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1.
Neural Comput ; 36(6): 1228-1244, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38669696

RESUMO

Deep learning (DL), a variant of the neural network algorithms originally proposed in the 1980s (Rumelhart et al., 1986), has made surprising progress in artificial intelligence (AI), ranging from language translation, protein folding (Jumper et al., 2021), autonomous cars, and, more recently, human-like language models (chatbots). All that seemed intractable until very recently. Despite the growing use of DL networks, little is understood about the learning mechanisms and representations that make these networks effective across such a diverse range of applications. Part of the answer must be the huge scale of the architecture and, of course, the large scale of the data, since not much has changed since 1986. But the nature of deep learned representations remains largely unknown. Unfortunately, training sets with millions or billions of tokens have unknown combinatorics, and networks with millions or billions of hidden units can't easily be visualized and their mechanisms can't be easily revealed. In this letter, we explore these challenges with a large (1.24 million weights VGG) DL in a novel high-density sample task (five unique tokens with more than 500 exemplars per token), which allows us to more carefully follow the emergence of category structure and feature construction. We use various visualization methods for following the emergence of the classification and the development of the coupling of feature detectors and structures that provide a type of graphical bootstrapping. From these results, we harvest some basic observations of the learning dynamics of DL and propose a new theory of complex feature construction based on our results.

2.
Mol Pharm ; 21(6): 2699-2712, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38747900

RESUMO

This study aims to encapsulate gemcitabine (GEM) using a phospholipid complex (PLC) in lipid nanoparticles (NPs) to achieve several desirable outcomes, including high drug loading, uniform particle size, improved therapeutic efficacy, and reduced toxicities. The successful preparation of GEM-loaded lipid NPs (GEM-NPs) was accomplished using the emulsification-solidification method, following optimization through Box-Behnken design. The size of the GEM-NP was 138.5 ± 6.7 nm, with a low polydispersity index of 0.282 ± 0.078, as measured by a zetasizer and confirmed by transmission electron and atomic force microscopy. GEM-NPs demonstrated sustained release behavior, surpassing the performance of the free GEM and phospholipid complex. Moreover, GEM-NPs exhibited enhanced cytotoxicity, apoptosis, and cell uptake in Panc-2 and Mia PaCa cells compared to the free GEM. The in vivo pharmacokinetics revealed approximately 4-fold higher bioavailability of GEM-NPs in comparison with free GEM. Additionally, the pharmacodynamic evaluation conducted in a DMBA-induced pancreatic cancer model, involving histological examination, serum IL-6 level estimation, and expression of cleaved caspase-3, showed the potential of GEM-NPs in the management of pancreatic cancer. Consequently, the lipid NP-based approach developed in our investigation demonstrates high stability and uniformity and holds promise for enhancing the therapeutic outcomes of GEM.


Assuntos
Desoxicitidina , Gencitabina , Nanopartículas , Neoplasias Pancreáticas , Fosfolipídeos , Desoxicitidina/análogos & derivados , Desoxicitidina/química , Desoxicitidina/farmacologia , Desoxicitidina/farmacocinética , Desoxicitidina/administração & dosagem , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Nanopartículas/química , Animais , Humanos , Linhagem Celular Tumoral , Fosfolipídeos/química , Camundongos , Tamanho da Partícula , Apoptose/efeitos dos fármacos , Portadores de Fármacos/química , Lipídeos/química , Liberação Controlada de Fármacos , Masculino , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/farmacocinética , Antimetabólitos Antineoplásicos/química , Antimetabólitos Antineoplásicos/farmacologia , Estabilidade de Medicamentos , Ratos , Lipossomos
3.
Bioorg Chem ; 147: 107378, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38643562

RESUMO

Alzheimer's disease (AD) is an enigmatic neurological illness that offers few treatment options. Recent exploration has highlighted the crucial connection of the Wnt signaling pathway in AD pathogenesis, shedding light on potential therapeutic targets. The present study focuses on the dual targeting of glycogen synthase kinase-3ß (GSK-3ß) and casein kinase-1δ (CK-1δ) within the framework of the Wnt signaling pathway as a possible technique for AD intervention. GSK-3ß and CK-1δ are multifunctional kinases known for their roles in tau hyperphosphorylation, amyloid processing, and synaptic dysfunction, all of which are major hallmarks of Alzheimer's disease. They are intricately linked to Wnt signaling, which plays a pivotal part in sustaining neuronal function and synaptic plasticity. Dysregulation of the Wnt pathway in AD contributes to cognitive decline and neurodegeneration. This review delves into the molecular mechanisms by which GSK-3ß and CK-1δ impact the Wnt signaling pathway, elucidating their roles in AD pathogenesis. We discuss the potential of small-molecule inhibitors along with their SAR studies along with the multi-targetd approach targeting GSK-3ß and CK-1δ to modulate Wnt signaling and mitigate AD-related pathology. In summary, the dual targeting of GSK-3ß and CK-1δ within the framework of the Wnt signaling pathway presents an innovative and promising avenue for future AD therapies, offering new hope for patients and caregivers in the quest to combat this challenging condition.


Assuntos
Doença de Alzheimer , Glicogênio Sintase Quinase 3 beta , Via de Sinalização Wnt , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Humanos , Via de Sinalização Wnt/efeitos dos fármacos , Glicogênio Sintase Quinase 3 beta/metabolismo , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Caseína Quinase Idelta/antagonistas & inibidores , Caseína Quinase Idelta/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Estrutura Molecular , Animais , Relação Estrutura-Atividade
4.
J Chem Phys ; 160(17)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38747997

RESUMO

Functionalization of perovskite nanocrystal surfaces with thiocyanate anions presents a transformative approach to enhancing stability and photoluminescence quantum yield (PLQY) through surface defect passivation. This study investigates the role of thiocyanate ligands in modifying the optoelectronic properties of CsPbBr3 nanocrystals. We employed ultrafast two-dimensional infrared spectroscopy to investigate the nature of the dynamic interaction of thiocyanate ligands with nanocrystal surfaces, providing insights into the mechanisms underlying the observed increase in PLQY and stability. Our analysis reveals that the thiocyanate ligands efficiently passivate the surface defects, thereby enhancing the PLQY and the stability of the treated nanocrystals. The spectroscopic evidence supports a model where thiocyanate binds to under-coordinated lead atoms, contributing to a stable nanocrystal surface with enhanced optoelectronic performance. This ligand-induced passivation mechanism advances our understanding of surface chemistry's role in optimizing nanomaterials for solar cell and LED applications.

5.
Mol Pharm ; 20(1): 524-544, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36306447

RESUMO

Breast cancer leads to the highest mortality among women resulting in a major clinical burden. Multidrug therapy is more efficient in such patients compared to monodrug therapy. Simultaneous combinatorial or co-delivery garnered significant interest in the past years. Caffeic acid (CFA) (a natural polyphenol) has received growing attention because of its anticarcinogenic and antioxidant potential. Bortezomib (BTZ) is a proteasome inhibitor and may be explored for treating breast cancer. Despite its high anticancer activity, the low water solubility and chemical instability restrict its efficacy against solid tumors. In the present study, we designed and investigated a HP-PCL (N-2-hydroxypropylmethacrylamide-polycaprolactone) polymeric micellar (PMCs) system for the simultaneous delivery of BTZ and CFA in the treatment of breast cancer. The designed BTZ+CFA-HP-PCL PMCs were fabricated, optimized, and characterized for size, zeta potential, surface morphology, and in vitro drug release. Developed nanosized (174.6 ± 0.24 nm) PMCs showed enhanced cellular internalization and cell cytotoxicity in both MCF-7 and MDA-MB-231 cells. ROS (reactive oxygen species) levels were highest in BTZ-HP-PCL PMCs, while CFA-HP-PCL PMCs significantly (p < 0.001) scavenged the ROS generated in 2',7'-dichlorofluorescein diacetate (DCFH-DA) assay. The mitochondrial membrane potential (MMP) assay revealed intense and significant green fluorescence in both types of cancer cells when treated with BTZ-HP-PCL PMCs (p < 0.001) indicating apoptosis or cell death. The pharmacokinetic studies revealed that BTZ-HP-PCL PMCs and BTZ+CFA-HP-PCL PMCs exhibited the highest bioavailability, enhanced plasma half-life, decreased volume of distribution, and lower clearance rate than the pure combination of drugs. In the organ biodistribution studies, the combination of BTZ+CFA showed higher distribution in the spleen and the heart. Overall findings of in vitro studies surprisingly resulted in better therapeutic efficiency of BTZ-HP-PCL PMCs than BTZ+CFA-HP-PCL PMCs. However, the in vivo tumor growth inhibition study performed in tumor-induced mice concluded that the tumor growth was inhibited by both BTZ-HP-PCL PMCs and BTZ+CFA-HP-PCL PMCs (p < 0.0001) more efficiently than pure BTZ and the combination (BTZ+CFA), which may be due to the conversion of boronate ester into boronic acid. Henceforth, the combination of BTZ and CFA provides further indications to be explored in the future to support the hypothesis that BTZ may work with polyphenol (CFA) in the acidic environment of the tumor.


Assuntos
Antineoplásicos , Inibidores de Proteassoma , Feminino , Camundongos , Animais , Inibidores de Proteassoma/farmacologia , Inibidores de Proteassoma/uso terapêutico , Micelas , Espécies Reativas de Oxigênio , Distribuição Tecidual , Quimioterapia Combinada , Hansenostáticos/uso terapêutico , Bortezomib/farmacologia , Bortezomib/química , Polímeros/química , Linhagem Celular Tumoral , Antineoplásicos/química
6.
Eur Radiol ; 33(9): 6582-6591, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37042979

RESUMO

OBJECTIVES: While fully supervised learning can yield high-performing segmentation models, the effort required to manually segment large training sets limits practical utility. We investigate whether data mined line annotations can facilitate brain MRI tumor segmentation model development without requiring manually segmented training data. METHODS: In this retrospective study, a tumor detection model trained using clinical line annotations mined from PACS was leveraged with unsupervised segmentation to generate pseudo-masks of enhancing tumors on T1-weighted post-contrast images (9911 image slices; 3449 adult patients). Baseline segmentation models were trained and employed within a semi-supervised learning (SSL) framework to refine the pseudo-masks. Following each self-refinement cycle, a new model was trained and tested on a held-out set of 319 manually segmented image slices (93 adult patients), with the SSL cycles continuing until Dice score coefficient (DSC) peaked. DSCs were compared using bootstrap resampling. Utilizing the best-performing models, two inference methods were compared: (1) conventional full-image segmentation, and (2) a hybrid method augmenting full-image segmentation with detection plus image patch segmentation. RESULTS: Baseline segmentation models achieved DSC of 0.768 (U-Net), 0.831 (Mask R-CNN), and 0.838 (HRNet), improving with self-refinement to 0.798, 0.871, and 0.873 (each p < 0.001), respectively. Hybrid inference outperformed full image segmentation alone: DSC 0.884 (Mask R-CNN) vs. 0.873 (HRNet), p < 0.001. CONCLUSIONS: Line annotations mined from PACS can be harnessed within an automated pipeline to produce accurate brain MRI tumor segmentation models without manually segmented training data, providing a mechanism to rapidly establish tumor segmentation capabilities across radiology modalities. KEY POINTS: • A brain MRI tumor detection model trained using clinical line measurement annotations mined from PACS was leveraged to automatically generate tumor segmentation pseudo-masks. • An iterative self-refinement process automatically improved pseudo-mask quality, with the best-performing segmentation pipeline achieving a Dice score of 0.884 on a held-out test set. • Tumor line measurement annotations generated in routine clinical radiology practice can be harnessed to develop high-performing segmentation models without manually segmented training data, providing a mechanism to rapidly establish tumor segmentation capabilities across radiology modalities.


Assuntos
Neoplasias Encefálicas , Processamento de Imagem Assistida por Computador , Adulto , Humanos , Processamento de Imagem Assistida por Computador/métodos , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Neoplasias Encefálicas/diagnóstico por imagem , Encéfalo/diagnóstico por imagem
7.
J Biochem Mol Toxicol ; 37(5): e23321, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36808794

RESUMO

Vascular endothelial growth factor receptor-2 (VEGFR-2) is crucial in promoting tumor angiogenesis and cancer metastasis. Thus, inhibition of VEGFR-2 has appeared as a good tactic for cancer treatment. To find out novel VEGFR-2 inhibitors, first, the PDB structure of VEGFR-2, 6GQO, was selected based on atomic nonlocal environment assessment (ANOLEA) and PROCHECK assessment. 6GQO was then further used for structure-based virtual screening (SBVS) of different molecular databases, including US-FDA approved drugs, US-FDA withdrawn drugs, may bridge, MDPI, and Specs databases using Glide. Based on SBVS, receptor fit, drug-like filters, and absorption, distribution, metabolism, excretion, and toxicity (ADMET) analysis of 427877 compounds, the best 22 hits were selected. From the 22 hits, hit 5 complex with 6GQO was put through molecular mechanics/generalized born surface area (MM/GBSA) study and hERG binding. The MM/GBSA study revealed that hit 5 possesses lesser binding free energy with more inferior stability in the receptor pocket than the reference compound. The VEGFR-2 inhibition assay of hit 5 disclosed an IC50 of 165.23 nM against VEGFR-2, which can be possibly enhanced through structural modifications.


Assuntos
Inibidores de Proteínas Quinases , Receptor 2 de Fatores de Crescimento do Endotélio Vascular , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Inibidores de Proteínas Quinases/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Neoplasias/tratamento farmacológico
8.
J Liposome Res ; : 1-25, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37594466

RESUMO

The object of the current study was to develop and evaluate trastuzumab-conjugated Paclitaxel (PTX) and Elacridar (ELA)-loaded PEGylated pH-sensitive liposomes (TPPLs) for site-specific delivery of an anticancer drug. In this study, paclitaxel is used as an anticancer drug which promotes microtubules polymerization and arrest cell cycle progression at mitosis and subsequently leading to cell death. The single use of PTX causes multiple drug resistance (MDR) and results failure of the therapy. Hence, the combination of PTX and P-glycoprotein inhibitor (ELA) are used to achieve maximum therapeutic effects of PTX. Moreover, monoclonal antibody (trastuzumab) is used as ligand for the targeting the drug bearing carriers to BC. Thus, trastuzumab anchored pH-sensitive liposomes bearing PTX and ELA were developed using thin film hydration method and Box-Behnken Design (BBD) for optimizing various formulation variables. The optimized liposomes undergo characterization such as vesicle size, PDI, and zeta potential, which were observed to be 122 ± 2.14 nm, 0.224, and -15.5 mV for PEGylated pH-sensitive liposomes (PEG-Ls) and 134 ± 1.88 nm, 0.238, and -13.98 mV for TPPLs, respectively. The results of the in vitro drug release study of both formulations (PEG-Ls and TPPLs) showed enhanced percentage drug release at an acidic pH 5 as compared to drug release at a physiological pH 7.4. Further, the in vitro cytotoxicity studies were performed in the SK-BR-3 and MDA-MB-231 cell lines. The cellular uptake study of FITC-loaded TPPLs in SK-BR-3 cells showed greater uptake than FITC-loaded PEG-Ls, while in MDA-MB-231 cells there was no significant difference in cell uptake between FITC-loaded TPPLs and FITC-loaded PEG-Ls. Hence, it can be concluded that the HER-2 overexpressing cancer cell line (SK-BR-3) was showed better cytotoxicity and cell uptake of TPPLs than the cells that expressed low levels of HER2 (MDA-MB-231). The in vivo tumor regression study, TPPLs showed significantly more tumor burden reduction i.e. up ∼74% as compared to other liposomes after 28 days. Furthermore, the in vivo studies of TPPLs showed a minimal toxicity profile, minimal hemolysis, higher tumor tissue distribution, and superior antitumor efficacy as compared to other formulations. These studies confirmed that TPPLs are a safe and efficacious treatment for breast cancer.

9.
Int J Mol Sci ; 24(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38069227

RESUMO

Sexual differentiation is an important developmental phenomenon in cucurbits that directly affects fruit yield. The natural existence of multiple flower types in melon offers an inclusive structure for studying the molecular basis of sexual differentiation. The current study aimed to identify and characterize the molecular network involved in sex determination and female development in melon. Male and female pools separated by the F2 segregated generation were used for sequencing. The comparative multi-omics data revealed 551 DAPs and 594 DEGs involved in multiple pathways of melon growth and development, and based on functional annotation and enrichment analysis, we summarized four biological process modules, including ethylene biosynthesis, flower organ development, plant hormone signaling, and ubiquitinated protein metabolism, that are related to female development. Furthermore, the detailed analysis of the female developmental regulatory pathway model of ethylene biosynthesis, signal transduction, and target gene regulation identified some important candidates that might have a crucial role in female development. Two CMTs ((cytosine-5)-methyltransferase), one AdoHS (adenosylhomocysteinase), four ACSs (1-aminocyclopropane-1-carboxylic acid synthase), three ACOs (ACC oxidase), two ARFs (auxin response factor), four ARPs (auxin-responsive protein), and six ERFs (Ethylene responsive factor) were identified based on various female developmental regulatory models. Our data offer new and valuable insights into female development and hold the potential to offer a deeper comprehension of sex differentiation mechanisms in melon.


Assuntos
Cucurbitaceae , Redes Reguladoras de Genes , Multiômica , Etilenos/metabolismo , Ácidos Indolacéticos , Regulação da Expressão Gênica de Plantas , Frutas/metabolismo
10.
AAPS PharmSciTech ; 24(7): 180, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37697085

RESUMO

Ferroptosis, a pathway dependent on oxygen and iron catalysts, holds promise as a therapeutic approach for cancer treatment due to its manageable regulation, direct control, and immunogenic properties. The sensitivity of cancer cells to ferroptosis induction varies based on their metabolic, genetic, and signalling pathways, prompting the use of combination therapy. In this study, we conducted a screening of drug combinations, including sorafenib (SOR) with simvastatin (SIM), phenethyl isothiocyanate, and trigonelline, in MDA-MB-231, A549, and HeLa cells to assess their cytotoxicity. The SOR-SIM combination exhibited a synergistic effect in MDA-MB-231, A549, and HeLa cells, with calculated CI values of ~ 0.66, 0.53, and 0.59, respectively. Furthermore, co-treatment with ferrostatin-1 resulted in a concentration-dependent increase in the IC50 values. Additionally, SOR + SIM demonstrated a significant reduction in GSH levels, an increase in MDA levels, and mitochondrial membrane depolarization across all three cell lines, indicating their ferroptosis inducing potential. In-vivo studies showed a significant reduction in tumor volume by 3.53-, 2.55-, and 1.47-fold compared to control, SIM, and SOR, respectively. Toxicity assessments revealed insignificant changes in biomarker levels and no observable deformations in isolated organs, except for erythrocyte shrinkage and membrane scrambling effects caused by the SOR + SIM combination. Overall, our findings highlight the potential of the SOR + SIM combination as an effective strategy for cancer treatment, emphasizing the importance of further research in targeted drug delivery systems to ensure its safety.


Assuntos
Ferroptose , Neoplasias , Humanos , Detecção Precoce de Câncer , Células HeLa , Sorafenibe/farmacologia , Sistemas de Liberação de Medicamentos , Neoplasias/tratamento farmacológico
11.
Radiology ; 303(1): 80-89, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35040676

RESUMO

Background Artificial intelligence (AI) applications for cancer imaging conceptually begin with automated tumor detection, which can provide the foundation for downstream AI tasks. However, supervised training requires many image annotations, and performing dedicated post hoc image labeling is burdensome and costly. Purpose To investigate whether clinically generated image annotations can be data mined from the picture archiving and communication system (PACS), automatically curated, and used for semisupervised training of a brain MRI tumor detection model. Materials and Methods In this retrospective study, the cancer center PACS was mined for brain MRI scans acquired between January 2012 and December 2017 and included all annotated axial T1 postcontrast images. Line annotations were converted to boxes, excluding boxes shorter than 1 cm or longer than 7 cm. The resulting boxes were used for supervised training of object detection models using RetinaNet and Mask region-based convolutional neural network (R-CNN) architectures. The best-performing model trained from the mined data set was used to detect unannotated tumors on training images themselves (self-labeling), automatically correcting many of the missing labels. After self-labeling, new models were trained using this expanded data set. Models were scored for precision, recall, and F1 using a held-out test data set comprising 754 manually labeled images from 100 patients (403 intra-axial and 56 extra-axial enhancing tumors). Model F1 scores were compared using bootstrap resampling. Results The PACS query extracted 31 150 line annotations, yielding 11 880 boxes that met inclusion criteria. This mined data set was used to train models, yielding F1 scores of 0.886 for RetinaNet and 0.908 for Mask R-CNN. Self-labeling added 18 562 training boxes, improving model F1 scores to 0.935 (P < .001) and 0.954 (P < .001), respectively. Conclusion The application of semisupervised learning to mined image annotations significantly improved tumor detection performance, achieving an excellent F1 score of 0.954. This development pipeline can be extended for other imaging modalities, repurposing unused data silos to potentially enable automated tumor detection across radiologic modalities. © RSNA, 2022 Online supplemental material is available for this article.


Assuntos
Inteligência Artificial , Redes Neurais de Computação , Encéfalo , Humanos , Imageamento por Ressonância Magnética , Estudos Retrospectivos
12.
Microb Pathog ; 169: 105665, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35781005

RESUMO

Urinary tract infections (UTIs) are a serious health concern worldwide. Treatment of UTIs is becoming a challenge as uropathogenic Escherichia coli (UPEC), which is the most common etiological agent, has developed resistance to the main classes of antibiotics. Small molecules that interfere with metabolic processes rather than growth are attractive alternatives to conventional antibiotics. Repurposing of already known drugs for treating infectious diseases could be an attractive avenue for finding novel therapeutics against infections caused by UPEC. Virtual screenings enable the rapid and economical identification of target ligands from large libraries of compounds, reducing the cost and time of traditional drug discovery. Moreover, the drugs that have been approved by the FDA have low cytotoxicity and good pharmacological characteristics. In this work, we targeted the HisC enzyme of the histidine biosynthetic pathway as enzymes of this pathway are absent in humans. We screened the library of FDA-approved drugs against HisC via molecular docking, and four hits (Docetaxel, Suramin, Digitoxin, and Nystatin) showing the highest binding energy were selected. These were further tested for antibacterial activity, which was observed only for Docetaxel (MIC value of 640 µg/ml); therefore, Docetaxel was further tested for its efficacy in vivo in murine catheter UTI model and antibiofilm activity using crystal violet staining and scanning electron microscopy. Docetaxel inhibited biofilm formation and reduced the bacterial load in urine, kidney, and bladder. Docking studies revealed that Docetaxel acts by blocking the binding site of HisC to the native substrate by competitive inhibition. Docetaxel may be a potential new inhibitor for UPEC with antibacterial and antibiofilm capability.


Assuntos
Infecções por Escherichia coli , Infecções Urinárias , Escherichia coli Uropatogênica , Animais , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Docetaxel/metabolismo , Reposicionamento de Medicamentos , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Humanos , Camundongos , Simulação de Acoplamento Molecular , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/microbiologia
13.
Pediatr Transplant ; 26(8): e14401, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36177941

RESUMO

BACKGROUND: Immediate extubation is integral constituent of enhance recovery protocols. Purpose of this study was to examine success rates and safety of protocolized immediate extubation in pediatric living donor liver transplant recipients and to find out factors associated with non-immediate extubation in operation room. METHODS: We performed retrospective analysis for data of small (≤20 kg) pediatric patients transplanted between 2017 and 2019 (protocolized duration) and compared with data of transplants done between 2014 and 2016 (non-protocolized duration). Further, we compared data during each time duration between immediate extubation and non-immediate extubation group to find risk factors in that particular duration. RESULTS: Immediate extubation rates were significantly higher during protocolized duration compared with non-protocolized duration (85.52% vs. 48.29%, p < .001). Reintubation rates decreased during protocolized duration (10.9% vs. 4.6%). Hospital stays (20.47 ± 7.06 vs. 27.8 ± 6.2 days, p < .001) and mortality (13.2% vs. 28%, p = .04) were significantly decreased in protocolized duration. Higher age (OR: 2.85, 95% CI 1.22-6.67, p = .02), weight > 10 (OR: 4.37, 95% CI 1.16-16.46, p = .029) and high vasopressor support (OR: 32, 95% CI 6.4-160.13, p < .001) found as significant predictors of non-immediate extubation however only high vasopressor support found to be independent predictor during protocolized duration. CONCLUSIONS: Outcomes in pediatric transplants can be optimized by immediate extubation in majority of cases when protocolized as part of policy.


Assuntos
Extubação , Transplante de Fígado , Humanos , Criança , Extubação/efeitos adversos , Extubação/métodos , Transplante de Fígado/métodos , Doadores Vivos , Estudos Retrospectivos , Estudos de Viabilidade , Tempo de Internação
14.
Int J Mol Sci ; 23(3)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35163430

RESUMO

Tomato spotted wilt virus impacts negatively on a wide range of economically important plants, especially tomatoes. When plants facing any pathogen attack or infection, increase the transcription level of plant genes that are produced pathogenesis-related (PR) proteins. The aim of this study is a genome-wide identification of PR-10 superfamily and comparative analysis of PR-10 and Sw-5b gene functions against tomato responses to biotic stress (TSWV) to systemic resistance in tomato. Forty-five candidate genes were identified, with a length of 64-210 amino acid residues and a molecular weight of 7.6-24.4 kDa. The PR-10 gene was found on ten of the twelve chromosomes, and it was determined through a genetic ontology that they were involved in six biological processes and molecular activities, and nine cellular components. Analysis of the transcription level of PR-10 family members showed that the PR-10 gene (Solyc09g090980) has high expression levels in some parts of the tomato plant. PR-10 and Sw-5b gene transcription and activity in tomato leaves were strongly induced by TSWV infection, whereas H8 plants having the highest significantly upregulated expression of PR-10 and Sw-5b gene after the inoculation of TSWV, and TSWV inoculated in M82 plants showed significantly upregulated expression of PR-10 gene comparatively lower than H8 plants. There was no significant expression of Sw-5b gene of TSWV inoculated in M82 plants and then showed highly significant correlations between PR-10 and Sw-5b genes at different time points in H8 plants showed significant correlations compared to M82 plants after the inoculation of TSWV; a heat map showed that these two genes may also participate in regulating the defense response after the inoculation of TSWV in tomato.


Assuntos
Resistência à Doença , Proteínas de Plantas/genética , Análise de Sequência de DNA/métodos , Solanum lycopersicum/crescimento & desenvolvimento , Tospovirus/patogenicidade , Mapeamento Cromossômico , Evolução Molecular , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Solanum lycopersicum/genética , Solanum lycopersicum/virologia , Modelos Moleculares , Família Multigênica , Filogenia , Proteínas de Plantas/química , Conformação Proteica , Distribuição Tecidual , Regulação para Cima
15.
Anal Chem ; 93(16): 6456-6462, 2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33861566

RESUMO

Rapid point-of-care (POC) quantification of low virus RNA load would significantly reduce the turn-around time for the PCR test and help contain a fast-spreading epidemic. Herein, we report a droplet digital PCR (ddPCR) platform that can achieve this sensitivity and rapidity without bulky lab-bound equipment. The key technology is a flattened pipette tip with an elliptical cross-section, which extends a high aspect-ratio microfluidic chip design to pipette scale, for rapid (<5 min) generation of several thousand monodispersed droplets ∼150 to 350 µm in size with a CV of ∼2.3%. A block copolymer surfactant (polyoxyalkylene F127) is used to stabilize these large droplets in oil during thermal cycling. At this droplet size and number, positive droplets can be counted by eye or imaged by a smartphone with appropriate illumination/filtering to accurately quantify up to 100 target copies. We demonstrate with 2019 nCoV-PCR assay LODs of 3.8 copies per 20 µL of sample and a dynamic range of 4-100 copies. The ddPCR platform is shown to be inhibitor resistant with spiked saliva samples, suggesting RNA extraction may not be necessary. It represents a rapid 1.5-h POC quantitative PCR test that requires just a pipette equipped with elliptical pipette tip, a commercial portable thermal cycler, a smartphone, and a portable trans-illuminator, without bulky and expensive micropumps and optical detectors that prevent POC application.


Assuntos
COVID-19 , Sistemas Automatizados de Assistência Junto ao Leito , Humanos , Reação em Cadeia da Polimerase em Tempo Real , SARS-CoV-2 , Carga Viral
16.
Microb Pathog ; 154: 104792, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33636321

RESUMO

Acylated homoserine lactones (AHL) such as N-(3-oxododecanoyl)-l-homoserine lactone (3-oxo-C12 HSL) and N-butyryl-l-homoserine lactone (C4 HSL) are the most common autoinducer molecules in Pseudomonas aeruginosa. These AHL molecules not only regulate the expression of virulence factors but also have been shown to interfere with the host cell and modulate its functions. Recently, we reported that 3-oxo-C12 HSL but not C4 HSL causes cytosolic Ca2+ rise and ROS production in platelets. In this study, we examined the potential of AHLs to induce apoptosis in the human blood platelet. Our result showed that 3-oxo-C12 HSL but not C4 HSL causes phosphatidylserine (PS) exposure, mitochondrial dysfunction (mitochondrial transmembrane potential loss, and mitochondrial permeability transition pore (mPTP) formation). Besides, 3-oxo-C12 HSL also inhibited thrombin-induced platelet aggregation and clot retraction. The pretreatment of an intracellular calcium chelator BAPTA-AM or ROS inhibitor (DPI) significantly attenuated the 3-oxo-C12 HSL induced apoptotic characters such as PS exposure and mitochondrial dysfunctions. These data, including our previous findings, confirmed that 3-oxo-C12 HSL induced intracellular Ca2+ mediated ROS production results in the activation and subsequent induction of apoptotic features in platelets. Our results demonstrated that the 3-oxo-C12 HSL modulates the functions of platelets that may cause severe thrombotic complications in P. aeruginosa infected individuals.


Assuntos
Plaquetas , Cálcio , 4-Butirolactona/análogos & derivados , Apoptose , Homosserina/análogos & derivados , Humanos , Lactonas , Pseudomonas aeruginosa , Espécies Reativas de Oxigênio
17.
Clin Transplant ; 35(5): e14271, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33638186

RESUMO

BACKGROUND: Continuous Renal Replacement Therapy (CRRT) is often used to support the intraoperative course during liver transplantation (LT) for patients with HRS. However, the use of intraoperative CRRT (IOCRRT) is not without its problems. Living donor liver transplantation (LDLT) is a planned operation and is possible without IOCRRT as the recipient can be optimized. AIM: To study the peritransplant outcomes of patients with CLD and HRS undergoing LT without IOCRRT. METHODS: Analysis of LT program database for perioperative outcomes in patients with HRS from Feb 2017 to Dec 2018. RESULTS: 87/363 (23.9%) adult LDLT patients had HRS, of whom 31 (35.6%) did not respond (NR) to standard medical therapy (SMT) prior to LT. Modified perioperative protocol enabled the NR patients (who were sicker and in persistent renal failure) to undergo LT without IOCRRT. Postoperative renal dysfunction was similar (2 in NR and 2 in R) at 1 year. Post-LT survival was also not different at one month (83.87% in NR and 87.5% in R [p = .640]) and at 1 year (77% in NR vs 80.4% in non-responders [p = .709]). CONCLUSION: IOCRRT can be avoided in HRS patients undergoing LDLT without compromising their outcomes (post-LT survival and RD), even in patients who have not responded to SMT, preoperatively.


Assuntos
Síndrome Hepatorrenal , Transplante de Fígado , Transplantes , Adulto , Humanos , Doadores Vivos , Terapia de Substituição Renal , Resultado do Tratamento
18.
Int J Mol Sci ; 22(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34445115

RESUMO

The SWEET (Sugars Will Eventually be Exported Transporter) proteins are a novel family of sugar transporters that play key roles in sugar efflux, signal transduction, plant growth and development, plant-pathogen interactions, and stress tolerance. In this study, 22 ClaSWEET genes were identified in Citrullus lanatus (Thunb.) through homology searches and classified into four groups by phylogenetic analysis. The genes with similar structures, conserved domains, and motifs were clustered into the same groups. Further analysis of the gene promoter regions uncovered various growth, development, and biotic and abiotic stress responsive cis-regulatory elements. Tissue-specific analysis showed most of the genes were highly expressed in male flowers and the roots of cultivated varieties and wild cultivars. In addition, qRT-PCR results further imply that ClaSWEET proteins might be involved in resistance to Fusarium oxysporum infection. Moreover, a significantly higher expression level of these genes under various abiotic stresses suggests its multifaceted role in mediating plant responses to drought, salt, and low-temperature stress. The genome-wide characterization and phylogenetic analysis of ClaSWEET genes, together with the expression patterns in different tissues and stimuli, lays a solid foundation for future research into their molecular function in watermelon developmental processes and responses to biotic and abiotic stresses.


Assuntos
Transporte Biológico/genética , Citrullus/genética , Genoma de Planta/genética , Família Multigênica/genética , Proteínas de Plantas/genética , Estresse Fisiológico/genética , Açúcares/metabolismo , Fusarium/genética , Regulação da Expressão Gênica de Plantas/genética , Estudo de Associação Genômica Ampla/métodos , Filogenia , Raízes de Plantas/genética , Regiões Promotoras Genéticas/genética
19.
Phys Chem Chem Phys ; 22(37): 21360-21368, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32940303

RESUMO

Two-dimensional covalent organic frameworks (2D-COFs) belong to a new class of molecular materials that have attracted huge attention in recent years due to their analogous nature to graphene. In this work, we present a systematic study of the electronic structure, carrier mobility and work function of imine based 2D-COFs. We identify these 2D-COFs as a new class of semiconducting materials with tunable electronic/optoelectronic properties and significant mobility. The results show that by rationally doping 2D-COFs at the molecular level, it is possible to control their structural and optoelectronic responses. Cohesive energy calculations revealed that all the studied 2D-COFs are thermodynamically stable. Also, the calculated binding energy of 2D-COFs on HOPG was found to be less than 1 eV, which indicates that the COFs do not interact strongly with HOPG, and it will not affect their electronic properties. Additionally, we have synthesized a 2,4,6-pyrimidinetriamine based 2D-COF and experimentally measured its band gap using scanning tunnelling spectroscopy. The experimentally measured band gap is found to be in good agreement with theoretical results.

20.
Int J Mol Sci ; 21(3)2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32041336

RESUMO

Members of the plant-specific GASA (gibberellic acid-stimulated Arabidopsis) gene family have multiple potential roles in plant growth and development, particularly in flower induction and seed development. However, limited information is available about the functions of these genes in fruit plants, particularly in grapes. We identified 14 GASA genes in grapevine (Vitis vinifera L.) and performed comprehensive bioinformatics and expression analyses. In the bioinformatics analysis, the locations of genes on chromosomes, physiochemical properties of proteins, protein structure, and subcellular positions were described. We evaluated GASA proteins in terms of domain structure, exon-intron distribution, motif arrangements, promoter analysis, phylogenetic, and evolutionary history. According to the results, the GASA domain is conserved in all proteins and the proteins are divided into three well-conserved subgroups. Synteny analysis proposed that segmental and tandem duplication have played a role in the expansion of the GASA gene family in grapes, and duplicated gene pairs have negative selection pressure. Most of the proteins were predicted to be in the extracellular region, chloroplasts, and the vacuole. In silico promoter analysis suggested that the GASA genes may influence different hormone signaling pathways and stress-related mechanisms. Additionally, we performed a comparison of the expression between seedless (Thompson seedless) and seeded (Red globe) cultivars in different plant parts, including the ovule during different stages of development. Furthermore, some genes were differentially expressed in different tissues, signifying their role in grapevine growth and development. Several genes (VvGASA2 and 7) showed different expression levels in later phases of seed development in Red globe and Thompson seedless, suggesting their involvement in seed development. Our study presents the first genome-wide identification and expression profiling of grapevine GASA genes and provides the basis for functional characterization of GASA genes in grapes. We surmise that this information may provide new potential resources for the molecular breeding of grapes.


Assuntos
Biologia Computacional/métodos , Perfilação da Expressão Gênica/métodos , Proteínas de Plantas/genética , Vitis/crescimento & desenvolvimento , Mapeamento Cromossômico/métodos , Evolução Molecular , Regulação da Expressão Gênica de Plantas , Modelos Moleculares , Família Multigênica , Filogenia , Proteínas de Plantas/química , Regiões Promotoras Genéticas , Conformação Proteica , Sementes/genética , Sementes/crescimento & desenvolvimento , Sintenia , Vitis/genética
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