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1.
J Fluoresc ; 34(2): 609-626, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37329380

RESUMO

The present work intended to report the synthesis of newly designed donor-acceptor complexes of the pyrimidine-based system namely TAPHIA 1 and TAPHIA 2, which are symphonized to give the NLO properties. The methodologies adopted for both complexes were different and hence influenced their geometrical properties. The synthesized complexes were characterized using different techniques including SCXRD, FTIR, UV, PXRD, and TGA to confirm their formation. The SCXRD analysis revealed that TAPHIA 1 was crystallized in the Pca21 space group in an orthorhombic system while TAPHIA 2 was crystallized in the P21/c space group in a monoclinic system. The third-order NLO properties of both complexes were explored using the Z-Scan technique by employing a continuous wave (CW) diode laser of 520 nm. The third-order NLO parameters including nonlinear refractive index (n2), nonlinear absorption coefficient (ß) and nonlinear optical susceptibility (χ (3)) were calculated at different powers; 40, 50 and 60 mW at fixed solution concentration (10 mM) for both the complexes. Moreover, the experimental properties including NLO, FTIR, and UV were well corroborated with theoretical results obtained at the B3LYP-D3/6-31++G(d,p) level of theory. The analysis of the theoretical and experimental properties of both complexes suggests that TAPHIA 2 is a better applicant to be employed in optical devices than TAPHIA 1 due to the enhanced ability of internal charge transfer.

2.
Anal Biochem ; 683: 115368, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37890549

RESUMO

Hand, Foot, and Mouth Disease (HFMD) is an outbreak infectious disease that can easily spread among children under the age of five. The most common causative agents of HFMD are enterovirus 71 (EV71) and coxsackievirus A16 (CVA16), but infection caused by EV71 is more associated with fatalities due to severe neurological disorders. The present diagnosis methods rely on physical examinations by the doctors and further confirmation by laboratories detection methods such as viral culture and polymerase chain reaction. Clinical signs of HFMD infection and other childhood diseases such as chicken pox, and allergies are similar, yet the genetics and pathogenicity of the viruses are substantially different. Thus, there is an urgent need for an early screening of HFMD using an inexpensive and user-friendly device that can directly detect the causative agents of the disease. This paper reviews current HFMD diagnostic methods based on various target types, such as nucleic acid, protein, and whole virus. This was followed by a thorough discussion on the emerging sensing technologies for HFMD detection, including surface plasmon resonance, electrochemical sensor, and surface enhanced Raman spectroscopy. Lastly, optical absorption spectroscopic method was critically discussed and proposed as a promising technology for HFMD screening and detection.


Assuntos
Enterovirus Humano A , Enterovirus , Doença de Mão, Pé e Boca , Criança , Humanos , Doença de Mão, Pé e Boca/diagnóstico , Enterovirus/genética , Reação em Cadeia da Polimerase , Análise Espectral
3.
J Biomol Struct Dyn ; : 1-15, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37577966

RESUMO

Several biochemical reactions occur during the interaction of metal complexes and proteins due to conformational modifications in the structure of the protein, which provide fundamental knowledge of the effect, mechanism, and transport of many drugs throughout the body. Here, we report the synthesis, identification, and impact of the 3-dimensional Copper(II)sulfanilic acid coordination polymer (CP 1) on interactions with bovine serum albumin (BSA). The CP 1 was synthesized via a simple hot stirring method, and the single crystal XRD confirms the effective bonding interactions between metal and organic ligand, forming a crystalline polymeric chain and the topological study shows the sql type of underlying net topology. Powder XRD, Fourier transform infrared spectroscopy, and thermogravimetric analysis were also performed. Moreover, DFT/B3LYP calculations provide chemical precision for the resulting complex. Further, the changes that occur in the secondary structure of protein when CP 1 binds with BSA as well as its binding capacity were investigated via circular dichroism analysis and spectroscopic methods such as UV-absorption spectroscopy and fluorescence spectroscopy, respectively. The CP 1/BSA complex melting point was also measured, and its temperature-dependent heat denaturation was studied along with molecular docking.Communicated by Ramaswamy H. Sarma.

4.
J Biomol Struct Dyn ; : 1-13, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37578054

RESUMO

In this work, a new Cu(II)-based complex as a chemotherapeutic drug agent, formulated as[Cu(DCA)4(H2O)2]⋅4H2O⋅4MeOH, (DCA = 3,4-dimethoxycinnamic acid), namely 1 was successfully synthesized utilizing DCA as a ligand to arrest fibrillation in Human lysozyme. The 1 was thoroughly characterized by single crystal X-ray diffraction (SC-XRD), spectroscopic (UV-Vis and FTIR) techniques, PXRD, and TGA analysis. Its crystal structure reveals a paddle wheel network around central copper metal ions. The Cu(II) metal ions exhibit a distorted square pyramidal configuration. The fluorescence titration studies showed moderate binding interaction of 1 with HuL with Ka of 6.3x105 M-1 at pH-2, 25 °C due to its interaction withAsp53, Tyr63, Val110, and Ala111 as shown by docking and simulation studies. 1suppresses the HuL fibrillation in a concentration-dependent manner, as demonstrated by ThT assay. At 200 µM concentration, it leads to the formation of smaller species of the protein in comparison to the control sample, as suggested by Light Scattering studies. The species formed are less hydrophobic and retain their native α-helix structure compared to the control samples, which are hydrophobic and form ß-sheet rich amyloids as shown by ANS hydrophobicity assay and CD spectroscopy, respectively. Furthermore, morphological analysis of the species by AFM has demonstrated that, unlike mature amyloid fibrils in the control sample, HuL forms small-size aggregates in the presence of 1 under similar fibrillation conditions. It can be concluded that 1 effectively suppresses HuL fibrillation due to moderate binding to the protein.Communicated by Ramaswamy H. Sarma.

5.
Artigo em Inglês | MEDLINE | ID: mdl-36945684

RESUMO

Introduction: Magnetic hyperthermia therapy (MHT) is a minimally invasive adjuvant therapy capable of damaging tumors using magnetic nanoparticles exposed radiofrequency alternating magnetic fields. One of the challenges of MHT is thermal dose control and excessive heating in superficial tissues from off target eddy current heating. Methods: We report the development of a control system to maintain target temperature during MHT with an automatic safety shutoff feature in adherence to FDA Design Control Guidance. A proportional-integral-derivative (PID) control algorithm was designed and implemented in NI LabVIEW®. A standard reference material copper wire was used as the heat source to verify the controller performance in gel phantom experiments. Coupled electromagnetic thermal finite element analysis simulations were used to identify the initial controller gains. Results: Results showed that the PID controller successfully achieved the target temperature control despite significant perturbations. Discussion and Conclusion: Feasibility of PID control algorithm to improve efficacy and safety of MHT was demonstrated.

6.
Cancers (Basel) ; 15(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36672278

RESUMO

We present in vivo validation of an automated magnetic hyperthermia therapy (MHT) device that uses real-time temperature input measured at the target to control tissue heating. MHT is a thermal therapy that uses heat generated by magnetic materials exposed to an alternating magnetic field. For temperature monitoring, we integrated a commercial fiber optic temperature probe containing four gallium arsenide (GaAs) temperature sensors. The controller device used temperature from the sensors as input to manage power to the magnetic field applicator. We developed a robust, multi-objective, proportional-integral-derivative (PID) algorithm to control the target thermal dose by modulating power delivered to the magnetic field applicator. The magnetic field applicator was a 20 cm diameter Maxwell-type induction coil powered by a 120 kW induction heating power supply operating at 160 kHz. Finite element (FE) simulations were performed to determine values of the PID gain factors prior to verification and validation trials. Ex vivo verification and validation were conducted in gel phantoms and sectioned bovine liver, respectively. In vivo validation of the controller was achieved in a canine research subject following infusion of magnetic nanoparticles (MNPs) into the brain. In all cases, performance matched controller design criteria, while also achieving a thermal dose measured as cumulative equivalent minutes at 43 °C (CEM43) 60 ± 5 min within 30 min.

7.
Acta Crystallogr E Crystallogr Commun ; 78(Pt 6): 669-674, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36072136

RESUMO

The title compound, C4H9N5 2+·2NO3 -, crystallizes in the monoclinic crystal system, space group P21/c. The asymmetric unit, which comprises a diprotonated tri-amino-pyrimidine dication and two nitrate anions, has an almost planar geometry with a dihedral angle of 0.92 (4)° between the mean plane of the cation and that defined by both anions. In the crystal, hydrogen-bonding inter-actions between the 2,4,6-tri-amino-pyrimidine cation and the nitrate anions lead to a one-dimensional supra-molecular network with weak anionic inter-actions forming a three-dimensional network. These inter-actions were investigated using Hirshfeld surface analysis, which indicates that the most important contributions for the packing arrangement are from O⋯H/H⋯O (53.2%), N⋯H/H⋯N (12.5%) and C⋯H/H⋯C (9.6%) inter-actions. Energy framework analysis showed that of the components of the framework energies, electrostatic repulsion (E rep) is dominant.

8.
Molecules ; 27(5)2022 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-35268825

RESUMO

Here, we report a facile route to the synthesizing of a new donor-acceptor complex, L3, using 4-{[(anthracen-9-yl)meth-yl] amino}-benzoic acid, L2, as donor moiety with anthraquinone as an acceptor moiety. The formation of donor-acceptor complex L3 was facilitated via H-bonding and characterized by single-crystal X-ray diffraction. The X-ray diffraction results confirmed the synthesized donor-acceptor complex L3 crystal belongs to the triclinic system possessing the P-1 space group. The complex L3 was also characterized by other spectral techniques, viz., FTIR and UV absorption spectroscopy, which confirmed the formation of new bonds between donor L2 moiety and acceptor anthraquinone molecule. The crystallinity and thermal stability of the newly synthesized complex L3 was confirmed by powdered XRD and TGA analysis and theoretical studies; Hirshfeld surface analysis was performed to define the type of interactions occurring in the complex L3. Interestingly, theoretical results were successfully corroborated with experimental results of FTIR and UV absorption. The density functional theory (DFT) calculations were employed for HOMO to LUMO; the energy gap (∆E) was calculated to be 3.6463 eV. The complex L3 was employed as a photocatalyst for the degradation of MB dye and was found to be quite efficient. The results showed MB dye degraded about 90% in 200 min and followed the pseudo-first-order kinetic with rate constant k = 0.0111 min-1 and R2 = 0.9596. Additionally, molecular docking reveals that the lowest binding energy was -10.8 Kcal/mol which indicates that the L3 complex may be further studied for its biological applications.

9.
J Biomol Struct Dyn ; 40(1): 538-548, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-32876543

RESUMO

The formation of amyloid-like fibrils is a central problem in biophysical chemistry and medicine. Fibril formation and their deposition in various tissues and organs are associated with many human diseases. Searching for molecules able to prevent the formation of fibrils is, therefore, necessary. In this work, we examined the potential of a cocrystal (SS3) of 3-((4-(3-isocyanobenzyl) piperazine-1-yl) methy) benzonitrile with 5-hydroxy isophthalic acid, to prevent fibrillation of human serum albumin. We found that the cocrystal strongly bound to human serum albumin (HSA) with association constant (Ka) of 5.8 ± 0.7 × 105 M-1. The SS3 binding was found to cause small alterations in both secondary and tertiary structure of the protein. Transmission electron microscopy showed that the cocrystal completely prevented the formation of worm-like protofibrils by HSA at SS3/HSA molar ratio of 1:1. The molecule was found to prevent the aggregation in a concentration dependent manner. It was also observed that most of protein in the presence of SS3 remained in soluble state and the secondary structure contained native-like α-helical structure. Therefore, we conclude that the cocrystal effectively prevented conversion of HSA into worm-like protofibril. These finding suggest that combination of molecules in the form of cocrystal or other stable combination could pave a way for the development of drugs against amyloidosis.Communicated by Ramaswamy H. Sarma.


Assuntos
Hidroxiácidos , Albumina Sérica , Amiloide , Humanos , Nitrilas , Ácidos Ftálicos , Piperazina
10.
Cancer Control ; 27(1): 1073274820976594, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33297765

RESUMO

Hepatitis B reactivation (HBVr) in cancer patients is a well-established complication due to chemotherapy-induced immunosuppression. Studies have reported HBVr associated with immunosuppressive medications, such as rituximab, methotrexate, and high dose steroids. There are different risks for different types of chemotherapy with rituximab carrying one of the highest risks for hepatitis B reactivation. Tyrosine kinase inhibitors (TKIs) are the standard of care in patients with chronic myeloid leukemia (CML). The risk of HBVr in chronic myeloid leukemia has been reported in many studies, but to this date, there are no clear guidelines or recommendations regarding screening and monitoring of HBV in CML patients receiving TKIs. We conducted this review to identify the risk of HBVr in patients with CML who are treated with tyrosine kinase inhibitors. We recommend testing for HBV status in patients who are to be treated with TKIs and to consider giving prophylaxis in those who are positive for HBsAg at baseline. More studies are needed to assess the risk of reactivation in patients with Hepatitis B core antibody positive receiving TKIs. Currently, monitoring such patients for reactivation may be the best strategy.


Assuntos
Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Inibidores de Proteínas Quinases/efeitos adversos , Ativação Viral/imunologia , Antibioticoprofilaxia/métodos , Antibioticoprofilaxia/normas , Antivirais/uso terapêutico , Monitoramento de Medicamentos/normas , Antígenos de Superfície da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/isolamento & purificação , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/imunologia , Hepatite B Crônica/prevenção & controle , Hepatite B Crônica/virologia , Humanos , Hospedeiro Imunocomprometido , Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Programas de Rastreamento/normas , Programas de Rastreamento/estatística & dados numéricos , Guias de Prática Clínica como Assunto , Ativação Viral/efeitos dos fármacos
11.
Case Rep Oncol ; 13(2): 675-679, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32774255

RESUMO

Essential thrombocythemia (ET) is one of the myeloproliferative neoplasms, characterized by persistent thrombocytosis, platelets >450,000/µL, and evident clonal abnormalities like JAK2 V617F, MPL, CALR mutation and not fulfilling WHO criteria for MDS, CML, PV, and IDA. Here we report a 24-year-old female who presented with headache and was found to have thrombocytosis with a platelet count of 2,141 × 103/µL, diagnosed as ET as per WHO criteria 2008; she required ICU admission and thrombocytapheresis with a favorable outcome.

12.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 5): 728-731, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32431941

RESUMO

The title compound, C22H17NO2·C3H7NO, was synthesized by condensation of an aromatic aldehyde with a secondary amine and subsequent reduction. It was crystallized from a di-methyl-formamide solution as a monosolvate, C22H17NO2·C3H7NO. The aromatic mol-ecule is non-planar with a dihedral angle between the mean planes of the aniline moiety and the methyl anthracene moiety of 81.36 (8)°. The torsion angle of the Car-yl-CH2-NH-Car-yl backbone is 175.9 (2)°. The crystal structure exhibits a three-dimensional supra-molecular network, resulting from hydrogen-bonding inter-actions between the carb-oxy-lic OH group and the solvent O atom as well as between the amine functionality and the O atom of the carb-oxy-lic group and additional C-H⋯π inter-actions. Hirshfeld surface analysis was performed to qu-antify the inter-molecular inter-actions.

13.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 1): 62-65, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31921453

RESUMO

In the mol-ecule of the title anthracene derivative, C22H17NO2, the benzene ring is inclined to the mean plane of the anthracene ring system (r.m.s. deviation = 0.024 Å) by 75.21 (9)°. In the crystal, mol-ecules are linked by pairs of O-H⋯O hydrogen bonds, forming classical carb-oxy-lic acid inversion dimers with an R 2 2(8) ring motif. The dimers are linked by C-H⋯π inter-actions, forming a supra-molecular framework.

14.
J Biomol Struct Dyn ; 35(15): 3412-3431, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27801287

RESUMO

In this study, a novel series of oxazoline and thiazoline were designed as inhibitors of cytochrome P450 14 alpha-sterol demethylase (CYP51) from Candida albicans and peptide deformylase (PDF) of Escherichia coli. The long chain dibromo derivative of fatty acid esters on reaction with urea and thiourea gave their corresponding oxazolines and thiazolines, respectively. All the compounds were characterized by their spectral data (IR, 1H NMR, 13C NMR and MS) and tested for antibacterial and antifungal activity by disk diffusion assay and minimum inhibitory concentration by the broth microdilution method against gram-positive and gram-negative strains of bacteria as well as fungus strains. The investigation into antimicrobial screening revealed that all the compounds were found to be potent antimicrobial agents. After calculating likeness drug properties of the compounds by Prediction of Activity Spectra for Substances software, ADMET-related descriptors were computed to predict the pharmacokinetic properties for the active and bioavailable compounds by discovery studio 2.5. Molecular docking studies have been performed on PDF of E. coli and CYP 450-14DM of C. albicans to understand the mode of binding of the molecules in the active site of the receptor. Compounds (2-amino-5-(carbomethoxyoctyl)-1,3-oxazoline, 2-amino-5-(carbomethoxyoctyl)-1,3-thiazoline and 2-amino-4-pentyl-5-[(8'R)-8' hydroxy (carbomethoxydecyl)-1,3-oxazoline) showed excellent antimicrobial activity nearly equivalent to the control compounds and compounds, 2-amino-4-octyl-5-(carbomethoxyheptyl)-1,3-oxazolin, 2-amino-4-(2'R)(2'-hydroxy octyl)-5-(carbomethoxyheptyl)-1,3-oxazoline and 2-amino-4-pentyl-5-[(8'R)-8'-hydroxy(carbomethoxy decyl)-1,3-oxazolineshowed vasodilation and antihypertensive properties. Furthermore, a computational analysis of physicochemical parameters revealed that the most of the compounds possessed drug-like attributes. Using Bioinformatics approach, we found a correlation between the observed and predicted antimicrobial activities.


Assuntos
Antibacterianos/química , Antifúngicos/química , Oxazóis/química , Tiazóis/química , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Ésteres/química , Ésteres/farmacologia , Humanos , Absorção Intestinal , Klebsiella pneumoniae/efeitos dos fármacos , Simulação de Acoplamento Molecular , Oxazóis/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Streptococcus pyogenes/efeitos dos fármacos , Tiazóis/farmacologia
15.
Curr Drug Deliv ; 12(2): 210-22, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-22452407

RESUMO

Diabetes mellitus is a chronic disease accompanied by a multitude of problems worldwide with subcutaneously administered insulin being the most common therapy currently. Controlledrelease insulin is assumed to be of high importance for long-term glycaemic control by reducing the number of daily injections. Long-acting insulin also mimics the basal insulin levels in normal individuals that may be lacking in diabetic patients. Nanoparticles of carbonate apatite as established for efficient intracellular transport of DNA and siRNA have the potential to be used for sustained release of insulin as responsive nano-carriers. The flexibility in the synthesis of the particles over a wide range of pHs with eventual adjustment of pH-dependent particle dissolution and the manageable variability of particle-integrity by incorporating selective ions into the apatite structure are the promising features that could help in the development of sustained release formulations for insulin. In particular strontium-incorporated carbonate apatite particles were formulated and compared with those of unsubstituted apatite in the context of insulin binding and subsequent release kinetics in DMEM, simulated buffer and finally human blood over a period of 20 hours. Clearly, the former demonstated to have a stronger electrostatic affinity towards the acidic insulin molecules and facilitate to some extent sustained release of insulin by preventing the initial burst effect at physiological pH in comparison with the latter. Thus, our findings suggest that optimization of the carbonate apatite particle composition and structure would serve to design an ideal insulin nano-carrier with a controlled release profile.


Assuntos
Apatitas/química , Química Farmacêutica/métodos , Preparações de Ação Retardada/química , Insulina/sangue , Estrôncio/química , Preparações de Ação Retardada/síntese química , Liberação Controlada de Fármacos , Humanos , Nanopartículas/química
16.
Eur J Med Chem ; 70: 887-900, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24262381

RESUMO

Novel series of long chain isoxazole derivatives were designed as inhibitors of Cytochrome P450-14DM14a-demethylase from Candida albicans and ribosomal subunit of S12 protein from Escherichia coli. The novel compounds (6-10) were synthesized through 1,3-dipolar cycloaddition of nitrile oxide to long chain alkynoic acid and alkenyl/hydroxyalkenyl esters and tested for their antimicrobial activity by disk diffusion assay and MIC by broth micro dilution method. After predicting the hidden potential and drug-likeness of compounds, ADMET-related descriptors were also calculated to predict pharmacokinetic properties. Molecular docking studies have been performed to evaluate possible mode of action of molecules in active site of receptor. Compounds (9 and 10) showed excellent antimicrobial activity nearly equivalent to the control compounds.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Candida/efeitos dos fármacos , Ácidos Graxos/farmacologia , Compostos Heterocíclicos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Ciclização , Relação Dose-Resposta a Droga , Desenho de Fármacos , Ácidos Graxos/síntese química , Ácidos Graxos/química , Compostos Heterocíclicos/síntese química , Compostos Heterocíclicos/química , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Software , Relação Estrutura-Atividade
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