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1.
Adv Biol (Weinh) ; 8(3): e2300399, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38053236

RESUMO

Ethyl methanesulphonate (EMS), is a widely used chemical mutagen that causes high-frequency germline null mutation by inserting an alkyl group into the nucleotide guanine in eukaryotic cells. The effect of EMS on the dynamics of the aneuploid genome, increased cellular instability, and carcinogenicity in relation to benign and malignant tumors are reported, but the molecular level understanding of morphological changes of higher-order chromatin structure has poorly been understood. This is due to a lack of sufficient resolution in conventional microscopic techniques to see small structures below the diffraction limit. Here, using super-resolution radial fluctuation, a largely fragmented, decompaction, and less dense heterochromatin structure upon EMS treatment to HEK 293A cells without any change in nuclear DNA domains is observed. This result suggests an early stage of carcinogenicity happened due to the point mutation. In addition, the distinct structural changes with an elongated morphology of lysosomes are also observed. On the other hand, fragmented and increased heterogeneous populations with an increased cytoplasmic occupancy of mitochondria are observed.


Assuntos
Microscopia , Mutação Puntual , Microscopia/métodos , Organelas , DNA/química , Heterocromatina
2.
Chem Commun (Camb) ; 59(90): 13454-13457, 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37882736

RESUMO

Herein, we report new red emissive highly photostable and water-soluble carbon nanodots (TPP CNDs) to visualize mitochondrial dynamics using super-resolution radial fluctuations (SRRF) microscopy. The TPP CNDs were synthesized in a one-step method, using 3-(carboxypropyl)triphenylphosphonium bromide (TPP) and o-phenylenediamine (OPDA) as precursors. The obtained crystal structure, NMR, and mass data suggested the presence of [3-(1H-benzimidazol-2-yl)propyl](triphenyl)phosphonium bromide (C28H26N2P+Br-) as a molecular fluorophore (MF) on the surface of the TPP CNDs. The TPP CNDs showed better photostability than the commercially available MitoTracker™ Green and were highly capable for long-term imaging of mitochondrial fission during hyperglycemic conditions and structural changes upon an antidiabetic drug treatment, without altering their fluorescence nature.


Assuntos
Brometos , Carbono , Carbono/química , Corantes Fluorescentes/química , Microscopia de Fluorescência/métodos , Mitocôndrias
3.
Environ Sci Pollut Res Int ; 30(14): 39653-39665, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36598719

RESUMO

Degradation of grease waste remains a challenging task. Current work deals with the biotransformation of grease waste into fatty acids under submerged fermentation using Penicillium chrysogenum SNP5 through media formulation and artificial neural network (ANN). Fermentation media was formulated to ameliorate the uptake of hydrocarbon by enhancing alkane hydroxylase (AlkB) activity, extracellular release of fatty acids and inhibiting beta-oxidation of fatty acid by regulating transketolase. Further, the process parameters of fermentation were optimized through Artificial Neural Network (ANN) using three critical variables viz; inoculum size (spores/ml), pH, and incubation time (days) while media engineering was done with the optimal supplementation of various medium components such as glucose, YPD, MnSO4, tetrahydrobiopterin (THB) and phloretin. The maximum conversion of 66.5% of grease waste into fatty acid was achieved at optimum conditions: inoculums size 3.36 × 107 spores/ml, incubation time 11.5 days, pH 7.2 along with formulated media composed of 1% grease in czapek-dox medium supplemented with 55.5 mM glucose, 0.5% YPD, 16.6 mM hexadecane, 1 mM MnSO4, 1 mM THB, and 1 mM phloretin. The presence of long-chain fatty acids in purified extracts such as oleic acid and octadecanoic acid as end products has valued the evolved process as another source of alternative fuel.


Assuntos
Penicillium chrysogenum , Penicillium chrysogenum/metabolismo , Ácidos Graxos/metabolismo , Fermentação , Biotransformação , Redes Neurais de Computação , Hidrocarbonetos/metabolismo , Glucose/metabolismo
4.
Biomater Sci ; 10(16): 4525-4537, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35788579

RESUMO

Doxorubicin is an anthracycline drug most commonly used in cancer therapy. It intercalates with the nuclear DNA and induces toxicity by causing DNA breaks and histone eviction. However, the kinetics of its action on the nucleus has not been mapped effectively. This study shows successful PEGylation and DOX loading through π-π interaction onto carbogenic fluorescent nanodots (FNDs), which have an affinity for the nucleolus. Then the drug release from the nanoparticle and its action on the nuclear environment were aptly mapped using both fluorescence lifetime imaging and superresolution radial fluctuation (SRRF) techniques. Here for the first time, the nuclear degradation kinetics caused by the released DOX from the FNDs as a result of DNA double-strand breaks and histone eviction was visualized. This led to the observation of decreasing length, breadth, and complex structure of the nuclear clusters from 6 h to 24 h, resulting in isolated cluster visualization. However, the superresolution images for free DOX and untreated cells reveal no such drastic effects at the same concentration and time points, unlike DOX loaded particles.


Assuntos
Doxorrubicina , Histonas , DNA , Fragmentação do DNA , Doxorrubicina/química , Microscopia Confocal , Polietilenoglicóis/química
5.
Biochem Biophys Res Commun ; 620: 8-14, 2022 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-35772213

RESUMO

The high mutability of the SARS-CoV-2 virus is a growing concern among scientific communities and health professionals since it brings the effectiveness of repurposed drugs and vaccines for COVID-19 into question. Although the mutational investigation of the Spike protein of the SARS-CoV-2 virus has been confirmed by many different researchers, there is no thorough investigation carried out at the interacting region to reveal the mutational status and its associated severity. All the energetically favorable mutations and their detailed analytical features that could impact the infection severity of the SARS-CoV-2 virus need to be identified. Therefore, we have thoroughly investigated the most important site of the SARS-CoV-2 virus, which is the interface region (Residue 417-505) of the virus Spike that interacts with the human ACE2 receptor. Further, we have utilized molecular dynamic simulation to observe the relative stability of the Spike protein with partner ACE2, as a consequence of these mutations. In our study, we have identified 52 energetically favorable Spike mutations at the interface while binding to ACE2, of which only 36 significantly enhance the stabilization of the Spike-ACE2 complex. The stability order and molecular interactions of these mutations were also identified. The highest stabilizing mutation V503D confirmed in our study is also known for neutralization resistance.


Assuntos
COVID-19 , SARS-CoV-2 , Enzima de Conversão de Angiotensina 2/genética , COVID-19/genética , Vacinas contra COVID-19 , Humanos , Simulação de Dinâmica Molecular , Mutação , Peptidil Dipeptidase A/metabolismo , Ligação Proteica , Receptores Virais/metabolismo , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/química
6.
Expert Rev Proteomics ; 17(1): 85-94, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31968176

RESUMO

Background: Helminth infections cause widespread morbidity and are a significant global disease burden. One among them is Neurocysticercosis, a central nervous system infection caused by the larvae Taenia solium, leading to epilepsy. Helminths are strong immune modulators and can survive for a long time in adverse host environments. Kinases are molecular switches and are essential to initiate/propagate signaling cascades and are detrimental to the regulation of homeostasis. They have been implicated in the progression of many diseases and are potentially lucrative drug targets.Objective: To identify kinases in T. solium proteome and prioritize them as drug targets.Methodology: A Hidden Markov Model (HMM) was used to curate and classify kinases into families based on sequence homology to model organisms followed by phylogenetic analysis of each family. To predict potential drug targets, kinases were identified based on a homologically lethal relationship to C. elegans but non-lethal to humans. Kinases thus selected were searched for matching ligands in SARFkinase and DrugBank databases.Result and conclusion: T. solium kinases make up 1.8% of its proteome, CMGC is the largest kinase family and RGC is the smallest and catalytically inactive family. We predict 23-potential kinases to be drug targets for T. solium.[Figure: see text].


Assuntos
Descoberta de Drogas/métodos , Proteínas de Helminto/metabolismo , Proteínas Quinases/química , Proteoma/química , Proteômica/métodos , Taenia solium/metabolismo , Animais , Anti-Helmínticos/química , Anti-Helmínticos/farmacologia , Proteínas de Helminto/química , Cadeias de Markov , Ligação Proteica , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/metabolismo , Proteoma/metabolismo , Taenia solium/efeitos dos fármacos
7.
Expert Rev Vaccines ; 19(1): 105-114, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31971446

RESUMO

Objective: Taenia solium is a neglected tropical disease; larvae of this parasite infect central nervous system i.e. Neurocysticercosis, and adults mature and survive into intestine i.e. Taeniasis. Globally more than 50 million people are at the risk of infection. This is one of the main etiological agents for onset of new early epilepsy in developing countries. However, there is no vaccine available to protect human from its infection. Hence, there is an urgent need for a good vaccine.Methods: We applied immune-informatics approach to design a multi-epitope chimeric vaccine consisting of both B and T-cell epitopes.Results: From the whole transcriptome of Taenia, we identified five suitable peptides present on cell membrane, epitope identification on these peptides were done by using various immunoinformatic software. Physiochemical properties were determined and the tertiary structure of vaccine was predicted, validated and refined, and to increase antigenicity we added linker to them. Best-modeled protein-complex was used for docking study with TLR1-2, TLR4, TLR3 and TLR7 and stability of molecular complex was determined by molecular dynamics simulation.Conclusions: Overall, we attempted to design an efficient subunit chimeric vaccine, which could stimulate humoral and cellular immune responses and could protect against both neurocysticercosis and taeniasis.


Assuntos
Neurocisticercose/prevenção & controle , Teníase/prevenção & controle , Vacinas/administração & dosagem , Animais , Simulação por Computador , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/imunologia , Humanos , Imunidade Celular , Imunidade Humoral , Simulação de Acoplamento Molecular , Neurocisticercose/imunologia , Taenia solium/imunologia , Teníase/imunologia , Vacinas/imunologia , Vacinas de Subunidades Antigênicas
8.
Artigo em Inglês | MEDLINE | ID: mdl-31867284

RESUMO

Helminthic parasitic infection is grossly prevalent across the globe and is considered a significant factor in human cancer occurrence induced by biological agents. Although only three helminths (Schistosoma haematobium, Clonorchis sinensis, and Opisthorchis viverrini) so far have been directly associated with carcinogenesis; there are evidence suggesting the involvement of other species too. Broadly, human helminthiasis can cause chronic inflammation, genetic instability, and host immune modulation by affecting inter- and intracellular communications, disruption of proliferation-anti-proliferation pathways, and stimulation of malignant stem cell progeny. These changes ultimately lead to tumor development through the secretion of soluble factors that interact with host cells. However, the detailed mechanisms by which helminths introduce and promote malignant transformation of host cells are still not clear. Here, we reviewed the current understanding of immune-pathogenesis of helminth parasites, which have been associated with carcinogenesis, and how these infections initiate carcinogenesis in the host.


Assuntos
Helmintíase/complicações , Helmintíase/parasitologia , Helmintos/fisiologia , Inflamação/etiologia , Neoplasias/etiologia , Animais , Transformação Celular Neoplásica , Doença Crônica , Suscetibilidade a Doenças , Helmintíase/epidemiologia , Interações Hospedeiro-Parasita/imunologia , Humanos , Evasão da Resposta Imune , Imunomodulação , Inflamação/epidemiologia , Inflamação/metabolismo , Inflamação/patologia , Doenças Negligenciadas , Neoplasias/epidemiologia , Neoplasias/metabolismo , Neoplasias/patologia
9.
Asian Pac J Cancer Prev ; 19(2): 421-425, 2018 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-29479992

RESUMO

Background: With acute myeloid leukemia (AML), there are limited data about the accuracy of day 14 bone marrow (BM) biopsies for predicting complete remission as compared to day 28 BM biopsy results. We here aimed to estimate the correlation between, and the diagnostic accuracy of, both approaches. Materials and Methods: We reviewed 84 patients with AML treated with standard induction chemotherapy to evaluate the remission rate and treatment decisions based on day 14 BM biopsy from 2000-2012. Results: Sixty five patients (77%) demonstrated remission (CR) with less than 5% blasts on their day 14 BM. Thirteen patients (16%) had residual disease (RD), and 6 (7%) were classified as indeterminate response (IR) i.e., blasts 5-20%. Two patients with RD on day 14 underwent re-induction. Out of the 17 remaining cases with RD+IR, 14 (all 6 with IR and 8 out of 11 with residual disease with no re-induction) demonstrated a morphologic complete remission (CR) on day 28 BM. The percentages for complete remissions on days 28 and 14 were significantly different [94% versus 79.3%, respectively; p=0.004, (OR= 0.143, 95% CI: 0.032-0.63)]. Day 14 BM had 82% sensitivity in predicting CR on Day 28; however, it had insufficient specificity (60%) in predicting failure of CR. Conclusions: Induction treatment response assessment based on day 14 BM does not accurately predict the response rate on day 28 and the use of day 14 BM as a sole marker of response to therapy might expose patients to unnecessary interventions.


Assuntos
Medula Óssea/cirurgia , Técnicas de Apoio para a Decisão , Quimioterapia de Indução , Leucemia Mieloide Aguda/tratamento farmacológico , Neoplasia Residual/tratamento farmacológico , Indução de Remissão , Adolescente , Adulto , Idoso , Biópsia , Medula Óssea/patologia , Feminino , Seguimentos , Humanos , Leucemia Mieloide Aguda/patologia , Masculino , Pessoa de Meia-Idade , Neoplasia Residual/patologia , Prognóstico , Fatores de Tempo , Adulto Jovem
10.
Am J Hematol ; 93(2): 286-295, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28971501

RESUMO

Philadelphia chromosome-positive (Ph-positive) acute lymphoblastic leukemia (ALL) is a biologically, clinically, and genetically distinct subtype of precursor-B ALL. The Ph chromosome, results from a reciprocal translocation of the ABL1 kinase gene on chromosome 9 to the breakpoint cluster region (BCR) gene on chromosome 22. Depending on the translocation breakpoint, typically a p210 BCR-ABL1 or a p190 BCR-ABL onc protein are generated; both are constitutively active tyrosine kinases that play a central role to alter signaling pathways of cell proliferation, survival, and self-renewal, leading to leukemogenesis. In Ph-positive ALL, the p190-BCR-ABL (minor [m]-bcr) subtype is more frequent than the p210-BCR-ABL (major [M]-bcr) subtype, commonly found in chronic myeloid leukemia. The Philadelphia chromosome is the most frequent recurrent cytogenetic abnormality in elderly patients with ALL. Its incidence increases with age, reaching ∼50% in patients with ALL aged 60 years and over. Patients traditionally had a very poor outcome with chemotherapy, particularly if they do not undergo allogeneic hematopoietic cell transplantation (allo-HCT) in first complete remission (CR1). With the availability of multiple tyrosine kinase inhibitors (TKI), the therapeutic armamentarium is expanding quickly. However, there is no consensus on how to best treat Ph-positive ALL. With modern therapy, improved outcomes have led to the emergence of a number of controversies, including the need for intensive chemotherapy, the ideal TKI, and whether all eligible patients should receive an allo-HSCT, and if so, what type. Here, we discuss these controversies in light of the available literature.


Assuntos
Cromossomo Filadélfia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adulto , Gerenciamento Clínico , Proteínas de Fusão bcr-abl/genética , Humanos
11.
Bioresour Technol ; 213: 262-269, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27013189

RESUMO

In this study Bacillus sp. MTCC5877 was explored for the production of biosurfactant (BSs) and various carbon sources 1% (w/v), 0.5% (w/v) nitrogen sources were tested at different pH, and temperature. Yield was measured in terms of Emulsification index (EI), Oil Displacement Area (ODA) and Drop Collapse Area (DCA) and maximum emulsification activities of BSs were found (E24) 50%, 76% and 46%, respectively, and maximum ODA of 5.0, 6.2 and 4.7cm, were shown respectively. The BS was able to reduce the surface tension of water from 72 to 30mN/m and 72 to 32mN/m. Structural compositions of BS were confirmed by FTIR, GC-MS and NMR. Anti-adhesive property of BS was determined and found effective against biofilm formation. It could remove 73% Cd from vegetable which confirms its application in food industry.


Assuntos
Bacillus/metabolismo , Biotecnologia/métodos , Indústria Alimentícia/métodos , Tensoativos/química , Tensoativos/metabolismo , Cádmio/isolamento & purificação , Carbono/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Nitrogênio/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Tensão Superficial , Temperatura
12.
Asian Pac J Cancer Prev ; 14(2): 1089-92, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23621192

RESUMO

BACKGROUND: Elderly patients with acute myeloid leukemia (AML) have a poor outcome because of co- morbidities, poor tolerance to intensive chemotherapy and inherently more resistant disease. Clofarabine is a second generation nucleoside analogue which has shown promising activity in elderly patients with AML. This study was conducted to review the outcome of treatment with clofarabine in a group of such patients. METHODS: The records of 5 elderly patients who were diagnosed to have AML and treated with clofarabine over a 12 month period were reviewed retrospectively. RESULTS: There were 2 female and 3 male patients with a median age of 68 years (range 65-82). At the time of treatment, 2 patients had newly diagnosed AML not considered suitable for intensive therapy, while 3 patients had partial or no response to conventional chemotherapy. The overall response rate was 100%, all patients achieving a complete remission. Induction and consolidation were well tolerated. All patients developed neutropenia with a median duration of 20 days (range 17-42). One patient developed hand and foot syndrome and a generalized rash but recovered. There was no mortality and all patients remained in remission after a median follow-up of 5.2 months (Range 3-10). CONCLUSION: Clofarabine (alone or in combination) is active in elderly AML patients with an acceptable safety profile and should be considered a potential option in this group.


Assuntos
Nucleotídeos de Adenina/uso terapêutico , Antimetabólitos Antineoplásicos/uso terapêutico , Arabinonucleosídeos/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Nucleotídeos de Adenina/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Antimetabólitos Antineoplásicos/efeitos adversos , Arabinonucleosídeos/efeitos adversos , Clofarabina , Intervalo Livre de Doença , Feminino , Síndrome Mão-Pé , Humanos , Leucemia Mieloide Aguda/mortalidade , Masculino , Neutropenia/induzido quimicamente , Indução de Remissão , Estudos Retrospectivos , Sobrevida , Resultado do Tratamento
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