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1.
Matrix Biol ; 124: 8-22, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37913834

RESUMEN

The circadian clock in tendon regulates the daily rhythmic synthesis of collagen-I and the appearance and disappearance of small-diameter collagen fibrils in the extracellular matrix. How the fibrils are assembled and removed is not fully understood. Here, we first showed that the collagenase, membrane type I-matrix metalloproteinase (MT1-MMP, encoded by Mmp14), is regulated by the circadian clock in postnatal mouse tendon. Next, we generated tamoxifen-induced Col1a2-Cre-ERT2::Mmp14 KO mice (Mmp14 conditional knockout (CKO)). The CKO mice developed hind limb dorsiflexion and thickened tendons, which accumulated narrow-diameter collagen fibrils causing ultrastructural disorganization. Mass spectrometry of control tendons identified 1195 proteins of which 212 showed time-dependent abundance. In Mmp14 CKO mice 19 proteins had reversed temporal abundance and 176 proteins lost time dependency. Among these, the collagen crosslinking enzymes lysyl oxidase-like 1 (LOXL1) and lysyl hydroxylase 1 (LH1; encoded by Plod2) were elevated and had lost time-dependent regulation. High-pressure chromatography confirmed elevated levels of hydroxylysine aldehyde (pyridinoline) crosslinking of collagen in CKO tendons. As a result, collagen-I was refractory to extraction. We also showed that CRISPR-Cas9 deletion of Mmp14 from cultured fibroblasts resulted in loss of circadian clock rhythmicity of period 2 (PER2), and recombinant MT1-MMP was highly effective at cleaving soluble collagen-I but less effective at cleaving collagen pre-assembled into fibrils. In conclusion, our study shows that circadian clock-regulated Mmp14 controls the rhythmic synthesis of small diameter collagen fibrils, regulates collagen crosslinking, and its absence disrupts the circadian clock and matrisome in tendon fibroblasts.


Asunto(s)
Colágeno , Metaloproteinasa 14 de la Matriz , Animales , Ratones , Ritmo Circadiano , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Homeostasis , Metaloproteinasa 14 de la Matriz/genética , Metaloproteinasa 14 de la Matriz/metabolismo
2.
Sci Rep ; 12(1): 4076, 2022 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-35260739

RESUMEN

Characterization of near-interface traps (NITs) in commercial SiC metal-oxide-semiconductor field-effect transistors (MOSFETs) is essential because they adversely impact both performance and reliability by reducing the channel carrier mobility and causing threshold-voltage drift. In this work, we have applied a newly developed integrated-charge technique to measure the density of NITs that are active in the above-threshold region of commercial SiC MOSFETs. The results demonstrate that NITs trap about 10% of the channel electrons for longer than 500 ns.


Asunto(s)
Semiconductores , Transistores Electrónicos , Óxidos , Reproducibilidad de los Resultados
3.
Physiol Mol Biol Plants ; 24(5): 985-992, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30150872

RESUMEN

Growth and physio-biochemical traits under different incident solar light intensities (100, 67, 50 and 25%) were studied in mustard in a semi-arid agroclimate region of Central India. Our comprehensive studies revealed that incident solar light intensities below about 67% were highly detrimental in mustard for its growth and grain yield. Major factors that contributed to the differential responses under varying light intensities were identified which holds importance for better understanding of low light adaptability in an important oilseed crop like mustard. Biomass index (ratio of dry biomass to height) has been established and evaluated for the differential growth performance of the crop under different light intensities. Biomass index progressively declined from 0.48 (open sunlight) to 0.11 (25% sunlight). Physio-biochemical factors were identified that were playing major role in manifestation of the differential growth and grain yield. Mustard exhibited its low light adaptive trends through differential down-regulation in the rates of net CO2 assimilation (PN), stomatal conductance, transpiration, thylakoid electron transport rate (ETR) and leaf wax level. For example, PN decreased from 35.88 (open light) to 11.64 µmol m-2 s-1 (25% sunlight). Photochemical events showed critical impact as evidenced by decreased PSII quantum yield, photochemical quenching (qP) and higher non-photochemical quenching (qN) that were clearly associated with physiological efficiency of the plants under varying light intensities. Leaf wax level decreased from 1.69 mg g-1 fresh weight (open light) to 0.96 mg g-1 fresh weight (25% sunlight). Our results indicated that limited ETR supply across photosystem II (PSII) decreased the photochemical efficiency and carbon gain under low light which resulted in reduction of biomass index and grain yield. Besides, it was found that overexpression of protein band around ~ 26 kDa in low light could be another adaptive feature for mustard related to light harvesting complex. Our findings would augment selection of traits for optimizing growth and grain yield of mustard for low light or light limiting agro-ecosystem.

4.
Ann Maxillofac Surg ; 8(1): 124-126, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29963438

RESUMEN

Pleomorphic adenoma (PA) is a benign tumor of the salivary glands commonly seen in the parotid and submandibular salivary glands. Rarely, it is seen in the minor salivary glands located at lips, palate, and other parts of the upper aerodigestive tract. We report a case of an unusually large PA of the hard palate in a female patient involving left maxillary sinus and nasal cavity. After excising, the tumor with adequate clinical margins (1 cm), a large postsurgical defect was managed by the use of obturator and it gradually healed by secondary intention in about 6-month period. The unique feature in our case was that in spite of the long duration of the tumor (30 years), it did not undergo malignant transformation.

5.
Adv Pharm Bull ; 7(4): 569-577, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29399546

RESUMEN

Purpose: A comparative study was carried out between surface solid dispersion (SSD) and solid dispersion (SD) of meloxicam (MLX) to assess the solubility and dissolution enhancement approach and thereafter develop as patient friendly orodispersible tablet. Methods: Crospovidone (CPV), a hydrophilic carrier was selected for SSD preparation on the basis of 89% in- vitro MLX adsorption, 19% hydration capacity and high swelling index. SD on the other hand was made with PEG4000. Both were prepared by co-grinding and solvent evaporation method using drug: carrier ratios of 1:1, 1:4, and 1:8. Formulation SSDS3 (MLX: CPV in 1:8 ratio) made by solvent evaporation method showed t50% of 28 min and 80.9% DE50min which was higher in comparison to the corresponding solid dispersion, SDS3 (t50% of 35min and 76.4% DE50min). Both SSDS3 and SDS3 were developed as orodispersible tablets and evaluated. Results: Tablet formulation F3 made with SSD3 with a disintegration time of 11 secs, by wetting time= 6 sec, high water absorption of 78%by wt and cumulative drug release of 97% proved to be superior than the tablet made with SD3. Conclusion: Conclusively, the SSD of meloxicam has the potential to be developed as fast acing formulation that can ensure almost complete release of drug.

6.
Int Marit Health ; 65(3): 106-13, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25471158

RESUMEN

BACKGROUND: Malocclusion is one of the most common dental problems in mankind. Planning orthodontic treatment as well as an interceptive approach within a public health system requires information on the prevalence of malocclusions. AIM: The aim of the study was to assess the prevalence of malocclusion and orthodontic treatment needs among 12-15-year-old school children of fishermen of Kutch coast, Gujarat, India. MATERIALS AND METHODS: A cross-sectional descriptive survey was conducted among 947 school children offishermen of Kutch coast, Gujarat, India aged 12-15 years. The prevalence of malocclusion and orthodontic treatment needs was assessed using Dental Aesthetic Index. General information on demographic data was also recorded. A c2 test, analysis of variance (ANOVA) and Sheffe's test were employed for statistical analysis. RESULTS: Malocclusion and orthodontic treatment need was reported among 33.4% of the participants. Younger age group and female gender had significantly greater treatment need. Males and older age groups had significantly lesser prevalence of anterior crowding and largest anterior maxillary irregularity. CONCLUSIONS: Orthodontic treatment need among 33.4% calls for developing school based oral health promotion programmes for children with an inculcation of orthodontic treatment and educational programmes for parents (fishermen) addressing prevention and early interceptive treatment of malocclusion.


Asunto(s)
Educación en Salud , Maloclusión/epidemiología , Ortodoncia Interceptiva , Adolescente , Factores de Edad , Niño , Estudios Transversales , Femenino , Industria de Alimentos , Necesidades y Demandas de Servicios de Salud , Humanos , India/epidemiología , Masculino , Maloclusión/terapia , Maloclusión de Angle Clase III/epidemiología , Evaluación de Necesidades , Mordida Abierta/epidemiología , Sobremordida/epidemiología , Prevalencia , Alimentos Marinos , Factores Sexuales , Estudiantes/estadística & datos numéricos
7.
Int J Nanomedicine ; 9: 575-88, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24531257

RESUMEN

AIM: The aim of this study was to develop poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) for delivery of a protein - tissue inhibitor of matrix metalloproteinases 1 (TIMP-1) - across the blood-brain barrier (BBB) to inhibit deleterious matrix metalloproteinases (MMPs). MATERIALS AND METHODS: The NPs were formulated by multiple-emulsion solvent-evaporation, and for enhancing BBB penetration, they were coated with polysorbate 80 (Ps80). We compared Ps80-coated and uncoated NPs for their toxicity, binding, and BBB penetration on primary rat brain capillary endothelial cell cultures and the rat brain endothelial 4 cell line. These studies were followed by in vivo studies for brain delivery of these NPs. RESULTS: Results showed that neither Ps80-coated nor uncoated NPs caused significant opening of the BBB, and essentially they were nontoxic. NPs without Ps80 coating had more binding to endothelial cells compared to Ps80-coated NPs. Penetration studies showed that TIMP-1 NPs + Ps80 had 11.21%± 1.35% penetration, whereas TIMP-1 alone and TIMP-1 NPs without Ps80 coating did not cross the endothelial monolayer. In vivo studies indicated BBB penetration of intravenously injected TIMP-1 NPs + Ps80. CONCLUSION: The study demonstrated that Ps80 coating of NPs does not cause significant toxic effects to endothelial cells and that it can be used to enhance the delivery of protein across endothelial cell barriers, both in vitro and in vivo.


Asunto(s)
Barrera Hematoencefálica/metabolismo , Sistemas de Liberación de Medicamentos , Ácido Láctico/química , Nanopartículas/administración & dosificación , Nanopartículas/química , Ácido Poliglicólico/química , Inhibidor Tisular de Metaloproteinasa-1/administración & dosificación , Animales , Barrera Hematoencefálica/efectos de los fármacos , Línea Celular , Células Cultivadas , Química Farmacéutica , Preparaciones de Acción Retardada , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Nanomedicina , Nanopartículas/toxicidad , Nanotecnología , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Polisorbatos/química , Ratas , Tensoactivos/química , Inhibidor Tisular de Metaloproteinasa-1/farmacocinética
8.
Indian Dermatol Online J ; 5(Suppl 2): S95-7, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25593816

RESUMEN

Lipoid proteinosis is a very rare autosomal recessive disorder characterized by deposition of hyaline material in the skin and the upper aerodigestive tract. Hoarseness of voice occurs very early in life and airway obstruction may occur. Characteristic skin lesions include multiple brown atrophic scars over face and distal extremities, beaded papules over the margins of the eyelids and verrucous nodules over the friction bearing areas (elbows, knees). The overall prognosis is good. There is no definitive treatment.

9.
Mol Neurobiol ; 49(1): 563-73, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24026771

RESUMEN

Ischemic stroke is a leading cause of disability worldwide. In cerebral ischemia there is an enhanced expression of matrix metallo-proteinase-9 (MMP-9), which has been associated with various complications including excitotoxicity, neuronal damage, apoptosis, blood-brain barrier (BBB) opening leading to cerebral edema, and hemorrhagic transformation. Moreover, the tissue plasminogen activator (tPA), which is the only US-FDA approved treatment of ischemic stroke, has a brief 3 to 4 h time window and it has been proposed that detrimental effects of tPA beyond the 3 h since the onset of stroke are derived from its ability to activate MMP-9 that in turn contributes to the breakdown of BBB. Therefore, the available literature suggests that MMP-9 inhibition can be of therapeutic importance in ischemic stroke. Hence, combination therapies of MMP-9 inhibitor along with tPA can be beneficial in ischemic stroke. In this review we will discuss the current status of various strategies which have shown neuroprotection and extension of thrombolytic window by directly or indirectly inhibiting MMP-9 activity. In the introductory part of the review, we briefly provide an overview on ischemic stroke, commonly used models of ischemic stroke and a role of MMP-9 in ischemia. In next part, the literature is organized as various approaches which have proven neuroprotective effects through direct or indirect decrease in MMP-9 activity, namely, using biotherapeutics, involving MMP-9 gene inhibition using viral vectors; using endogenous inhibitor of MMP-9, repurposing of old drugs such as minocycline, new chemical entities like DP-b99, and finally other approaches like therapeutic hypothermia.


Asunto(s)
Metaloproteinasa 9 de la Matriz/metabolismo , Inhibidores de la Metaloproteinasa de la Matriz/administración & dosificación , Fármacos Neuroprotectores/administración & dosificación , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/enzimología , Animales , Sistemas de Liberación de Medicamentos/tendencias , Inhibidores Enzimáticos/administración & dosificación , Humanos , Activador de Tejido Plasminógeno/administración & dosificación
10.
J Neurosci ; 33(36): 14591-600, 2013 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-24005309

RESUMEN

Learning how to avoid danger and pursue reward depends on negative emotions motivating aversive learning and positive emotions motivating appetitive learning. The amygdala is a key component of the brain emotional system; however, an understanding of how various emotions are differentially processed in the amygdala has yet to be achieved. We report that matrix metalloproteinase-9 (MMP-9, extracellularly operating enzyme) in the central nucleus of the amygdala (CeA) is crucial for appetitive, but not for aversive, learning in mice. The knock-out of MMP-9 impairs appetitively motivated conditioning, but not an aversive one. MMP-9 is present at the excitatory synapses in the CeA with its activity greatly enhanced after the appetitive training. Finally, blocking extracellular MMP-9 activity with its inhibitor TIMP-1 provides evidence that local MMP-9 activity in the CeA is crucial for the appetitive, but not for aversive, learning.


Asunto(s)
Amígdala del Cerebelo/fisiología , Condicionamiento Operante , Metaloproteinasa 9 de la Matriz/metabolismo , Recompensa , Amígdala del Cerebelo/metabolismo , Animales , Conducta Apetitiva , Metaloproteinasa 9 de la Matriz/efectos de los fármacos , Metaloproteinasa 9 de la Matriz/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neuronas/metabolismo , Neuronas/fisiología , Sinapsis/metabolismo , Sinapsis/fisiología , Inhibidor Tisular de Metaloproteinasa-1/farmacología
11.
Neurochem Int ; 61(7): 1065-71, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22892277

RESUMEN

Matrix metalloproteinases (MMPs) are family of zinc dependent endopeptidases, which cleave extracellular matrix proteins, and play an important role in tissue remodelling in physiological and pathological processes. There is enhanced expression of MMPs, in particular MMP-9, during numerous pathological conditions, including epilepsy and ischemic stroke. Therefore, inhibition of MMP-9 is considered as a potential therapeutic target. Tissue Inhibitor of Matrix Metalloproteinase-1 (TIMP-1) is a 28kDa endogenous inhibitor of MMP-9. In this study we examined recombinant mouse TIMP-1 for its in-vitro neuroprotective effects, against Kainic Acid (KA) induced excitotoxicity in organotypic hippocampal slice culture (OHC) model. We also studied, sustained release effects of TIMP-1 in OHC by using poly lactic-co-glycolic acid (PLGA) nanoparticles (NPs). TIMP-1 and TIMP-1 PLGA NPs were added to the slice cultures at different time points, i.e., 30min before treatment with KA and 6h after KA treatment. Propidium iodide staining was used to reveal cell toxicity in the cultures. In addition, neurotoxicity was assessed using standard lactate dehydrogenase (LDH) release assay. Gelatinolytic activity in conditioned cultured medium of OHC was accessed by a fluorescent substrate assay. Briefly, our result show that TIMP-1 provided significant level of neuroprotection, especially when given before 30min of KA and released from the NPs. Since gelatinolytic activity assay showed a decrease in MMP-9 activity, it can be suggested that this neuroprotection might be mediated by the gelatinase inhibition.


Asunto(s)
Nanopartículas , Fármacos Neuroprotectores/farmacología , Inhibidor Tisular de Metaloproteinasa-1/efectos adversos , Animales , Células HEK293 , Humanos , Ratas , Ratas Wistar , Proteínas Recombinantes/efectos adversos
12.
J Adv Pharm Technol Res ; 2(4): 215-22, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22247888

RESUMEN

This update review is on mucoadhesive polymers used in nasal dosage forms. The nasal mucosa provides a potentially good route for systemic drug delivery. One of the most important features of the nasal route is that it avoids first-pass hepatic metabolism, thereby reducing metabolism. The application of mucoadhesive polymers in nasal drug delivery systems has gained to promote dosage form residence time in the nasal cavity as well as improving intimacy of contact with absorptive membranes of the biological system. The various new technology uses in development of nasal drug delivery dosage forms are discussed. The various dosage forms are vesicular carriers (liposome, noisome), nanostructured particles, prodrugs, in situ gelling system with special attention to in vivo studies.

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