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1.
Front Mol Biosci ; 11: 1346242, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38567100

RESUMO

Esophageal cancer (EC) remains a significant health challenge globally, with increasing incidence and high mortality rates. Despite advances in treatment, there remains a need for improved diagnostic methods and understanding of disease progression. This study addresses the significant challenges in the automatic classification of EC, particularly in distinguishing its primary subtypes: adenocarcinoma and squamous cell carcinoma, using histopathology images. Traditional histopathological diagnosis, while being the gold standard, is subject to subjectivity and human error and imposes a substantial burden on pathologists. This study proposes a binary class classification system for detecting EC subtypes in response to these challenges. The system leverages deep learning techniques and tissue-level labels for enhanced accuracy. We utilized 59 high-resolution histopathological images from The Cancer Genome Atlas (TCGA) Esophageal Carcinoma dataset (TCGA-ESCA). These images were preprocessed, segmented into patches, and analyzed using a pre-trained ResNet101 model for feature extraction. For classification, we employed five machine learning classifiers: Support Vector Classifier (SVC), Logistic Regression (LR), Decision Tree (DT), AdaBoost (AD), Random Forest (RF), and a Feed-Forward Neural Network (FFNN). The classifiers were evaluated based on their prediction accuracy on the test dataset, yielding results of 0.88 (SVC and LR), 0.64 (DT and AD), 0.82 (RF), and 0.94 (FFNN). Notably, the FFNN classifier achieved the highest Area Under the Curve (AUC) score of 0.92, indicating its superior performance, followed closely by SVC and LR, with a score of 0.87. This suggested approach holds promising potential as a decision-support tool for pathologists, particularly in regions with limited resources and expertise. The timely and precise detection of EC subtypes through this system can substantially enhance the likelihood of successful treatment, ultimately leading to reduced mortality rates in patients with this aggressive cancer.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38010481

RESUMO

A non-invasive optical technique known as photoplethysmography (PPG) can be used to provide various physiological measurements and estimations. PPG can be used to assess cardiovascular disease (CVD). Hypertension is a primary risk factor for CVD and a major health problem worldwide. PPG is popular because of its important applications in the evaluation of cardiac activity, variations in venous blood volume, blood oxygen saturation, blood pressure and heart rate variability, etc. In this study, we provide a comprehensive analysis of the extraction of various physiological parameters using PPG waveforms. In addition, we focused on the role of machine learning (ML) models used for the estimation of blood pressure and hypertension classification based on PPG waveforms to make future research and innovation recommendations. This study will be helpful for researchers, scientists, and medical practitioners working on PPG waveforms for monitoring, screening, and diagnosis, as a comparative study or reference.

3.
Cells ; 11(22)2022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36429092

RESUMO

Cardiovascular diseases (CVDs) are one of the leading causes of death worldwide. Accumulating evidences have highlighted the importance of exosomes and non-coding RNAs (ncRNAs) in cardiac physiology and pathology. It is in general consensus that exosomes and ncRNAs play a crucial role in the maintenance of normal cellular function; and interestingly it is envisaged that their potential as prospective therapeutic candidates and biomarkers are increasing rapidly. Considering all these aspects, this review provides a comprehensive overview of the recent understanding of exosomes and ncRNAs in CVDs. We provide a great deal of discussion regarding their role in the cardiovascular system, together with providing a glimpse of ideas regarding strategies exploited to harness their potential as a therapeutic intervention and prospective biomarker against CVDs. Thus, it could be envisaged that a thorough understanding of the intricacies related to exosomes and ncRNA would seemingly allow their full exploration and may lead clinical settings to become a reality in near future.


Assuntos
Doenças Cardiovasculares , Sistema Cardiovascular , Exossomos , Humanos , Exossomos/genética , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/terapia , RNA não Traduzido/genética , Biomarcadores
4.
Commun Biol ; 2: 470, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31872075

RESUMO

An exacerbated amount of neutrophil extracellular traps (NETs) can cause dysfunction of systems during inflammation. However, host proteins and factors that suppress NET formation (NETosis) are not clearly identified. Here we show that an innate immune collectin, pulmonary surfactant protein-D (SP-D), attenuates lipopolysaccharide (LPS)-mediated NETosis in human neutrophils by binding to LPS. SP-D deficiency in mice (Sftpd-/-) leads to excess NET formation in the lungs during LPS-mediated inflammation. In the absence of SP-D, NETs inhibit the surface-active properties of lung surfactant, essential to prevent the collapse of alveoli, the air breathing structures of the lungs. SP-D reverses NET-mediated inhibition of surfactant and restores the biophysical properties of surfactant. To the best of our knowledge, this study establishes for the first time that (i) SP-D suppresses LPS-mediated NETosis, (ii) NETs inhibit pulmonary surfactant function in the absence of SP-D, and (iii) SP-D can restore NET-mediated inhibition of the surfactant system.


Assuntos
Armadilhas Extracelulares/imunologia , Armadilhas Extracelulares/metabolismo , Lipopolissacarídeos/imunologia , Neutrófilos/imunologia , Neutrófilos/metabolismo , Proteína D Associada a Surfactante Pulmonar/metabolismo , Animais , Histonas/metabolismo , Humanos , Camundongos , Camundongos Knockout , Modelos Animais , Imagem Molecular , Substâncias Protetoras , Surfactantes Pulmonares/metabolismo
5.
Artigo em Inglês | MEDLINE | ID: mdl-25125975

RESUMO

Chronic obstructive pulmonary disease (COPD) is a major global health problem. It results from chronic inflammation and causes irreversible airway damage. Levels of different serum cytokines could be surrogate biomarkers for inflammation and lung function in COPD. We aimed to determine the serum levels of different biomarkers in COPD patients, the association between cytokine levels and various prognostic parameters, and the key pathways/networks involved in stable COPD. In this study, serum levels of 48 cytokines were examined by multiplex assays in 30 subjects (control, n=9; COPD, n=21). Relationships between serum biomarkers and forced expiratory volume in 1 second, peak oxygen uptake, body mass index, dyspnea score, and smoking were assessed. Enrichment pathways and network analyses were implemented, using a list of cytokines showing differential expression between healthy controls and patients with COPD by Cytoscape and GeneGo Metacore™ software (Thomson-Reuters Corporation, New York, NY, USA). Concentrations of cutaneous T-cell attracting chemokine, eotaxin, hepatocyte growth factor, interleukin 6 (IL-6), IL-16, and stem cell factor are significantly higher in COPD patients compared with in control patients. Notably, this study identifies stem cell factor as a biomarker for COPD. Multiple regression analysis predicts that cutaneous T-cell-attracting chemokine, eotaxin, IL-6, and stem cell factor are inversely associated with forced expiratory volume in 1 second and peak oxygen uptake change, whereas smoking is related to eotaxin and hepatocyte growth factor changes. Enrichment pathways and network analyses reveal the potential involvement of specific inflammatory and immune process pathways in COPD. Identified network interaction and regulation of different cytokines would pave the way for deeper insight into mechanisms of the disease process.


Assuntos
Citocinas/sangue , Mediadores da Inflamação/sangue , Análise Serial de Proteínas , Doença Pulmonar Obstrutiva Crônica/sangue , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Volume Expiratório Forçado , Humanos , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Mapas de Interação de Proteínas , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/imunologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Fatores de Risco , Transdução de Sinais , Fumar/efeitos adversos , Fumar/imunologia , Espirometria , Capacidade Vital
6.
PLoS One ; 8(3): e58276, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23536792

RESUMO

BACKGROUND: Reptiles are phylogenically important group of organisms as mammals have evolved from them. Wall lizard testis exhibits clearly distinct morphology during various phases of a reproductive cycle making them an interesting model to study regulation of spermatogenesis. Studies on reptile spermatogenesis are negligible hence this study will prove to be an important resource. METHODOLOGY/PRINCIPAL FINDINGS: Histological analyses show complete regression of seminiferous tubules during regressed phase with retracted Sertoli cells and spermatognia. In the recrudescent phase, regressed testis regain cellular activity showing presence of normal Sertoli cells and developing germ cells. In the active phase, testis reaches up to its maximum size with enlarged seminiferous tubules and presence of sperm in seminiferous lumen. Total RNA extracted from whole testis of regressed, recrudescent and active phase of wall lizard was hybridized on Mouse Whole Genome 8×60 K format gene chip. Microarray data from regressed phase was deemed as control group. Microarray data were validated by assessing the expression of some selected genes using Quantitative Real-Time PCR. The genes prominently expressed in recrudescent and active phase testis are cytoskeleton organization GO 0005856, cell growth GO 0045927, GTpase regulator activity GO: 0030695, transcription GO: 0006352, apoptosis GO: 0006915 and many other biological processes. The genes showing higher expression in regressed phase belonged to functional categories such as negative regulation of macromolecule metabolic process GO: 0010605, negative regulation of gene expression GO: 0010629 and maintenance of stem cell niche GO: 0045165. CONCLUSION/SIGNIFICANCE: This is the first exploratory study profiling transcriptome of three drastically different conditions of any reptilian testis. The genes expressed in the testis during regressed, recrudescent and active phase of reproductive cycle are in concordance with the testis morphology during these phases. This study will pave the way for deeper insight into regulation and evolution of gene regulatory mechanisms in spermatogenesis.


Assuntos
Perfilação da Expressão Gênica , Lagartos/fisiologia , Espermatogênese/genética , Testículo/fisiologia , Animais , Cruzamento , Análise por Conglomerados , Biologia Computacional , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Masculino , Anotação de Sequência Molecular , Reprodutibilidade dos Testes , Reprodução/genética , Estações do Ano , Testículo/citologia
7.
Protein J ; 30(8): 575-80, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21989589

RESUMO

The watermelon (Citrullus lanatus) seeds are highly nutritive and contain large amount of proteins and many beneficial minerals such as magnesium, calcium, potassium, iron, phosphorous, zinc etc. In various parts of the world, C. lanatus seed extracts are used to cure cancer, cardiovascular diseases, hypertension, and blood pressure. C. lanatus seed extracts are also used as home remedy for edema and urinary tract problems. In this study, we isolated protein fraction of C. lanatus seeds using various protein separation methods. We successfully purified a low molecular weight vicilin-like glycoprotein using chromatographic methods followed by SDS-PAGE and MALDI-TOF/MS identification. This is the first report of purification of a vicilin like polypeptide from C. lanatus seeds. In next step, we extracted mRNA from immature seeds and reverse transcribed it using suitable forward and reverse primers for purified glycoprotein. The PCR product was analysed on 1% agarose gel and was subsequently sequenced by Dideoxy DNA sequencing method. An amino acid translation of the gene is in agreement with amino acid sequences of the identified peptides.


Assuntos
Citrullus/química , Glicoproteínas/química , Glicoproteínas/isolamento & purificação , Proteínas de Armazenamento de Sementes/química , Proteínas de Armazenamento de Sementes/isolamento & purificação , Sequência de Aminoácidos , Sequência de Bases , Citrullus/genética , Citrullus/metabolismo , Glicoproteínas/genética , Glicoproteínas/metabolismo , Dados de Sequência Molecular , Peso Molecular , Proteínas de Armazenamento de Sementes/genética , Proteínas de Armazenamento de Sementes/metabolismo , Sementes/química , Sementes/genética , Sementes/metabolismo
8.
Reprod Biol Endocrinol ; 9: 49, 2011 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-21496281

RESUMO

BACKGROUND: Research on antimicrobial cationic peptides (AMPs) has gained pace toward using their potential to replace conventional antibiotics. These peptides preferentially interact with negatively charged membrane lipids typically seen in bacteria and thereby lead to membrane perturbations and membrane dysfunction. However, one possible disadvantage of AMP drugs is their potential for toxicity, especially to those cells which display externalization of negatively charged moieties to the outer leaflet of the plasma membrane during the process of syncytialization. Human placental villous trophoblast is one such cell type. Indeed, intra-vaginal administration of an antimicrobial cationic peptide Ala8,13,18-magainin II amide (AMA) which is a synthetic analogue of magainin 2 derived from Xenopus frog has been observed to result in inhibition of pregnancy establishment in monkeys. However, only little is known about the cellular behavior of early placental cytotrophoblasts (CTB) in the presence of cationic antimicrobial peptides. It is believed that suitable cell culture approaches using AMA as a representative alpha-helical AMP may yield tangible knowledge in this regard. METHODS: Immunocytochemical (ICC) analyses using confocal microscopy (n = 6 for each treatment sub-group) and Western blot (WB) method (n = 5 for each treatment sub-group) of CTB differentiation based on synthesis of beta-hCG and hPL, and apoptosis based on apoptosis-associated cytokeratin 18 neo-epitope (CK18f) were performed for CTB isolated from human first trimester placental villi and grown in serum-free primary culture for 24 h, 48 h and 96 h on rat-tail collagen with and without AMA (1000 ng/ml). Moreover, secretion of beta-hCG and hPL into conditioned media from isolated CTB grown in vitro for 24 h, 48 h and 96 h (n = 6/each sub-group) with and without AMA was examined using enzyme immunoassays. Furthermore, TUNEL assay, and cell viability based on LDH leakage into medium (n = 6/each sub-group) were assessed to examine the phenomenon of cell death with time and administration of AMA. RESULTS: CTB in serum-free primary culture showed increased (P < 0.05) level of synthesis and secretion of beta-hCG and hPL with time, and higher (P < 0.05) level of cellular cytokeratin 18 neo-epitope and number of TUNEL-positive cells, and LDH activity in conditioned medium at 96 h of culture. Exposure of CTB to AMA resulted in lower (P < 0.05) level of synthesis and secretion of beta-hCG and hPL, as well as, an increase (P < 0.05) of cellular cytokeratin 18 neo-epitope and number of TUNEL-positive cells, and LDH activity in conditioned medium at 96 h as compared to the control treatment. CONCLUSIONS: Administration of AMA resulted in attenuation of differentiation, enhancement in apoptosis and loss of viability in early placental villi trophoblast cells in primary culture. Thus, it appears that administration of alpha-helical AMP may adversely affect the process of placentation and pregnancy outcome.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Trofoblastos/efeitos dos fármacos , Trofoblastos/metabolismo , Adulto , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Gonadotropina Coriônica Humana Subunidade beta/biossíntese , Feminino , Humanos , Queratina-18/biossíntese , L-Lactato Desidrogenase/metabolismo , Lactogênio Placentário , Gravidez , Primeiro Trimestre da Gravidez
9.
Biophys Chem ; 129(2-3): 126-36, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17601648

RESUMO

Atomic force microscopy (AFM) has been used to visualize the process of condensation of plasmid DNA by poly-L-ornithine on mica surface. AFM images reveal that the transition of negatively charged DNA to condensed nanoparticles on addition of increasing amounts of positively charged poly-L-ornithine (charge ratio (Z+/Z-) varied between 0.1 and 1) at a wide range of DNA concentrations (3-20 ng/microl) occurs through formation of several distinct morphologies. The nature of the complexes is strongly dependent on both the charge ratio and the DNA concentration. Initiation of condensation when the concentration of DNA is low (approximately 3-7 ng/microl) occurs possibly through formation of monomolecular complexes which are thick rod-like in shape. On the contrary, when condensation is carried out at DNA concentrations of 13-20 ng/microl, multimolecular structures are also formed even at low charge ratios. This difference in pathway seems to result in differences in the extent of condensation as well as size and aggregation of the nanoparticles formed at the high charge ratios. To the best of our knowledge, this is the first direct single molecule elucidation of the mechanism of DNA condensation by poly-L-ornithine. Cationic poly-aminoacids like poly-L-ornithine are known to be efficient in delivery of plasmid DNA containing therapeutic genes in a variety of mammalian cell lines by forming condensed "nanocarriers" with DNA. Single molecule insight into the mechanism by which such nanocarriers are packaged during the condensation process could be helpful in predicting efficacy of intracellular delivery and release of DNA from them and also provide important inputs for design of new gene delivery vectors.


Assuntos
DNA/química , Microscopia de Força Atômica , Nanocápsulas/química , Conformação de Ácido Nucleico , Peptídeos/química , Silicatos de Alumínio/química , Ensaio de Desvio de Mobilidade Eletroforética , Plasmídeos/química
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