Introduction about 3d cell culture

Cell culture consists in growing cells in an artificial environment in order to study their behavior in response to their environment. Different kinds of cell cultures can be found nowadays, and some would be more suited than others depending on its properties and applications.

Amongst them, 3D cell culture has been increasingly used for its new and convenient features compared to other alternative cell culture method. 3D cell culture could be described as the culture of living cells within micro-assembled devices and supports that present a three dimensional structures mimicking tissue and organ specific microarchitecture. In literature, there are some commendable reviews tackling 3D cell culture in-depth such as  John W. Haycock et al. “3D Cell Culture: A Review of Current Approaches and Techniques”, and this review mostly relies on those excellent references.

2D cell culture has traditionally been used over the past decades not only to study different cellular types in vitro but also to conduct drug screening and testing. Typically, this monolayer system allows cell growth over a polyester or glass flat surface presenting a medium that feeds the growing cell population. Countless biological breakthroughs occurred thanks to 2D cell culture. However due to its simplicity, this model can’t accurately depict and simulate the rich environment and complex processes observed in vivo such as cell signaling, chemistry or geometry. Consequently, data gathered with 2D cell culture methods could be misleading and non-predictive for in vivo applications. That’s the reason why scientists have recently been working on three-dimensional biomimetic cell cultures, a technique that represents more precisely the actual microenvironment in which cells can thrive in vivo.

As you may already be aware of, there are different type of 3D cell culture, with each kind of them offering different avantages and drawbacks. Unlike 2D cell culture, 3D cell culture facilitate cell differentiation and tissue organization by using micro-assembled structures and a complex environmental parameters. In fact, in a 3D environment, cells tend to be more subjected to morphological and physiological changes contrary to those grown in a 2D environment. This can mostly be explain by the structuring role and the influence of the scaffold that guide the cells behavior. Researchers have found that the geometry and composition of this cellular support can not only influence genes expression but also enhance cell-cell communication. For instance, some genes promoting cell proliferation are repressed in a 3D cell culture, hence avoiding the anarchic proliferation encountered in 2D cell cultures.

3D cell culture also grants the possibility to grow simultaneously two different cellular populations with co-cultures accurately reproducing cellular functions observed within a tissue unlike co-cultures based on 2D cell culture. Interactions existing between cells of interest and others cell are obviously key element in cell functions. That’s the reason why studies focusing on stromal cell (organ connective cell tissues) that play an important part in cancer have been conducted. Finally, using 3D cell culture make it easier to control and monitor the growing cells micro-environment parameters (temperature, chemical gradients, oxygen rate, pH, etc.) to a certain extent while remaining as close to reality as possible thanks to micro-engineering (microfluidic).

One must bear in mind that 3D cell culture is a relatively new technique that researchers have not yet fully grasped the underlying phenomenon and implications. Unfortunately, this culture method presents some noticeable downsides that would most likely be overcome by technological advances. First, some scaffold matrices incorporate compounds from animal or others unwanted sources (virus, soluble factors) that could interfere with the cell culture. Some other matrices provide good cell adherence, making cell removal all the more difficult. Beside, while 3D cell culture could be a cost saving technique that would skip the animal drug testing step in drugs trials, developing automation and reproducible applications still remains a very costly and meticulous process.

Everything required to know regarding Protein purification

Source Assortment:

Proteins with identical capabilities are found in several organisms, naturally the variant in the homes of a particular protein is considerable based on the source. A number of criteria should be followed pertaining to the selection of the original source, among these kinds of it is easy to get hold of it and the protein utilised in the source can be acquired in large quantities. Today, due to the molecular cloning tecinicas, new approaches have been made to obtain aminoacids.

Solubilization Methods

The first step intended for the solubilization of a necessary protein is their location within a solution, however this primary must be released from the cell. For this you ought to submit the cell into a lysis procedure. Osmotic lysis can be used in the event the cell is of animal source, if it is a bacterium or perhaps plant cellular, an enzyme capable of degrading the cell wall is used, for example: lysosim to get bacteria.

as well mechanical strategies are used for the irruption in the cell, which can include yellow sand or alunima, among these kinds of is the usage of juicer, homogenizers, mortars, sonicacion, etc . These processes happen to be accompanied by a next step of séchage or purification.

Stabilization

After the protein is removed from it is natural environment, it is actually exposed to various agents which could damage it. these impact on must be thoroughly controlled. the proteins may be affected by pH, temperature, proteases, oxidation of disulphide links, contamination by simply heavy mining harvests, salt focus, etc . These variables may be controlled with the use of buffers, preserve low temperature, usage of inhibitors, etc .

Essays

More about protein purification is necessary to detect its presence to indicate its purity. A protein is found in small quantities in each cell, so due to its detection it is necessary to use delicate and certain sheets. These types of tests has to be repeated each and every step in the purification. the proteins can be monitored corresponding to their spectroscopic or fluorescence characteristics, enzymatic assays can be executed when ideal (protein to get purified = enzyme).
As well, it is possible to use antibodies for the detection of protein through the ELISA test. In this one antibody is bound to an excellent matrix and is able to acknowledge our proteins. Then a second antibody binds to the complex formed by antibody 1, antibody2 is covalently certain to an enzyme capable of releasing a measurable item.

Purification Strategy

The purification of healthy proteins is completed by fractionation techniques. The physicochemical properties of the protein of interest will be used to separate it gradually from other chemicals. The idea is to minimize losing the desired health proteins, but selectively eliminate the other components of the mixture.

Uso de localizador gps na gestão de frotas

Vários particulares e empresas já possuem um localizador GPS nos carros, o que permite saber onde estão os veículos em caso de acidente ou roubo.

O Sistema de Posicionamento Global (GPS, na sigla em inglês – de Global Positioning System) é um sistema de localização por satélite, por vezes incorretamente considerado um sistema de navegação, utilizado para determinação da posição de um recetor na superfície da Terra ou em órbita.

O GPS foi criado originalmente para fins militares pelos EUA em 1973. Em 1983, foi autorizada a sua utilização por civis e tornou-se totalmente operacional em 1995.

Os primeiros carros com GPS

Atualmente é complementado por outros sistemas como o europeu Galileu, o russo Glosnass e o chinês Compass. A sua utilização civil mais difundida é a de, em conjunto com o GSM (Sistema Global para Comunicações Móveis) e mapas, servir para navegar, mostrando a localização do veículo, indicando percursos, a velocidade de deslocação e o tempo de viagem estimado. Os japoneses, com a Mazda à cabeça em 1990, foram os pioneiros na introdução da navegação por GPS; na Europa, o primeiro carro a ter um sistema desse tipo foi o BMW série 7 em 1994.

Porém, sendo na essência um sistema de localização e posicionamento de pessoas e objetos, as suas capacidades não se circunscrevem às de um mero sistema de navegação – uma das suas utilizações é o fornecimento em tempo real do local onde se encontra um determinado veículo e a sua movimentação. E, em conjunto com outros sistemas de conectividade, como o GSM, pode ser muito útil em caso de acidente ou roubo de um carro.

Vantagens do localizador GPS na gestão de frota

A possibilidade de poder localizar e controlar o percurso de veículos começou por ter uma aplicação profissional na gestão de frotas nos finais dos anos 90 do século passado.

O primeiro localizador de carros foi comercializado pelo israelita Haim Rodrik em 1994 mas ainda não se socorria do GPS – só no início deste século é que o mesmo Haim Rodrik desenvolveu um sistema que usava o GPS e o GSM para localizar os carros de uma forma mais precisa e eficiente.

De início, era algo caro e complexo que implicava algum investimento – não só para equipar as viaturas como para o pagamento mensal desses serviços. Porém, o seu desenvolvimento e expansão processaram-se a ritmo acelerado e, além de se tornar mais sofisticado, os custos baixaram consideravelmente sendo hoje muito comum na gestão de frotas.

Mais info sobre sistemas de gestão de frotas: http://www.tecmic.com/portfolio/izitran-gestao-de-frotas/