating that the binding site is highly conserved. The identification of photoaffinity-labeled peptides was aided by a signature MS fragmentation pattern of general applicability for unequivocal identification of covalently attached compounds. Using NMR, we also examined stimulator binding to sGC from M. sexta and bacterial H-NOX homologs. These data indicated that stimulators bind to a conserved cleft between two subdomains in the sGC heme domain. L12W/T48W substitutions within the binding pocket resulted in a 9-fold decrease in drug response, suggesting that the bulkier tryptophan residues directly block stimulator binding. The localization of stimulator binding to the sGC heme domain reported here resolves the longstanding question of where stimulators bind and provides a path forward for drug discovery.


Asunto(s)
Bacterias/enzimología , Proteínas Bacterianas/química , Hemo/química , Mutación Missense , Guanilil Ciclasa Soluble/química , Sustitución de Aminoácidos , Bacterias/genética , Proteínas Bacterianas/genética , Sitios de Unión , Hemo/genética , Resonancia Magnética Nuclear Biomolecular , Dominios Proteicos , Guanilil Ciclasa Soluble/genética
15.
BMC Med Imaging ; 19(1): 11, 2019 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-30678650

RESUMEN

BACKGROUND: The imaging findings of hypoglycemic encephalopathy can be considerably similar to those of ischemic infarction or toxic leukoencephalopathy. We demonstrated unusual magnetic resonance (MR) imaging features of hypoglycemic encephalopathy which can be confused with other pathology both on imaging and acute clinical presentation. The diffusion-weighted imaging (DWI) and apparent diffusion coefficients (ADC) map findings in our case further supports the hypothesis of hypoglycemia-induced "excitotoxic injury" of glial cells and myelin sheath that might protect neuron axons from intracellular edema and irreversible damage. CASE PRESENTATION: A 72-year-old woman presented with poor appetite and was initially drowsy at home; the symptoms progressed to loss of consciousness accompanied by mild incontinence. The initial glucose level was 44 mg/dL, but no nausea, vomiting, fever, or cold sweating was reported. Physical examination after intravenous glucose supplementation revealed the absence of focal neurological signs, facial palsy, and tongue or eye deviations. The images obtained 24 h after symptoms onset revealed symmetrical hyperintensities on DWI (b-value: 1000) associated with hypointensities on ADC map along the corticospinal tract, from the levels of the cerebral peduncle and the posterior limbs of the internal capsule to the level of the corona radiata, which may mimic the imaging findings of acute ischemic infarction or amyotrophic lateral sclerosis. The patient received sliding-scale insulin therapy and rehabilitation, and she recovered consciousness without motor function deficits after 1 month. Moreover, repeat DWI and ADC map showed the complete disappearance of the lesions. CONCLUSIONS: In the phenomenon of excitotoxic injury, axons could be protected from intracellular edema and irreversible damage, which may explain the reversible clinical symptoms and imaging abnormality after controlling for blood glucose because of the preserved motor axon. The diagnosis of acute symptomatic hypoglycemic encephalopathy through clinical and imaging features can be challenging. It is crucial to differentiate it from ischemic encephalopathy since the management and clinical outcome are different.


Asunto(s)
Encefalopatías/diagnóstico por imagen , Hipoglucemia/complicaciones , Insulina/uso terapéutico , Tractos Piramidales/diagnóstico por imagen , Anciano , Encefalopatías/etiología , Encefalopatías/rehabilitación , Isquemia Encefálica/patología , Diagnóstico Diferencial , Femenino , Humanos , Hipoglucemia/tratamiento farmacológico , Imagen por Resonancia Magnética/métodos , Tractos Piramidales/patología , Accidente Cerebrovascular/patología , Resultado del Tratamiento
16.
BMC Cancer ; 18(1): 799, 2018 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-30089463

RESUMEN

BACKGROUND: Resistance to chemotherapy drugs (e.g. taxol) has been a major obstacle in successful cancer treatment. In A549 human lung adenocarcinoma, acquired resistance to the first-line chemotherapy taxol has been a critical problem in clinics. Sphingolipid (SPL) controls various aspects of cell growth, survival, adhesion, and motility in cancer, and has been gradually regarded as a key factor in drug resistance. To better understand the taxol-resistant mechanism, a comprehensive sphingolipidomic approach was carried out to investigate the sphingolipid metabolism in taxol-resistant strain of A549 cell (A549T). METHODS: A549 and A549T cells were extracted according to the procedure with optimal condition for SPLs. Sphingolipidomic analysis was carried out by using an UHPLC coupled with quadrupole time-of-flight (Q-TOF) MS system for qualitative profiling and an UHPLC coupled with triple quadrupole (QQQ) MS system for quantitative analysis. The differentially expressed sphingolipids between taxol-sensitive and -resistant cells were explored by using multivariate analysis. RESULTS: Based on accurate mass and characteristic fragment ions, 114 SPLs, including 4 new species, were clearly identified. Under the multiple reaction monitoring (MRM) mode of QQQ MS, 75 SPLs were further quantified in both A549 and A549T. Multivariate analysis explored that the levels of 57 sphingolipids significantly altered in A549T comparing to those of A549 (p < 0.001 and VIP > 1), including 35 sphingomyelins (SMs), 14 ceramides (Cers), 3 hexosylceramides (HexCers), 4 lactosylceramides (LacCers) and 1 sphingosine. A significant decrease of SM and Cer levels and overall increase of HexCer and LacCer represent the major SPL metabolic characteristic in A549T. CONCLUSIONS: This study investigated sphingolipid profiles in human lung adenocarcinoma cell lines, which is the most comprehensive sphingolipidomic analysis of A549 and A549T. To some extent, the mechanism of taxol-resistance could be attributed to the aberrant sphingolipid metabolism, "inhibition of the de novo synthesis pathway" and "activation of glycosphingolipid pathway" may play the dominant role for taxol-resistance in A549T. This study provides insights into the strategy for clinical diagnosis and treatment of taxol resistant lung cancer.


Asunto(s)
Células A549 , Resistencia a Antineoplásicos , Neoplasias Pulmonares/metabolismo , Paclitaxel/farmacología , Esfingolípidos , Células A549/química , Células A549/efectos de los fármacos , Células A549/metabolismo , Cromatografía Liquida , Biología Computacional , Humanos , Espectrometría de Masas , Análisis de Componente Principal , Esfingolípidos/análisis , Esfingolípidos/química , Esfingolípidos/metabolismo
17.
Brain Behav Immun ; 73: 562-570, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29959050

RESUMEN

Acute ischemic stroke is followed by a complex interplay between the brain and the immune system in which ischemia-reperfusion leads to a detrimental inflammatory response that causes brain injury. In the brain, IL-15 is expressed by astrocytes, neurons and microglia. Previous study showed that ischemia-reperfusion induces expression of IL-15 by astrocytes. Transgenic over-expression of IL-15 in astrocytes aggravates ischemia-reperfusion brain damage by increasing the levels and promoting the effector functions of CD8+ T and NK cells. Treatment of neonatal rats with IL-15 neutralizing antibody before hypoxia-ischemia induction reduces the infarct volume. However, as stroke-induced inflammatory responses differ between neonate and adult brain, the effects of IL-15 blockade on the injury and immune response arising from stroke in adult animals has remained unclear. In this study, we examined the effect of post-ischemia/reperfusion IL-15 blockade on the pathophysiology of cerebral ischemia-reperfusion in adult mice. Using a cerebral ischemia-reperfusion model, we compared infarct size and the infiltrating immune cells in the brain of wild type (WT) mice and Il15-/- mice lacking NK and memory CD8+ T cells. We also evaluated the effects of IL-15 neutralizing antibody treatment on brain infarct volume, motor function, and the status of brain-infiltrating immune cells in WT mice. Il15-/- mice show a smaller infarct volume and lower numbers of activated brain-infiltrating NK, CD8+ T, and CD4+ T cells compared to WT mice after cerebral ischemia-reperfusion. Post-ischemia/reperfusion IL-15 blockade reduces infarct size and improves motor and locomotor activity. Furthermore, IL-15 blockade reduces the effector function of NK, CD8+ T, and CD4+ T cells in the ischemia-reperfusion brain of WT mice. Ablation of IL-15 responses after cerebral ischemia-reperfusion ameliorates brain injury in adult mice. Therefore, targeting IL-15 is a potential effective therapy for ischemic stroke.


Asunto(s)
Interleucina-15/antagonistas & inhibidores , Daño por Reperfusión/metabolismo , Daño por Reperfusión/prevención & control , Animales , Astrocitos/metabolismo , Encéfalo/metabolismo , Lesiones Encefálicas/metabolismo , Isquemia Encefálica/metabolismo , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/metabolismo , Modelos Animales de Enfermedad , Interleucina-15/metabolismo , Células Asesinas Naturales/metabolismo , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Neuronas/metabolismo , Ratas , Accidente Cerebrovascular/metabolismo , Accidente Cerebrovascular/fisiopatología
18.
Eur Radiol ; 28(11): 4504-4513, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29736847

RESUMEN

OBJECTIVES: To compare diffusion tensor (DT)-derived indices from the thalamic nuclei and cerebrospinal fluid (CSF) hydrodynamic parameters for the prediction of gait responsiveness to the CSF tap test in early iNPH patients. METHODS: In this study, 22 patients with iNPH and 16 normal controls were enrolled with the approval of an institutional review board. DT imaging and phase-contrast magnetic resonance imaging were performed in patients and controls to determine DT-related indices of the sensorimotor-related thalamic nuclei and CSF hydrodynamics. Gait performance was assessed in patients using gait scale before and after the tap test. The Mann-Whitney U test and receiver operating characteristic (ROC) curve analysis were applied to compare group differences between patients and controls and assess the predictive performance of gait responsiveness to the tap test in the patients. RESULTS: Fractional anisotropy (FA) and axial diffusivity showed significant increases in the ventrolateral (VL) and ventroposterolateral (VPL) nuclei of the iNPH group compared with those of the control group (p < 0.05). The predictions of gait responsiveness of ventral thalamic FA alone (area under the ROC curve [AUC] < 0.8) significantly outperformed those of CSF hydrodynamics alone (AUC < 0.6). The AUC curve was elevated to 0.812 when the CSF peak systolic velocity and FA value were combined for the VPL nucleus, yielding the highest sensitivity (0.769) and specificity (0.778) to predict gait responses. CONCLUSIONS: Combined measurements of sensorimotor-related thalamic FA and CSF hydrodynamics can provide potential biomarkers for gait response to the CSF tap test in patients with iNPH. KEY POINTS: • Ventrolateral and ventroposterolateral thalamic FA may predict gait responsiveness to tap test. • Thalamic neuroplasticity can be assessed through DTI in idiopathic normal-pressure hydrocephalus. • Changes in the CST associated with gait control could trigger thalamic neuroplasticity. • Activities of sensorimotor-related circuits could alter in patients with gait disturbance. • Management of patients with iNPH could be more appropriate.


Asunto(s)
Líquido Cefalorraquídeo/fisiología , Marcha/fisiología , Hidrocéfalo Normotenso/fisiopatología , Tálamo/fisiología , Anciano , Anisotropía , Estudios de Casos y Controles , Imagen de Difusión por Resonancia Magnética , Imagen de Difusión Tensora , Femenino , Humanos , Hidrodinámica , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Curva ROC , Sensibilidad y Especificidad
19.
J Gastroenterol Hepatol ; 33(7): 1347-1352, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29266456

RESUMEN

BACKGROUND AND AIM: Acute severe ulcerative colitis (ASUC) is a medical emergency requiring prompt therapeutic intervention. Although infliximab has been used as salvage therapy for over 15 years, clinical predictors of treatment success are lacking. We performed a retrospective analysis to identify factors that predict colectomy and may guide dose intensification. METHODS: Fifty-four hospitalized patients received infliximab for ASUC at seven Australian centers (April 2014-May 2015). Follow-up was over 12 months. The data were primarily analyzed for predictors of colectomy. Accelerated (AI) versus standard (SI) infliximab induction strategies were also compared. RESULTS: Of 54 patients identified, the overall colectomy rate was 15.38% (8/52) at 3 months and 26.92% (14/52) at 12 months. Two patients were lost to follow-up. There was a numerically higher colectomy rate in those treated with AI compared with SI (P = 0.3); however, those treated with AI had more severe biochemical disease. A C-reactive protein (CRP)/albumin ratio cut-off of 0.37 post-commencement of infliximab and before discharge was a significant predictor of colectomy with an area under receiver operating curve of 0.73. Pretreatment CRP and albumin levels were not predictive of colectomy. A Mayo Endoscopic Score of 2 had a 94% PPV for avoidance of colectomy following infliximab salvage. CONCLUSIONS: The baseline Mayo Endoscopic Score and the CRP/albumin ratio following infliximab salvage are significant predictors of treatment response for ASUC and identify patients at high risk of colectomy. Whether this risk can be mitigated using infliximab dose intensification requires prospective evaluation before the CRP/albumin ratio can be integrated into ASUC management algorithms.


Asunto(s)
Colectomía , Colitis Ulcerosa/terapia , Fármacos Gastrointestinales/administración & dosificación , Infliximab/administración & dosificación , Terapia Recuperativa , Enfermedad Aguda , Adulto , Biomarcadores/sangre , Proteína C-Reactiva , Estudios de Cohortes , Colitis Ulcerosa/diagnóstico , Femenino , Estudios de Seguimiento , Predicción , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Estudios Retrospectivos , Riesgo , Albúmina Sérica , Índice de Severidad de la Enfermedad
20.
Nanomedicine ; 14(3): 1019-1031, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29391212

RESUMEN

Non-small-cell lung cancer (NSCLC) is the most common type of lung cancer. Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors are commonly used as the first-line treatment for advanced NSCLC; however, the efficacy of drug delivery remains unknown. Hence, we successfully developed erlotinib-conjugated iron oxide nanoparticles (FeDC-E NPs) as theranostic probe that can potentially provide a new avenue for monitoring drug delivering through noninvasive magnetic resonance imaging. MRI ΔR2* relaxivity measurements offer an opportunity to quantitatively evaluate the uptake of FeDC-E NPs at cellular and tumoral levels. Additionally, NF-κB reporter gene system provides NF-κB activation status monitoring to validate the therapeutic efficiency of FeDC-E NPs. FeDC-E NPs not only inhibit the tumor growth and NF-κB-modulated antiapoptotic mechanism but also trigger extrinsic and intrinsic apoptotic pathways. Taken together, dual functional FeDC-E NPs offer diagnostic and therapeutic benefits against lung cancers, indicating that our presented probe could be applied in clinical.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/patología , Sistemas de Liberación de Medicamentos , Clorhidrato de Erlotinib/farmacología , Neoplasias Pulmonares/patología , Imagen por Resonancia Magnética/métodos , Nanopartículas de Magnetita/administración & dosificación , FN-kappa B/metabolismo , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Antineoplásicos/farmacología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Clorhidrato de Erlotinib/administración & dosificación , Clorhidrato de Erlotinib/química , Regulación Neoplásica de la Expresión Génica , Genes Reporteros , Humanos , Procesamiento de Imagen Asistido por Computador , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Nanopartículas de Magnetita/química , Masculino , Ratones , Ratones Endogámicos BALB C , FN-kappa B/genética , Fantasmas de Imagen , Células Tumorales Cultivadas
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