dermie

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How Tattooing Really Works

1. Tattooing causes a wound that alerts the body to begin the inflammatory process, calling immune system cells to the wound site to begin repairing the skin. Specialized cells called macrophages eat the invading material (ink) in an attempt to clean up the inflammatory mess. 

2. As these cells travel through the lymphatic system, some of them are carried back with a belly full of dye into the lymph nodes while others remain in the dermis. With no way to dispose of the pigment, the dyes inside them remain visible through the skin. 

3. Some of the ink particles are also suspended in the gel-like matrix of the dermis, while others are engulfed by dermal cells called fibroblasts. Initially, ink is deposited into the epidermis as well, but as the skin heals, the damaged epidermal cells are shed and replaced by new, dye-free cells with the topmost layer peeling off like a healing sunburn.

4. Dermal cells, however, remain in place until they die. When they do, they are taken up, ink and all, by younger cells nearby so the ink stays where it is.

5. So a single tattoo may not truly last forever, but tattoos have been around longer than any existing culture. And their continuing popularity means that the art of tattooing is here to stay.

From the TED-Ed Lesson What makes tattoos permanent? - Claudia Aguirre

Animation by TOGETHER

Book cover concept for Les Misérables, written by Victor Hugo. I thought I would depict the poor Fantine. Very inspiring excercise. I was actually watching the 2000 French ‘telefilm’ adaptation with Gerard Depardieu as Valjean while doing it. I feel a bit sick though, I think I’m having a cold and it was even harder for me to draw snowy stuff while sneezing :p

Tengo tu esencia adherida a mi piel, tu tacto grabado como un tatuaje, una huella dérmica que quiero para siempre en mí, porque lejos de asustarme lo imborrable de tu paso por mi cuerpo, amo que seas la eternidad que me completa, y que inevitablemente me genera carencia, el amor que me hace feliz, pero me crea una vital dependencia.
—  Amour et entropie

Tattooing machines used today insert tiny needles, loaded with dye, into the skin at a frequency of 50 to 3,000 times per minute. The needles punch through the epidermis, allowing ink to seep deep into the dermis, which is composed of collagen fibers, nerves, glands, blood vessels and more.

From the TED-Ed Lesson What makes tattoos permanent? - Claudia Aguirre

Animation by TOGETHER

magic.wizards.com
Born of Aether
As the Inventors' Fair reaches full swing, the aetherborn socialite Yahenni throws a lavish party to celebrate. Chandra and Nissa join the guest list, searching for leads on Pia Nalaar.

Today’s Magic Story is Born of Aether, by Alison Luhrs. I’d like to give you all my thoughts on this one in greater detail than I usually do, explicit spoiler free.

The story is written in a way that I feel the emotion of all of its players. Yahenni’s fears and Nissa’s discomfort are laid bare like so much exposed aether from the fading dermis of an aetherborn. The tone loops about with the feelings of its participants, but never in a way that feels jostling, abrupt, or out of place. The adjective that encapsulates the emotion of the story overall is the one that’s been used to describe the aetherborns’ very existence. It’s bittersweet, and in that regard, it’s perfect. This story is already lovingly tucked into my mental library of favorites along with The Great Teacher’s Student and The Promised End.

Ultimately, this story granted me two differing streams of joy. The first was the rush of experiencing some truly masterful writing. The second is the emotion one feels after being shown the fruits of a dear friends’ labor. Alison, if you’re reading this, you’ve outdone yourself.

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The split skin graft; it involves the harvesting of a sheet of skin comprising epidermis and varying thickness of dermis, naturally this process involves the creation of a superficial wound that is the donor site, the donor site heals by a process of re-epithelialization; epithelial cells migrate across the wound surface from the rim of the wound and the edges of various structures in the dermal layer, such as sebaceous glands and hair follicles, this process results in an epithelial cover of the split-thickness skin graft donor site usually within 7–14 days. 

Schlegel’s Asity - Philepitta schlegeli

This fantastic bird is a Schlegel’s Asity male, and has the scientific name of Philepitta schlegeli (Passeriformes - Philepittidae). It is a forest dependent species endemic to Madagascar, listed as Near Threatened on the IUCN Red List. 

This species has elaborate secondary sexual characters. Adult breeding males of the Schlegel’s Asity have supraorbital caruncles, which are feather- less, fleshy excrescences of the dermis above the eye. These caruncles are pearly light green below and in front of the eyes, blue above the eyes, and turquoise behind the eyes.

References: [1] - [2] - [3]

Photo credit: ©Francesco Veronesi | Locality: Ankarafantsika, Madagascar (2014)

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The Skinny on Skin: Here’s Why It’s So Tough

by Lisa Marie Potter, Inside Science

Skin has to be flexible enough to jump, crawl, and kick with us. It also has to be resilient enough to withstand our falls, scrapes, and cuts. Scientists have marveled at skin’s strength for years without knowing why it’s so durable.

Now, scientists have identified the mechanical properties that give skin its toughness. Their findings are the first to show that collagen, the most abundant protein in skin, moves to absorb stress and prevent the skin from tearing. In the future, this knowledge could help us use nature’s blueprint to make better synthetic skin and improve the strength of man-made materials.  

“[Skin’s] tear resistance is remarkable,” said the study’s co-author Robert Ritchie, a professor of engineering at the University of California, Berkeley and Lawrence Berkeley Laboratory. “Quite frankly, what surprised me is that we couldn’t break the stuff to begin with.”

The secret weapon lies in the dermis, the thickest of the skin’s three layers. This middle layer mostly consists of strong tendrils of collagen. The article, published last month in Nature Communications, described how collagen’s structure allows it to efficiently distribute pressure and prevent tearing.

Keep reading

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Placoid scales aka dermal denticles are found in cartilaginous fishes such as sharks, rays, and chimaeras. 

They are also structurally homologous with vertebrate teeth (“denticle” translates to “small tooth”), having a central pulp cavity supplied with blood vessels, surrounded by a conical layer of dentine, all of which sits on top of a rectangular basal plate that rests on the dermis. 

The shape of denticles is specific to individual species and cannot grow in size, but rather more scales are added as the fish increases in size. 

  • SEM image of Banded Wobbegong Shark (Orectolobus ornatus), Brier Shark (Deania calcea), Tiger Shark (Galeocerdo cuvier) and Gummy Shark (Mustelus antarctius) denticles.
  • all photographs by Sue Lindsay/ Australian Museum 
Nasıl desem gözlerimi doldurdu,gitti.İnsan sevdiğine bari böyle gitseydi dermi abi öyle acıttı canımı bari ağlatıp öyle gitseydi diyorum.Böyle gözlerimi doldurup gitmesi daha başka acıtıyor.O gözyaşlarımın içime akması.... yakması,başka bi acı abi izah edemem.
Skin Grafts

Today I did two cases, both skin grafts. One with a Burn Surgeon and the other with a Plastic Surgeon. 
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Skin Grafts are often used for burn patients; skin is removed from one area of the body and transplanted to another. There are two types of skin graft: split-thickness grafts in which just a few layers of outer skin are transplanted and full-thickness grafts, which involve all of the dermis. There is usually permanent scarring that is noticeable.

During a skin graft, a special skin-cutting instrument known as a dermatone removes the skin from an area (the donor site) usually hidden by clothing such as the buttocks or inner thigh. Once removed, the graft is placed on the area in need of covering and held in place by a dressing and a few stitches. The donor site is also covered with a dressing to prevent infection from occurring. Recovery time from a split-thickness skin graft is generally fairly rapid, often less than three weeks. For full-thickness skin graft patients the recovery time is a few weeks longer. Aside from burn patients, skin grafts can also be used during breast or nose reconstruction.
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Cancer invasion and metastasis transform a locally growing tumor into a systemic and live-threatening disease. But how tumor cells (green) migrate between organs is still largely a black box. Friedl and colleagues have developed a tool to watch cancer cells as they move through the skin of live mice. From these experiments, they’ve found that tumor migration is remarkably “plastic;” cells adapt their transportation styles for various tissue conditions and even remodel the tissue itself to facilitate mobility.

Image: An overview of invading melanoma cells in the mouse dermis, with tumor cells (green) using both single-cell and collective invasion along and into tissue structures. Tumor cells expressing E2-Crimson are (false-colored) green, and muscle fibers expressing GFP are orange. Nerve fibers and collagen are blue (third harmonic) and grey (second harmonic), respectively. AlexaFluor660-dextran is red.