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Vesicle (biology and chemistry)

In cell biology, a vesicle is a structure within or outside a cell, consisting of liquid or cytoplasm enclosed by a lipid bilayer. Vesicles form during the processes of secretion and transport of materials within the plasma membrane. Alternatively, they may be prepared artificially. If there is only one phospholipid bilayer, they are called unilamellar liposome vesicles; the membrane enclosing the vesicle is a lamellar phase, similar to that of the plasma membrane, intracellular vesicles can fuse with the plasma membrane to release their contents outside the cell. Vesicles can fuse with other organelles within the cell. A vesicle released from the cell is known as an extracellular vesicle. Vesicles perform a variety of functions; because it is separated from the cytosol, the inside of the vesicle can be made to be different from the cytosolic environment. For this reason, vesicles are a basic tool used by the cell for organizing cellular substances. Vesicles are involved in metabolism, buoyancy control, temporary storage of food and enzymes.

They can act as chemical reaction chambers. The 2013 Nobel Prize in Physiology or Medicine was shared by James Rothman, Randy Schekman and Thomas Südhof for their roles in elucidating the makeup and function of cell vesicles in yeasts and in humans, including information on each vesicle's parts and how they are assembled. Vesicle dysfunction is thought to contribute to Alzheimer's disease, some hard-to-treat cases of epilepsy, some cancers and immunological disorders and certain neurovascular conditions. Vacuoles are cellular organelles which contain water. Plant cells have a large central vacuole in the center of the cell, used for osmotic control and nutrient storage. Contractile vacuoles are found in certain protists those in Phylum Ciliophora; these vacuoles take water from the cytoplasm and excrete it from the cell to avoid bursting due to osmotic pressure. Lysosomes are involved in cellular digestion. Food can be taken from outside the cell into food vacuoles by a process called endocytosis.

These food vacuoles fuse with lysosomes which break down the components so that they can be used in the cell. This form of cellular eating is called phagocytosis. Lysosomes are used to destroy defective or damaged organelles in a process called autophagy, they fuse with the membrane of the damaged organelle. Transport vesicles can move molecules between locations inside the cell, e.g. proteins from the rough endoplasmic reticulum to the Golgi apparatus. Membrane-bound and secreted proteins are made on ribosomes found in the rough endoplasmic reticulum. Most of these proteins mature in the Golgi apparatus before going to their final destination which may be to lysosomes, peroxisomes, or outside of the cell; these proteins travel within the cell inside of transport vesicles. Secretory vesicles contain materials. Cells have many reasons to excrete materials. One reason is to dispose of wastes. Another reason is tied to the function of the cell. Within a larger organism, some cells are specialized to produce certain chemicals.

These chemicals are released when needed. Synaptic vesicles are located at presynaptic terminals in neurons and store neurotransmitters; when a signal comes down an axon, the synaptic vesicles fuse with the cell membrane releasing the neurotransmitter so that it can be detected by receptor molecules on the next nerve cell. In animals endocrine tissues release hormones into the bloodstream; these hormones are stored within secretory vesicles. A good example is the endocrine tissue found in the islets of Langerhans in the pancreas; this tissue contains many cell types. Secretory vesicles hold the enzymes that are used to make the cell walls of plants, fungi and Archaea cells as well as the extracellular matrix of animal cells. Bacteria, Archaea and parasites release membrane vesicles containing varied but specialized toxic compounds and biochemical signal molecules, which are transported to target cells to initiate processes in favour of the microbe, which include invasion of host cells and killing of competing microbes in the same niche.

Extracellular vesicles are lipid bilayer-delimited particles produced by all domains of life including complex eukaryotes, both Gram-negative and Gram-positive bacteria and fungi. Ectosomes/microvesicles are shed directly from the plasma membrane and can range in size from around 30 nm to larger than a micron in diameter); these may include large particles such as Apoptotic blebs released by dying cells, large oncosomes released by some cancer cells, or "exophers," described in neuronal cell culture. Exosomes: membranous vesicles of endocytic origin. Different types of EVs may be separated based on size, or surface markers. However, EV subtypes have overlapping size and density ranges, subtype-unique markers must be established on a cell-by-cell basis. Therefore, it is difficult to pinpoint the biogeneesis pathway that gave rise to a particular EV after it has left the cell. In humans, endogenous extracellular vesicles play a role in coagulation, intercellular signaling and waste management, they are implicated in the pathophysiological processes involved in multiple diseases, including cancer.

Extracellular vesicles have raised interest as a potential source of biomarker discovery because of their role in intercellular communicat

Jorge Pulido

Jorge Pulido Mayoral is a Spanish footballer who plays for SD Huesca as a central defender. Born in Castillo de Bayuela, Castile-La Mancha, Pulido arrived in Atlético Madrid's youth system at the age of 10, he made his senior debut in the 2009 -- 10 season. On 10 November 2010, Pulido made his official debut with the Colchoneros's first team, playing the entire 1–1 home draw against Universidad de Las Palmas CF in the campaign's Copa del Rey. On 18 February of the following year, he extended his contract with the club by signing until 2014. On 15 May 2011, benefitting from injuries to Diego Godín and Luis Perea and the suspension of Tomáš Ujfaluši, Pulido made his first La Liga appearance, playing the full 90 minutes – with a good overall performance – and being booked after committing a penalty in a 2–1 home win against Hércules CF, as the club qualified to the UEFA Europa League. On 27 January 2012, he was loaned to fellow league team Rayo Vallecano until June. After being a regular starter with Rayo, Pulido returned to Atlético in the summer of 2012, but after being again underplayed he moved across the city to Real Madrid on 19 July 2013, being assigned to the reserves in the second level.

After suffering relegation with the latter he was released, subsequently joining Albacete Balompié in that tier. Pulido scored his first professional goal on 25 January 2015, netting his team's second in a 3–2 win at AD Alcorcón. Pulido participated in the 2008 UEFA European Under-17 Championship with Spain, helping his country to eventual victory in the tournament and scoring two goals. Atlético Madrid Copa del Rey: 2012–13 Spain U17 UEFA European Under-17 Championship: 2008 Jorge Pulido at BDFutbol Jorge Pulido at Futbolme Jorge Pulido – FIFA competition record Jorge Pulido at Soccerway

Look at Me (XXXTentacion song)

"Look at Me" is the debut single by American rapper XXXTentacion. The song premiered on December 30, 2015, on the SoundCloud account of Rojas, the song's co-producer, before being released for digital download as a single on January 29, 2016, becoming a sleeper hit in January 2017, in which the single was re-released for digital download again with a remastered and clean version of the single on February 20, 2017, by Empire Distribution; the song serves as the lead single from his debut commercial mixtape Revenge. The track was produced by Rojas and Jimmy Duval, samples the song "Changes" by British dubstep DJ and record producer Mala; the song was met with critical acclaim due to its production and XXXTentacion's style of rapping, peaked at number 34 on the US Billboard Hot 100. It has 174 million plays since its addition on SoundCloud, as well as over 348 million views on YouTube. "Look at Me" was certified Platinum by the Recording Industry Association of America on August 14, 2017, with over one million single-equivalent units.

In verified annotations added along with song's lyrics on Genius, the song's co-producer, spoke about how the song came together: One day me and X were sitting at the crib going through beats and he wasn't rocking with any of them, the last one I showed him was that beat, he was like, "Rojas, this is it!" In 15 minutes, it was done. X knew the whole song in his head before he made it. He's creative as fuck. X decided to distort the whole track in one. Rojas spoke about the origin of the beat: We made it at Jimmy Duval's Studio; the beat was made for Retch, when he came down to Miami after he had a show in Tampa. He was staying at Jimmy’s crib after I introduced them, when me and Jimmy decided to work on some stuff for Retch. That’s when we made the "Look At Me!" beat. We never got to send it to Retch because he went to jail and I lost contact with him and his management. Rojas lastly talked about how they found the sample: A couple months before I sampled it, I was listening to a song by Young Roddy called "Water" and I was fucking with him heavy.

I thought the sample was hard and I wanted to use it but I failed with it so many times before I got it right. The track, which has a tempo of 139 BPM samples "Changes" by British dubstep DJ and record producer Mala. "Look at Me" features an heavy and distorted bass, creating an aggressive feeling throughout the track. While some criticized the heavy distortion to be a case of bad mixing, the producer, said the poor mixing and distortion on the track was intentional to differentiate the song from other popular hip hop songs at the time. "Look at Me" debuted at number 94 on US Billboard Hot 100 for the chart dated February 25, 2017, has so far peaked at number 34. It is XXXTentacion's first charting single. However, this is his longest-charting song, making it into the Billboard Year-End Hot 100 singles of 2017 at number 99. "Look at Me" was certified Platinum by the Recording Industry Association of America on August 14, 2017 with over one million sales. The official music video for "Look at Me" was released on the artist's YouTube channel on September 12, 2017.

The video features both "Look at Me" and "Riot" by XXXTentacion. The song first received notable attention and controversy in early 2017 when Canadian rapper Drake used a similar rap flow from "Look at Me" in an unreleased song, it sparked a viral surge in the song's popularity, as well as Onfroy himself, while incarcerated at the time. Drake released the song "KMT" featuring English rapper Giggs on his commercial mixtape More Life, marketed as a "playlist."The song received further controversy in September 2017 when the music video was released depicting a white child being hung on stage in addition to other various depictions of murder and death. Although criticized by conservative news outlets, Onfroy clarified via Instagram that the video was meant to be taken as a form of art, that it was a form of shock value. Soon after, Onfroy claimed on an Instagram video that a member of the Ku Klux Klan had threatened him for the depictions in the song. Lyrics of this song at Genius Original audio on YouTube Re-release audio on YouTube