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1.
J Transl Med ; 21(1): 739, 2023 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-37858181

RESUMO

BACKGROUND: Hepatic ischemia-reperfusion (IR) injury is the primary reason for complications following hepatectomy and liver transplantation (LT). Insulin-induced gene 2 (Insig2) is one of several proteins that anchor the reticulum in the cytoplasm and is essential for metabolism and inflammatory responses. However, its function in IR injury remains ambiguous. METHODS: Insig2 global knock-out (KO) mice and mice with adeno-associated-virus8 (AAV8)-delivered Insig2 hepatocyte-specific overexpression were subjected to a 70% hepatic IR model. Liver injury was assessed by monitoring hepatic histology, inflammatory responses, and apoptosis. Hypoxia/reoxygenation stimulation (H/R) of primary hepatocytes and hypoxia model induced by cobalt chloride (CoCl2) were used for in vitro experiments. Multi-omics analysis of transcriptomics, proteomics, and metabolomics was used to investigate the molecular mechanisms underlying Insig2. RESULTS: Hepatic Insig2 expression was significantly reduced in clinical samples undergoing LT and the mouse IR model. Our findings showed that Insig2 depletion significantly aggravated IR-induced hepatic inflammation, cell death and injury, whereas Insig2 overexpression caused the opposite phenotypes. The results of in vitro H/R experiments were consistent with those in vivo. Mechanistically, multi-omics analysis revealed that Insig2 is associated with increased antioxidant pentose phosphate pathway (PPP) activity. The inhibition of glucose-6-phosphate-dehydrogenase (G6PD), a rate-limiting enzyme of PPP, rescued the protective effect of Insig2 overexpression, exacerbating liver injury. Finally, our findings indicated that mouse IR injury could be attenuated by developing a nanoparticle delivery system that enables liver-targeted delivery of substrate of PPP (glucose 6-phosphate). CONCLUSIONS: Insig2 has a protective function in liver IR by upregulating the PPP activity and remodeling glucose metabolism. The supplementary glucose 6-phosphate (G6P) salt may serve as a viable therapeutic target for alleviating hepatic IR.


Assuntos
Hepatócitos , Insulinas , Hepatopatias , Traumatismo por Reperfusão , Animais , Camundongos , Antioxidantes/metabolismo , Apoptose/genética , Glucose/metabolismo , Hepatectomia/efeitos adversos , Hepatócitos/metabolismo , Hepatócitos/patologia , Hipóxia/complicações , Hipóxia/genética , Hipóxia/metabolismo , Insulinas/metabolismo , Fígado/irrigação sanguínea , Fígado/lesões , Fígado/metabolismo , Fígado/patologia , Hepatopatias/genética , Hepatopatias/metabolismo , Hepatopatias/patologia , Hepatopatias/cirurgia , Transplante de Fígado/efeitos adversos , Fosfatos/metabolismo , Fosfatos/farmacologia , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/prevenção & controle
2.
Sci Rep ; 11(1): 20503, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34654851

RESUMO

Magnetotactic bacteria are microscale complex natural systems that synthesize magnetic nanoparticles through biologically controlled mineralization. Nanoparticles produced by this process are biocompatible due to the presence of surrounding membranes. The mechanism controlling synthesis is cost-effective and is executed by complex genomes (operons). The results are monodispersed magnetic nanoparticles displaying advantages over polydispersed ones synthesized by physical and chemical methods. In this work, we isolated Pseudomonas aeruginosa from clinical samples and demonstrated its ability to biosynthesize magnetic nanoparticles. P. aeruginosa was thrived in a carbon-minimal medium supplemented with iron at low pH. The cells aligned parallel to a magnetic field, confirming their magnetic properties. The magnetic nanoparticles were extracted, purified, and characterized using electron microscopy, magnetometry, dynamic light scattering, and X-ray diffraction. This work represents the first isolation of a magnetotactic bacterium from clinical samples. The aerobic nature of these bacteria allows them to be easily cultured under laboratory conditions, unlike their well-known microaerophilic counterparts. The biosynthesized magnetic nanoparticles can be used in many applications, including magnetic resonance imaging, diagnostics, and therapeutics (i.e., magnetic hyperthermia).


Assuntos
Nanopartículas Magnéticas de Óxido de Ferro , Magnetossomos , Pseudomonas aeruginosa/metabolismo , Nanopartículas Magnéticas de Óxido de Ferro/ultraestrutura
3.
Chemosphere ; 277: 130328, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33794428

RESUMO

Water scarcity and its pollution has become a concern in recent times. The disposal of nutrient-rich (nitrogen and phosphorous) wastewater is also one of the main cause of water pollution through eutrophication, reduced dissolved oxygen that poses threat to aquatic ecosystems. As a result, nutrient removal has become a mandate apart from the removal of organics. However, the removal of nutrients from sewage is a challenging task. Conversely, conventional biological treatment processes provide little relief in nutrient removal. The treated effluents from conventional biological processes do not achieve the stringent nutrient removal disposal standard limits and become primary cause of pollution in the receiving water bodies. This has stressed upon the need for eco-friendly, low-energy and cost-efficient nutrient removal treatment technologies. Various biological treatment combinations or variants are in use for the efficient removal of nutrients. The biological processes in itself or in combination with chemical processes are preferred over technologies based solely on physico-chemical processes for its treatment performance at lower cost. This review summarizes the existing treatment processes and their possible up-gradation with the aim to accomplish the marked effluent standards for the nutrients. The concept of conventional systems and advanced systems for nutrients (nitrogen and phosphorous) removal which are already developed or under development are deeply discussed. Further, the challenges of each treatment systems are abridged. Finally, the possible suggestions for the modification/retrofitting of existing treatment systems for achieving stringent disposal standards are pointed out.


Assuntos
Eliminação de Resíduos Líquidos , Águas Residuárias , Reatores Biológicos , Ecossistema , Nitrogênio , Nutrientes , Fósforo , Esgotos
4.
Work ; 68(3): 619-632, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33612507

RESUMO

BACKGROUND: Vibration therapy (VT) causes an increase in motor unit activation tendency, an involuntary recruitment of earlier sedentary motor units, which increases the muscle fiber force generating capacity and muscle performance. OBJECTIVE: To evaluate the effect of vibratory massage therapy at 23 Hz and 35 Hz on grip strength, endurance, and forearm muscle performance (in terms of EMG activity). METHODS: Ten healthy and right-handed men participated voluntarily in this study. The experiment was characterized by the measurement of MVC (maximal voluntary contraction) grip strength and grip endurance time at 50%MVC, accompanied by the corresponding measurement of the EMG signals of the muscles viz., flexor digitorum superficialis (FDS); flexor carpi ulnaris (FCU); extensor carpi radialis brevis (ECRB); and extensor carpi ulnaris (ECU) in supine posture. RESULTS: MANCOVA results showed significant effects of VT frequency on endurance time (p < 0.001); but no significant effect on the grip strength (p = 0.161) and muscle performance (in terms of EMG activities of the forearm muscles). However, VT improves the MVC grip strength and grip endurance time (better at 35 Hz). The Pearson correlation was significant between: weight, palm length, palm circumference, and forearm length with MVC grip strength; and the palm length with the endurance time. In addition, the palm length, palm circumference, and forearm circumference generally serve to better predict MVC grip strength and grip endurance time. CONCLUSIONS: Vibration therapy at 35 Hz for 10 minutes on the forearms had a significant positive effect on the neuromuscular performance to enhance muscle performance of upper extermitites and can be used as the optimal range to study the effect of VT. Findings may be used to prepare guidelines for VT in rehabilitation, healthcare, sports, and medical for therapists.


Assuntos
Antebraço , Músculo Esquelético , Eletromiografia , Força da Mão , Humanos , Masculino , Massagem , Força Muscular
5.
J Bodyw Mov Ther ; 24(4): 325-335, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33218530

RESUMO

BACKGROUND: Vibration Therapy (VT) stimulate the muscle spindles, which in turn enhances its afferent activities. OBJECTIVE: The present study was designed to investigate the effect of VT at 23 and 35 Hz on muscle performance. The EMG features (six time-domain (TD) and four frequency-domain (FD)) and a new formula for computing neuromuscular performance were used as dependent variables to evaluate the effect of VT. METHOD: The EMG recording was performed at 50% MVC during grip endurance test before and after VT. The EMG features were extracted out of raw EMG signals acquired from four forearm muscles, viz., flexor digitorum superficialis (FDS); flexor carpi ulnaris (FCU); extensor carpi radialis brevis (ECRB); and extensor carpi ulnaris (ECU) in supine position. Fatigue assessments were evaluated based on the pattern of TD and FD features. RESULTS: Statistical analysis showed a significant difference in the effect of vibration exposure frequency on IEMG (p < 0.001), MAV (p = 0.041), SSI (p = 0.032), and WL (p < 0.001) of FCU muscle. In addition, the greatest increase in neuromuscular efficiency (NME) was observed in the performance of ECRB after 35 Hz of VT and ECU muscles after 23 Hz of VT. CONCLUSIONS: The features of EMG signals could be used for fatigue analysis. However, the slope based on the median frequency regression line may be the best feature for fatigue assessment.


Assuntos
Antebraço , Vibração , Eletromiografia , Força da Mão , Humanos , Músculo Esquelético
6.
Curr Med Sci ; 40(6): 1067-1074, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33428134

RESUMO

Glioblastoma multiforme, an intrusive brain cancer, has the lowest survival rate of all brain cancers. The chemotherapy utilized to prevent their proliferation and propagation is limited due to modulation of complex cancer signalling pathways. These complex pathways provide infiltrative and drug evading properties leading to the development of chemotherapy resistance. Therefore, the development and discovery of such interventions or therapies that can bypass all these resistive barriers to ameliorate glioma prognosis and survival is of profound importance. Medicinal plants are comprised of an exorbitant range of phytochemicals that have the broad-spectrum capability to target intrusive brain cancers, modulate anti-cancer pathways and immunological responses to facilitate their eradication, and induce apoptosis. These phytocompounds also interfere with several oncogenic proteins that promote cancer invasiveness and metastasis, chemotherapy resistance and angiogenesis. These plants are extremely vital for promising anti-glioma therapy to avert glioma proliferation and recurrence. In this review, we acquired recent literature on medicinal plants whose extracts/bioactive ingredients are newly exploited in glioma therapeutics, and also highlighted their mode of action and pharmacological profile.


Assuntos
Neoplasias Encefálicas/metabolismo , Redes Reguladoras de Genes/efeitos dos fármacos , Glioblastoma/metabolismo , Compostos Fitoquímicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Humanos , Compostos Fitoquímicos/uso terapêutico , Plantas Medicinais/química , Prognóstico
7.
Mater Sci Eng C Mater Biol Appl ; 80: 526-531, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28866196

RESUMO

Magnetotactic bacteria provide an interesting example for the biosynthesis of magnetic (Fe3O4 or Fe3S4) nanoparticles, synthesized through a process known as biologically controlled mineralization, resulting in complex monodispersed, and nanostructures with unique magnetic properties. In this work, we report a novel aerobic bacterial strain isolated from sludge of an oil refinery. Microscopic and staining analysis revealed that it was a gram positive rod with the capability to thrive in a medium (9K) supplemented, with Fe2+ ions at an acidic pH (~3.2). The magnetic behaviour of these cells was tested by their alignment towards a permanent magnet, and later on confirmed by magnetometry analysis. The X-ray diffraction studies proved the cellular biosynthesis of magnetite nanoparticles inside the bacteria. This novel, bio-nano-magnet, could pave the way for green synthesis of magnetic nanoparticles to be used in industrial and medical applications such as MRI, magnetic hyperthermia and ferrofluids.


Assuntos
Magnetismo , Coloides , Nanopartículas de Magnetita , Difração de Raios X
8.
Pharm Biol ; 55(1): 1927-1930, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28659001

RESUMO

CONTEXT: Traditionally, Rhododendron arboreum Sm. (Ericaceae) is a very important medicinal plant having oxytocic, estrogenic, anti-inflammatory, analgesic and hepatoprotective activities; it also inhibits the prostaglandin synthetase. OBJECTIVES: This study determines the cytotoxic potential of 15-oxoursolic acid isolated from R. arboreum against selected human cancer cell lines. MATERIALS AND METHODS: Extraction from stem bark (5 kg) of R. arboreum was performed with methanol, which was successively partitioned into hexane, dichloromethane and ethyl acetate fractions, respectively. The new antitumor agent [15-oxoursolic acid (1)] was isolated from ethyl acetate fraction through column chromatography. Structure elucidation of new compound was performed through extensive spectroscopy i.e., IR, MS and 1D and 2D NMR. Cytotoxicity of isolated compound was determined at doses 5-100 µM for a period of 72 h on specified human cancer cell lines [renal cell carcinoma (A498), non-small cell lung (NCI-H226), squamous cell carcinoma (H157) and human ovarian carcinoma (MDR-2780AD)]. RESULTS: Structure of isolated compound was characterized as 15-oxoursolic acid on the basis of various extensive spectroscopic techniques. 15-Oxoursolic acid revealed considerable anticancer activity with IC50 values of 2.3 ± 0.1 µM, 4.9 ± 0.2 µM, 9.2 ± 0.2 µM and 10.3 ± 0.1 µM against MDR 2780AD, Hep G2, H157 and NCI-H226, respectively, while in the case of A498, the activity was good (IC50 32.8 ± 1.2 µM). CONCLUSIONS: This study highlighted the potential of 15-oxoursolic acid to be further explored as a new lead compound for cancer chemotherapy.


Assuntos
Citotoxinas/toxicidade , Triterpenos Pentacíclicos/toxicidade , Casca de Planta , Extratos Vegetais , Caules de Planta , Rhododendron , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Citotoxinas/química , Citotoxinas/isolamento & purificação , Avaliação Pré-Clínica de Medicamentos/métodos , Células Hep G2 , Humanos , Triterpenos Pentacíclicos/química , Triterpenos Pentacíclicos/isolamento & purificação
9.
IET Nanobiotechnol ; 10(4): 195-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27463789

RESUMO

Virgin coconut oil (VCO) is the finest grade of coconut oil, rich in phenolic content, antioxidant activity and contains medium chain triglycerides (MCTs). In this work formulation, characterisation and penetration of VCO-solid lipid particles (VCO-SLP) have been studied. VCO-SLP were prepared using ultrasonication of molten stearic acid and VCO in an aqueous solution. The electron microscopy imaging revealed that VCO-SLP were solid and spherical in shape. Ultrasonication was performed at several power intensities which resulted in particle sizes of VCO-SLP ranged from 0.608 ± 0.002 µm to 44.265 ± 1.870 µm. The particle size was directly proportional to the applied power intensity of ultrasonication. The zeta potential values of the particles were from -43.2 ± 0.28 mV to -47.5 ± 0.42 mV showing good stability. The cumulative permeation for the smallest sized VCO-SLP (0.608 µm) was 3.83 ± 0.01 µg/cm(2) whereas for larger carriers it was reduced (3.59 ± 0.02 µg/cm(2)). It is concluded that SLP have the potential to be exploited as a micro/nano scale cosmeceutical carrying vehicle for improved dermal delivery of VCO.


Assuntos
Cápsulas/química , Lipossomos/química , Nanocápsulas/química , Óleos de Plantas/administração & dosagem , Creme para a Pele/administração & dosagem , Perda Insensível de Água/efeitos dos fármacos , Absorção Fisico-Química , Administração Cutânea , Animais , Cápsulas/administração & dosagem , Óleo de Coco , Composição de Medicamentos/métodos , Estabilidade de Medicamentos , Técnicas In Vitro , Teste de Materiais , Nanocápsulas/administração & dosagem , Nanocápsulas/ultraestrutura , Tamanho da Partícula , Óleos de Plantas/química , Ratos , Absorção Cutânea/efeitos dos fármacos , Absorção Cutânea/fisiologia
10.
Braz. arch. biol. technol ; 59: e16160062, 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951395

RESUMO

ABSTRACT The anticancer potential of aqueous extracts of tropical plants Ficus deltoidea and Labisia pumila were tested on human prostate carcinoma (DU145) cells. The effects of these extracts on the cells were observed through several tests such as cytotoxicity MTT assay, trypan blue exclusion assay (for cell viability), fluorescence and morphological observations. Both of the plant extracts had a growth repression effect on the cells with different concentrations. The best concentration (1x10-3 μg/mL) was chosen by determining their cytotoxic effects on human prostate cancer as well as fibroblast (normal) cells. The F. deltoidea extract showed more potency and killed the cells faster than L. pumila. Morphologically both extracts affected the cells in a similar way, i.e. the cells became irregular shaped, detached themselves and kept floating in the medium.

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