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1.
ACS Appl Mater Interfaces ; 16(32): 42049-42058, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39092793

RESUMO

Carbon black slurry electrodes are an effective means to improve flow battery performance by increasing the active surface area necessary for electrochemical reactions with a cost-effective material. Current challenges with this specific flow battery chemistry include the stability and flowability of the carbon black suspensions, especially in response to formulation choices. Advancing the manufacturing, operation, and performance of these redox flow batteries requires a deeper understanding of how slurry formulation impacts its rheological profile and ultimately battery performance. In response to this need, the linear and nonlinear rheological responses of activated carbon (AC) based slurry electrode materials used in an all-iron flow battery in the presence of a nonionic surfactant (Triton X-100) were measured. Results from these measurements show the slurry is a colloidal gel with elasticity remaining constant despite increasing surfactant concentration until α (= Csurf/CAC) < 0.65. However, at α ≥ 0.65, the slurry abruptly transitions to a fluid with no measurable yield stress. This critical surfactant concentration at which the rheological profile undergoes a dynamic change matches the concentration found previously for gel collapse of this system. Moreover, this transition is accompanied by a complete loss of electrical conductivity. From these data we conclude the site specific adsorption of surfactant molecules often used in slurry formulation has a significant and dramatic impact on the stability and flowability of these suspensions. Work presented herein demonstrates the importance of additive choices when formulating a slurry electrode.

2.
Cells ; 13(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38474373

RESUMO

The mechanistic target of rapamycin (mTOR) is a serine/threonine kinase that functions via its discrete binding partners to form two multiprotein complexes, mTOR complex 1 and 2 (mTORC1 and mTORC2). Rapamycin-sensitive mTORC1, which regulates protein synthesis and cell growth, is tightly controlled by PI3K/Akt and is nutrient-/growth factor-sensitive. In the brain, mTORC1 is also sensitive to neurotransmitter signaling. mTORC2, which is modulated by growth factor signaling, is associated with ribosomes and is insensitive to rapamycin. mTOR regulates stem cell and cancer stem cell characteristics. Aberrant Akt/mTOR activation is involved in multistep tumorigenesis in a variety of cancers, thereby suggesting that the inhibition of mTOR may have therapeutic potential. Rapamycin and its analogues, known as rapalogues, suppress mTOR activity through an allosteric mechanism that only suppresses mTORC1, albeit incompletely. ATP-catalytic binding site inhibitors are designed to inhibit both complexes. This review describes the regulation of mTOR and the targeting of its complexes in the treatment of cancers, such as glioblastoma, and their stem cells.


Assuntos
Glioblastoma , Células-Tronco Neoplásicas , Sirolimo , Humanos , Glioblastoma/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Células-Tronco Neoplásicas/metabolismo
3.
Int J Biol Macromol ; 250: 126169, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37558023

RESUMO

The present study aims to establish an integrated strategy for valorization of kinnow peel waste. A total of ten natural deep eutectic solvents (NADESs) were exploited for extraction of pectin. The highest yield of pectin enriched material was reported 35.66 % w/dw using choline chloride-Maltose based NADES. The extraction process parameters and chemical composition of NADES influenced the yield and different associated physico-chemical attributes of the pectin enriched material. All the recovered pectin enriched materials found to be composed of low methoxy pectin (degree of methylation: 18.41-40.26 %) and galacturonic acid (GalA) content was in range of 67.56-78.22 %. The Principal Component Analysis (PCA) was used to categorise isolated pectin enriched materials based on similarities and differences. The liquid fraction upon pectin extraction presented a considerable amount of fermentable sugar which was further utilized for lactic acid production by microbial intervention. The microbial strain Lactobacillus amylophilus GV6 was exploited for lactic acid fermentation where the highest yield reached 55.59 g/L. A sustainable and straight-forward biorefinery concept was developed for extraction of pectin enriched material and lactic acid production from kinnow peel waste with potential application in food and biotechnological sectors.

4.
Adv Biol Regul ; 88: 100946, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36658088

RESUMO

The mechanistic target of rapamycin (mTOR), a serine/threonine kinase, functions by forming two multiprotein complexes termed mTORC1 and mTORC2. Glioblastoma (GBM) is a uniformly fatal brain tumor that remains incurable partly due to the existence of untreatable cancer stem cells (CSC). The pathogenesis of GBM is largely due to the loss of the tumor suppressor gene PTEN, which is implicated in the aberrant activation of the mTOR pathway. The major cause of tumor recurrence, growth, and invasion is the presence of the unique population of CSC. Resistance to conventional therapies appears to be caused by both extensive genetic abnormalities and dysregulation of the transcription landscape. Consequently, CSCs have emerged as targets of interest in new treatment paradigms. Evidence suggests that inhibition of the mTOR pathway can also be applied to target CSCs. Here we explored the role of the mTOR pathway in the regulation of stem cells of GBM by treating them with inhibitors of canonical PI3K/AKT/mTOR pathways such as rapamycin (mTORC1 inhibitor), PP242 (ATP binding mTORC1/2 inhibitor), LY294002 (PI3K inhibitor), and MAPK inhibitor, U0126. A significant number of GBM tumors expressed stem cell marker nestin and activated mTOR (pmTORSer2448), with most tumor cells co-expressing both markers. The expression of stem cell marker NANOG was suppressed following rapamycin treatment. The neurospheres were disrupted following rapamycin and LY294002 treatments. Rapamycin or PP242 along with differentiating agent All-trans-retinoic acid reduced stem cell proliferation. Treatment with novel small molecule inhibitors of mTORC1/2 demonstrated that Torin1 and Torin2 suppressed the proliferation of GBM CSC, while XL388 was less effective. Torin1 and XL388 delay the process of self-renewal as compared to controls, whereas Torin2 halted self-renewal. Torin2 was able to eradicate tumor cells. In conclusion, Torin2 effectively targeted CSCs of GBM by halting self-renewal and inhibiting cell proliferation, underscoring the use of Torin2 in the treatment of GBM.


Assuntos
Glioblastoma , Sirolimo , Humanos , Sirolimo/farmacologia , Transdução de Sinais , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proliferação de Células , Células-Tronco/metabolismo , Linhagem Celular Tumoral
5.
J Colloid Interface Sci ; 633: 712-722, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36481426

RESUMO

HYPOTHESIS: Carbon black particles act as electronically conductive additives in the slurry electrodes used in electrochemical redox flow batteries. Modifying the carbon black slurry formulation with the addition of a nonionic surfactant could impart improved particle dispersion, gravitational stability, and flowability leading to better battery performance. EXPERIMENTS: Carbon black particles were dispersed in 1 M H2SO4 with volume fractions Φ = 0.01 to 0.06 and a nonionic surfactant (Triton X-100) concentration of csurf. = 0, 0.05, and 0.1 M. Particle size was characterized using microscopy and surfactant adsorption using UV-vis spectroscopy. Sedimentation kinetics was measured using a custom camera set-up that tracks the height of the settling particle bed. Rheology experiments were conducted to measure linear viscoelasticity and shear flow behavior. FINDINGS: The sedimentation dynamics of the slurry resembled that of a gel collapse. At short times we observed fast sedimentation associated with structural gel collapse and at long times very slow sedimentation associated with compaction of the sediment. Rheological investigations revealed that the slurry indeed behaved like colloidal gels. Addition of nonionic surfactant at α (= (csurf./cCB)) < 0.75 improved particle dispersion and increased gel elasticity. However, α> 0.75 led to a weaker gel that exhibits a fast 'catastrophic collapse' under gravity.

6.
J Chem Phys ; 157(23): 234902, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36550059

RESUMO

Shear history plays an important role in determining the linear and nonlinear rheological response of colloidal gels and can be used for tuning their structure and flow properties. Increasing the colloidal particle aspect ratio lowers the critical volume fraction for gelation due to an increase in the particle excluded volume. Using a combination of rheology and confocal microscopy, we investigate the effect of steady and oscillatory preshear history on the structure and rheology of colloidal gels formed by silica spheres and rods of length L and diameter D (L/D = 10) dispersed in 11 M CsCl solution. We use a non-dimensional Mason number, Mn (=Fvisc./Fattr.), to compare the effect of steady and oscillatory preshear on gel viscoelasticity. We show that after preshearing at intermediate Mn, attractive sphere gel exhibits strengthening, whereas attractive rod gel exhibits weakening. Rheo-imaging of gels of attractive rods shows that at intermediate Mn, oscillatory preshear induces large compact rod clusters in the gel microstructure, compared to steady preshear. Our study highlights the impact of particle shape on gel structuring under flow and viscoelasticity after shear cessation.

7.
Int J Biol Macromol ; 222(Pt B): 1918-1924, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36206841

RESUMO

With the advent of modern technology, the utilization of residues obtained after food processing are being largely explored for commercialization. Semolina, a starch rich food ingredient is one of such byproducts of food processing that has not been yet vividly studied, although it is profusely used as an important ingredient in Indian cuisines. Rapid digestibility of most starch rich foods boosts up the blood glucose level. Thus, the present study put forward an attempt to curtail the rapid digestibility of starch rich semolina flour by increasing its resistant starch content through enzymatic process. The enzymatically modified semolina flour (MS) was compared with its native counterpart (NS) on grounds of their digestibility pattern, biochemical and functional properties. A rise in resistant starch content by 9.3 ± 1.6 %, amylose content by 10.9 ± 1.2 %, crystallinity by 10.4 % and the drop in readily digestible starch by 11.9 ± 1.4 % and oil absorption by 2.1 ± 0.3 g/g were observed in MS. These initial findings of the present study are interesting as the results showed elevated potential of the modified semolina flour to be used as functional ingredient in cuisines worldwide.


Assuntos
Farinha , Amido Resistente , Farinha/análise , Amido/química , Triticum/química , Amilose , Grão Comestível
8.
Langmuir ; 38(45): 13674-13685, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36263911

RESUMO

Temperature-sensitive rod-like colloidal particles were synthesized by grafting a temperature-responsive polymer, poly(2-(dimethylamino)ethyl methacrylate) (PDMA), on the surface of high aspect ratio silica rods by surface-initiated atom transfer radical polymerization. The stability of the grafted polymer on the surface of the particles in aqueous solutions was found to deteriorate with time, leading to a gradual decrease of the polymer content of the hybrid colloids, which was attributed to the mechanically activated hydrolysis of the labile bonds at the polymer-silica interface. The polymer degrafting was significantly suppressed by first growing a hydrophobic poly(methyl methacrylate) block onto the particle surface to act as a barrier layer for the penetration of water molecules at the polymer-particle interface, followed by chain-extension with the hydrophilic PDMA chains. Dynamic light scattering, microscopy, and rheological measurements revealed that the PDMA block conferred a temperature-responsive behavior to the rod-like particles, which formed aggregates at temperatures above the lower critical solution temperature (LCST) of the polymer. However, in contrast to their spherical counterparts, the polymer-grafted rod-like particles did not exhibit complete thermo-reversibility upon lowering the solution temperature below the LCST of PDMA, which was reflected by different values of the diffusion coefficient for the heating and cooling cycles, indicating an irreversible rod particle aggregation upon increasing the temperature.

9.
Int J Biol Macromol ; 223(Pt B): 1674-1683, 2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36302485

RESUMO

The effect of amylopullulanase treatment on recrystallization behaviour and the formation of resistant starch crystals have been investigated. Extracted potato starch (Solanum tuberosum) has been subjected to the enzymatic assisted bioprocessing without any physical or chemical treatment, where 120 min of incubation, 7 % (v/v) of enzyme and 8 mL/g of water content were found to be optimum to increase the resistant starch content by 41.88 %. The resistant starch crystals showed the characteristic behaviour of B-type allomorph with an increase in 21.32 % crystallinity. The modified crystals portrayed less reduction in actual weight when assessed by thermo-gravimetric analysis. The compact linear arrangement of the linear amylose chains within the crystallized granule of starch has been evidenced by Bright Field Microscopy. The microstructure of the resistant starch crystals showed 33.18 % reduction in porosity when the 3-dimensional structural form was analysed by X-ray micro-Computed Tomography.


Assuntos
Amilopectina , Solanum tuberosum , Amilopectina/química , Solanum tuberosum/química , Amido Resistente , Microtomografia por Raio-X , Imageamento Tridimensional , Difração de Raios X , Amilose/química , Amido/química
10.
Soft Matter ; 17(5): 1232-1245, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33300930

RESUMO

A combination of rheology, optical microscopy and computer simulations was used to investigate the microstructural changes of a semi-dilute suspension of attractive rigid rods in an imposed shear flow. The aim is to understand the relation of the microstructure with the viscoelastic response, and the yielding and flow behaviour in different shear regimes of gels built from rodlike colloids. A semi-dilute suspension of micron sized, rodlike silica particles suspended in 11 M CsCl salt solution was used as a model system for attractive rods' gel. Upon application of steady shear the gel microstructure rearranges in different states and exhibits flow instabilities depending on shear rate, attraction strength, volume fraction and geometrical confinement. At low rod volume fractions, the suspension forms large, vorticity aligned, particle rich flocs that roll in the flow-vorticity plane, an effect that is due to an interplay between hydrodynamic interactions and geometrical confinement as suggested by computer simulations. Experimental data allow the creation of a state diagram, as a function of volume fraction and shear rates, identifying regimes of stable (or unstable) floc formation and of homogeneous gel or broken clusters. The transition is related to dimensionless Mason number, defined as the ratio of shear forces to interparticle attractive force.

11.
Neurol India ; 68(6): 1400-1408, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33342876

RESUMO

BACKGROUND: Nearly one-third of patients don't achieve seizure control with existing antiepileptic drugs. Brivaracetam (BRV) is a new member of the racetam class of drug, designed to selectively target SV2A, with binding affinity 15- to 30-fold greater than that of levetiracetam. OBJECTIVE: This pooled analysis reports efficacy and tolerability data of adjunct BRV (50, 100, and 200 mg/day) compared with placebo in Indian patients with uncontrolled focal epilepsy. METHODS: Data of 104 patients (aged 16-80 years) from 2 studies (N01252 and N01358) were pooled for this analysis. The studies comprised an 8-week prospective baseline period, and a 12-week treatment period. The study endpoints included median percent reduction from baseline in focal seizure frequency/28-days, ≥50% responder rate, and seizure freedom (all seizure types). The safety analysis included treatment-emergent adverse events (TEAEs). RESULTS: The efficacy population comprised 101 patients. In the Indian sub-group population, median percent reduction from baseline in focal seizure frequency/28-days was greater in the BRV dose groups: 39.7% (p = 0.00868), 46.8% (p = 0.00180) and 48.2% (p = 0.05224), for BRV 50, 100, 200 mg/day, respectively, compared with 20.6% for placebo. Responder rates (≥50%) were 38.1%, 45.7%, and 45.5% for BRV 50, 100, and 200 mg/day, respectively, compared with 11.7% for placebo. Complete seizure freedom was reported by 4.8% (1/21) and 2.9% (1/35) of patients on BRV50 and 100 mg/day, respectively, and none out of the 11 and 34 patients on BRV200 mg/day and placebo, respectively. In the safety population (n = 104), most commonly reported TEAEs (reported by ≥5% of patients taking brivaracetam) were headache and cough; most TEAEs were mild or moderate in intensity. CONCLUSION: This pooled analysis has provided evidence that adjunct brivaracetam, was effective and well-tolerated in Indian patients with uncontrolled focal epilepsy.


Assuntos
Epilepsias Parciais , Preparações Farmacêuticas , Anticonvulsivantes/uso terapêutico , Quimioterapia Combinada , Epilepsias Parciais/tratamento farmacológico , Humanos , Estudos Prospectivos , Pirrolidinonas , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
12.
Carbohydr Polym ; 237: 116158, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32241435

RESUMO

Starch rich foods are almost indispensable in mundane diet of people round the globe. Rapid digestibility of starch culminates into elevated blood glucose level which is an evident factor for many diseases. To curb this rapid digestibility and the elevated glycemic response, resistant starch content in highly nutritious but unexplored popped makhana (Euryale ferox) was increased by amylopullulanase treatment. In the present study, amylopullulanase treated makhana flour (MM) was compared with the native makhana flour (NM) based on physicochemical and functional properties, where enhanced amylose content, resistant starch and crystallinity were recorded to be 12.33 %, 14.88 % and 11.32 % respectively, whereas, readily digestible starch and oil holding capacity decreased by 13.01 % and 3.12 g/g respectively. The present study ensures the reduction and sustainable release of glucose during in vitro digestibility analysis. These findings point out the elevated potential of amylopullulanase treated makhana flour for therapeutic food formulation.


Assuntos
Farinha , Glicosídeo Hidrolases/química , Nozes , Nymphaeaceae , Amido/química , Amilases/química , Antioxidantes/química , Compostos de Bifenilo/química , Alimento Funcional , Glucana 1,4-alfa-Glucosidase/química , Picratos/química
13.
Recent Pat Biotechnol ; 10(1): 43-57, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27456821

RESUMO

BACKGROUND: Food-based technologies established itself as a vast, inter-disciplinary and multifaceted research area are at crossroads of scientific and technological advancements. The review of patents reveals that growing concerns over the source of nourishment for the burgeoning population, its quality, quantity and safety, along with associated human and environmental welfare has inspired global researchers to implement several new bio-based technologies. OBJECTIVE: Biotechnological interventions in food sector have been aimed at enhancing/modifying taste, aroma, shelf-life, texture and nutritional value of food products employing fermentation, enzyme technology, nanotechnology and molecular biology. The use of whole microbes as a source of nutrition and genetically modified microorganisms to be used as food or genetically modified food have been successfully attempted, which has addressed the mass population and malnutrition. Further, the processing techniques have been improved along with the proper utilization of food wastes for the generation of many useful byproducts. CONCLUSION: The article covers broadly the impact of biotechnological interventions in food sector. Techniques mostly discussed include not only the nutrient enriched food production but also byproduct utilization through proper improvisation of food waste into bioenergy, biomanure and other value added products, which is of great economic and environmental importance. This article reviews the overall aspects in relation to some of the recent advancements in food sector.


Assuntos
Biotecnologia/métodos , Tecnologia de Alimentos/métodos , Valor Nutritivo/fisiologia , Ásia , Fermentação/fisiologia , Humanos , Nanotecnologia/métodos , Patentes como Assunto
14.
J Clin Diagn Res ; 10(4): PD06-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27190883

RESUMO

Causes of urinary retention in old men include benign prostatic hyperplasia, prostatitis, prostate cancer, Scarring of the urethra or bladder neck as a result of injury or surgery, use of certain medicines particularly NSAIDs and opioid analgesics, constipation and neurogenic bladder. When the above common causes are not quite obvious by clinical examination and relevant investigations, then it is necessary to think of other rare diseases. It is with the above in our mind that a case of bladder outflow obstruction due to a large primary retrovesical hydatid cyst is herein reported in a 58-year-old man. Ultrasonography (USG) and Contrast Enhanced Computed Tomography (CECT) scan of the abdomen and pelvis of the patient revealed a large, multilocular, nonenhancing, cystic lesion in the rectovesical pouch having typical cartwheel appearance without any other intraabdominal organ involvement. These typical radiological characteristics led us to suspect the presence of a hydatid cyst. He underwent exploratory laparotomy where cystopericycstectomy was done. Pre-operative and post-operative albendazole prophylaxis was also given. In conclusion, hydatid cyst should always be considered in the differential diagnosis of pelvic cystic masses, specially in endemic regions.

16.
Ren Fail ; 35(8): 1173-5, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23879675

RESUMO

Goodpasture's syndrome complicating pregnancy is extremely rare and dialysis requiring anti GBM disease with renal recovery is uncommon. We report a case of a 23-year-old primi gravida who presented with Goodpasture's syndrome during thirteenth week of pregnancy. She was initiated on steroids and cytotoxic drugs along with intensive plasma exchange and alternate day hemodialysis. Her pregnancy was terminated at 15 weeks. Patient improved dramatically with treatment, her renal functions normalized and her Anti GBM antibody titer became negative.


Assuntos
Aborto Terapêutico , Doença Antimembrana Basal Glomerular/terapia , Plasmaferese , Complicações na Gravidez/terapia , Diálise Renal , Feminino , Humanos , Gravidez , Adulto Jovem
18.
Indian J Med Sci ; 60(7): 300-7, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16864916

RESUMO

Workers in information technology (IT)-enabled services like business process outsourcing and call centers working with visual display units are reported to have various health and psycho-social disorders. Evidence from previously published studies in peer- reviewed journals and internet sources were examined to explore health disorders and psycho-social problems among personnel employed in IT-based services, for a systematic review on the topic. In addition, authors executed a questionnaire- based pilot study. The available literature and the pilot study, both suggest health disorders and psychosocial problems among workers of business process outsourcing. The details are discussed in the review.


Assuntos
Terminais de Computador , Doenças Profissionais/fisiopatologia , Telefone , Ergonomia , Feminino , Humanos , Masculino , Fatores de Risco , Meio Social , Inquéritos e Questionários
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