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1.
Behav Neurol ; 2024: 4678554, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38882177

RESUMO

The most common and aggressive tumor is brain malignancy, which has a short life span in the fourth grade of the disease. As a result, the medical plan may be a crucial step toward improving the well-being of a patient. Both diagnosis and therapy are part of the medical plan. Brain tumors are commonly imaged with magnetic resonance imaging (MRI), positron emission tomography (PET), and computed tomography (CT). In this paper, multimodal fused imaging with classification and segmentation for brain tumors was proposed using the deep learning method. The MRI and CT brain tumor images of the same slices (308 slices of meningioma and sarcoma) are combined using three different types of pixel-level fusion methods. The presence/absence of a tumor is classified using the proposed Tumnet technique, and the tumor area is found accordingly. In the other case, Tumnet is also applied for single-modal MRI/CT (561 image slices) for classification. The proposed Tumnet was modeled with 5 convolutional layers, 3 pooling layers with ReLU activation function, and 3 fully connected layers. The first-order statistical fusion metrics for an average method of MRI-CT images are obtained as SSIM tissue at 83%, SSIM bone at 84%, accuracy at 90%, sensitivity at 96%, and specificity at 95%, and the second-order statistical fusion metrics are obtained as the standard deviation of fused images at 79% and entropy at 0.99. The entropy value confirms the presence of additional features in the fused image. The proposed Tumnet yields a sensitivity of 96%, an accuracy of 98%, a specificity of 99%, normalized values of the mean of 0.75, a standard deviation of 0.4, a variance of 0.16, and an entropy of 0.90.


Assuntos
Neoplasias Encefálicas , Aprendizado Profundo , Imageamento por Ressonância Magnética , Meningioma , Imagem Multimodal , Tomografia Computadorizada por Raios X , Humanos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/classificação , Imageamento por Ressonância Magnética/métodos , Meningioma/diagnóstico por imagem , Meningioma/patologia , Meningioma/classificação , Imagem Multimodal/métodos , Tomografia Computadorizada por Raios X/métodos , Sarcoma/diagnóstico por imagem , Sarcoma/patologia , Sarcoma/classificação , Processamento de Imagem Assistida por Computador/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Redes Neurais de Computação , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/classificação
2.
Int J Obstet Anesth ; 55: 103899, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37329691

RESUMO

BACKGROUND: Spinal anaesthesia, the most common form of anaesthesia for caesarean section, leads to sympathetic blockade and profound maternal hypotension resulting in adverse maternal and neonatal outcomes. Hypotension, nausea and vomiting remain common but until the publication of the National Institute of Health and Care Excellence (NICE) 2021 guidance, no national guideline existed on how best to manage maternal hypotension following spinal anaesthesia for caesarean section. A 2017 international consensus statement recommended prophylactic vasopressor administration to maintain a systolic blood pressure of >90% of an accurate pre-spinal value, and to avoid a drop to <80% of this value. This survey aimed to assess regional adherence to these recommendations, the presence of local guidelines for management of hypotension during caesarean section under spinal anaesthesia, and the individual clinician's treatment thresholds for maternal hypotension and tachycardia. METHODS: The West Midlands Trainee-led Research in Anaesthesia and Intensive Care Network co-ordinated surveys of obstetric anaesthetic departments and consultant obstetric anaesthetists across 11 National Health Service Trusts in the Midlands, England. RESULTS: One-hundred-and-two consultant obstetric anaesthetists returned the survey and 73% of sites had a policy for vasopressor use; 91% used phenylephrine as the first-line drug but a wide range of recommended delivery methods was noted and target blood pressure was only listed in 50% of policies. Significant variation existed in both vasopressor delivery methods and target blood pressures. CONCLUSIONS: Although NICE has since recommended prophylactic phenylephrine infusion and a target blood pressure, the previous international consensus statement was not adhered to routinely.


Assuntos
Anestesia Obstétrica , Raquianestesia , Cesárea , Hipotensão , Vasoconstritores , Humanos , Feminino , Gravidez , Adulto , Hipotensão/etiologia , Raquianestesia/efeitos adversos , Anestesia Obstétrica/efeitos adversos , Reino Unido , Inquéritos e Questionários , Vasoconstritores/administração & dosagem , Vasoconstritores/efeitos adversos
3.
Healthcare (Basel) ; 10(7)2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35885745

RESUMO

MRI is an influential diagnostic imaging technology specifically worn to detect pathological changes in tissues with organs early. It is also a non-invasive imaging method. Medical image segmentation is a complex and challenging process due to the intrinsic nature of images. The most consequential imaging analytical approach is MRI, which has been in use to detect abnormalities in tissues and human organs. The portrait was actualized for CAD (computer-assisted diagnosis) utilizing image processing techniques with deep learning, initially to perceive a brain tumor in a person with early signs of brain tumor. Using AHCN-LNQ (adaptive histogram contrast normalization with learning-based neural quantization), the first image is preprocessed. When compared to extant techniques, the simulation outcome shows that this proposed method achieves an accuracy of 93%, precision of 92%, and 94% of specificity.

4.
Chemosphere ; 295: 133848, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35122815

RESUMO

SnO2 with different Co2+ doping concentrations and Co (0.075 M): SnO2 loaded corn cob activated carbon (Co: SnO2/CCAC) were prepared, and are labelled as CS1, CS2, CS3 and CS2/CCAC, respectively. The CS2/CCAC showed that the particle size (18.76 nm) and band gap (3.50 eV) are reduced with Co2+ doping and CCAC loading. Moreover, CS2/CCAC indicate that the decreased PL intensity and its lower value (2.156 kΩ) of impedance from EIS results which indicates the increased separation of the photogenerated e-/h+ pairs. Thus, the result showed that CS2/CCAC maximum degradation efficiency of MB (95.38%) and the photocatalytic mechanism is also discussed.


Assuntos
Carvão Vegetal , Azul de Metileno , Catálise , Luz Solar , Zea mays
5.
Cryo Letters ; 43(3): 158-166, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36626140

RESUMO

BACKGROUND: Dissolved oxygen (DO) in semen dilutor may lead to the production of reactive oxygen species (ROS) and buffalo sperm may become more prone to deleterious effects of ROS due to the presence of high amounts of polyunsaturated fatty acids (PUFAs) in their membranes. OBJECTIVE: To study the correlation between dissolved oxygen level, antioxidants and oxidants in semen diluted with partially deoxygenated extender at various stages of cryopreservation. MATERIALS AND METHODS: Each semen sample was split into two aliquots viz., Aliquot I [diluted with Extender I (control: without deoxygenation)] and Aliquot II [diluted with Extender II: partially deoxygenated by liquid nitrogen (LN) flushing], which were diluted, filled in straws, cryopreserved and evaluated post-thaw. RESULTS: The DO levels (P < 0.05) decreased significantly after LN flushing of the extender and they increased significantly (P < 0.05) in post-thaw semen. The progressive motility, viability, hypo-osmotic swelling response, acrosomal integrity, glutathione peroxidase (GPx), total antioxidant capacity (TAC) and superoxide dismutase (SOD) decreased significantly (P < 0.05) in both control and treated semen after thawing. SOD and TAC were positively correlated in semen treated with normal extender at the pre-freeze stage; however, in semen treated with partially deoxygenated extender, no correlation was found between SOD and TAC at the pre-freeze stage. ROS and total TAC were negatively correlated in semen treated with partially deoxygenated extender at the pre-freeze stage; however, no correlation was found between ROS and TAC in control semen. CONCLUSION: The partial deoxygenation of extender affects the correlation between sperm quality parameters, antioxidants, and oxidants during different stages of semen cryopreservation. doi.org/10.54680/fr22310110712.


Assuntos
Preservação do Sêmen , Sêmen , Animais , Masculino , Antioxidantes/farmacologia , Oxigênio/farmacologia , Criopreservação , Análise do Sêmen , Espécies Reativas de Oxigênio , Oxidantes/farmacologia , Motilidade dos Espermatozoides , Crioprotetores/farmacologia , Preservação do Sêmen/veterinária , Espermatozoides , Búfalos/fisiologia , Superóxido Dismutase/farmacologia
6.
Cell Mol Biol Lett ; 20(2): 294-309, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26204409

RESUMO

Lamin A is an intermediate filament protein which is cleaved by the enzyme, FACE 1 at VTRSY↓L. The cleavage is the final step in the production of the mature lamin A protein. The mature lamin A protein localizes in the inner membrane of the nucleus. The mutation in the lamin A gene causes many diseases, including accelerated aging. It is known that the protein is not expressed in neuronal cells of the brain. Many splicing variants of the lamin A gene have been reported. In this study, the amino acid sequence VTRSY (a penta-peptide repeat) was found in three different sites of the C-terminal end of the lamin A protein, the protein expressed in cells of ear cartilage tissues is shorter than the protein expressed in cells of the skin tissues. Using two lamin A antibodies, it was found that the amino acid sequence between penta-peptide 2 and 3 is missing in lamin A protein that was expressed in the cells of mouse ear cartilage tissue, besides the RT-PCR data confirmed that the corresponding coding sequence between the penta repeat 2 and 3 is intact. Cleavage may occur at the penta-peptide (VTRSY) at site 3 in the lamin A tail of mouse ear cartilage.


Assuntos
Cartilagem da Orelha/metabolismo , Lamina Tipo A/metabolismo , Processamento de Proteína Pós-Traducional , Sequência de Aminoácidos , Animais , Expressão Gênica , Lamina Tipo A/genética , Camundongos , Dados de Sequência Molecular , Pele/metabolismo
7.
Cell Biol Int ; 39(9): 1036-43, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25858151

RESUMO

Lamin A is an intermediate filament protein found in most of the differentiated vertebrate cells but absent in stem cells. It shapes the skeletal frame structure beneath the inner nuclear membrane of the cell nucleus. As there are few studies of the expression of lamin A in invertebrates, in the present work, we have analyzed the sequence, immunochemical conservation and expression pattern of lamin A protein in the earthworm Eudrilus eugeniae, a model organism for tissue regeneration. The expression of lamin A has been confirmed in E. eugeniae by immunoblot. Its localization in the nuclear membrane has been observed by immunohistochemistry using two different rabbit anti-sera raised against human lamin A peptides, which are located at the C-terminus of the lamin A protein. These two antibodies detected 70 kDa lamin A protein in mice and a single 65 kDa protein in the earthworm. The Oct-4 positive undifferentiated blastemal tissues of regenerating earthworm do not express lamin A, while the Oct-4 negative differentiated cells express lamin A. This pattern was also confirmed in the earthworm prostate gland. The present study is the first evidence for the immunochemical identification of lamin A and Oct-4 in the earthworm. Along with the partial sequence obtained from the earthworm genome, the present results suggest that lamin A protein and its expression pattern is conserved from the earthworm to humans.


Assuntos
Lamina Tipo A/biossíntese , Lamina Tipo A/genética , Oligoquetos/genética , Sequência de Aminoácidos , Animais , Diferenciação Celular/fisiologia , Sequência Conservada , Expressão Gênica , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Proteínas de Filamentos Intermediários/biossíntese , Proteínas de Filamentos Intermediários/genética , Dados de Sequência Molecular , Membrana Nuclear/metabolismo , Fator 3 de Transcrição de Octâmero/biossíntese , Fator 3 de Transcrição de Octâmero/genética , Oligoquetos/metabolismo , Regeneração/genética , Regeneração/fisiologia , Alinhamento de Sequência , Análise de Sequência de Proteína
8.
Cell Death Differ ; 20(4): 558-66, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23238568

RESUMO

The current paradigm states that the Akt signaling pathway phosphorylates the human oncoprotein mouse double minute 2 (MDM2), leading to its nuclear translocation and degradation of the tumor suppressor p53. Here we report a novel Akt signaling pathway elicited by MDM2. Upregulation of endogenous MDM2 promotes, whereas its downregulation diminishes, Akt phosphorylation irrespective of p53 status. MDM2 requires phosphatidylinositol (PI)3-kinase activity for enhancing Akt phosphorylation and upregulates this activity by repressing transcription of the regulatory subunit p85 of PI3-kinase. MDM2 interacts with the repressor element-1 silencing transcription factor (REST), a tumor suppressor that functions by downregulating PI3-kinase activity and Akt phosphorylation, prevents localization of REST on the p85 promoter and represses p85 expression. The deletion mutant of MDM2 capable of upregulating Akt phosphorylation represses p85 expression and interferes with localization of REST on the p85 promoter, whereas the deletion mutant of MDM2 that does not increase Akt phosphorylation cannot perform these functions. Silencing of REST abrogates the ability of MDM2 to upregulate Akt phosphorylation and downregulate p85 expression, implicating the ability of MDM2 to interact with REST in its ability to inhibit p85 expression and activate Akt phosphorylation. Inhibition of MDM2-mediated Akt phosphorylation with an Akt-phosphorylation-specific inhibitor abrogates its ability to improve cell survival. Consistently, the Akt phosphorylation function of MDM2 was required for its ability to improve cell survival after treatment with a chemotherapeutic drug. Our report not only unravels a novel signaling pathway that contributes to cell survival but also implicates a p53-independent transcription regulatory function of MDM2 in Akt signaling.


Assuntos
Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteínas Repressoras/metabolismo , Animais , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Classe Ia de Fosfatidilinositol 3-Quinase/genética , Classe Ia de Fosfatidilinositol 3-Quinase/metabolismo , Etoposídeo/farmacologia , Humanos , Camundongos , Camundongos Transgênicos , Fosfatidilinositol 3-Quinase/genética , Fosfatidilinositol 3-Quinase/metabolismo , Fosforilação , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/genética , Interferência de RNA , RNA Interferente Pequeno , Transdução de Sinais , Proteína Supressora de Tumor p53/deficiência , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
9.
Stem Cells Dev ; 21(11): 2071-83, 2012 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-22150027

RESUMO

The earthworm, Eudrilus eugeniae, has a prodigious ability to regenerate lost segments. The skin of the worm has an outermost epidermal layer followed by a thick circular muscle layer and an innermost thin longitudinal cell layer. During the process of regeneration, the circular muscle layer decreased in thickness, and longitudinal cell layer increased. The histological analysis of the regenerated worm shows that the longitudinal cell layer forms the regeneration blastema. BrdU-labeling retention assay confirmed that the circular muscle and longitudinal cell layers have BrdU-positive cells, which migrate from the adjacent segments to the regeneration blastema. In addition, it was noted that the cells of the earthworm, E. eugeniae, have the property of autofluorescence. Autofluorescence was found in the cytoplasm, but not in the nucleus. It has been also found that the major source for autofluorescence is riboflavin. Further, it was also demonstrated that supplementation with riboflavin increases the rate of regeneration, while regeneration was hampered by reduced levels of riboflavin. The importance of riboflavin in regeneration was also confirmed by rescue assay. In addition, it was also identified that BrdU-positive cells are highly fluorescent compared to the surrounding cells.


Assuntos
Bromodesoxiuridina/metabolismo , Oligoquetos/metabolismo , Regeneração , Riboflavina/metabolismo , Animais , Movimento Celular , Núcleo Celular/metabolismo , Cromatografia em Camada Fina , Citoplasma/metabolismo , Células Epidérmicas , Epiderme/metabolismo , Fluorescência , Imuno-Histoquímica , Músculos/citologia , Músculos/metabolismo , Músculos/fisiologia , Oligoquetos/citologia , Oligoquetos/efeitos dos fármacos , Oligoquetos/fisiologia , Riboflavina/farmacologia , Especificidade da Espécie
10.
J Biol Chem ; 273(13): 7657-67, 1998 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-9516471

RESUMO

Granulocyte-macrophage colony-stimulating factor (GM-CSF) activity is mediated by a cellular receptor (GM-CSFR) that is comprised of an alpha-chain (GM-CSFRalpha), which specifically binds GM-CSF, and a beta-chain (betac), shared with the interleukin-3 and interleukin-5 receptors. GM-CSFRalpha exists in both a transmembrane (tmGM-CSFRalpha) and a soluble form (sGM-CSFRalpha). We designed an sGM-CSFRalpha-Fc fusion protein to study GM-CSF interactions with the GM-CSFRalpha. The construct was prepared by fusing the coding region of the sGM-CSFRalpha with the CH2-CH3 regions of murine IgG2a. Purified sGM-CSFRalpha-Fc ran as a monomer of 60 kDa on reducing SDS-polyacrylamide gel electrophoresis but formed a trimer of 160-200 kDa under nonreducing conditions. The sGM-CSFRalpha-Fc bound specifically to GM-CSF as demonstrated by standard and competitive immunoassays, as well as by radioligand assay with 125I-GM-CSF. The sGM-CSFRalpha-Fc also inhibited GM-CSF-dependent cell growth and therein is a functional antagonist. Kinetics of sGM-CSFRalpha-Fc binding to GM-CSF were evaluated using an IAsys biosensor (Affinity Sensors, Paramus, NJ) with two assay systems. In the first, the sGM-CSFRalpha-Fc was bound to immobilized staphylococcal protein A on the biosensor surface, and binding kinetics of GM-CSF in solution were determined. This revealed a rapid koff of 2.43 x 10(-2)/s. A second set of experiments was performed with GM-CSF immobilized to the sensor surface and the sGM-CSFRalpha-Fc in solution. The dissociation rate constant (koff) for the sGM-CSFRalpha-Fc trimer from GM-CSF was 1.57 x 10(-3)/s, attributable to the higher avidity of binding in this assay. These data indicate rapid dissociation of GM-CSF from the sGM-CSFRalpha-Fc and suggest that in vivo, sGM-CSFRalpha may need to be present in the local environment of a responsive cell to exert its antagonist activity.


Assuntos
Fragmentos Fc das Imunoglobulinas/metabolismo , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Animais , Técnicas Biossensoriais , Linhagem Celular , Clonagem Molecular , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Fragmentos Fc das Imunoglobulinas/genética , Cinética , Camundongos , Ligação Proteica , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Solubilidade
11.
Phys Rev Lett ; 76(25): 4753-4756, 1996 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-10061372
12.
Phys Rev Lett ; 76(2): 267-270, 1996 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-10061058
14.
Phys Rev B Condens Matter ; 49(11): 7709-7715, 1994 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-10009517
15.
J Chem Ecol ; 19(8): 1691-701, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24249234

RESUMO

Allelochemicals fromGliricidia sepium were extracted, identified, and quantified using HPLC. Fifteen toxic compounds, namely gallic acid, protocatechuic acid,p-hydroxybenzoic acid, gentisic acid,Β-resorcyclic acid, vanillic acid, syringic acid,p-coumaric acid,m-coumaric acid,o-coumaric acid, ferulic acid, sinapinic acid (trans andcis forms), coumarin, and myricetin were identified and quantified. These compounds from the plant extracts were tested on the seeds of the crop plant,Sorghum vulgare. Rate of germination of the seeds and root elongation were found to be inhibited by the various compounds of the extract. Different quantities ofGliricidia leaf mulch, viz., 400, 800, and 1200 g/m(2) applied to theSorghum grown fields, were found to effectively control weeds. Mulching improved the total yield ofSorghum. Leaf manuring and mulching showed better crop yield when applied up to 800 g ofGliricidia leaf/m(2). Crop yield was better in mulch-applied fields when compared to the manure-applied ones.

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