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1.
Microb Pathog ; 189: 106572, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38354987

RESUMO

The JCV (John Cunningham Virus) is known to cause progressive multifocal leukoencephalopathy, a condition that results in the formation of tumors. Symptoms of this condition such as sensory defects, cognitive dysfunction, muscle weakness, homonosapobia, difficulties with coordination, and aphasia. To date, there is no specific and effective treatment to completely cure or prevent John Cunningham polyomavirus infections. Since the best way to control the disease is vaccination. In this study, the immunoinformatic tools were used to predict the high immunogenic and non-allergenic B cells, helper T cells (HTL), and cytotoxic T cells (CTL) epitopes from capsid, major capsid, and T antigen proteins of JC virus to design the highly efficient subunit vaccines. The specific immunogenic linkers were used to link together the predicted epitopes and subjected to 3D modeling by using the Robetta server. MD simulation was used to confirm that the newly constructed vaccines are stable and properly fold. Additionally, the molecular docking approach revealed that the vaccines have a strong binding affinity with human TLR-7. The codon adaptation index (CAI) and GC content values verified that the constructed vaccines would be highly expressed in E. coli pET28a (+) plasmid. The immune simulation analysis indicated that the human immune system would have a strong response to the vaccines, with a high titer of IgM and IgG antibodies being produced. In conclusion, this study will provide a pre-clinical concept to construct an effective, highly antigenic, non-allergenic, and thermostable vaccine to combat the infection of the John Cunningham virus.


Assuntos
Vírus JC , Vacinas , Humanos , Epitopos/genética , Simulação de Acoplamento Molecular , Escherichia coli , Vacinologia , Vacinas de Subunidades Antigênicas/genética , Epitopos de Linfócito T/genética , Biologia Computacional , Epitopos de Linfócito B , Simulação de Dinâmica Molecular
2.
Biologicals ; 86: 101770, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38749079

RESUMO

Monkeypox is a type of DNA-enveloped virus that belongs to the orthopoxvirus family, closely related to the smallpox virus. It can cause an infectious disease in humans known as monkeypox disease. Although there are multiple drugs and vaccines designed to combat orthopoxvirus infections, with a primary focus on smallpox, the recent spread of the monkeypox virus to over 50 countries have ignited a mounting global concern. This unchecked viral proliferation has raised apprehensions about the potential for a pandemic corresponding to the catastrophic impact of COVID-19. This investigation explored the structural proteins of monkeypox virus as potential candidates for designing a novel hybrid multi-epitope vaccine. The epitopes obtained from the selected proteins were screened to ensure their non-allergenicity, non-toxicity, and antigenicity to trigger T and B-cell responses. The interaction of the vaccine with toll-like receptor-3 (TLR-3) and major histocompatibility complexes (MHCs) was assessed using Cluspro 2.0. To establish the reliability of the docked complexes, a comprehensive evaluation was conducted using Immune and MD Simulations and Normal Mode Analysis. However, to validate the computational results of this study, additional in-vitro and in-vivo research is essential.


Assuntos
Monkeypox virus , Humanos , Monkeypox virus/imunologia , Simulação de Acoplamento Molecular , Pandemias/prevenção & controle , Imunogenicidade da Vacina , COVID-19/prevenção & controle , COVID-19/imunologia , Mpox/prevenção & controle , Mpox/imunologia , Epitopos/imunologia , Preparação para Pandemia
3.
Respir Res ; 24(1): 59, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36810085

RESUMO

OBJECTIVES: To investigate whether COVID-19 patients with pulmonary embolism had higher mortality and assess the utility of D-dimer in predicting acute pulmonary embolism. PATIENTS AND METHODS: Using the National Collaborative COVID-19 retrospective cohort, a cohort of hospitalized COVID-19 patients was studied to compare 90-day mortality and intubation outcomes in patients with and without pulmonary embolism in a multivariable cox regression analysis. The secondary measured outcomes in 1:4 propensity score-matched analysis included length of stay, chest pain incidence, heart rate, history of pulmonary embolism or DVT, and admission laboratory parameters. RESULTS: Among 31,500 hospitalized COVID-19 patients, 1117 (3.5%) patients were diagnosed with acute pulmonary embolism. Patients with acute pulmonary embolism were noted to have higher mortality (23.6% vs.12.8%; adjusted Hazard Ratio (aHR) = 1.36, 95% CI [1.20-1.55]), and intubation rates (17.6% vs. 9.3%, aHR = 1.38[1.18-1.61]). Pulmonary embolism patients had higher admission D-dimer FEU (Odds Ratio(OR) = 1.13; 95%CI [1.1-1.15]). As the D-dimer value increased, the specificity, positive predictive value, and accuracy of the test increased; however, sensitivity decreased (AUC 0.70). At cut-off D-dimer FEU 1.8 mcg/ml, the test had clinical utility (accuracy 70%) in predicting pulmonary embolism. Patients with acute pulmonary embolism had a higher incidence of chest pain and history of pulmonary embolism or deep vein thrombosis. CONCLUSIONS: Acute pulmonary embolism is associated with worse mortality and morbidity outcomes in COVID-19. We present D-dimer as a predictive risk tool in the form of a clinical calculator for the diagnosis of acute pulmonary embolism in COVID-19.


Assuntos
COVID-19 , Embolia Pulmonar , Humanos , Estudos Retrospectivos , Embolia Pulmonar/diagnóstico , Valor Preditivo dos Testes , Dor no Peito
4.
Anal Biochem ; 676: 115247, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37437648

RESUMO

Pseudouridine (ψ) is reported to occur frequently in all types of RNA. This uridine modification has been shown to be essential for processes such as RNA stability and stress response. Also, it is linked to a few human diseases, such as prostate cancer, anemia, etc. A few laboratory techniques, such as Pseudo-seq and N3-CMC-enriched Pseudouridine sequencing (CeU-Seq) are used for detecting ψ sites. However, these are laborious and drawn-out methods. The convenience of sequencing data has enabled the development of computationally intelligent models for improving ψ site identification methods. The proposed work provides a prediction model for the identification of ψ sites through popular ensemble methods such as stacking, bagging, and boosting. Features were obtained through a novel feature extraction mechanism with the assimilation of statistical moments, which were used to train ensemble models. The cross-validation test and independent set test were used to evaluate the precision of the trained models. The proposed model outperformed the preexisting predictors and revealed 87% accuracy, 0.90 specificity, 0.85 sensitivity, and a 0.75 Matthews correlation coefficient. A web server has been built and is available publicly for the researchers at https://taseersuleman-y-test-pseu-pred-c2wmtj.streamlit.app/.


Assuntos
Pseudouridina , RNA , Humanos , Pseudouridina/metabolismo , Processamento Pós-Transcricional do RNA
5.
Mol Divers ; 27(2): 603-618, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35635599

RESUMO

FAK (focal adhesin kinase), a tyrosine kinase, plays an imperative role in cell-cell communication, particularly in cell signaling systems. It is a multi-functional signaling protein, which integrates and transduces signals into cancer cells through growth factor receptors or integrin and its interaction with Paxillin (PAX). The molecular processes by which FAK promotes the development and progression of cancer have progressively established the possible relationship between FAK-PAX complex in many types of cancer. The interaction of FAX and PAX is very important in breast cancer and thus acts as an essential biomarker for drugs, vaccines or peptide inhibitor designing. In this regard, computational approaches, particularly peptide designing to target the binding interface of the interacting partners, would greatly assist the design of peptide inhibitors against various cancer. Accordingly, in this present study, we screened 236 experimentally validated anti-breast cancer peptides using computational drugs repositioning approach to design peptides targeting the FAK-PAX complex. Using protein-peptide docking the binding site for the HP1 was confirmed and a total of 236 anti-breast cancer peptides were screened. Among the 236, only 12 peptides reported a docking score better than the control. From these 12, Magainin with the docking score - 103.8 ± 10.3 kcal/mol, NRC-07 with the docking score - 100.8 ± 16.5 kcal/mol, and Indolicidin with the docking score - 101.7 ± 3.9 kcal/mol, peptides potentially inhibit the FAX-PAX binding. Calculation of protein's motion and FEL revealed the binding and inhibitory behavior. Moreover, binding free energy (MM/GBSA) confirmed that Magainin exhibited the total binding energy - 53.28 kcal/mol, NRC-07 possessed the TBE - 44.16 kcal/mol, and Indolicidin reported the TBE of - 40.48 kcal/mol, thus explaining the inhibitory potential of these peptides. In conclusion, these peptides exhibit strong inhibitory potential and could abrogate the FAK-PAX complex in in vitro models and thus may relieve the burden of breast cancer.


Assuntos
Neoplasias da Mama , Reposicionamento de Medicamentos , Humanos , Feminino , Paxilina/metabolismo , Magaininas/metabolismo , Neoplasias da Mama/tratamento farmacológico , Proteínas Tirosina Quinases , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular
6.
Parasitol Res ; 122(9): 2135-2145, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37466666

RESUMO

Tropical theileriosis is a tick-borne disease caused by the protozoan Theileria annulata and transmitted by numerous species of Ixodid ticks of the genus Hyalomma. The main clinical signs are fever, lymphadenopathy, and anemia responsible for heavy economic losses, including mortality, morbidity, vaccination failure, and treatment cost. Development of poor cell-mediated immunity (CMI) has been observed in the case of many bovine pathogens (bacteria, viruses, and parasites). Quantification of CMI is a prerequisite for evaluating vaccine efficacy against theileriosis caused by T. annulata. The current study evaluated the CMI in calves administered with two types of T. annulata vaccine (live attenuated and killed). We prepared a live attenuated T. annulata vaccine by attenuation in a rabbit model and also prepared killed vaccine from non-attenuated T. annulata. For the evaluation of immune response in experimental groups including control, 20 calves were divided into four different groups (A, B, C, and D). They were either inoculated subcutaneously with live rabbit-propagated-Theileria-infected RBCs (5 × 106) (group A) or with killed T. annulata vaccine (2 × 109 schizonts) with Freund's adjuvant (group B), along with an infected group (group C) and a healthy control group (group D). The protection of vaccinated calves was estimated with challenge infection. Our results showed that with a single shot of live-attenuated and killed vaccine with a booster dose elicited cell-mediated immune responses in immunized calves. We observed a significant elevation in CD4 + and CD8 + T cells in immunized calves. A significant difference in the CD8 + T cell response between the post-challenge stage of killed and live vaccine (p < 0.0001) was observed, whereas no other difference was found at both pre- and post-immunization stages. A similar finding was recorded for the CD4 + T cells at a post-challenge stage, where a significant difference was seen between killed and live vaccine (p < 0.0001). Another significant difference was observed between the CD8 + T cells and CD4 + T cells at the post-challenge stage in the live vaccine group, where there was a significantly higher induction of CD4 + T cell response (p < 0.0001).


Assuntos
Doenças dos Bovinos , Ixodidae , Vacinas Protozoárias , Theileria annulata , Theileriose , Animais , Bovinos , Coelhos , Theileriose/prevenção & controle , Theileriose/parasitologia , Vacinas de Produtos Inativados , Imunização/veterinária , Doenças dos Bovinos/parasitologia , Imunidade Celular
7.
Microb Pathog ; 168: 105592, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35595178

RESUMO

Heartland virus is a single-stranded negative-sense RNA virus that infects humans and causes lethargy, myalgia, headaches, nausea, diarrhea, weight loss, arthralgia, loss of appetite, leukopenia, and easy bruising due thrombocytopenia. The unavailability of antiviral drugs for HRTV infection is a major obstacle to treat this infection, therefore supportive care management is adopted in the case of a severe ailment. In this scientific study, proteins specific and proteome-wide Helper T-cell (HTL), linear B cell, and cytotoxic T-cell (CTL) epitopes mapping joined together with suitable linkers to design multi-epitopes subunit vaccine (MEVC). The constructed four vaccines from nucleocapsid protein, replicase, glycoprotein and finally whole proteome-wide constructs demonstrated stronger antigenic and non-allergenic behavior. Physiochemical properties evaluation also reported easy and efficient expression and downstream analysis of the constructs. Molecular docking of these constructs with toll-like receptor 7 (TLR7) revealed good binding and further validation based on MM/GBSA also demonstrated stronger interaction between the vaccine constructs and TLR7. Moreover, in silico cloning reported CAI value of 0.96 for each construct and excellent GC contents percentage required for experimental analysis. Furthermore, immune simulation-based immune response surveillance revealed that upon the injection of antigen the primary and secondary antibodies were produced between 5 and 15 days, and a more robust neutralization of the antigen by the proteome-wide vaccine construct was observed. This research could pave the way for the development of dynamic and efficient vaccines that contain a unique mix of numerous HRTV derived antigenic peptides to control HRTV infection.


Assuntos
Proteoma , Vacinologia , Biologia Computacional , Epitopos de Linfócito B , Epitopos de Linfócito T , Humanos , Simulação de Acoplamento Molecular , Receptor 7 Toll-Like , Vacinas de Subunidades Antigênicas
8.
J Org Chem ; 87(6): 4088-4096, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35213165

RESUMO

We report a simple, efficient, and highly selective C-H bond insertion of copper carbenes generated in situ from 4-diazo-1,4-dihydroisoquinolin-3-ones into ß-C(sp2)-H bonds of N-sulfonyl enamides, which gave a series of 4-(1,4,5,6-tetrahydropyridin-3-yl)-1,4-dihydroisoquinolin-3(2H)-ones in good to excellent yields. Operationally simple and mild reaction conditions, a cheap catalyst, readily accessible starting materials, and a broad substrate scope are the merits of this reaction.

9.
J Org Chem ; 87(23): 15938-15946, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36397214

RESUMO

Herein, we report an unexpected cascade ring expansion/annulation reaction between 4-diazo-1,4-dihydroisoquinolin-3-ones and a variety of isatin derivatives in the presence of Sc(OTf)3 catalyst. A series of novel indolobenzazepinones were synthesized in good to excellent yields with the exclusion of nitrogen and carbon dioxide gases. High bond-forming efficiency, novel reaction mechanism, readily available starting materials, commercially available cheap catalyst, broad substrate scope, and mild reaction conditions are the prominent features of this method.

10.
Org Biomol Chem ; 20(9): 1900-1906, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35166740

RESUMO

Herein, we report a C-H bond functionalization strategy for the construction of oxo- and aza-spirocyclic compounds from diazo compounds as coupling partners. Our method comprises ortho sp2 C-H bond activation of arylacyl ammonium salts, followed by coupling with two types of cyclic diazo compounds i.e. 4-diazoisochroman-3-imines and 4-diazoisoquinolin-3-ones, respectively. The mechanism involves the formation of dual metal carbene intermediates in situ with the breakage of oxidizing C-N bonds in arylacyl ammonium salts. The cascade C-H activation/annulation process gave a variety of novel spiro[indene-1,4'-isochromane]-3,3'(2H)-diones and spiro[indene-1,4'-isoquinoline]-3,3'(2H)-diones in good to excellent yields. Readily available starting materials, broad substrate scope, and operationally simple and mild reaction conditions are the prominent features of this method.

11.
Financ Res Lett ; 49: 103095, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36119916

RESUMO

This paper explores the impacts of the COVID-19 pandemic on the global green bond and conventional assets, including commodity, treasury, stock and clean energy markets, using Diebold and Yilmaz (2012) and Baruník and Krehlík, 2018b spillover framework. The results show that spillover transmitted from COVID-19 is relatively strong over a medium- and long-term horizon, and the spillover effects sharply increased when the pandemic became severe. Furthermore, green bonds are most affected by the COVID-19 pandemic, followed by the treasury, while the other conventional assets are only slightly affected. Additionally, our findings also contain a low-risk portfolio during COVID-19 pandemic.

12.
J Cell Physiol ; 236(10): 7045-7057, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33755190

RESUMO

The evolution of the SARS-CoV-2 new variants reported to be 70% more contagious than the earlier one is now spreading fast worldwide. There is an instant need to discover how the new variants interact with the host receptor (ACE2). Among the reported mutations in the Spike glycoprotein of the new variants, three are specific to the receptor-binding domain (RBD) and required insightful scrutiny for new therapeutic options. These structural evolutions in the RBD domain may impart a critical role to the unique pathogenicity of the SARS-CoV-2 new variants. Herein, using structural and biophysical approaches, we explored that the specific mutations in the UK (N501Y), South African (K417N-E484K-N501Y), Brazilian (K417T-E484K-N501Y), and hypothetical (N501Y-E484K) variants alter the binding affinity, create new inter-protein contacts and changes the internal structural dynamics thereby increases the binding and eventually the infectivity. Our investigation highlighted that the South African (K417N-E484K-N501Y), Brazilian (K417T-E484K-N501Y) variants are more lethal than the UK variant (N501Y). The behavior of the wild type and N501Y is comparable. Free energy calculations further confirmed that increased binding of the spike RBD to the ACE2 is mainly due to the electrostatic contribution. Further, we find that the unusual virulence of this virus is potentially the consequence of Darwinian selection-driven epistasis in protein evolution. The triple mutants (South African and Brazilian) may pose a serious threat to the efficacy of the already developed vaccine. Our analysis would help to understand the binding and structural dynamics of the new mutations in the RBD domain of the Spike protein and demand further investigation in in vitro and in vivo models to design potential therapeutics against the new variants.


Assuntos
Mutação/genética , SARS-CoV-2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Brasil , COVID-19/metabolismo , Humanos , Ligação Proteica/genética , África do Sul , Reino Unido , Virulência/genética
13.
Microb Pathog ; 152: 104771, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33524568

RESUMO

Mycoplasma genitalium is a small size, sexually transmitted bacterial pathogen that causes urethritis in males and cervicitis in females. Being resistant to antibiotics, difficulty in diagnosis, treatment, and control of this cosmopolitan infection, vaccination is the alternating method for its effective management. Herein, this study was conducted to computationally design a multi-epitope vaccine to boost host immune responses against M. genitalium. To achieve the study aim, immunoinformatics approaches were applied to the said pathogen's proteomics sequence data. B and T cell epitopes were projected from the three shortlisted vaccine proteins; MG014, MG015, Hmw3MG317. The final vaccine ensemble comprises cytotoxic and helper T cell epitopes fused through appropriate linkers. The epitopes peptide is then liked to an adjuvant for efficient recognition and processing by the host immune system. The various physicochemical parameters such as allergenicity, antigenicity, theoretical pI, GRAVY, and molecular weight of the vaccine were checked and found safe and effective to be used in post-experimental studies. The stability and binding affinity of the vaccine with the TLR1/2 heterodimer were ensured by performing molecular docking. The best-docked complex was considered, ranked top having the lowest binding energy and strong intermolecular binding and stability. Finally, the vaccine constructs better expression was obtained by in silico cloning into the pET28a (+) vector in Escherichia coli K-12 strain, and immune simulation validated the immune response. In a nutshell, all these approaches lead to developing a multi-epitope vaccine that possessed the ability to induce cellular and antibody-mediated immune responses against the pathogen used.


Assuntos
Escherichia coli K12 , Infecções por Mycoplasma , Mycoplasma genitalium , Vacinas Bacterianas , Biologia Computacional , Epitopos de Linfócito B , Epitopos de Linfócito T , Feminino , Humanos , Imunidade , Simulação de Acoplamento Molecular , Infecções por Mycoplasma/prevenção & controle , Mycoplasma genitalium/genética , Proteoma , Vacinas de Subunidades Antigênicas
14.
J Org Chem ; 86(1): 455-465, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33325697

RESUMO

A novel method has been developed to synthesize a unique class of highly functionalized isochromeno[4,3-c]pyridazines. This reaction features an intermolecular functionalization of terminal nitrogen atom of diazo group of 4-diazoisochoman-3-imine with two dimethylsulfonium ylide components, followed by a base promoted 6-exo-trig cyclization step. Readily available starting materials, a broad substrate scope, and operationally simple, mild, and catalyst-free reaction conditions are the prominent features of this method.

15.
J Org Chem ; 86(12): 8101-8111, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34060831

RESUMO

A visible-light-driven photoredox reaction of tetrahydroisoquinoline with 2H-azirines is described. 4,7-Bis(4-methoxyphenyl)benzo[c][1,2,5]thiadiazole, a benzothiadiazole (BTD) derived fluorophore, is used as an organic photoredox catalyst, and the reaction offers an efficient access to 5,6-dihydroimidazo[2,1-a]isoquinolines with a broad range of functional groups. The resulting 5,6-dihydroimidazo[2,1-a]isoquinolines present strong photoluminecence in solutions and powders and could be applied in the fabrication of blue OLED devices.

16.
Org Biomol Chem ; 19(28): 6341-6345, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34231621

RESUMO

Facile synthesis of 4-allyl-/4-allenyl-4-(arylthio)-1,4-dihydroisoquinolin-3-ones via the visible-light-induced Doyle-Kirmse reaction of 4-diazo-1,4-dihydroisoquinolin-3-ones with allyl-/propargyl sulfides is reported. The reaction proceeds via the generation of free carbenes from cyclic diazo compounds followed by in situ formation of sulfonium ylide intermediates, which subsequently undergo [2,3-sigmatropic rearrangement] to give highly functionalized dihydroisoquinolinones in moderate to good yields. Broad substrate scope, and catalyst-free and mild conditions are the merits of this reaction.

17.
J Pak Med Assoc ; 71(4): 1258-1259, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34125784

RESUMO

We report a case of mixed germ cell tumour, which presented with acute kidney injury in an unmarried 22-year-old Asian girl. The case demonstrated that an aggressive approach with multidisciplinary teamwork ascertained outstanding clinical outcome. The patient was successfully managed fertility-sparing surgery and three cycles of Bleomycin, Etoposide and Cisplatin (BEP) therapy. The patient's pathophysiology returned to normal within weeks and she was declared tumour-free. Furthermore, three-year follow up scans and biomarkers were evident for tumour negativity.


Assuntos
Injúria Renal Aguda , Anestésicos , Neoplasias Embrionárias de Células Germinativas , Neoplasias Ovarianas , Injúria Renal Aguda/etiologia , Adulto , Anestésicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Humanos , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Neoplasias Embrionárias de Células Germinativas/cirurgia , Neoplasias Ovarianas/tratamento farmacológico , Resultado do Tratamento , Adulto Jovem
18.
Org Biomol Chem ; 18(38): 7671-7676, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32966526

RESUMO

A facile and efficient method for the synthesis of novel 2-substituted 4-tosyl-4,5-dihydrooxazolo[5,4-c]isoquinolines from 4-diazoisoquinolin-3-ones and nitriles is reported. The reaction proceeded through a TfOH-promoted formal [3 + 2] cycloaddition and the products could be conveniently converted to 2-aryloxazolo[5,4-c]isoquinolines and the subsequent 2-(oxazolo[5,4-c]isoquinolin-2-yl)phenol which emitted bright green light in dilute dichloromethane solution and in solid form as well. Simple operation, metal-free and mild reaction conditions, short reaction time and broad substrate scope are the prominent features of this methodology.

19.
J Therm Biol ; 91: 102635, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32716877

RESUMO

Modeling and simulation of the temperature distribution, the mass concentration, and the heat transfer in the breast tissue are hot issues in magnetic fluid hyperthermia treatment of cancer. The breast tissue can be visualized as a porous matrix with saturated blood. In this paper, 3D in silico study of breast cancer hyperthermia using magnetic nanoparticles (MNPs) is conducted. The 3D FEM models are incorporated to investigate the infusion and backflow of nanofluid in the breast tumor, the diffusion of nanofluid, temperature distribution during the treatment, and prediction of the fraction of tumor necrosis while dealing with the thermal therapy. All the hyperthermia procedures are simulated and analyzed on COMSOL Multiphysics. The sensitivity of frequency and amplitude of the applied magnetic field (AMF) is investigated on the heating effect of the tumor. The mesh dependent solution of Penne's bioheat model is also analyzed. The simulated results demonstrate successful breast cancer treatment using MNPs with minimum side effects. Validation of current simulations results with experimental studies existing in literature advocates the success of our therapy. The increase in the amplitude and frequency of the AMF increases of the temperature in the tumor. The variation of mesh from coarser to finer increased the temperature through small fractions. We have also simulated the magnetic induction problem where the magnetic field is generated by current-carrying coil conductors induce heat in nearby breast tumors due to excitation of MNPs by magnetic flux. This research will aid treatment protocols and real-time clinical breast cancer treatments.


Assuntos
Neoplasias da Mama/terapia , Simulação por Computador , Hipertermia Induzida/métodos , Nanopartículas de Magnetita/uso terapêutico , Glândulas Mamárias Humanas/fisiopatologia , Condutividade Térmica , Neoplasias da Mama/fisiopatologia , Feminino , Humanos , Imageamento Tridimensional , Campos Magnéticos
20.
J Biol Chem ; 293(25): 9747-9758, 2018 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-29743236

RESUMO

Resistance to apoptosis and uncontrolled proliferation are two hallmarks of cancer cells. p53 is crucial for apoptosis triggered by a broad range of stresses and a well-known gatekeeper for neoplastic transformation. Here we show that oncogenic IDH1 R132H/R132Q mutants robustly inhibit p53 expression and such an effect is attributed to 2-HG production. Mechanistically, 2-hydroxyglutarate (2-HG) stabilizes hypoxia-inducible factor-2α, which in turn activates the expression of miR-380-5p, a characterized microRNA against p53 expression. Rescue expression of p53 can inhibit the proliferation rate and impair the resistance of apoptosis induced by doxorubicin in IDH1 R132Q mouse embryonic fibroblast cells. Furthermore, p53 protein levels correlates negatively with IDH1 R132H levels in human glioma samples. Our results thus shed a new light on how p53 is down-regulated by 2-HG and suggests that impairment of p53-mediated apoptosis contributes to the tumorigenesis driven by IDH1 mutants.


Assuntos
Arginina/genética , Neoplasias Encefálicas/patologia , Regulação Neoplásica da Expressão Gênica , Glioma/patologia , Isocitrato Desidrogenase/metabolismo , Mutação , Proteína Supressora de Tumor p53/metabolismo , Animais , Arginina/química , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Carcinogênese , Proliferação de Células , Glioma/genética , Glioma/metabolismo , Glutaratos/farmacologia , Humanos , Isocitrato Desidrogenase/genética , Camundongos , MicroRNAs/genética , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética , Ensaios Antitumorais Modelo de Xenoenxerto
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