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1.
Curr Med Chem ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38847381

RESUMO

Cancer, a complicated and multi-dimensional medical concern worldwide, can be identified via either the growth of malignant tumours or colonisation of nearby tissues attributing to uncontrollable proliferation and division of cells promoted by several influential factors, including family history, exposure to pollutants, choice of lifestyle, and certain infections. The intricate processes underlying the development, expansion, and advancement of cancer are still being studied. However, there are a variety of therapeutic alternatives available for the diagnosis and treatment of cancer depending on the type and stage of cancer as well as the patient's individuality. The bioactive compoundsfortified nanofiber-based advanced therapies are revolutionary models for cancer detection and treatment, specifically targeting melanoma cells via exploring unique properties, such as increased surface area for payload, and imaging and bio-sensing capacities of nano-structured materials with minimal damage to functioning organs. The objective of the study was to gain knowledge regarding the potentiality of Nanofibers (NFs) fabricated using biomaterials in promoting cancer management along with providing a thorough overview of recent developmental initiatives, challenges, and future investigation strategies. Several fabrication approaches, such as electrospinning, self-assembly, phase separation, drawing, and centrifugal spinning of bio-compatible NFs along with characterization techniques, have been elaborated in the review.

2.
Pharm Nanotechnol ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38756071

RESUMO

BACKGROUND: Worldwide, cancer is the second most common cause of death. Chemotherapy and other traditional cancer treatments have toxicities that affect normal cells in addition to their intended targets, necessitating the development of novel approaches to enhance cell-specific targeting. METHODS: The present work summarizes the scientific information on nanoparticles in cancer theranostics to provide a comprehensive insight into the preventive and therapeutic potential of nanoparticles in cancer. Scopus, PubMed, Science Direct, and Google Scholar databases are searched to collect all the recent (2015-2023) scientific information on smart multifunctional nanoparticles using the terms nanotechnology, cancer theranostics, and polymer. RESULTS: The use of nanomaterials as chemical biology tools in cancer theranostics has been thoroughly investigated. They demonstrate expanded uses in terms of stability, biocompatibility, and enhanced cell permeability, enabling precision targeting and ameliorating the drawbacks of conventional cancer treatments. The nano platform presents a fascinating chance to acquire multifunctionality and targeting techniques. The production of smart nanomaterials, specifically with regard to the advent of nanotechnology, has revolutionized the diagnosis and treatment of cancer. The capability of nanoparticles to functionalize with a variety of biosubstrates, including aptamers, antibodies, DNA, and RNA, and their broad surface area allow them to encapsulate a huge number of molecules, contributing to their theranostic effect. Comparatively speaking, economical, easily produced, and less toxic nanomaterials formed from biological sources are thought to have benefits over those made using conventional processes. CONCLUSION: The present study highlights the uses of several nanoparticles (NPs), and describes numerous cancer theranostics methodologies. The benefits and difficulties preventing their adoption in cancer treatment and diagnostic applications are also critically reviewed. The use of smart nanomaterials, according to this review's findings, can considerably advance cancer theranostics and open up new avenues for tumor detection and treatment.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38482614

RESUMO

Globally, one of the leading causes of cancer-related deaths is colon cancer. As this form of cancer has a tremendous potential to metastasize, effective treatment is complicated and sometimes impossible. Despite the improvement of conventional chemotherapy and the advent of targeted therapies, overcoming multi-drug resistance (MDR) and side effects remain significant challenges. As a therapeutic intervention for targeted gene silencing in cancer, RNA technology shows promise and certain RNA-based formulations are currently undergoing clinical studies. Various studies have reported that RNA-based nanoparticles have demonstrated substantial promise for targeted medication delivery, gene therapy, and other biomedical applications. However, using RNA as a therapeutic tool presents severe limitations, mainly related to its low stability and poor cellular uptake. Nanotechnology offers a flexible and tailored alternative due to the difficulties in delivering naked RNA molecules safely in vivo, such as their short half-lives, low chemical stability, and susceptibility to nuclease degradation. In addition to shielding RNA molecules from immune system attacks and enzymatic breakdown, the nanoparticle-based delivery systems allow RNA accumulation at the tumor site. The potential of RNA and RNA-associated nanomedicines for the treatment of colon cancer, as well as the prospects for overcoming any difficulties related to mRNA, are reviewed in this study, along with the current progress of mRNA therapeutics and advancements in designing nanomaterials and delivery strategies.

4.
Curr Med Chem ; 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38375849

RESUMO

Cancer is defined as the unchecked expansion of aberrant cells. Radiation, chemotherapy, and surgery are currently used in combination to treat cancer. Traditional drug delivery techniques kill healthy proliferating cells when used over prolonged periods of time in cancer chemotherapy. Due to the fact that the majority of tumor cells do not infiltrate right away, this is particularly true when treating solid tumors. A targeted drug delivery system (TDDS) is a tool that distributes medication to a selected bioactive location in a controlled manner. Nanotechnology-based delivery techniques are having a substantial impact on cancer treatment, and polymers are essential for making nanoparticulate carriers for cancer therapy. The advantages of nanotherapeutic drug delivery systems (NDDS) in terms of technology include longer half-life, improved biodistribution, longer drug circulation time, regulated and sustained drug release, flexibility in drug administration method, higher drug intercellular concentration, and others. The benefits and drawbacks of cancer nanomedicines, such as polymer-drug conjugates, micelles, dendrimers, immunoconjugates, liposomes, and nanoparticles, are discussed in this work, along with the most recent findings on polymer-based anticancer drugs.

5.
Gels ; 9(4)2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37102943

RESUMO

In the 21st century, melanoma and non-melanoma skin cancers have become an epidemic outbreak worldwide. Therefore, the exploration of all potential preventative and therapeutic measures based on either physical or bio-chemical mechanisms is essential via understanding precise pathophysiological pathways (Mitogen-activated protein kinase, Phosphatidylinositol 3-kinase Pathway, and Notch signaling pathway) and other aspects of such skin malignancies. Nano-gel, a three-dimensional polymeric cross-linked porous hydrogel having a diameter of 20-200 nm, possesses dual properties of both hydrogel and nanoparticle. The capacity of high drug entrapment efficiency with greater thermodynamic stability, remarkable solubilization potential, and swelling behavior of nano-gel becomes a promising candidate as a targeted drug delivery system in the treatment of skin cancer. Nano-gel can be either synthetically or architectonically modified for responding to either internal or external stimuli, including radiation, ultrasound, enzyme, magnetic, pH, temperature, and oxidation-reduction to achieve controlled release of pharmaceuticals and several bio-active molecules such as proteins, peptides, genes via amplifying drug aggregation in the active targeted tissue and reducing adverse pharmacological effects. Several drugs, such as anti-neoplastic biomolecules having short biological half-lives and prompt enzyme degradability capacity, must be appropriate for administration employing either chemically bridged or physically constructed nano-gel frameworks. The comprehensive review summarizes the advancement in the preparation and characterization methods of targeted nano-gel with enhanced pharmacological potential and preserved intracellular safety limits for the mitigation of skin malignancies with a special emphasize on skin cancer inducing pathophysiological pathways and prospective research opportunities for skin malignancy targeted nano-gels.

6.
Turk J Pharm Sci ; 19(3): 251-266, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35775238

RESUMO

Objectives: The focus of this study was to design and optimize methylphenidate hydrochloride mouth dissolving film (MDF) that can be beneficial in an acute condition of attention deficit hyperactivity disorder (ADHD) and narcolepsy. Materials and Methods: Solvent casting method was used for the preparation of this film. Optimization of the effect of independent variables such as the number of polymers and active pharmaceutical ingredients [hydroxypropyl methyl cellulose (HPMC) E5, HPMC E15, and maltodextrin], % of drug release, disintegration time, and tensile strength of the film done using simplex centroid design. Complex formation of the film was tested using fourier-transform infrared spectroscopy and differential scanning calorimetry study. The multiple regression analysis was obtained from equations of the results that adequately describe influence of the independent variables on the selected responses. Polynomial regression analysis, contour plots, and 3-D surface plots were used to relate dependent and independent variables. Results: Experimental results indicated that different polymer amounts had complex effects on % drug release from the film, disintegration time as well as the tensile strength of the film. The observed responses were in near alignment with expected values calculated from the developed regression equations as shown by percentage relative error. Final formulation showed more than 95% drug release within 2 min and was shown to disintegrate within a minute that had good tensile strength. Conclusion: These findings suggest that MDF containing methylphenidate hydrochloride is likely to become a choice of methylphenidate hydrochloride preparations for treatment in ADHD and narcolepsy conditions.

7.
Materials (Basel) ; 15(8)2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35454419

RESUMO

Short-time, abrupt events-such as earthquakes and other shock loadings-often lead to damage that is difficult to detect in structures using output-only vibration measurements. The time-variant transmissibility is proposed to tackle this problem. The approach is based on two-dimensional wavelet power spectra. The time-frequency transmissibility and relevant coherence function are used for structural damage detection in structural elements in buildings. Numerical simulations and experimental tests are used in these investigations. The results are compared with the classical transmissibility and time-variant input-output wavelet approach. The paper shows that output-only measurements and wavelet-based transmissibility can be used to monitor abrupt damage-related changes to structural dynamics.

8.
Z Angew Math Phys ; 72(4): 155, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34720236

RESUMO

We are concerned here with an analysis of the nonlinear irrotational gravity water wave problem with a free surface over a water flow bounded below by a flat bed. We employ a new formulation involving an expression (called flow force) which contains pressure terms, thus having the potential to handle intricate surface dynamic boundary conditions. The proposed formulation neither requires the graph assumption of the free surface nor does require the absence of stagnation points. By way of this alternative approach we prove the existence of a local curve of solutions to the water wave problem with fixed flow force and more relaxed assumptions.

9.
Biotechnol Biofuels ; 12: 185, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31360222

RESUMO

BACKGROUND: Efforts to develop efficient lignocellulose-degrading enzymatic preparations have led to the relatively recent discovery of a new class of novel cellulase boosters, termed lytic polysaccharide monoxygenases (LPMOs). These enzymes are copper-dependent metalloenzymes that initiate the biomass deconstruction process and subsequently work together with cellulases, hemicellulases, and other accessory enzymes to enhance their hydrolytic action. Given their wide distribution and diversity, screening and isolation of potent LPMOs from natural fungal diversity may provide an important avenue for increasing the efficiency of cellulases and thereby decreasing cellulosic ethanol production costs. However, methods for quick screening and detection are still not widely available. In this article, a simple and sensitive method is described by combining nonhydrolytic activity enhancement followed by LC-MS-based quantitation of LPMOs. RESULTS: In this study, a screening approach has been developed for the detection of nonhydrolytic cellulase-enhancing enzymes in crude fungal supernatants. With the application of a saturating benchmark cocktail of Celluclast 1.5L, fungal isolates were selected which had the capability of hydrolyzing pretreated rice straw by their synergistic enzyme fractions. Subsequently, these fungal extracts along with an LPMO-enriched commercial enzyme were investigated for their ability to produce Type I LPMO activity. An LC-MS-based methodology was applied to quantitate gluconic acid in enzymatic hydrolysates as an indirect measurement of Type I LPMO activity. CONCLUSION: The present study describes an LC-MS-based separation method to detect and quantitate LPMO activity in a commercial enzyme. This method was also applied to screen fungal extracts. The developed screening strategy has enabled detection of LPMO activity in two industrially important Penicillium strains.

10.
Philos Trans A Math Phys Eng Sci ; 376(2111)2018 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-29229787

RESUMO

Bounds on estimates of wave heights (valid for large amplitudes) from pressure and flow measurements at an arbitrary intermediate depth have been provided. Two-dimensional irrotational steady water waves over a flat bed with a finite depth in the presence of underlying uniform currents have been considered in the analysis. Five different upper bounds based on a combination of pressure and velocity field measurements have been derived, though there is only one available lower bound on the wave height in the case of the speed of current greater than or less than the wave speed.This article is part of the theme issue 'Nonlinear water waves'.

11.
Bioresour Technol ; 224: 411-418, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27847236

RESUMO

In this study, commercial surfactants have been investigated at economically viable dosage to enhance the enzymatic saccharification of pretreated wheat straw at high solid loadings. Twenty one surfactants were evaluated with pilot scale pretreated wheat straw and mechanism of surfactant action has been elucidated. One surfactant has improved the saccharification of dilute acid wheat straw (DAWS) by 26.4% after 24h and 23.1% after 48h while, steam exploded wheat straw (SEWS) saccharification was increased by 51.2% after 24h and 36.4% after 48h at 10% solid loading. At 20% solid loading, about 31% increase in yield was obtained on DAWS and about 55% on SEWS after 48h. Further, lignin was isolated from pretreated wheat straws and characterized which revealed that SEWS derived lignin was more hydrophobic than DAWS lignin. This investigation suggests that surfactant supplementation during saccharification is an effective strategy to achieve higher saccharification yield.


Assuntos
Metabolismo dos Carboidratos/efeitos dos fármacos , Celulase/metabolismo , Lignina/metabolismo , Tensoativos/farmacologia , Triticum/química , Resíduos , Adsorção , Biomassa , Reatores Biológicos , Estabilidade Enzimática/efeitos dos fármacos , Fermentação/efeitos dos fármacos , Projetos Piloto , Espectroscopia de Prótons por Ressonância Magnética , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor , Especificidade por Substrato/efeitos dos fármacos , Ácidos Sulfúricos/farmacologia
12.
Bioresour Technol ; 218: 934-43, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27450124

RESUMO

The aim of the present work was to develop a mathematical model to describe the biomass and (total) lipid productivity of Chlorella pyrenoidosa NCIM 2738 under heterotrophic conditions. Biomass growth rate was predicted by Droop's cell quota model, while changes observed in cell quota (utilization) under carbon excess conditions were used for the modeling and predicting the lipid accumulation rate. The model was simulated under non-limiting (excess) carbon and limiting nitrate concentration and validated with experimental data for the culture grown in batch (flask) mode under different nitrate concentrations. The present model incorporated two modes (growth and stressed) for the prediction of endogenous lipid synthesis/induction and aimed to predict the effect and response of the microalgae under nutrient starvation (stressed) conditions. MATLAB and Genetic Algorithm were employed for the prediction and validation of the model parameters.


Assuntos
Biomassa , Chlorella/crescimento & desenvolvimento , Modelos Teóricos , Processos Heterotróficos , Cinética , Gotículas Lipídicas/química , Microalgas/crescimento & desenvolvimento
13.
Philos Trans A Math Phys Eng Sci ; 373(2035)2015 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-25583867

RESUMO

The paper discusses some of the recent developments in vibration control strategies for wind turbines, and in this context proposes a new dual control strategy based on the combination and modification of two recently proposed control schemes. Emerging trends in the vibration control of both onshore and offshore wind turbines are presented. Passive, active and semi-active structural vibration control algorithms have been reviewed. Of the existing controllers, two control schemes, active pitch control and active tendon control, have been discussed in detail. The proposed new control scheme is a merger of active tendon control with passive pitch control, and is designed using a Pareto-optimal problem formulation. This combination of controllers is the cornerstone of a dual strategy with the feature of decoupling vibration control from optimal power control as one of its main advantages, in addition to reducing the burden on the pitch demand. This dual control strategy will bring in major benefits to the design of modern wind turbines and is expected to play a significant role in the advancement of offshore wind turbine technologies.

14.
Int J Pharm Investig ; 1(3): 135-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23071935

RESUMO

In the present study we investigated the effect of polyamidoamine (PAMAM) dendrimers on the aqueous solubility of aceclofenac. The aqueous solubility of aceclofenac was measured in the presence of dendrimers in distilled water. The effect of variables, such as pH condition, concentration, temperature and generation (molecule size) of dendrimer, has been investigated. Results showed that the solubility of aceclofenac in the dendrimer solutions was proportional to dendrimer concentration. The order in which the dendrimers increased the solubility at a constant pH condition was G3 > G0. The influence of dendrimer solution pH on the solubility enhancement of aceclofenac suggests that it involves an electrostatic interaction between the carboxyl group of the aceclofenac molecule and the amine groups of the dendrimer molecule. The solubility of aceclofenac was inversely proportional to the temperature of dendrimer solution.Different generation (G0 and G3) PAMAM dendrimers have the potential to significantly enhance the solubility of poor water-soluble drugs.

15.
Int J Pharm Investig ; 1(4): 200-6, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23071944

RESUMO

Parenteral administration of pharmaceutical products is one of the most popular methods used to produce quick onset of action and also 100% bioavailability. Main problem occurs with the parenteral drug delivery is lack of convenience, affordability, accuracy, sterility, safety etc. Such drawbacks with this delivery system makes it less preferable. Hence, all the disadvantages of these systems can be easily overcome by use of prefilled syringes. The objective of this review article is to provide information regarding prefilled syringes; it's method of preparation, direction to use, advantages, its future scope, and development.

16.
J Adv Pharm Technol Res ; 2(4): 266-73, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22247895

RESUMO

The aim of this investigation was to develop fast dissolving tablet of cinnarizine. A combination of super disintegrants, i.e., sodium starch glycolate (SSG) and crosscarmellose sodium (CCS) were used along with camphor as a subliming material. An optimized concentration of camphor was added to aid the porosity of the tablet. A 3(2) full factorial design was applied to investigate the combined effect of two formulation variables: Amount of SSG and CCS. Infrared (IR) spectroscopy was performed to identify the physicochemical interaction between drug and polymer. IR spectroscopy showed that there is no interaction of drug with polymer. In the present study, direct compression was used to prepare the tablets. The powder mixtures were compressed into tablet using flat face multi punch tablet machine. Camphor was sublimed from the tablet by exposing the tablet to vacuum drier at 60°C for 12 hours. All the formulations were evaluated for their characteristics such as average weight, hardness, wetting time, friability, content uniformity, dispersion time (DT), and dissolution rate. An optimized tablet formulation (F 9) was found to have good hardness of 3.30 ± 0.10 kg/cm(2), wetting time of 42.33 ± 4.04 seconds, DT of 34.67 ± 1.53 seconds, and cumulative drug release of not less than 99% in 16 minutes.

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