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1.
BMC Gastroenterol ; 24(1): 218, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977950

RESUMO

BACKGROUND: Studies attempted to estimate MASLD-related advanced fibrosis (AF) and cirrhosis (MC) prevalence utilized tests with low positive predictive value (PPV) which overestimates prevalence. AGILE3 + and 4 scores were developed to increase the PPV of both; respectively. In this study, we used these scores to assess the prevalence of AF and MC. METHODS: Participants aged ≥ 18 years with VCTE exam in the NHANES 2017-2018 cycle were included. We excluded pregnant women, patients with excessive alcohol intake, hepatitis B/C, and ALT or AST > 500 IU/L. MASLD was defined with CAP score > 248 dB/m. MASLD subjects with AGILE 3 + score of ≥ 0.68 and AGILE 4 score of ≥ 0.57 were considered to have advanced fibrosis and cirrhosis; respectively. AGILE 3 + of 0.45-0.67 and AGILE 4 of 0.25-0.57 were grey zone, whereas AGILE 3 + < 0.45 and AGILE 4 < 0.25 were considered a rule-out. RESULTS: 1244 subjects were included in the final analysis. The Median age was 53 (51.4-54.6) years, 55.6% were male, median BMI was 33.8 kg/m2 and 41.1% had T2DM. Based on AGILE 3+, 80.3% of the MASLD population were at low risk for AF and 11.5% were in grey zone. The prevalence of AF due to MASLD was 8.1% corresponding to 4.5 million Americans. Based on AGILE 4 score, 96.5% of the MASLD population were at low risk for cirrhosis and 2.4% were in the grey zone. The prevalence of MASLD-cirrhosis was 1.1% corresponding to 610,000 Americans. CONCLUSION: Our results suggest that approximately 4.5 million people in the U.S. have AF and 0.6 million have cirrhosis due to MASLD.


Assuntos
Cirrose Hepática , Inquéritos Nutricionais , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Prevalência , Cirrose Hepática/epidemiologia , Estados Unidos/epidemiologia , Fígado Gorduroso/epidemiologia , Fígado Gorduroso/complicações , Valor Preditivo dos Testes , Índice de Gravidade de Doença , Adulto
2.
Network ; : 1-24, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38994690

RESUMO

Plant diseases pose a significant threat to agricultural productivity worldwide. Convolutional neural networks (CNNs) have achieved state-of-the-art performances on several plant disease detection tasks. However, the manual development of CNN models using an exhaustive approach is a resource-intensive task. Neural Architecture Search (NAS) has emerged as an innovative paradigm that seeks to automate model generation procedures without human intervention. However, the application of NAS in plant disease detection has received limited attention. In this work, we propose a two-stage meta-learning-based neural architecture search system (ML NAS) to automate the generation of CNN models for unseen plant disease detection tasks. The first stage recommends the most suitable benchmark models for unseen plant disease detection tasks based on the prior evaluations of benchmark models on existing plant disease datasets. In the second stage, the proposed NAS operators are employed to optimize the recommended model for the target task. The experimental results showed that the MLNAS system's model outperformed state-of-the-art models on the fruit disease dataset, achieving an accuracy of 99.61%. Furthermore, the MLNAS-generated model outperformed the Progressive NAS model on the 8-class plant disease dataset, achieving an accuracy of 99.8%. Hence, the proposed MLNAS system facilitates faster model development with reduced computational costs.

3.
Int J Biometeorol ; 68(4): 795-806, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38374293

RESUMO

The exposure to high altitude and cold stress poses challenges in maintaining normal physiological standards and body homeostasis in non-native animals. To enhance our understanding of the physiology of native and non-native goats in high-altitude environments, we conducted a comparative study to examine the impact of natural hypoxic and cold stress conditions on their feed intake (FIT) and associated changes in physiological responses, including plasma glucose concentration (PGC). The study took place at an altitude of 3505.2 m above mean sea level and involved twenty-two healthy females from two different breeds of goats. This study was conducted over a period of 56 days after the arrival of non-native Black Bengal goats (BBN) and compared with native Changthangi (CHAN) goats. Both groups were extensively reared in a natural high-altitude and cold-stress environment in Leh, India, and were subjected to defined housing and management practices. The parameters evaluated included FIT, PGC, respiration rate, heart rate, pulse rate, and rectal temperature. High altitudes had a significant (p < 0.05) impact on FIT, PGC, respiration rate, heart rate, pulse rate, and rectal temperature in BBN, whereas these parameters remained stable in CHAN throughout the study period. Additionally, the detrimental effects of high-altitude stress were more pronounced in non-native goats compared to native goats. These findings suggest that physiological responses in non-native goats tend to stabilize after an initial period of adverse effects in high-altitude environments. Based on the physiological responses and glucose concentration, it is recommended to pay special attention to the nutrition of non-native goats for up to the third week (21 days) after their arrival in high-altitude areas.


Assuntos
Altitude , Glicemia , Animais , Feminino , Cabras/fisiologia , Meio Ambiente , Ingestão de Alimentos
4.
J Fluoresc ; 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37682499

RESUMO

Copper and Mercury ions have vital role to play in biological world as their excess or deficiency can cause different type of diseases in human being as well as biological species including plants and animals. Therefore, their detection at trace level becomes very important in term of biological. The current studies embody the fabrication, structural characterization and recognition behavior of a novel rhodamine B hydrazone formed when hydrazide of rhodamine B was condensed with 5-Allyl-3-methoxy salicylaldehyde (RBMA). RBMA was found to be responsive towards the very trace level of Cu2+ and Hg2+ among other tested cations so far. The sensing procedure is based on the classical opening of the spiroatom ring of rhodamine. The limit of detection (LOD) and binding constant is 5.35 ppm, 2.06 × 104 M-1 and 5.16 ppm, 1.26 × 104 M-1 for Cu2+ and Hg2+ ions respectively. The probable mechanism correlates the specific binding of RBMA with Cu2+ and Hg2+ ions. The 1:1 stoichiometry of RBMA with Cu2+ and Hg2+ ions have been supported by HRMS, FT-IR data, Job's plot, and binding constant data. Reversibility is well exhibited by RBMA by the involvement of CO32- ions via demetallation process. The real time application is well demonstrated by the use of paper strip test. The DFT study also carried out which agrees well with the experimental findings. The results displayed the novelty of this current work towards the trace level analysis of the Cu2+ and Hg2+ of the cations which are play the crucial role in industry.

5.
J Gastroenterol Hepatol ; 38(6): 984-988, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36869600

RESUMO

BACKGROUND AND AIM: A recent study has demonstrated that women with gestational diabetes mellitus (GDM) are more likely to develop non-alcoholic fatty liver disease than those without GDM. In contrary to non-alcoholic fatty liver, the association of GDM with non-alcoholic steatohepatitis (NASH) has still not been well established in the current literature. Therefore, we aim to evaluate the association of a history of GDM and the development of NASH throughout their lives independently of type 2 diabetes mellitus (T2DM). METHODS: A validated research database of more than 360 hospitals was utilized to construct this study. Adult females included were divided into two groups: those with NASH (case) and individuals without NASH (control). Regression analysis was performed to account for potential cofounders. RESULTS: There were 70 632 640 individuals above the age of 18 years screened in the database. In patients with a history of GDM, NASH was most prevalent in middle age people compared with NASH alone, which was more prevalent in people aged 65 years and above. Compared with those without, patients with NASH tend to be Caucasian (odds ratio [OR]: 2.13), obese (OR: 4.83), have a history of GDM (OR: 1.23), diagnosed with hyperlipidemia (OR: 2.59), T2DM (OR: 4.52), metabolic syndrome (OR: 3.07), polycystic ovaries disease (OR: 1.72), and hypothyroidism (OR: 1.59). CONCLUSION: We demonstrated for the first time an increased odd of developing NASH in women who have had a diagnosis of gestational diabetes mellitus throughout their lives independently of any other factors that could interfere with the results.


Assuntos
Diabetes Mellitus Tipo 2 , Diabetes Gestacional , Síndrome Metabólica , Hepatopatia Gordurosa não Alcoólica , Adulto , Pessoa de Meia-Idade , Gravidez , Humanos , Feminino , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Gestacional/epidemiologia , Síndrome Metabólica/complicações , Obesidade/complicações
6.
J Gastroenterol Hepatol ; 38(2): 269-273, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36328950

RESUMO

BACKGROUNDS: Nonalcoholic fatty liver disease (NAFLD) is linked to obesity and metabolic syndrome conditions. However, a subset of NAFLD patients express a normal or low body mass index (lean NAFLD [L-NAFLD]). Our aim is to compare the prevalence of L-NAFLD to the obesity-associated NAFLD in the United States by assessing prevalence, potential risk factors, liver-related complications, and coronary artery disease outcomes. METHODOLOGY: A multicenter database (Explorys Inc.) of >70 million patients across the United States was screened. A cohort of patients with "nonalcoholic fatty liver" between 1999 and 2021 was identified. Two sub-cohorts of NAFLD patients were identified: those with a body mass index (BMI) < 25 kg/m2 (L-NAFLD) and those with a BMI > 30 kg/m2 (obesity-associated NAFLD). We excluded patients with age <18 and those who have viral hepatitis, hemochromatosis, Wilson's disease, biliary cirrhosis, alcoholic liver disease, cystic fibrosis, alpha-1-antitrypsin deficiency, and autoimmune hepatitis. Multivariate analysis was performed to adjust for confounders. RESULTS: 68 892 260 individuals were screened. NAFLD prevalence was four per 100 000, and L-NAFLD prevalence was 0.6 per 100 000. Compared with those without, patients with L-NAFLD tended to be older (OR 2.16), females (OR 1.28), and smokers (OR 4.67) and of Asian race (OR 2.12). L-NAFLD patients were more likely to have acute coronary syndromes (OR 30.00) and metabolic syndrome (OR 2.31) despite the normal/low BMI. Esophageal varices and hepatocellular carcinoma risks were high in both cirrhosis patients. CONCLUSION: This is the largest study to assess L-NAFLD prevalence in the United States. L-NAFLD are at a significantly higher risk for acute coronary syndromes, esophageal varices, and hepatocellular carcinoma.


Assuntos
Síndrome Coronariana Aguda , Carcinoma Hepatocelular , Varizes Esofágicas e Gástricas , Neoplasias Hepáticas , Síndrome Metabólica , Hepatopatia Gordurosa não Alcoólica , Feminino , Humanos , Estados Unidos , Hepatopatia Gordurosa não Alcoólica/complicações , Carcinoma Hepatocelular/epidemiologia , Síndrome Metabólica/complicações , Prevalência , Varizes Esofágicas e Gástricas/complicações , Neoplasias Hepáticas/epidemiologia , Cirrose Hepática/etiologia , Fibrose , Obesidade/complicações , Estudos Multicêntricos como Assunto
7.
Dig Dis Sci ; 68(4): 1369-1380, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36002677

RESUMO

AIMS: Previous studies have reported conflicting results regarding prevalence of elevated LC (2-70%) in celiac disease (CD). This systematic review and meta-analysis assessed the prevalence of elevated LC at time of CD diagnosis and associated response to GFD. We also report the prevalence of CD in patients with unexplained elevation of LC. METHODS: Studies assessing LC (aspartate aminotransferase [AST] and alanine aminotransferase [ALT]) in CD patients were eligible. Studies with < 50 cases or in pediatric populations were excluded. RESULTS: In total, 20 studies assessing prevalence of elevated LC in 4,265 participants with newly diagnosed CD (mean age = 35.6 ± 6.5 years, 69.8% female) were included. Pooled prevalence of elevated LC was 18.7% (95% CI 13.8-24.8; I2 = 95%). Normalization of elevated LC was seen in 83.1% (95% CI 73.4-89.7; I2 = 79%, 11 studies) of patients after GFD. On meta-regression, age at CD diagnosis, gender, and Marsh grading were not associated with elevated LC. Among 979 participants (7 studies) with unexplained elevation of LC, pooled seroprevalence and biopsy-proven CD was 6.4% (95% CI 2.9-10.3, I2 = 71%) and 4.5% (95% CI 2.6-7.7, I2 = 67%), respectively. CONCLUSION: Elevated LC are seen in approximately one-fifth of patients at CD diagnosis with majority normalizing after GFD. Age, gender, and degree of intestinal damage are not predictive of elevated LC. In the appropriate clinical scenario, liver tests should be serially monitored in CD reserving workup for additional causes after a trial of GFD. Patients with unexplained elevation of liver tests should be screened for celiac disease.


Assuntos
Doença Celíaca , Criança , Humanos , Feminino , Adulto , Masculino , Doença Celíaca/diagnóstico , Doença Celíaca/epidemiologia , Doença Celíaca/complicações , Estudos Soroepidemiológicos , Fígado , Testes de Função Hepática , Alanina Transaminase , Dieta Livre de Glúten/métodos
8.
Entropy (Basel) ; 25(10)2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37895504

RESUMO

Of late, image compression has become crucial due to the rising need for faster encoding and decoding. To achieve this objective, the present study proposes the use of canonical Huffman coding (CHC) as an entropy coder, which entails a lower decoding time compared to binary Huffman codes. For image compression, discrete wavelet transform (DWT) and CHC with principal component analysis (PCA) were combined. The lossy method was introduced by using PCA, followed by DWT and CHC to enhance compression efficiency. By using DWT and CHC instead of PCA alone, the reconstructed images have a better peak signal-to-noise ratio (PSNR). In this study, we also developed a hybrid compression model combining the advantages of DWT, CHC and PCA. With the increasing use of image data, better image compression techniques are necessary for the efficient use of storage space. The proposed technique achieved up to 60% compression while maintaining high visual quality. This method also outperformed the currently available techniques in terms of both PSNR (in dB) and bit-per-pixel (bpp) scores. This approach was tested on various color images, including Peppers 512 × 512 × 3 and Couple 256 × 256 × 3, showing improvements by 17 dB and 22 dB, respectively, while reducing the bpp by 0.56 and 0.10, respectively. For grayscale images as well, i.e., Lena 512 × 512 and Boat 256 × 256, the proposed method showed improvements by 5 dB and 8 dB, respectively, with a decrease of 0.02 bpp in both cases.

9.
Gastrointest Endosc ; 95(6): 1239-1246, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35065946

RESUMO

BACKGROUND AND AIMS: Nanoscale nuclear architecture mapping (nanoNAM), an optical coherence tomography-derived approach, is capable of detecting with nanoscale sensitivity structural alterations in the chromatin of epithelial cell nuclei at risk for malignant transformation. Because these alterations predate the development of dysplasia, we aimed to use nanoNAM to identify patients with Barrett's esophagus (BE) who might progress to high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC). METHODS: This is a nested case-control study of 46 BE patients, of which 21 progressed to HGD/EAC over 3.7 ± 2.37 years (cases/progressors) and 25 patients who did not progress over 6.3 ± 3.1 years (control subjects/nonprogressors). The archived formalin-fixed paraffin-embedded tissue blocks collected as part of standard clinical care at the index endoscopy were used. nanoNAM imaging was performed on a 5-µm formalin-fixed paraffin-embedded section, and each nucleus was mapped to a 3-dimensional (3D) depth-resolved optical path difference (drOPD) nuclear representation, quantifying nanoscale-sensitive alterations in the 3D nuclear architecture of the cell. Using 3D-drOPD representation of each nucleus, we computed 12 patient-level nanoNAM features summarizing the alterations in intrinsic nuclear architecture. A risk prediction model was built incorporating nanoNAM features and clinical features. RESULTS: A statistically significant differential shift was observed in the drOPD cumulative distributions between progressors and nonprogressors. Of the 12 nanoNAM features, 6 (mean-maximum, mean-mean, mean-median, entropy-median, entropy-entropy, entropy-skewness) showed a statistically significant difference between cases and control subjects. NanoNAM features based prediction model identified progression in independent validation sets, with an area under the receiver operating characteristic curve of 80.8% ± .35% (mean ± standard error), with an increase to 82.54% ± .46% when combined with length of the BE segment. CONCLUSIONS: NanoNAM can serve as an adjunct to histopathologic evaluation of BE patients and aid in risk stratification.


Assuntos
Esôfago de Barrett , Neoplasias Esofágicas , Lesões Pré-Cancerosas , Adenocarcinoma , Esôfago de Barrett/patologia , Estudos de Casos e Controles , Progressão da Doença , Neoplasias Esofágicas/patologia , Formaldeído , Humanos , Hiperplasia , Projetos Piloto , Lesões Pré-Cancerosas/patologia , Medição de Risco
10.
BMC Gastroenterol ; 22(1): 366, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35907827

RESUMO

BACKGROUND: The prevalence of fatty liver disease is potentially increasing in adolescents and young adults (AYAs) due to the obesity and alcohol pandemics. The aim of this study was to assess the prevalence of alcohol-associated fatty liver disease (ALD) and nonalcoholic fatty liver disease (NAFLD) in a representative U.S. cohort utilizing transient elastography to directly measure hepatic steatosis and suspected fibrosis. METHODS: AYAs (age 15-39 years) with valid FibroScan® measurements in the National Health and Nutrition Examination Survey (NHANES) database (2017-2018) were included in the analyses. Those with viral hepatitis, pregnancy, or ALT/AST > 500 U/L were excluded. The population was divided into those with excessive alcohol consumption (ALQ130) and those without. Controlled attenuation parameter (CAP) score ≥ 248 dB/m was used to identify suspected ALD and NAFLD. In those with evidence of ALD, the following cutoffs of liver stiffness measurement (LSM) were used for suspected fibrosis: F ≥ F2 at LSM ≥ 7.5 kPa and F ≥ F3 at ≥ 9.5 kPa, respectively. In those with suspected NAFLD, the following LSM cutoffs were used: F ≥ F2 at 6.1 and F ≥ F3 at ≥ 7.1, respectively. Cutoffs were chosen based on published literature to maximize sensitivity. RESULTS: Comparing to those without, subjects with excessive alcohol consumption tended to be older (29.8 vs 28.5 years), have a higher BMI (29.3 vs 28.9 kg/m2), and be from a White ethnicity (65.3% vs. 55.4%). In subjects with excessive alcohol consumption, suspected ALD was present in 56.59% (95% CI 41.57-70.49). In those with suspected ALD, suspected significant fibrosis (F ≥ F2) was present in 12.3% (95% CI 4.74-28.34) and advanced fibrosis (F ≥ F3) was present in 6.31% (95% CI 0.69-39.55). Similarly, in subjects without excessive alcohol consumption, suspected NAFLD was present in 40.04% (36.64-43.54). In those with suspected NAFLD, suspected significant fibrosis (F ≥ F2) was present in 31.07% (27.25-35.16) and suspected advanced fibrosis (F ≥ F3) was present in 20.15% (16.05-24.99). CONCLUSION: A significant percentage of AYAs are at risk for ALD and NAFLD and a subset of these subjects is at risk for significant fibrosis. Efforts should focus on increasing awareness of the prevalence of ALD and NAFLD in this population and to mitigate modifiable risk factors.


Assuntos
Técnicas de Imagem por Elasticidade , Hepatopatia Gordurosa não Alcoólica , Adolescente , Adulto , Humanos , Fígado/patologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/epidemiologia , Cirrose Hepática/etiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Inquéritos Nutricionais , Prevalência , Estados Unidos/epidemiologia , Adulto Jovem
11.
J Biochem Mol Toxicol ; 36(7): e23064, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35385166

RESUMO

Ubiquitin proteasome system (UPS) and autophagy both pathways are involved in clearing the nonessential cellular components and also crosstalk during cellular response to normal and stress conditions. The F-box motif proteins constitute the SCF-E3 ligase complex of the UPS pathway in Saccharomyces cerevisiae and are involved in the substrate recruitment for ubiquitination. The ATG1 encoded Atg1p, a conserved serine-threonine kinase is crucial for the autophagy process. Here in this study, we report that loss of F-box motif encoding YDR131C and ATG1 together results in growth defects, floc formation, sensitivity to hydroxyurea, methyl methanesulfonate, and hydrogen peroxide. Both the genes also interact with the flocculation-related genes (FLO) and associate with gene ontology terms "ubiquitin-protein transferase activity" and "cellular catabolic process." Based on in silico analysis and experimental evidence we conclude that YDR131C and ATG1 function in parallel pathways to regulate the growth, flocculation, and stress response.


Assuntos
Proteínas F-Box , Proteínas de Saccharomyces cerevisiae , Autofagia/fisiologia , Proteínas Relacionadas à Autofagia/metabolismo , Motivos F-Box , Proteínas F-Box/metabolismo , Floculação , Proteínas Quinases/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Ubiquitina/metabolismo
12.
Scand J Gastroenterol ; 56(5): 624-628, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33764825

RESUMO

Endoscopic eradication therapy (EET) with maximal acid suppression is the cornerstone for the management of patients with Barrett's esophagus (BE) associated dysplasia. The occurrence of buried dysplastic glands after re-epithelialization of a neo-squamous epithelium is of concern for endoscopists. Here, we present a patient with BE and high-grade dysplasia successfully treated by EET who developed buried dysplastic BE during surveillance. A review of literature on buried dysplasia after successful endoscopic therapy of BE is also discussed.


Assuntos
Esôfago de Barrett , Neoplasias Esofágicas , Lesões Pré-Cancerosas , Esôfago de Barrett/cirurgia , Neoplasias Esofágicas/etiologia , Neoplasias Esofágicas/cirurgia , Esofagoscopia , Humanos , Hiperplasia
13.
J Biochem Mol Toxicol ; 35(7): e22781, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33797855

RESUMO

Nonavailability of glucose as a carbon source results in glyoxylate pathway activation, which metabolizes nonfermentable carbon for energy generation in Saccharomyces cerevisiae. Ucc1p of S. cerevisiae inhibits activation of the glyoxylate pathway by targeting Cit2p, a key glyoxylate enzyme for ubiquitin-mediated proteasomal degradation when glucose is available as a carbon source. Sro9p, a La-motif protein involved in RNA biogenesis, interacts physically with the messenger RNA of UCC1; however, its functional relevance is yet to be discovered. This study presents binary epistatic interaction between UCC1 and SRO9, with functional implication on the growth rate, response to genotoxic stress, resistance to apoptosis, and petite mutation. Cells with ucc1Δsro9Δ, as their genetic background, exhibit alteration in morphology, improvement in growth rate, resistance to apoptosis, and petite mutation. Moreover, the study indicates a cross-link between ubiquitin-proteasome system and RNA biogenesis and metabolism, with applications in industrial fermentation and screening for cancer therapeutics.


Assuntos
Glioxilatos/metabolismo , Proteínas dos Microfilamentos , RNA Fúngico , RNA Mensageiro , Proteínas de Ligação a RNA , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , RNA Fúngico/genética , RNA Fúngico/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
14.
Nano Lett ; 20(9): 6372-6380, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32786947

RESUMO

A damping-like spin-orbit torque (SOT) is a prerequisite for ultralow-power spin logic devices. Here, we report on the damping-like SOT in just one monolayer of the conducting transition-metal dichalcogenide (TMD) TaS2 interfaced with a NiFe (Py) ferromagnetic layer. The charge-spin conversion efficiency is found to be 0.25 ± 0.03 in TaS2(0.88)/Py(7), and the spin Hall conductivity (14.9×105ℏ2eΩ-1m-1) is found to be superior to values reported for other TMDs. We also observed sizable field-like torque in this heterostructure. The origin of this large damping-like SOT can be found in the interfacial properties of the TaS2/Py heterostructure, and the experimental findings are complemented by the results from density functional theory calculations. It is envisioned that the interplay between interfacial spin-orbit coupling and crystal symmetry yielding large damping-like SOT. The dominance of damping-like torque demonstrated in our study provides a promising path for designing the next-generation conducting TMD-based low-powered quantum memory devices.

15.
J Synchrotron Radiat ; 26(Pt 3): 793-800, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31074444

RESUMO

W/B4C multilayers (MLs) consisting of ten layer pairs with varying boron carbide layer thicknesses have been investigated. The ML structures were characterized using grazing-incidence hard X-ray reflectivity (GIXR), resonant soft X-ray reflectivity (RSXR), hard X-ray photoelectron spectroscopy (HAXPES) and X-ray absorption near-edge spectroscopy (XANES). Depth-resolved spectroscopic information on the boron carbide layer in W/B4C MLs was extracted with sub-nanometre resolution using reflectivity performed in the vicinity of the B K-edge. Interestingly, these results show that the composition of boron carbide films is strongly dependent on layer thicknesses. HAXPES measurements suggest that most of the boron is in the chemical state of B4C in the multilayer structures. XANES measurements suggest an increase in boron content and C-B-C bonding with increase in boron carbide layer thickness.

16.
Apoptosis ; 23(2): 113-131, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29349707

RESUMO

Piperazine scaffolds or 2-azetidinone pharmacophores have been reported to show anti-cancer activities and apoptosis induction in different types of cancer cells. However, the mechanistic studies involve in induction of apoptosis addressing these two moieties for human cervical cancer cells remain uncertain. The present study emphasizes on the anti-proliferating properties and mechanism involved in induction of apoptosis for these structurally related azoles derivatives in HeLa cancer cells. 1-Phenylpiperazine clubbed with 2-azetidione derivatives (5a-5h) were synthesized, characterized using various spectroscopic techniques and evaluated for their in-vitro anti-proliferative activities and induction of apoptosis. Further, we also evaluated oxidative stress generated by these synthetic derivatives (5a-5h). Cell viability studies revealed that among all, the compound N-(3-chloro-2-(3-nitrophenyl)-4-oxoazetidin-1-yl)-2-(4-phenylpiperazin-1-yl) acetamide 5e remarkably inhibited the growth of HeLa cells in a concentration dependent manner having IC50 value of 29.44 ± 1.46 µg/ml. Morphological changes, colonies suppression and inhibition of migration clearly showed the antineoplasicity in HeLa cells treated with 5e. Simultaneously, phosphatidylserine externalization, DNA fragmentation and cell-cycle arrest showed ongoing apoptosis in the HeLa cancer cells induced by compound 5e in concentration dependent manner. Additionally, generation of intracellular ROS along with the decrease in mitochondrial membrane potential supported that compound 5e caused oxidative stress resulting in apoptosis through mitochondria mediated pathway. Elevation in the level of cytochrome c and upregulation in expression of caspase-3 clearly indicated the involvement of the intrinsic pathway of programmed cell death. In brief; compound 5e could serve as a promising lead for the development of an effective antitumor agent.


Assuntos
Antineoplásicos/farmacologia , Azetidinas/farmacologia , Mitocôndrias/efeitos dos fármacos , Piperazina/farmacologia , Neoplasias do Colo do Útero/fisiopatologia , Antineoplásicos/síntese química , Antineoplásicos/química , Azetidinas/síntese química , Azetidinas/química , Caspase 3/genética , Caspase 3/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Feminino , Células HeLa , Humanos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Piperazina/análogos & derivados , Piperazina/síntese química , Espécies Reativas de Oxigênio/metabolismo , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo
18.
Cell Biol Int ; 42(9): 1141-1148, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29719086

RESUMO

Ladakh is an important part of the Trans-Himalayan region located between the Kunlun mountain range in the north and the main Great Himalayas to the south in the state of Jammu and Kashmir of India. The local cattle from Leh and Ladakh region, known as "Ladakhi cattle" is a unique germplasm having an excellent adaptation potential to high altitude hypobaric stress. In the present study, an effort was made to evaluate the transcriptional pattern of hypoxia inducing factor-1 (HIF-1) and several of its regulated genes in PBMCs of local Ladakhi cattle, Holstein Frisian crosses, Jersey (exotic) maintained at high altitude region and Sahiwal (Bos indicus) and Karan Fries (cross bred) cattle maintained in tropical environment. The combined data set indicated increased expression of HIF-1 and its regulated genes viz., glucose transporter 1 (GLUT1), vascular endothelial growth factor (VEGF), and hexokinase (HK2) in high altitude cattle indicating their importance in maintaining cellular homeostasis during high altitude hypoxia. The data indicated that hypoxia associated genes accumulated under hypoxic conditions are part of an essential adaptive component for adaptation to the high altitude of the trans-Himalayan region. In contrary, higher expression of molecular chaperons' viz., HSP70 and HSP90 in tropically adapted cattle give tolerance to high ambient temperature prevalent in tropical condition. In conclusion, HIF-1 and its regulatory genes could be termed as important candidates for producing homeostatic responses to hypoxia in cattle populations reared in higher altitudes of the Trans-Himalayan region.


Assuntos
Bovinos/genética , Hipóxia/genética , Altitude , Doença da Altitude/genética , Doença da Altitude/metabolismo , Doença da Altitude/veterinária , Animais , Pressão Atmosférica , Transportador de Glucose Tipo 1/genética , Proteínas de Choque Térmico HSP70/genética , Hexoquinase/genética , Temperatura Alta , Hipóxia/veterinária , Subunidade alfa do Fator 1 Induzível por Hipóxia/análise , Índia , Transcriptoma/genética , Fator A de Crescimento do Endotélio Vascular/genética
19.
Inorg Chem ; 57(24): 15112-15122, 2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-30475596

RESUMO

Here, we report the fabrication of a new Z-scheme based core/shell/shell heterostructure of NaNbO3/CuInS2/In2S3 (core/shell/shell) for photoelectrochemical (PEC) water splitting and also for degradation of organic pollutants. We have also performed a comparative study with a modified heterostructure of NaNbO3/In2S3/CuInS2 having Type II band alignment. The PEC measurements under visible light irradiation show increased photocatalytic performance for the NaNbO3/CuInS2/In2S3 heterostructures as revealed by a high current density of ∼6.72 mA/cm2 at -1.0 V versus Ag/AgCl and low photocurrent onset potential of ∼ -110 mV in comparison to the Type II system (∼1.63 mA/cm2 and -180 mV vs Ag/AgCl). Mott-Schottky plots confirmed the n-p-n type heterojunction formation in the NaNbO3/CuInS2/In2S3 heterostructure which reduces the charge carrier recombination (revealed by PL intensity and short lifetime). The Z-scheme based system also exhibits excellent degradation efficiency (∼99.6%) of organic pollutants. This work shows that the Z-scheme charge separation mechanism in NaNbO3/CuInS2/In2S3 nanostructures is more efficient than the Type II based on NaNbO3/In2S3/CuInS2.

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