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1.
J Neurosci ; 43(26): 4821-4836, 2023 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-37290936

RESUMEN

Relative motion breaks a camouflaged target from a same-textured background, thus eliciting discrimination of a motion-defined object. Ring (R) neurons are critical components in the Drosophila central complex, which has been implicated in multiple visually guided behaviors. Using two-photon calcium imaging with female flies, we demonstrated that a specific population of R neurons that innervate the superior domain of bulb neuropil, termed superior R neurons, encoded a motion-defined bar with high spatial frequency contents. Upstream superior tuberculo-bulbar (TuBu) neurons transmitted visual signals by releasing acetylcholine within synapses connected with superior R neurons. Blocking TuBu or R neurons impaired tracking performance of the bar, which reveals their importance in motion-defined feature encoding. Additionally, the presentation of a low spatial frequency luminance-defined bar evoked consistent excitation in R neurons of the superior bulb, whereas either excited or inhibited responses were evoked in the inferior bulb. The distinct properties of the responses to the two bar stimuli indicate there is a functional division between the bulb subdomains. Moreover, physiological and behavioral tests with restricted lines suggest that R4d neurons play a vital role in tracking motion-defined bars. We conclude that the central complex receives the motion-defined features via a visual pathway from superior TuBu to R neurons and might encode different visual features via distinct response patterns at the population level, thereby driving visually guided behaviors.SIGNIFICANCE STATEMENT Animals could discriminate a motion-defined object that is indistinguishable with a same-textured background until it moves, but little is known about the underlying neural mechanisms. In this study, we identified that R neurons and their upstream partners, TuBu neurons, innervating the superior bulb of Drosophila central brain are involved in the discrimination of high-frequency motion-defined bars. Our study provides new evidence that R neurons receive multiple visual inputs from distinct upstream neurons, indicating a population coding mechanism for the fly central brain to discriminate diverse visual features. These results build progress in unraveling neural substrates for visually guided behaviors.


Asunto(s)
Drosophila , Percepción de Movimiento , Humanos , Animales , Femenino , Vías Visuales/fisiología , Percepción de Movimiento/fisiología , Neuronas/fisiología , Encéfalo/fisiología
2.
Horm Metab Res ; 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38052232

RESUMEN

Anaplastic thyroid carcinoma (ATC) is an aggressive malignancy threatening patients' life quality. Our previous study has demonstrated that inhibition of long non-coding RNA H19 (lncRNA h19; H19) blocks ATC growth and metastasis. The current study aimed to further explore the potential mechanism of H19 in ATC. Expression of H19, miR-454-3p, and BHLHE40 mRNA was measured using RT-qPCR in tissue samples and cell lines. The dual-luciferase reporter assay and Pearson correlation analysis were used to explore the interaction among H19, miR-454-3p, and BHLHE40. The biological process of proliferation, migration, and invasion was determined using loss- or gain-function CCK-8 and Transwell assays. Western blot assay was used to evaluate the changes in protein levels. H19 was elevated in ATC tissues and cell lines. Based on online prediction database results, miR-454-3p might be a target of H19, and BHLHE40 might be a direct target of miR-454-3p. miR-454-3p expression was decreased in ATC and had a negative interaction with H19. BHLHE40 mRNA expression was increased and has a negative correlation with miR-454-3p and a positive correlation with H19. Downregulation of miR-454-3p and upregulation of BHLHE40 could reverse the decreased cellular activities caused by si-H19. Moreover, the silence of H19 modulates BHLHE40 to affect the PI3K/AKT protein levels and apoptotic-related protein levels. The current study provided a potential detailed mechanism of H19 in ATC, and lncRNA H19-miR-454-3p-BHLHE40 interaction may be a new experimental basis for prognosis and targeted therapy for ATC patients.

3.
Dig Dis Sci ; 68(1): 138-146, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35451710

RESUMEN

BACKGROUND AND AIMS: We have previously shown that gabexate mesylate-poloxamer 407 conjugate (GMTI) alleviates traumatic pancreatitis in rats. In this study, we evaluated the therapeutic effect of GMTI on sodium taurocholate-induced severe acute pancreatitis (SAP) in an optimized rat model. METHODS: An SAP rat model was established via microinjection of 3.5% sodium taurocholate and retention in the bile duct for 1 min. SAP rats were administered GMTI via tail vein injection (i.v.) or tail vein injection + intraperitoneal injection (i.v. + i.p.). All rats were sacrificed at 12 h after treatment. Biochemical approach and enzyme-linked immunosorbent assay were performed to measure the serum levels of amylase (AMY), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6). Hematoxylin and eosin staining and TUNEL assay were conducted to examine histopathology and acinar cell apoptosis in the rat pancreas. RESULTS: SAP was successfully induced in all model rats, as evidenced by progressively aggravating SAP symptoms and signs, pancreatic histopathological abnormalities, as well as elevated serum levels of TNF-α, IL-6, and AMY. The mortality rates at 1 h, 6 h, and 12 h were 0%, 0%, and 25%, respectively. GMTI therapy via i.v. or i.v. + i.p. significantly reduced pancreatic wet weights, ascites amounts, pathological scores, and circulating levels of TNF-α and IL-6 while promoting acinar cell apoptosis in SAP rats. GMTI therapy via i.v. + i.p. outperformed i.v. in improving pancreatic histology and reducing TNF-α and IL-6 serum levels in SAP rats. CONCLUSIONS: Our optimized SAP rat model is reliable and reproducible. GMTI therapy is a promising approach against SAP.


Asunto(s)
Gabexato , Pancreatitis , Ratas , Animales , Pancreatitis/inducido químicamente , Pancreatitis/tratamiento farmacológico , Pancreatitis/patología , Gabexato/efectos adversos , Poloxámero/farmacología , Interleucina-6 , Factor de Necrosis Tumoral alfa , Ratas Sprague-Dawley , Ácido Taurocólico , Enfermedad Aguda , Páncreas/patología
4.
Cancer Cell Int ; 22(1): 21, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-35033072

RESUMEN

BACKGROUND: Molecular markers play an important role in predicting clinical outcomes in pancreatic adenocarcinoma (PAAD) patients. Analysis of the ferroptosis-related genes may provide novel potential targets for the prognosis and treatment of PAAD. METHODS: RNA-sequence and clinical data of PAAD was downloaded from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) public databases. The PAAD samples were clustered by a non-negative matrix factorization (NMF) algorithm. The differentially expressed genes (DEGs) between different subtypes were used by "limma_3.42.2" package. The R software package clusterProfiler was used for functional enrichment analysis. Then, a multivariate Cox proportional and LASSO regression were used to develop a ferroptosis-related gene signature for pancreatic adenocarcinoma. A nomogram and corrected curves were constructed. Finally, the expression and function of these signature genes were explored by qRT-PCR, immunohistochemistry (IHC) and proliferation, migration and invasion assays. RESULTS: The 173 samples were divided into 3 categories (C1, C2, and C3) and a 3-gene signature model (ALOX5, ALOX12, and CISD1) was constructed. The prognostic model showed good independent prognostic ability in PAAD. In the GSE62452 external validation set, the molecular model also showed good risk prediction. KM-curve analysis showed that there were significant differences between the high and low-risk groups, samples with a high-risk score had a worse prognosis. The predictive efficiency of the 3-gene signature-based nomogram was significantly better than that of traditional clinical features. For comparison with other models, that our model, with a reasonable number of genes, yields a more effective result. The results obtained with qPCR and IHC assays showed that ALOX5 was highly expressed, whether ALOX12 and CISD1 were expressed at low levels in tissue samples. Finally, function assays results suggested that ALOX5 may be an oncogene and ALOX12 and CISD1 may be tumor suppressor genes. CONCLUSIONS: We present a novel prognostic molecular model for PAAD based on ferroptosis-related genes, which serves as a potentially effective tool for prognostic differentiation in pancreatic cancer patients.

5.
J Neurochem ; 156(1): 59-75, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32383496

RESUMEN

Natural scenes contain complex visual cues with specific features, including color, motion, flicker, and position. It is critical to understand how different visual features are processed at the early stages of visual perception to elicit appropriate cellular responses, and even behavioral output. Here, we studied the visual orientation response induced by flickering stripes in a novel behavioral paradigm in Drosophila melanogaster. We found that free walking flies exhibited bandpass orientation response to flickering stripes of different frequencies. The most sensitive frequency spectrum was confined to low frequencies of 2-4 Hz. Through genetic silencing, we showed that lamina L1 and L2 neurons, which receive visual inputs from R1 to R6 neurons, were the main components in mediating flicker-induced orientation behavior. Moreover, specific blocking of different types of lamina feedback neurons Lawf1, Lawf2, C2, C3, and T1 modulated orientation responses to flickering stripes of particular frequencies, suggesting that bandpass orientation response was generated through cooperative modulation of lamina feedback neurons. Furthermore, we found that lamina feedback neurons Lawf1 were glutamatergic. Thermal activation of Lawf1 neurons could suppress neural activities in L1 and L2 neurons, which could be blocked by the glutamate-gated chloride channel inhibitor picrotoxin (PTX). In summary, lamina monopolar neurons L1 and L2 are the primary components in mediating flicker-induced orientation response. Meanwhile, lamina feedback neurons cooperatively modulate the orientation response in a frequency-dependent way, which might be achieved through modulating neural activities of L1 and L2 neurons.


Asunto(s)
Encéfalo/fisiología , Neuronas/fisiología , Orientación Espacial/fisiología , Percepción Visual/fisiología , Animales , Drosophila melanogaster , Retroalimentación , Estimulación Luminosa
6.
Ann Diagn Pathol ; 55: 151835, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34624626

RESUMEN

Juvenile hyaline fibromatosis (JHF) is an extremely rare autosomal recessive disease that typically presents in infancy or early childhood. Largely due to the rarity, JHF is still not widely recognized by clinicians and pathologists in China. It is not uncommonly to misdiagnose the disease as other types of disorders. In this study, we present our experience with five cases of JHF to enhance the recognition of this rare but distinctive entity. There were 4 males and 1 female, with age at presentation ranging from 5 to 44 years. All patients presented with multiple subcutaneous nodular lesions of varying size in various parts of the body since birth or early childhood. Three patients also had joint involvement. Pathologically, the lesions were poorly circumscribed, located mainly in the dermis and subcutis. All five cases were characterized by abundant homogeneous hyaline-like matrix that differs sharply from the adjacent connective tissue, which stained strongly with periodic acid-Schiff (PAS) and was diastase resistant. Embedded within the eosinophilic glassy matrix were cords or small clusters of plump spindled to epithelioid cells, frequently with clear cytoplasm. Familiarity with the characteristic features of JHF is not only important in avoiding misdiagnosis but also essential for clinical management and prognostic evaluation.


Asunto(s)
Síndrome de Fibromatosis Hialina , Adolescente , Adulto , Preescolar , China , Trastornos de los Cromosomas/diagnóstico , Trastornos de los Cromosomas/patología , Femenino , Humanos , Síndrome de Fibromatosis Hialina/diagnóstico , Síndrome de Fibromatosis Hialina/patología , Masculino , Pronóstico , Receptores de Péptidos/análisis , Receptores de Péptidos/metabolismo , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/patología
7.
Med Sci Monit ; 24: 5185-5191, 2018 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-30047547

RESUMEN

BACKGROUND Prostate cancer (PCa) is a prevalent cancer in males. CXCR7 exhibits oncogenic actions in various cancers. The aim of our study was to explore the clinical significance of CXCR7 in patients with PCa. MATERIAL AND METHODS QRT-PCR was used to detect the expression level of CXCR7 in PCa tissues. The relationship between CXCR7 expression and clinicopathologic parameters was evaluated by chi-square test. Kaplan-Meier survival curve was used for the survival analysis of patients. Cox regression analyses were performed to assess the potential of CXCR7 as a prognosis biomarker for PCa patients. We performed MTT and Transwell assays to determine the effect of CXCR7 on proliferative and migratory abilities of PCa cells, respectively. RESULTS CXCR7 was upregulated in PCa tissues (P<0.05) and was correlated with PSA (P=0.023), differentiation (P=0.022), and lymph node metastasis (P=0.018). The results of MTT and Transwell assays demonstrated that inhibition of CXCR7 suppressed PCa cells growth and migration. Additionally, high CXCR7 level predicted poor overall survival (log rank test, P=0.019). CXCR7 was a valuable prognostic biomarker for PCa patients (HR=2.271, 95%CI=1.093-4.719, P=0.028). CONCLUSIONS CXCR7 is an oncogene in PCa that can promote aggressive progression of PCa through enhancing proliferation and migration of the tumor cells. CXCR7 is an independent biomarker for the prognosis of PCa.


Asunto(s)
Neoplasias de la Próstata/metabolismo , Receptores CXCR/metabolismo , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Diferenciación Celular/fisiología , Línea Celular Tumoral , Proliferación Celular/fisiología , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Pronóstico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Receptores CXCR/genética , Transducción de Señal , Análisis de Supervivencia , Regulación hacia Arriba
8.
Acta Biochim Biophys Sin (Shanghai) ; 50(3): 298-306, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29425256

RESUMEN

Type 2 diabetes mellitus (T2DM) leads to cognitive impairment (CI), but there have been no effective pharmacotherapies or drugs for cognitive dysfunction in T2DM. Dihydromyricetin (DHM) is a natural flavonoid compound extracted from the leaves of Ampelopsis grossedentata and has various pharmacological effects including anti-oxidant and anti-diabetes. Thus, we investigated the effects of DHM on CI in T2DM mouse model and its possible mechanism. To induce T2DM, mice were fed with high-sugar and high-fat diet for 8 weeks, followed by a low dose streptozotocin (STZ) administration. After the successful induction of T2DM mouse model, mice were treated respectively with equal volume of saline (T2DM group), 125 mg/kg/d DHM (L-DHM group), or 250 mg/kg/d DHM (H-DHM group). After 16 weeks of DHM administration, the body weight (BW), fasting blood glucose, blood lipids, intraperitoneal glucose tolerance (IPGT), and cognitive function were determined. Then, alterations in the expressions of oxidative stress markers and brain-derived neurotrophic factor (BDNF) in the hippocampus were investigated. Our findings demonstrated that DHM could significantly ameliorate CI and reverse aberrant glucose and lipid metabolism in T2DM mice, likely through the suppression of oxidative stress and enhancement of BDNF-mediated neuroprotection. In conclusion, our results suggest that DHM is a promising candidate for the treatment of T2DM-induced cognitive dysfunction.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/metabolismo , Disfunción Cognitiva/prevención & control , Diabetes Mellitus Tipo 2/complicaciones , Flavonoles/farmacología , Neuroprotección/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Ampelopsis/química , Animales , Glucemia/metabolismo , Factor Neurotrófico Derivado del Encéfalo/genética , Disfunción Cognitiva/etiología , Disfunción Cognitiva/metabolismo , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Tipo 2/sangre , Aprendizaje por Laberinto/efectos de los fármacos , Ratones , Fármacos Neuroprotectores/farmacología , Fitoterapia , Extractos Vegetales/farmacología
9.
Biochem Cell Biol ; 95(3): 361-367, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28177764

RESUMEN

Long non-coding RNAs (lncRNAs) are transcripts longer than 200 nucleotides without protein-coding potential. Although these molecules were initially considered as "junk products" of transcription without biological relevance, recent advances in research have shown that lncRNA plays an important role, not only in cellular processes such as proliferation, differentiation, and metabolism, but also in the pathological processes of cancers, diabetes, and neurodegenerative diseases. In this review, we focus on the potential regulatory roles of lncRNA in diabetes and the complications associated with diabetes.


Asunto(s)
Complicaciones de la Diabetes/fisiopatología , Diabetes Mellitus/fisiopatología , ARN Largo no Codificante/genética , Animales , Humanos
10.
Nano Lett ; 16(2): 1472-7, 2016 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-26808215

RESUMEN

Optical metafluids that consist of colloidal solutions of plasmonic and/or excitonic nanomaterials may play important roles as functional working fluids or as means for producing solid metamaterial coatings. The concept of a metafluid employed here is based on the picture that a single ballistic photon, propagating through the metafluid, interacts with a large collection of specifically designed optically active nanocrystals. We demonstrate water-based metafluids that act as broadband electromagnetic absorbers in a spectral range of 200-3300 nm and feature a tunable narrow (∼100 nm) transparency window in the visible-to-near-infrared region. To define this transparency window, we employ plasmonic gold nanorods. We utilize excitonic boron-doped silicon nanocrystals as opaque optical absorbers ("optical wall") in the UV and blue-green range of the spectrum. Water itself acts as an opaque "wall" in the near-infrared to infrared. We explore the limits of the concept of a "simple" metafluid by computationally testing and validating the effective medium approach based on the Beer-Lambert law. According to our simulations and experiments, particle aggregation and the associated decay of the window effect are one example of the failure of the simple metafluid concept due to strong interparticle interactions.

11.
Tumour Biol ; 35(6): 5763-9, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24590268

RESUMEN

The rs2736100 polymorphism in the telomerase reverse transcriptase (TERT) gene has been implicated in lung cancer risk in multiple populations, but the existing evidence lacks statistical power to draw a convincing conclusion. Therefore, the present study was devised to derive a more precise estimation of the association between rs2736100 and lung cancer risk. The PubMed, Embase, and Web of Science databases were comprehensively searched for papers concerning lung cancer risk in relation to rs2736100. Pooled odds ratios (ORs) and the 95 % confidence intervals (CIs) were appropriately calculated using the fixed or random effects model. Meta-analysis of 20 independent studies involving 39,715 cancer cases and 61,462 control subjects showed statistical evidence for an association between rs2736100 and increased risk of lung cancer. Subgroup analysis by ethnicity demonstrated a significant association among both Asian and Caucasian populations. We additionally found an increased risk of non-small cell lung cancer and lung adenocarcinoma strongly associated with rs2736100. These data provide further evidence supporting a role for genetic susceptibility of TERT rs2736100 in the development of lung cancer.


Asunto(s)
Predisposición Genética a la Enfermedad , Neoplasias Pulmonares/genética , Polimorfismo Genético , Telomerasa/genética , Humanos , Neoplasias Pulmonares/etiología , Sesgo de Publicación , Riesgo
12.
Metab Brain Dis ; 29(1): 87-92, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23975537

RESUMEN

Colorectal cancer (CRC) is one of the most common tumors. CRC patients are susceptible to suffering from depression. Whether the immune system of CRC patients with depression is impaired or stimulated is controversial. Possible reasons for this conflict are the involvement of confounding factors, such as the age of the patient, the stage of the CRC and the types of treatment in previous studies. To demonstrate clearly the relationship between depression and the immune system in the context of CRC, the present study included only older patients with advanced CRC who received only chemotherapy, and the study adopted immunosuppressive acidic protein (IAP) as an immune parameter for the first time. A total of 56 older patients with advanced CRC completed the Zung Self-Rating Depression Scale (SDS) and were divided into two groups according to SDS scores. The patients exhibiting depression were treated with fluoxetine until their symptoms remitted. The serum levels of IAP and the percentages of CD3-positive (CD3+), CD4+, CD8+ T lymphocytes and CD56+ natural killer (NK) cells and Neutrophil-lymphocyte ratio (NLR) were calculated at the time of enrollment and once the symptoms remitted. Correlation analyses revealed that the SDS score was positively associated with serum IAP levels but negatively associated with CD3 and CD4 levels. Among the depressed and non-depressed patients, serum IAP levels and the percentages of CD3 and CD4 cells were dramatically different. After the depression symptoms were treated, the IAP levels dramatically decreased, while the levels of CD3, CD4, CD8 and CD56 were unchanged. All of above suggested that IAP was closely correlated with depression and might be a relatively objective parameter for predicting depression.


Asunto(s)
Adenocarcinoma/psicología , Neoplasias Colorrectales/psicología , Depresión/sangre , Proteínas de Neoplasias/sangre , Adenocarcinoma/sangre , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/inmunología , Anciano , Anciano de 80 o más Años , Antidepresivos de Segunda Generación/uso terapéutico , Antígenos CD/análisis , Antineoplásicos/uso terapéutico , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/inmunología , Depresión/tratamiento farmacológico , Depresión/inmunología , Femenino , Fluoxetina/uso terapéutico , Humanos , Células Asesinas Naturales/inmunología , Recuento de Leucocitos , Masculino , Neutrófilos , Autoinforme , Índice de Severidad de la Enfermedad , Linfocitos T/inmunología
13.
Tuberculosis (Edinb) ; 148: 102530, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38857553

RESUMEN

OBJECTIVES: To determine the usefulness of LINC00152 and LARS2-AS1 as potential biomarkers for latent tuberculosis (LTB) and active tuberculosis (ATB), as well as their effect on Mycobacterium (Mtb) infection. METHODS: The expression levels of LINC00152 and LARS2-AS1 in the health, patients with LTB and ATB were detected by qRT-PCR. The ROC curves were constructed to show their potential as biomarkers. The intracellular survival assays for Mtb and the levels of immune-related cytokines were determined to discover the effect of LINC00152 and LARS2-AS1 on Mtb infection. The relationships of miR-485-5p with LINC00152 and LARS2-AS1 were explored. RESULTS: LINC00152 and LARS2-AS1 levels were significantly elevated in patients with ATB and LTB, and Mtb-infected macrophages. LINC00152 and LARS2-AS1 can distinguish the LTB from the health and ATB from LTB. LARS2-AS1 and LINC00152 knock-down reduced the intracellular Mtb survival and induced cellular immune response after Mtb challenge. miR-485-5p was a targeting miRNA for LINC00152 and LARS2-AS1. CONCLUSIONS: LINC00152 and LARS2-AS1 can be considered as potential biomarkers for tuberculosis disease. LINC00152 and LARS2-AS1 have anti-Mtb effects.

14.
Int J Biol Macromol ; 267(Pt 1): 131406, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38582472

RESUMEN

Starch and plant fibers are abundant natural polymers that offer biodegradability, making them potential substitutes for plastics in certain applications, but are usually limited by its high hydrophilicity, and low mechanical performance. To address this issue, polylactic acid (PLA) is blended with cellulose and chitosan to create a waterproof film that can be applied to starch-fiber foaming biodegradable composites to enhance their water resistance properties. Here, plant fibers as a reinforcement is incorporated to the modified starch by foaming mold at 260 °C, and PLA based hydrophobic film is coated onto the surface to prepare the novel hydrophobic bio-composites. The developed bio-composite exhibits comprehensive water barrier properties, which is significantly better than that of traditional starch and cellulose based materials. Introducing PLA films decreases water vapor permeability from 766.83 g/m2·24h to 664.89 g/m2·24h, and reduce hysteresis angles from 15.57° to 8.59° within the first five minutes after exposure to moisture. The water absorption rate of PLA films also decreases significantly from 12.3 % to 7.9 %. Additionally, incorporating hydrophobic films not only enhances overall waterproof performance but also improves mechanical properties of the bio-composites. The fabricated bio-composite demonstrates improved tensile strength from 2.09 MPa to 3.53 MPa.


Asunto(s)
Interacciones Hidrofóbicas e Hidrofílicas , Poliésteres , Almidón , Resistencia a la Tracción , Agua , Poliésteres/química , Almidón/química , Agua/química , Permeabilidad , Quitosano/química , Celulosa/química , Vapor , Propiedades de Superficie
15.
Artículo en Inglés | MEDLINE | ID: mdl-38619108

RESUMEN

The accumulation of ice can pose numerous inconveniences and potential hazards, profoundly affecting both human productivity and daily life. To combat the challenges posed by icing, extensive research efforts have been dedicated to the development of low-ice adhesion surfaces. In this study, we harness the power of molecular dynamics simulations to delve into the intricate dynamics of polymer chains and their role in determining the modulus of the material. We present a novel strategy to prepare ultralow-modulus poly(dimethylsiloxane) (PDMS) elastomers with a molecular brush configuration as icephobic materials. The process involves grafting monohydride-terminated PDMS (H-PDMS) as side chains onto backbone chain PDMS with pendant vinyl functional groups to yield a molecular brush structure. The segments of this polymer structure effectively restrict interchain entanglement, thereby rendering a lower modulus compared to traditional linear structures at an equivalent cross-linking density. The developed soft coating exhibits a remarkably ultralow ice adhesion strength of 13.1 ± 1.1 kPa. Even after enduring 50 cycles of icing and deicing, the ice adhesion strength of this coating steadfastly stayed below 16 kPa, showing no notable increase. Importantly, the molecular brush coating applied to glass demonstrated an impressive light transmittance of 92.1% within the visible light spectrum, surpassing the transmittance of bare glass, which was measured at 91.3%. This icephobic coating with exceptional light transmittance offers a wide range of applications and holds significant potential as a practical icephobic material.

16.
Nano Lett ; 12(8): 4200-5, 2012 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-22757779

RESUMEN

A lack of consensus persists regarding the origin of photoluminescence in silicon nanocrystals. Here we report pressure-dependences of X-ray diffraction and photoluminescence from alkane-terminated colloidal particles. We determine the diamond-phase bulk modulus, observe multiple phase transitions, and importantly find a systematic photoluminescence red shift that matches the X(conduction)-to-Γ(valence) transition of bulk crystalline silicon. These results, reinforced by calculations, suggest that the efficient photoluminescence, frequently attributed to defects, arises instead from core-states that remain highly indirect despite quantum confinement.

17.
Carbohydr Polym ; 307: 120627, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-36781278

RESUMEN

Starch is regarded as one of the most promising sustainable materials due to its abundant yield and excellent biodegradability. From the perspective of practical engineering applications, this paper systematically describes the development of starch-based bio-composites in the past decade. Packaging properties, processing characteristics, and current challenges for the efficient processing of starch-based bio-composites are reviewed in industrial packaging. Green coatings, binders, adsorbents, flocculants, flame retardants, and emulsifiers are used as examples to illustrate the versatility of starch-based bio-composites in chemical agent applications. In addition, the work compares the application of starch-based bio-composites in conventional spinning with emerging spinning technologies and describes the challenges of electrostatic spinning for preparing nanoscale starch-based fibers. In terms of flexible electronics, the starch-based bio-composites are regard as a solid polymer electrolyte and easily modified porous material. Moreover, we describe the applications of the starch-based gels in tissue engineering, controlled drug release, and medical dressings. Finally, the theoretical input and technical guidance in the advanced sustainable engineering application of the starch-based bio-composites are provided in the work.


Asunto(s)
Polímeros , Almidón , Almidón/química , Ingeniería de Tejidos
18.
Cancers (Basel) ; 15(13)2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37444481

RESUMEN

Immunotherapy has transformed lung cancer management, but PSC remains an aggressive subtype with a poor prognosis. This study investigates the differential expression of PD-L1 and alternative immune checkpoints (ICs; B7x, B7-H3, and HHLA2), and genetic alterations in PSCs. Tumor specimens of 41 PSC patients were evaluated. PD-L1, B7x, B7-H3, and HHLA2 were positive in 75.0%, 67.6%, 73.0%, and 91.9% of tumors, respectively. PD-L1 expression was significantly higher in the epithelial compared to the sarcomatoid component (median TPS: 50% vs. 0%, p = 0.010). Expression of PD-L1 in both components was only seen in 32.1% of patients. However, at least one IC was expressed in 92.9% of epithelial and 100% of sarcomatoid components. Furthermore, METex14 was detected in 19.5% of patients and was associated with a higher sarcomatoid percentage. Our preclinical studies revealed that METex14 induced PD-L1 expression via MAPK or PI3K/Akt pathways, and MET inhibitors decreased PD-L1 expression. Our findings demonstrate distinct expressions of ICs in PSC subcomponents. Thus, combination IC inhibition as a therapeutic strategy in PSC warrants further exploration. A high percentage of METex14 in PSC and its role in regulating PD-L1 expression reveal different therapeutic targets in this aggressive NSCLC subtype.

19.
Transl Lung Cancer Res ; 12(4): 808-823, 2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37197623

RESUMEN

Background: Tumor mutation burden (TMB) is one of the biomarkers for efficacy of immune checkpoint inhibitors (ICIs) in non-small cell lung cancer (NSCLC). Due to the potential of radiomic signatures to identify microscopic genetic and molecular differences, thus radiomics is considered a suitable tool for judging the TMB status probably. In this paper, the radiomics method was applied to analyze the TMB status of NSCLC patients, so as to construct a prediction model for distinguishing between TMB-high and TMB-low status. Methods: A total of 189 NSCLC patients with TMB detection result were retrospectively included between 30 November 2016 and 1 January 2021, and were divided into two groups: TMB-high (≥10/Mb, 46 patients) and TMB-low (<10/Mb, 143 patients). Some clinical features related to TMB status were screened out in 14 clinical features and 2,446 radiomic features were extracted. All patients were randomly divided into a training set (n=132) and a validation set (n=57). Univariate analysis and least absolute shrinkage and selection operator (LASSO) were used for radiomics feature screening. A clinical model, radiomics model, and nomogram were constructed with the above screened features and compared. Decision curve analysis (DCA) was used to evaluate the clinical value of the established models. Results: Two clinical features (smoking history, pathological type) and 10 radiomics features were significantly correlated with the TMB status. The prediction efficiency of the intra-tumoral model was better than that of the peritumoral model (AUC: 0.819 vs. 0.816; accuracy: 0.773 vs. 0.632, specificity: 0.767 vs. 0.558). The efficacy of the prediction model based on radiomic features was significantly better than that of the clinical model (AUC: 0.822 vs. 0.683; specificity: 0.786 vs. 0.643). The nomogram, established by combining smoking history, pathologic type, and rad-score, showed the best diagnostic efficacy (AUC =0.844) and had potential clinical value in assessing the TMB status of NSCLC. Conclusions: The radiomics model based on CT images of NSCLC patients performed well in distinguishing the status of TMB-high and TMB-low, and the nomogram could provide additional information on the timing and regimen of immunotherapy.

20.
Radiol Case Rep ; 18(5): 1796-1808, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36915609

RESUMEN

A subcutaneous abscess of the penis is a rare condition. It can be idiopathic or have an underlying cause, such as intracavernous injection therapy, foreign body, dilated perineal abscess, abnormal erection, or trauma. Clinical signs are mainly swelling in the penis, penile pain, and swelling. Conventional treatment is primarily surgical incision and drainage, followed by systemic antibiotic therapy. In recent years, with the development of medical technology, minimally invasive interventions and less invasive techniques, such as ultrasound-guided aspiration, are being developed. This article aims to report a case of ultrasound-guided successful diagnosis and treatment of an aseptic idiopathic subcutaneous abscess at the root of the penis and to review the literature on penile abscesses. The patient, a 61-year-old male, underwent ultrasound-guided puncture and drainage using a coaxial aspiration/flushing technique in combination with antibiotics to treat this rare urinary tract condition. The patient recovered well postoperatively and was discharged 3 days later. At a 2-week postoperative follow-up, an ultrasound showed a marked reduction in the penile abscess mass.

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