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1.
MethodsX ; 10: 102085, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36926271

RESUMO

Stereology and semiautomated binary image histomorphometry are two common methods used for morphometry of nerve fibres. Nucleator probe can be used for the estimation of morphometric parameters like diameter, perimeter, area and volume of a structure that is approximately either a circle or a sphere. In this study, we estimated these parameters with the help of ImageJ software on calibrated transmission electron micrographs. We procured samples of the cochlear nerve (CN) during winter months, within 6-12 hours of death, to reduce post-mortem autolytic changes. The temporal bones containing the CN were fixed by immersion in chilled paraformaldehyde. After dissecting out from the petrous part of the temporal bone, the CN were osmicated and processed for embedding in resin. From the resin blocks, silver coloured (70 nm) ultrathin sections were cut and picked on 300-mesh copper grids, stained with uranyl acetate and lead citrate and viewed under Tecnai G2-20 transmission electron microscope. The transmission electron micrographs had scale bars embedded into them by the software at the time of imaging, and the morphometric parameters of randomly selected nerve fibres were measured using the ImageJ software. The ImageJ software could become a low-cost and dependable tool for nerve fibre morphometry.•Nucleator probe is used for the estimation of morphometric parameters like diameter, perimeter, area or volume•Morphometric parameters were estimated by the ImageJ software on calibrated transmission electron micrographs•The ImageJ software could become a low-cost and dependable tool for nerve fibre morphometry.

2.
Int J Biol Macromol ; 193(Pt B): 1371-1378, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34757132

RESUMO

Nonenyl succinic anhydride (NSA) modification could be an alternative to octenyl succinic anhydride (OSA) modification of starch to obtain a range of physicochemical and rheological properties and for emulsification applications. A series of NSA-modified quinoa starches in granular form with different degrees of substitution (DS) (0.0080, 0.0175, 0.0359, and 0.0548) were prepared. The NSA modifications reduced the gelatinization temperatures and frequency dependence of storage modulus (G'), while increasing the peak viscosity, gel hardness, and G'. The NSA-modified quinoa starches with medium DS were the most effective in stabilising Pickering emulsions. The droplet size of Pickering emulsions decreased first with increasing DS before increasing at the highest DS. Modified starch with a DS of 0.0359 had the highest emulsifying capacity. Apart from the commonly used octenyl succinic anhydride (OSA) modification, the NSA-modified starches could be potential candidates as efficient Pickering emulsion stabilizers.


Assuntos
Chenopodium quinoa/química , Emulsões/química , Amido/química , Anidridos Succínicos/química , Reologia/métodos , Viscosidade
3.
Food Chem ; 339: 128014, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33152857

RESUMO

The research of host insect-resistance is a hot spot in the field of controlling storage pests. However, the mechanism of host resistance to storage pests is still unclear. Some researchers think it is related to grain cracking characters of rice husk, while others have linked it to volatile compounds in rice grains. In this paper, using 117 micro-core germplasm resources of rice and the investigation on the rate of insect damage, sixteen materials with different insect-resistance and four with significant difference in insect resistance were selected. Pentanamide, a volatile compound in rice, was analyzed by gas chromatography-mass spectrometry (GC-MS) and found to be negatively correlated with the rate of insect damage of rice materials. The bioassay results showed that 8% Pentanamide had a good effect on controlling storage pests and trapping pests. This study provided direct evidence for the correlation between rice volatile compounds and their host insect-resistant mechanisms.


Assuntos
Armazenamento de Alimentos , Insetos , Oryza/química , Controle Biológico de Vetores/métodos , Compostos Orgânicos Voláteis/análise , Animais
4.
Curr Org Synth ; 17(6): 488-495, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32427085

RESUMO

BACKGROUND: The phthalocyanines a series of compounds involves four iso-indole units linked by aza nitrogen atoms bonded with metal atoms that are normally located in the center a phthalocyanines ring. Some of the central metal-phthalocyanines can be excited by ultraviolet light and emit a fluorescence in far-red region. OBJECTIVE: To synthesize a derivative of phthalocyanines namely 4,4',4' '-tri-(dodecenyl succinic anhydride)- 4' ' '-(5-amino salicylic acid) zinc phthalocyanine with a zinc central metal. MATERIALS AND METHODS: The reaction of 4- nitro Phthalonitrile and 4- amino Phthalonitrile with ZnCl2 in the presence of dimethyl amino ethanol afforded 4,4',4' '-triamino-4' ' '-nitro zinc phthalocyanine. This product reacted with 5-amino salicylic acid to yield tetra-(5-amino salicylic acid) zinc phthalocyanine. A dodecenyl succinic anhydride was added on the amine group of benzoic rings to afford 4,4',4' '-tri-(dodecenyl succinic anhydride)-4' ' '-(5-amino salicylic acid) zinc phthalocyanine(I), the target compound. RESULTS AND DISCUSSION: Compound I is successfully synthesized with a yield of 72% from tetra-(5-amino salicylic acid) zinc phthalocyanine with dodecenyl succinic anhydride. CONCLUSION: The newly synthesized molecule of 4,4',4' '-tri-(dodecenyl succinic anhydride)-4' ' '-(5-amino salicylic acid) zinc phthalocyanine (I), tetra-(5-amino salicylic acid) zinc phthalocyanine(E) and 4,4',4' '- triamino-4' ' '-nitro zinc phthalocyanine (S). The reaction of 4- nitro Phthalonitrile and 4- amino and the structure of compound I is confirmed and its formation was proven.

5.
Int J Biol Macromol ; 112: 1257-1263, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29454955

RESUMO

Starch-based adhesives were prepared by esterification modification with dodecenyl succinic anhydride (DDSA) and polyaryl polymethylene isocyanate (PAPI) as a crosslinking agent. DDSA modified starch (DMS) adhesives could significantly enhance the viscosity and adhesion strength of starch adhesives, making it beneficial to be applied in the field of plywood industry. This paper investigated the physicochemical properties of starch modified by dodecenyl succinic anhydride. Solid content, viscosity, adhesion, structural change and morphological features were characterized in detail. Viscosity and solid content of the modified starch (MF) adhesives was improved remarkably when DDSA was introduced. Three-ply plywood was fabricated with DMS adhesives, and its wet shear strength was measured. The results showed that the water resistance of the adhesive with 6wt% DDSA improved by 72.4% compared to that without DDSA. The wet shear strength plywood bonded by the adhesive reached 1MPa and could meet the requirement set by the China National Standard. Incorporating DDSA into the starch adhesive formed a dense crosslinking structure due to chemical reactions between DDSA and active groups on the starch molecules and thus improve the water resistance of the cured adhesives. The introduction of DDSA improving the viscosity and solid content remarkably, which increased the amount of the adhesive that penetrated the wood surface and formed more interlocks. Using DDSA promoted a smooth and homogeneous fracture surface of cured adhesive, which effectively prevented water intrusion and improved water resistance. The modified adhesive proved practical as a plywood adhesive for industrial application.


Assuntos
Adesivos/química , Fenômenos Químicos , Amido/química , Anidridos Succínicos/química , Esterificação , Espectroscopia Fotoeletrônica , Resistência ao Cisalhamento , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/ultraestrutura , Termogravimetria , Viscosidade
6.
Rev. chil. nutr ; 43(3): 284-289, set. 2016. graf, tab
Artigo em Espanhol | LILACS | ID: biblio-830137

RESUMO

Coatings are defined as edible products which form a thin layer on the food, and are characterized by it constitute a semipermeable barrier to gases and water vapor retarding food spoilage, improve the mechanical properties, help maintain the structural integrity of the product wrapping, to retain volatile compounds and can act as a vehicle for food additives. We evaluated the performance of the biofilms on melon through the determination of physico-chemical and sensory properties. The results show that all the variables are significantly influenced by the biomolecule employed "modified starch", noting a favorable performance in the edible biofilms.


Los recubrimientos se definen como productos comestibles que forman una fina capa sobre el alimento y se caracterizan por que constituyen una barrera semipermeable a los gases y al vapor de agua que retrasa el deterioro del alimento, mejoran las propiedades mecánicas, ayudan a mantener la integridad estructural del producto que envuelven, ayudan a retener compuestos volátiles y pueden actuar como vehículo de aditivos alimentarios. Se evaluó el desempeño de los biorecubrimientos sobre el melón mediante la determinación de propiedades sensoriales y fisicoquímicas. Los resultados muestran que todas las variables están significativamente influenciadas por la biomolécula empleada "almidón modificado", observando un desempeño favorable en los biorecubrimientos comestibles.


Assuntos
Amido , Anidridos Succínicos , Cucurbitaceae , Conservação de Alimentos , Tubérculos
7.
Neuroscience ; 247: 12-24, 2013 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-23673279

RESUMO

Schizophrenia is a severe condition that has been associated with functional abnormalities in dopaminergic (DA) neurons of the ventral tegmental area (VTA). Neurokinin-3 receptors (NK3Rs) of the tachykinin family of neuropeptides modulate the activity of VTA DA neurons and might be involved in DA abnormalities relevant to schizophrenia. Recent work from our lab showed that systemic injection of the dopamine D1/D2 receptor agonist apomorphine in rats, which mimics schizophrenia-like behaviors in humans, also evoked a redistribution of NK3Rs in DA neurons of the rat VTA. In the present study, VTA microinjection of the selective NK3R antagonist SB222200 (1 nmol/0.2 µl) or the nuclear import blocker SN50 (2 µg/0.2 µl) was performed in awake rats 10 min prior to systemic injection of apomorphine. VTA sections were dual immunolabeled for the NK3R (immunogold) and the dopamine synthesizing enzyme tyrosine hydroxylase (TH, immunoperoxidase). Electron microscopic quantifications of somatic and dendritic densities of NK3 immunogold particles were compared in rats receiving central and systemic injections. In DA (TH-labeled) dendrites, VTA microinjection of SB222200 prevented the apomorphine-evoked decrease in surface NK3R density as well as the apomorphine-induced increase in cytoplasmic NK3R density. In contrast, VTA microinjection of SN50, but not SB222200, prevented the apomorphine-induced increase in nuclear NK3R density. VTA microinjection of SB222200 or SN50 without apomorphine had no effect on the NK3R distribution or density in TH and non-TH profiles within the VTA. In non-TH, presumably GABAergic neurons of the VTA, the NK3R densities in somata and dendrites were not significantly changed by apomorphine with or without SB222200. The results suggest that the NK3R antagonist SB222200 is effective against the apomorphine-evoked NK3R internalization in VTA DA dendrites, but does not prevent nuclear NK3R trafficking in VTA DA neurons. These results might have important implications in targeting NK3R antagonists in basic or clinical studies.


Assuntos
Apomorfina/administração & dosagem , Núcleo Celular/efeitos dos fármacos , Neurônios Dopaminérgicos/efeitos dos fármacos , Quinolinas/administração & dosagem , Receptores da Neurocinina-3/antagonistas & inibidores , Área Tegmentar Ventral/efeitos dos fármacos , Animais , Membrana Celular/efeitos dos fármacos , Membrana Celular/ultraestrutura , Núcleo Celular/ultraestrutura , Neurônios Dopaminérgicos/ultraestrutura , Masculino , Microinjeções , Ratos , Ratos Sprague-Dawley , Receptores da Neurocinina-3/ultraestrutura , Área Tegmentar Ventral/ultraestrutura
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