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1.
Discov Nano ; 19(1): 35, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38407670

RESUMO

Biomaterials play a vital role in targeting therapeutics. Over the years, several biomaterials have gained wide attention in the treatment and diagnosis of diseases. Scientists are trying to make more personalized treatments for different diseases, as well as discovering novel single agents that can be used for prognosis, medication administration, and keeping track of how a treatment works. Theranostics based on nano-biomaterials have higher sensitivity and specificity for disease management than conventional techniques. This review provides a concise overview of various biomaterials, including carbon-based materials like fullerenes, graphene, carbon nanotubes (CNTs), and carbon nanofibers, and their involvement in theranostics of different diseases. In addition, the involvement of imaging techniques for theranostics applications was overviewed. Theranostics is an emerging strategy that has great potential for enhancing the accuracy and efficacy of medicinal interventions. Despite the presence of obstacles such as disease heterogeneity, toxicity, reproducibility, uniformity, upscaling production, and regulatory hurdles, the field of medical research and development has great promise due to its ability to provide patients with personalised care, facilitate early identification, and enable focused treatment.

2.
J Biochem Mol Toxicol ; 38(1): e23627, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38229316

RESUMO

The given investigation examined the neuroprotection role of 5-HT1b/1d agonist in reserpine induced Parkinson's disease (PD) in male Wistar rats. PD was induced in rats by reserpine at 5 mg/kg ip for 3 days and thereafter the rats were provided with the following treatments for 4 days, zolmitriptan (ZLM) group (30 mg/kg ip); STD group (levodopa + carbidopa, 200 + 5 mg/kg ip); ZLM + GA group (zolmitriptan, 30 mg/kg ip and glutamic acid, 1.5 mg/kg); ZLM + DX group (zolmitriptan, 30 mg/kg ip and dextromethorphan, 20 mg/kg ip). All the groups were then assessed for cognitive and motor functions at the end of the protocol. Moreover, oxidative stress parameters and histopathological changes were observed in rats of all treatment groups. Deposition of α-synuclein in the brain tissue was observed by silver staining. Data of this investigation revealed that motor and cognitive functions were improved in the ZLM-treated group compared with the negative control group, which was observed to be reversed in ZLM + GA group. Treatment with ZLM ameliorated oxidative stress and histopathological changes in the brain tissue of PD rats. Further, ZLM reduced the deposition of α-synuclein in PD rats, which reversed in ZLM + GA-treated group. This study concludes by stating that 5-HT1b/1d agonist can prevent neurodegeneration and reduce oxidative stress in PD rats. The probable underlying mechanism of such an effect of 5-HT1b/1d agonist could be by regulating the deposition of α-synuclein and reducing the expression of NMDA receptor.


Assuntos
Oxazolidinonas , Doença de Parkinson , Agonistas do Receptor 5-HT1 de Serotonina , Triptaminas , Masculino , Ratos , Animais , Agonistas do Receptor 5-HT1 de Serotonina/farmacologia , Doença de Parkinson/tratamento farmacológico , alfa-Sinucleína , Ácido Glutâmico , Reserpina , Ratos Wistar
3.
Nutr Diabetes ; 13(1): 26, 2023 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-38052812

RESUMO

OBJECTIVES: Present report evaluates the protective effect of geraniol on high fat diet (HFD) induced obesity in rats and also determines the molecular mechanism of it. METHODS: Rats were induced with obesity with administration of HFD for four weeks and geraniol 200 and 400 mg/kg p.o. was administered for the next four week in the respective groups. Blood glucose and oral glucose tolerance test (OGTT), lipid profile was estimated in the geraniol treated HFD induced obesity in rats. Moreover, docking study was performed to determine the specific mechanism of geraniol by targeting HMG-CoE A reductase (in silico). RESULTS: There was significant increase in body weight and amelioration in altered serum glucose and lipid profile were observed in the geraniol treated group than negative control group. Weight of organs and adipose tissue isolated from different regions of the body was reduced in geraniol treated group than negative control. Moreover, geraniol interact with HMG-CoA reductase having binding energy -5.13. CONCLUSIONS: In conclusion, data of the report reveals that geraniol reduces obesity by promoting the conversion of white adipose tissue (WAT) to brown adipose tissue (BAT), as it interacts with HMG-CoA reductase in HFD induced obesity in rats.


Assuntos
Tecido Adiposo Marrom , Dieta Hiperlipídica , Ratos , Animais , Obesidade/metabolismo , Tecido Adiposo Branco/metabolismo , Lipídeos
4.
Langmuir ; 39(41): 14626-14637, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37797324

RESUMO

Solutions of macromolecules can undergo liquid-liquid phase separation to form droplets with ultralow surface tension. Droplets with such low surface tension wet and spread over common surfaces such as test tubes and microscope slides, complicating in vitro experiments. The development of a universal super-repellent surface for macromolecular droplets has remained elusive because their ultralow surface tension requires low surface energies. Furthermore, the nonwetting of droplets containing proteins poses additional challenges because the surface must remain inert to a wide range of chemistries presented by the various amino acid side chains at the droplet surface. Here, we present a method to coat microscope slides with a thin transparent hydrogel that exhibits complete dewetting (contact angles θ ≈ 180°) and minimal pinning of phase-separated droplets in aqueous solution. The hydrogel is based on a swollen matrix of chemically cross-linked polyethylene glycol diacrylate of molecular weight 12 kDa (PEGDA), and can be prepared with basic chemistry laboratory equipment. The PEGDA hydrogel is a powerful tool for in vitro studies of weak interactions, dynamics, and the internal organization of phase-separated droplets in aqueous solutions.

5.
Biosens Bioelectron ; 214: 114545, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35839595

RESUMO

This review article focusses on new advances in the field of enzyme fuel cells (EFCs), especially, on flexible materials which can be used to make flexible EFCs for wearable devices, three-dimensional (3D) printed structures to prepare electrodes for EFCs and micro/nano electromechanical structures (MEMS/NEMS) to fabricate micro-EFCs. Particular attention is given to newly developed approaches to obtain efficient electrodes for harvesting energy via EFCs. This review article explains the various attributes of these recently developing technologies and their ability to mitigate the energy requirements of flexible/wearable bioelectronic devices. Besides discussing key milestones achieved, this perspective review article also emphasizes the main hurdles that are currently impeding the realization of flexible/wearable EFCs. We have also emphasized on the major hurdles related to the flexible materials required to fabricate wearable EFCs, suitable 3D printing techniques required, and MEMS and NEMS to fabricate micro-EFCs. In all the recently developed techniques, there are some common issues like stability, low power output, mechanical strength and flexibility. This review article also provides various routes to mitigate these issues. The main aim of this perspective article is to develop curiosity among the researchers of various fields to team up in order to address the huge challenges that restrict the real-world application of flexible/wearable EFCs. Such collaboration is important to harness the full potential of EFCs. It is requested to read this review article with supporting information to get the complete essence.


Assuntos
Técnicas Biossensoriais , Dispositivos Eletrônicos Vestíveis , Técnicas Biossensoriais/métodos , Eletrodos , Impressão Tridimensional
6.
ACS Macro Lett ; 11(6): 813-817, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35674524

RESUMO

Heterotelechelic polymers are an important class of materials finding applications in bioconjugation, imaging, sensing, and synthesis of organic/inorganic hybrid systems with interesting features. However, the synthesis of such polymers is challenging. Here, we report a mechanistically unique and most efficient method based on a single functionalization agent to prepare heterotelechelic polymers by a ring-opening metathesis polymerization. Different functionalization agents can be synthesized in one simple step from inexpensive commercial starting materials. The functionalization agents initially generate a functional initiator from commercial Grubbs' first-generation ruthenium benzylidene catalyst. During this process, a functional dihydrofuran derivative is produced. After functional initiation and propagation of a suitable monomer, the dihydrofuran derivative functionally terminates the polymerization yielding a primary alcohol-terminated heterotelechelic polymer. Molecular weight control is achieved by varying the ratio between monomer and Grubbs' first-generation catalyst. This method may emerge as a popular choice to prepare heterotelechelic polymers due to its simplicity and efficiency.


Assuntos
Polímeros , Rutênio , Catálise , Peso Molecular , Polimerização
7.
Saudi J Anaesth ; 16(2): 172-175, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35431735

RESUMO

Background: Various scoring systems help in classifying the patient's risk preoperatively and hence to decide the best available treatment option. ACS-NSQIP score has been introduced in clinical practice for few years. This study was done to find out whether there is any difference between predicted mortality from ACS-NSQIP score and observed mortality in Saudi population. Methods: This prospective observational study was conducted at Security Forces Hospital, Riyadh, Kingdom of Saudi Arabia. We included patients undergoing elective and emergency surgical procedures in our hospital. Thirty days mortality data was collected and then observed to expected (O/E) mortality ratio was calculated. The sample size for our study was nine hundred and three (903) patients. Results: The mean ACS-NSQIP mortality risk score (%) for the study was 0.49. Expected number of mortalities was 4.42 while observed mortalities were 11, yielding an O/E ratio of 2.48 (p-value 0.000). We did not find a significant difference between expected and observed mortalities except for ASA class 3 and 4 patients where expected numbers of mortalities were lower than observed (p-value < 0.05). Conclusion: ACS-NSQIP can be reliably used for postoperative mortality prediction especially in lower risk groups.

8.
Microb Pathog ; 165: 105493, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35307600

RESUMO

Present investigation evaluates the protective effect of vanillin against sepsis. Sepsis was induced by cecal ligation and puncture (CLP) in rat and vanillin was administered at dose of 100 and 200 mg/kg p.o. for five days after induction of sepsis. Effect of vanillin was observed on the percentage of survival, body weight and food intake were determined in CLP induced sepsis rats. Level of liver enzymes in the serum and organ weight was also observed in vanillin treated CLP induced rats. Moreover, histopathological changes were also observed in liver and lung tissue of hematoxylin and eosin (H&E) staining. There was significant improvement in bodyweight and food intake in vanillin treated group than negative control group after the sepsis induction. Moreover, vanillin improves the percentage of survival rate and reduces the level of liver enzymes and spleen weight in CLP induced sepsis rat. It also improves the level of glutathione (GSH) compared to negative control group. In conclusion, data of investigation reveals that vanillin ameliorates the survival rate and oxidative stress in CLP induced sepsis rat model.


Assuntos
Ceco , Sepse , Animais , Benzaldeídos , Ceco/patologia , Modelos Animais de Doenças , Glutationa , Ligadura , Punções , Ratos , Sepse/tratamento farmacológico
9.
J Pak Med Assoc ; 72(12): 2491-2497, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37246675

RESUMO

OBJECTIVE: To assess the effect of intravenous ketamine on postoperative pain control, opioid consumption, and the incidence of postoperative adverse events in gynaecological surgeries. METHODS: The systematic review and meta-analysis were conducted in July 2020 and the search was repeated in July 2021 to ensure accuracy. The review was registered with the International Prospective Register of Systematic Reviews (PROSPERO) as ID-CRD42020188637 in July 2020. The search, done on online databases Medline and Science Direct, comprised studies on patients who underwent general anaesthesia for gynaecological surgeries and received intravenous ketamine intraoperatively, and the findings included opioid consumption, postoperative pain control, and associated side-effects. RESULTS: Of the 79 randomised controlled trials found, 9 (11.4%) were subjected to meta-analysis. The use of intravenous ketamine reduced pain score at 2h (p=0.003) and 24h (p=0.002) postoperatively in gynaecological surgeries. In laparoscopic gynaecological surgeries, lower pain scores were reported at 1h (p=0.01) and 2h (p=0.002) postoperatively. Lower pain scores were reported at 24h postoperatively in open gynaecological surgeries (p=0.002). Intravenous ketamine increased the time to first-request analgesia postoperatively (p=0.03), and reduced postoperative 24h opioid consumption (p=0.002). CONCLUSIONS: The use of intravenous ketamine significantly reduced postoperative pain at 2h and 24h after gynaecological surgeries and at 1h and 2h after laparoscopic gynaecological surgeries.


Assuntos
Ketamina , Humanos , Feminino , Ketamina/uso terapêutico , Analgésicos Opioides/uso terapêutico , Revisões Sistemáticas como Assunto , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle , Procedimentos Cirúrgicos em Ginecologia/efeitos adversos
10.
Mol Biol Res Commun ; 10(3): 131-140, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34476266

RESUMO

The severe acute respiratory syndrome is a viral respiratory disease recognised as COVID-19, caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Formerly, no precise remedies are available, and many studies regarding COVID-19 prevention and treatment are under development. Several targets for the design of drugs are identified, and studies are in headway to explore the potential target. RNA-dependent RNA polymerase (RdRp) protein identified as a promising target against SARS-CoV-2 infection for the drug design due to its significant role in viral replication. The present study focuses on identifying the binding effect of previously known RdRp inhibitors with RdRp of SARS-CoV-2 using molecular docking and molecular dynamics simulation approaches. Molecular docking and binding free energy calculations against RdRp enzyme identified suramin as a potential compound that showed the highest docking score of -7.83 Kcal/mole and binding energy of -80.83 Kcal/mole as a comparison to other compounds. Further, molecular dynamics simulation studies were moreover showed the stable binding behaviour of suramin docked complex in the protein active site. Thus, the study concludes that suramin might be helpful as a potential inhibitor against RNA-dependent RNA polymerase of SRAS-CoV-2. However, further investigation is needed to assess the possible effect of inhibitors on RdRp through in vitro and in vivo experiments.

11.
Small ; 17(44): e2103061, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34558188

RESUMO

Polymers are essential components of many nanostructured materials. However, the refractive indices of common polymers fall in a relatively narrow range between 1.4 and 1.6. Here, it is demonstrated that loading commercially-available polymers with large concentrations of a plant-based pigment can effectively enhance their refractive index. For polystyrene (PS) loaded with 67 w/w% ß-carotene (BC), a peak value of 2.2 near the absorption edge at 531 nm is achieved, while maintaining values above 1.75 across longer wavelengths of the visible spectrum. Despite high pigment loadings, this blend maintains the thermoforming ability of PS, and BC remains molecularly dispersed. Similar results are demonstrated for the plant-derived polymer ethyl cellulose (EC). Since the refractive index enhancement is intimately connected to the introduction of strong absorption, it is best suited to applications where light travels short distances through the material, such as reflectors and nanophotonic systems. Enhanced reflectance from films is experimentally demonstrated, as large as sevenfold for EC at selected wavelengths. Theoretical calculations highlight that this simple strategy can significantly increase light scattering by nanoparticles and enhance the performance of Bragg reflectors.


Assuntos
Nanopartículas , Nanoestruturas , Polímeros , Poliestirenos , Refratometria
12.
Environ Anal Health Toxicol ; 36(3): e2021020-0, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34428861

RESUMO

Methyl isocyanate (MIC), a low molecular weight synthetic aliphatic compound, having an isocyanate group (-NCO), has industrial application. In this study, the effects of methyl isocyanate and its mechanism on outer membrane protein of Escherichia coli were observed using experimental and computational methods. In vitro exposure of N-succinimidyl N-methylcarbamate (NSNM) a synthetic analogue of MIC on E. coli to a final concentration of 2 mM was found to affect the growth curve pattern and changes in cell morphology. Molecular docking studies of MIC and NSNM with E. coli outer membrane protein (OmpW, OmpX, OmpF OmpA), and periplasmic domain (PAL) were performed. The in-silico results revealed that outer membrane protein OmpF showed the highest negative binding energy, i.e. ∆G -4.11 kcal/mole and ∆G -3.19 kcal/mole by NSNM and MIC as compared to other proteins. Our study concludes that methyl isocyanate retains lethal toxicity which leads to cell death due to the membrane protein damage of E. coli membrane.

14.
ACS Macro Lett ; 10(2): 210-214, 2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35570788

RESUMO

Norbornene is polymerized extremely fast when reacted with Grubbs' first (G1) or third generation catalyst (G3) because of its very high ring strain energy. Cyclohexene, on the other hand, cannot be polymerized using G1 or G3 due to its very low ring strain energy. Subsequently, the sequence-selective polymerization of these two monomers is extremely challenging. A sequence-selective cascade ring-opening/ring-closing metathesis polymerization of the monomer M containing both the norbornene and the cyclohexene ring using G1 or G3 is reported. The polymer structure was analyzed by 1H NMR, 1H-1H COSY, and 1H-1H ROESY spectroscopy and MALDI-ToF mass spectrometry. Polymers with moderate molecular weight dispersities and good molecular weight control were achieved by varying the ratio between monomer M and G1.


Assuntos
Norbornanos , Polímeros , Cicloexenos , Peso Molecular , Norbornanos/química , Polimerização , Polímeros/química
16.
Toxicol Res (Camb) ; 9(5): 706-713, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33178431

RESUMO

Snakebite is considered as one of the acute severe medical problems across the world. Snake venoms composed of various group of toxins, enzymes and non-toxic enzymes. Phospholipases A2 present in Naja naja snake venom plays a significant role in lipid signalling and contributes to different inflammation in the human body. Dryopteris cochleata rhizomes have antioxidant, antimicrobial property and used to treat lesions, gonorrhoea, sores, muscular pain, rheumatic and also useful in dog and snake bites. In this study, Indian male fern D. cochleata rhizomes have been used for green synthesis of silver nanoparticles with the aim to increase the bioactivity of plant extract and to evaluate N. naja snake venom inhibition activity of prepared nanoparticles. Green synthesized nanoparticles were characterized with the help of ultraviolet-visible spectroscopy, Fourier-transform infrared spectroscopy, X-ray powder diffraction and atomic force microscopy. Naja naja venom inhibition activity of nanoparticles was performed using in vitro phospholipases A2 assay and tissue damage activity. The results showed that surface plasmon resonance maxima peaks of nanoparticles were observed at 424 nm. Average particle size was around 35 nm, with a spherical shape. Neutralization results exhibited that synthesized silver nanoparticles from D. cochleata decreased percentage of tissue damage, resulting in significant inhibition of phospholipase A2 and N. naja snake venom. Results concluded that green synthesized silver nanoparticles from D. cochleata rhizome neutralize N. naja snake venom activity.

17.
Plant Foods Hum Nutr ; 75(4): 458-466, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33037564

RESUMO

The severe acute respiratory syndrome is a viral respiratory infection and commonly called as COVID-19, caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). It widely transmitted through direct or indirect contact. Currently, no specific treatment against SARS-CoV-2 are available; only prevention and supportive strategy are the preventive measures. The present review emphasizes the latest research related to COVID-19 and SARS-CoV-2 virus as well as the current status of potential inhibitors identified. Recent interest in SARS-CoV-2 has focused on transmission, symptoms, structure, and its structural proteins that exhibit promising therapeutics targets for rapid identification of potential inhibitors. The quick identification of potential inhibitors and immune-boosting functional food ingredients are crucial to combat this pandemic disease. We also tried to give an overview of the functional food components as a nutritional supplement, which helps in boosting our immune system and could be useful in preventing the COVID-19 and/or to improve the outcome during therapy.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Alimento Funcional , Pandemias , Pneumonia Viral , COVID-19 , Humanos , SARS-CoV-2
18.
Angew Chem Int Ed Engl ; 59(32): 13597-13601, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32339396

RESUMO

Using a one-step synthetic route for block copolymers avoids the repeated addition of monomers to the polymerization mixture, which can easily lead to contamination and, therefore, to the unwanted termination of chain growth. For this purpose, monomers (M1-M5) with different steric hindrances and different propagation rates are explored. Copolymerization of M1 (propagating rapidly) with M2 (propagating slowly), M1 with M3 (propagating extremely slowly) and M4 (propagating rapidly) with M5 (propagating slowly) yielded diblock-like copolymers using Grubbs' first (G1) or third generation catalyst (G3). The monomer consumption was followed by 1 H NMR spectroscopy, which revealed vastly different reactivity ratios for M1 and M2. In the case of M1 and M3, we observed the highest difference in reactivity ratios (r1 =324 and r2 =0.003) ever reported for a copolymerization method. A triblock-like copolymer was also synthesized using G3 by first allowing the consumption of the mixture of M1 and M2 and then adding M1 again. In addition, in order to measure the fast reaction rates of the G3 catalyst with M1, we report a novel retardation technique based on an unusual reversible G3 Fischer-carbene to G3 benzylidene/alkylidene transformation.

19.
Angew Chem Int Ed Engl ; 58(43): 15278-15282, 2019 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-31456331

RESUMO

A recently developed catalytic living ring opening metathesis polymerisation (ROMP) was investigated using a series of reversible chain transfer agents (CTA) carrying either cyclopentene or cyclohexene rings, differing only in ring strain. All cyclopentene derivatives examined showed significantly faster reaction rates than the corresponding cyclohexene derivatives. This resulted in lower molecular weight dispersities and better control of the molecular weight for the cyclopentene compared to the cyclohexene CTAs. Both Grubbs' second and third generation catalysts could be employed in catalytic living ROMP using cyclopentene CTA derivatives. The kinetics of different CTAs were studied, block copolymers were synthesised and residual ruthenium quantified by ICP-OES. All polymers were fully characterised by NMR, GPC and MALDI-ToF mass spectrometry. The new cyclopentene CTAs are readily synthesised in a few straightforward steps and provide faster reaction kinetics than all previously reported reversible CTAs.

20.
Nat Chem ; 11(5): 488-494, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30962611

RESUMO

In a conventional living ring-opening metathesis polymerization (ROMP), an equal number of ruthenium complexes to the number of polymer chains synthesized are required. This can lead to high loadings of ruthenium complexes when aiming for shorter polymers. Here, a reversible chain-transfer agent was used to produce living ROMP polymers from norbornene derivatives using catalytic amounts of Grubbs' ruthenium complexes. The polymers obtained by this method showed all of the characteristics of a living polymerization (that is, good molecular weight control, narrow molecular weight dispersities and the ability to form block copolymers). Monomers carrying functional moieties such as ferrocene, coumarin or a triisopropylsilyl-protected primary alcohol could also be catalytically polymerized in a living fashion. The method presented follows a degenerative chain-transfer process and is more economical and environmentally friendly compared with previous living ROMP procedures as it utilizes only catalytic amounts of costly and toxic ruthenium complexes.

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