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1.
Med Biol Eng Comput ; 62(5): 1491-1501, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38300437

RESUMO

Cancer is an invasive and malignant growth of cells and is known to be one of the most fatal diseases. Its early detection is essential for decreasing the mortality rate and increasing the probability of survival. This study presents an efficient machine learning approach based on the state vector machine (SVM) to diagnose and classify tumors into malignant or benign cancer using the online lymphographic data. Further, two types of neural network architectures are also implemented to evaluate the performance of the proposed SVM-based approach. The optimal structures of the classifiers are obtained by varying the architecture, topology, learning rate, and kernel function and recording the results' accuracy. The classifiers are trained with the preprocessed data examples after noise removal and tested on the unknown cases to diagnose each example as positive or negative. Further, the positive cases are classified into different stages including metastases, malign lymph, and fibrosis. The results are evaluated against the feed-forward and generalized regression neural networks. It is found that the proposed SVM-based approach significantly improves the early detection and classification accuracy in comparison to the experienced physicians and the other machine learning approaches. The proposed approach is robust and can perform sub-class divisions for multipurpose tasks. Experimental results demonstrate that the two-class SVM gives the best results and can effectively be used for the classification of cancer. It has outperformed all other classifiers with an average accuracy of 94.90%.


Assuntos
Neoplasias , Máquina de Vetores de Suporte , Algoritmos , Redes Neurais de Computação , Aprendizado de Máquina , Probabilidade , Neoplasias/diagnóstico
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 311: 123957, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38310741

RESUMO

The drug pharmacokinetics is affected upon binding with proteins, thus making drug-protein interactions crucial. This study investigated the interaction between enzalutamide and human major antiproteinase alpha-2-macroglobulin (α2M) by using multi spectroscopic and calorimetric techniques. The spectroscopic techniques such as circular dichroism (CD), intrinsic fluorescence, and UV-visible absorption were used to determine the mechanism of enzalutamide-α2M interaction. Studies on the quenching of fluorescence at three different temperatures showed that the enzalutamide-α2M complex is formed through static quenching mechanism. The change in microenvironment around tyrosine residues in protein was detected through synchronised fluorescence. The secondary structure of α2M was slightly altered by enzalutamide according to far UV-CD spectral analysis. Changes in position of amide I band in FTIR spectra further confirm the secondary structural alteration in α2M. According to thermodynamic characteristics such as fluorescence quenching and isothermal titration calorimetry (ITC), hydrogen bonds and hydrophobic interactions were involved in the interaction machanism. The ITC reiterated the exothermic and spontaneous nature of the interaction. The lower proteinase inhibitory activity of the α2M-enzalutamide conjugate as reflects the disruption of the native α2M structure upon interaction with enzalutamide.


Assuntos
Antineoplásicos , Benzamidas , Feniltioidantoína , alfa 2-Macroglobulinas Associadas à Gravidez , Humanos , Gravidez , Feminino , alfa 2-Macroglobulinas Associadas à Gravidez/química , Dicroísmo Circular , Nitrilas , Termodinâmica , Ligação Proteica , Simulação de Acoplamento Molecular , Espectrometria de Fluorescência , Calorimetria , Sítios de Ligação
3.
Med Oncol ; 41(2): 55, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38216843

RESUMO

Chronic Myeloid Leukemia (CML) is a myeloproliferative disorder distinguished by a specific genetic anomaly known as a reciprocal translocation between chromosomes 9 and 22. This translocation causes fusion between the BCR and ABL regions. Consequently, BCR::ABL oncoprotein is formed, which plays a significant role in driving CML progression. Imatinib, a tyrosine kinase inhibitor (TKI), became the first line of drugs against CML. However, with continuous treatment, patients developed resistance against it. Indeed, to address this challenge, microRNA-based therapy emerges as a promising approach. miRNAs are 20-25 nucleotides long and hold great significance in various cellular processes, including cell differentiation, proliferation, migration, and apoptosis. In several malignancies, it has been reported that miRNAs might help to promote or prevent tumourigenesis and abnormal expression because they could act as both oncogenes/tumor suppressors. Recently, because of their vital regulatory function in maintaining cell homeostasis, miRNAs might be used to control CML progression and in developing new therapies for TKI-resistant patients. They might also act as potential prognostic, diagnostic, and therapeutic biomarkers based on their expression profiles. Various annotation tools and microarray-based expression profiles can be used to predict dysregulated miRNAs and their target genes. The main purpose of this review is to provide brief insights into the role of dysregulated miRNAs in CML pathogenesis and to emphasize their clinical relevance, such as their significant potential as therapeutics against CML. Utilizing these miRNAs as a therapeutic approach by inhibition or amplification of their activity could unlock new doors for the therapy of CML.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , MicroRNAs , Humanos , MicroRNAs/genética , Proteínas de Fusão bcr-abl , Resistencia a Medicamentos Antineoplásicos/genética , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Apoptose
4.
Med Oncol ; 40(8): 237, 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37439908

RESUMO

Chronic myeloid leukemia (CML) is a type of blood cancer that is known to affect hematopoietic stem cells. The presence of the Philadelphia chromosome (Ph+) is the major characteristic of CML. A protein expressed by the Philadelphia chromosome shows elevated tyrosine kinase activity and is considered a tumorigenic factor. The first line of therapy that had been established for CML was "imatinib," a potent tyrosine kinase inhibitor. Various other second- and third-generation TKIs are taken into account in cases of imatinib failure/resistance. With the subsequent rise in the development of tyrosine kinase inhibitors, optimization in the treatment of CML and amplified total survival were observed throughout TKI dosage. As the disease progresses, additional chromosomal abnormalities (ACAs) have been reported, but their prognostic effect and impact on the response to treatment are still unknown. However, some substantial understandings have been achieved into the disease transformation mechanisms, including the role of somatic mutations, ACAs, and several different genomic mutations that occur during diagnosis or have evolved during treatment. The acquisition of ACAs impedes CML treatment. Due to additional chromosomal lesions, there are greater chances of future disease progression at the time of CML diagnosis beyond the Ph+ translocation. The synchronous appearance of two or more ACAs leads to lower survival and is classified as a poor prognostic group. The key objective of this review is to provide detailed insights into TKIs and their role in controlling Ph+ and ACAs, along with their response, treatment, overall persistence, and survival rate.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Humanos , Cromossomo Filadélfia , Mesilato de Imatinib/farmacologia , Mesilato de Imatinib/uso terapêutico , Aberrações Cromossômicas , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico
5.
J Biomed Mater Res A ; 111(9): 1423-1440, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37021718

RESUMO

In tissue engineering, cells are grown often on scaffolds and subjected to chemical/mechanical stimuli. Most such cultures still use fetal bovine serum (FBS) despite its known disadvantages including ethical concerns, safety issues, and variability in composition, which greatly influences the experimental outcomes. To overcome the disadvantages of using FBS, chemically defined serum substitute medium needs to be developed. Development of such medium depends on cell type and application-which makes it impossible to define one universal serum substitute medium for all cells in any application. Here, we developed a serum substitute medium for bone tissue engineering (BTE) in a step-by-step process. Essential components were added to the medium while human bone marrow mesenchymal stromal cells (hBMSCs, osteoblast progenitor cells) were cultured in two-dimensional and three-dimensional substrates. In a 3-week culture, the developed serum substitute medium worked equally well as FBS containing medium in term of cell attachment to the substrate, cell survival, osteoblast differentiation, and deposition of extracellular matrix. In the next step, the use of serum substitute medium was evaluated when culturing cells under mechanical loading in the form of shear stress. The outcomes showed that the application of shear stress is essential to improve extracellular matrix formation while using serum substitute medium. The developed serum substitute medium could pave the way in replacing FBS for BTE studies eliminating the use of controversial FBS and providing a better-defined chemical environment for BTE studies.


Assuntos
Células-Tronco Mesenquimais , Engenharia Tecidual , Humanos , Engenharia Tecidual/métodos , Proliferação de Células , Soro/química , Soro/metabolismo , Osso e Ossos , Diferenciação Celular , Células Cultivadas
6.
J Biol Phys ; 49(1): 29-48, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36662317

RESUMO

Myricetin (MYR) is a bioactive secondary metabolite found in plants that is recognized for its nutraceutical value and is an essential constituent of various foods and beverages. It is reported to exhibit a plethora of activities, including antioxidant, antimicrobial, antidiabetic, anticancer, and anti-inflammatory. Alpha-2-macroglobulin (α2M) is a major plasma anti-proteinase that can inhibit proteinases of both human and non-human origin, regardless of their specificity and catalytic mechanism. Here, we explored the interaction of MYR-α2M using various biochemical and biophysical techniques. It was found that the interaction of MYR brings subtle change in its anti-proteolytic potential and thereby alters its structure and function, as can be seen from absorbance and fluorescence spectroscopy. UV spectroscopy of α2M in presence of MYR indicated the occurrence of hyperchromism, suggesting complex formation. Fluorescence spectroscopy reveals that MYR reduces the fluorescence intensity of native α2M with a shift in the wavelength maxima. At 318.15 K, MYR binds to α2M with a binding constant of 2.4 × 103 M-1, which indicates significant binding. The ΔG value was found to be - 7.56 kcal mol-1 at 298.15 K, suggesting the interaction to be spontaneous and thermodynamically favorable. The secondary structure of α2M does not involve any major change as was confirmed by CD analysis. The molecular docking indicates that Asp-146, Ser-172, Glu-174, and Tyr-180 were the key residues involved in α2M-MYR complex formation. This study contributes to our understanding of the function and mechanism of protein and flavonoid binding by providing a molecular basis of the interaction between MYR and α2M.


Assuntos
alfa 2-Macroglobulinas Associadas à Gravidez , Humanos , Gravidez , Feminino , Simulação de Acoplamento Molecular , alfa 2-Macroglobulinas Associadas à Gravidez/química , alfa 2-Macroglobulinas Associadas à Gravidez/metabolismo , Análise Espectral , Flavonoides
7.
Radiographics ; 42(6): 1776-1794, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36190851

RESUMO

The expansion and dissemination of interventional cryoneurolysis in recent years has been fueled by the integration of advanced imaging guidance, the evolution of our understanding of neuropathologic processes after exposure of nerves to cold, and opportunities for its use beyond pain management. The clinical translation of cryoneurolysis through interventional radiology requires consideration of many factors, including (a) the supply and composition of target nerves, (b) the value of diagnostic injection with imaging guidance for confirmation, (c) the integration of advanced imaging guidance that allows safe ablation, (d) the difference between neoplastic and nonneoplastic causes of pain, (e) the phenomenon of percutaneously induced neuroregeneration, (f) the potential to manage conditions other than pain, (g) the consideration of protocols, (h) the limitations of current technology, and (i) the potential complications and adverse effects. Cryoneurolysis has societal and legislative endorsement as an effective nonopioid option for pain palliation. The Centers for Medicare and Medicaid Services (CMS) approved three new category III Current Procedural Terminology (CPT) codes specifically for the cryoablation of nerves with advanced imaging guidance. Interventional radiologists who are aware of nerve-directed strategies see eligible patients in their daily practice and have opportunities to bundle procedures (eg, celiac plexus block at the time of a biliary drain for pancreatic cancer with low bile duct obstruction), offering an avenue to serve the patient, reduce opioid dependence, allow faster discharge, and establish name recognition of interventional radiologists. Also, the ability to use CT to target deep structures accurately and swiftly, often with only local anesthesia, compared with the usual monitored anesthesia care in a surgical setting, may provide another avenue to build a cryoneurolysis practice. ©RSNA, 2022.


Assuntos
Criocirurgia , Medicare , Idoso , Criocirurgia/métodos , Humanos , Dor , Manejo da Dor/métodos , Radiologia Intervencionista , Estados Unidos
8.
Curr Osteoporos Rep ; 19(1): 88-100, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33447910

RESUMO

PURPOSE OF REVIEW: One aim in bone tissue engineering is to develop human cell-based, 3D in vitro bone models to study bone physiology and pathology. Due to the heterogeneity of cells among patients, patient's own cells are needed to be obtained, ideally, from one single cell source. This review attempts to identify the appropriate cell sources for development of such models. RECENT FINDINGS: Bone marrow and peripheral blood are considered as suitable sources for extraction of osteoblast/osteocyte and osteoclast progenitor cells. Recent studies on these cell sources have shown no significant differences between isolated progenitor cells. However, various parameters such as medium composition affect the cell's proliferation and differentiation potential which could make the peripheral blood-derived stem cells superior to the ones from bone marrow. Peripheral blood can be considered a suitable source for osteoblast/osteocyte and osteoclast progenitor cells, being less invasive for the patient. However, more investigations are needed focusing on extraction and differentiation of both cell types from the same donor sample of peripheral blood.


Assuntos
Modelos Biológicos , Osteogênese/fisiologia , Engenharia Tecidual/métodos , Células da Medula Óssea/metabolismo , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Humanos , Técnicas In Vitro , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteócitos/metabolismo , Células-Tronco/metabolismo
9.
Obstet Gynecol ; 135(5): 1091-1094, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32282604

RESUMO

Recent studies have implicated long-term pentosan polysulfate use with vision loss from a newly described macular condition. Affected patients report difficulty with reading and adjusting to dim lighting, and they occasionally develop severe visual disability. Macular changes resemble those seen in age-related macular degeneration, potentially leading to misdiagnosis. The objectives of this Current Commentary are to summarize studies evaluating the association between pentosan polysulfate use and macular disease, to educate pentosan polysulfate prescribers about the clinical manifestations of this condition, and to provide recommendations for screening at-risk patients.


Assuntos
Cistite Intersticial/tratamento farmacológico , Degeneração Macular/induzido quimicamente , Poliéster Sulfúrico de Pentosana/efeitos adversos , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade
10.
Int Urogynecol J ; 28(8): 1257-1260, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28091712

RESUMO

INTRODUCTION AND HYPOTHESIS: Female urethral reconstruction via the traditional routes can be limiting for various reasons. Current literature on the use of acellular biologic grafts derived from viscera for female urethral reconstruction is limited. We present two cases of women with complete loss of their posterior urethra presenting for urethral reconstruction. METHODS: Two cases of urethral reconstruction using acellular porcine urinary bladder matrix (UBM), along with labial fat pad transposition and biologic pubovaginal sling are presented. RESULTS: In both cases the UBM graft showed successful conversion to what appeared to be normal urethral mucosa. One woman showed significant improvement in continence and the other showed complete continence. CONCLUSIONS: Female urethral reconstruction using acellular porcine UBM is a viable option for patients who have lost a significant portion of their urethra. Both cases demonstrated transition of the graft into the posterior wall of the urethra with significant improvement in continence. Further studies are needed to confirm that acellular porcine UBM can transform to urethral mucosa in women requiring urethral reconstruction.


Assuntos
Matriz Extracelular/transplante , Procedimentos de Cirurgia Plástica/métodos , Engenharia Tecidual/métodos , Uretra/cirurgia , Bexiga Urinária/transplante , Adulto , Idoso , Animais , Feminino , Humanos , Slings Suburetrais , Suínos , Resultado do Tratamento
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