@Harshad Harshad Mayekar

Hello all,

Ever wondered how your nails regrow after you trim them or some of us bite them off! How does hair grown back? A common answer would be that nail and hair are proteins, but yes what next.
Voting! Discussions amongst CUBISTS from several places in India has found an interesting way to understand this. Why not use the election ink mark (elections are being held in several places) to study regneration? This way we get everybody involved.
The ink used during voting is put across the fore finger. With time it moves ahead. That indirectly tells us that our nail is growing. How fast is this growth? Is it similar across all? Does sex, age have an effect of nail growth? Measuring movement of ink across nail provides a common platform to study rengeneration. All could contribute to this study at a national level.
Here we present photos of nails. We have tried to give a code to the name such that only the initials of the person are mentioned and there is no provision of personal information.
Here is an example.

We enter details like date of voting, the date the photo was taken, the person who collected the data and the serial number. Code is initials of two names of the person, the next number is for the combination for those two initials. Example the first time we get JV combination we can add JV1, the next time we encounter another person with JV initials it could be JV2. Next is sex, and age.
We also keep a ruler beside the finger to calculate the difference later (as standard). We could calculate how far the ink mark has gone from the inital point.

We would be updating more on this. If any of you would like to upload data, please do it here. We could make this a repository.


@dialecticalbiologist dilecticalbiologist

Mammalian digit-tip can regenerate upon amputation1,2, like amphibians. It is unknown why this capacity is limited to the area associated with the nail24. Here, we show that nail stem cells (NSCs) reside in the proximal nail matrix and that the mechanisms governing NSC differentiation are directly coupled with their ability to orchestrate digit regeneration. Early nail progenitors undergo Wnt-dependent differentiation into the nail. Upon amputation, this Wnt activation is required for nail regeneration and also for attracting nerves that promote mesenchymal blastema growth, leading to the regeneration of the entire digit. Amputations proximal to the Wnt-active nail progenitors result in the failure to regenerate the nail/digit (Supplementary Fig. S1). Nevertheless, β-catenin stabilization in the NSC region induced their regeneration. These results establish a link between NSC differentiation and digit regeneration, suggesting a utility of the NSCs in developing novel treatments for amputees.

Digit tip regeneration seen in both mice and humans involves the coordinated re-growth of the nail organ, including nail epithelial cells, and the terminal phalanx. Upon regrowth of the nail after amputation of the digit tip, undifferentiated mesenchymal cells including fate-restricted progenitor cells5,6 accumulate under the wound epithelium and form the so-called blastema7. Growth and differentiation of these mesenchymal cells leads to digit regeneration. However, neither nail nor digit regenerates when amputated proximally to the nail24,8,9 (Supplementary Fig. S2) and it is unknown why this limitation exists. Previous studies showed that nail transplantation following proximal digit amputation can induce ectopic digit bone differentiation4, leading to a hypothesis that the nail epithelium has a special function in digit regeneration. Testing this hypothesis may provide an understanding of why regeneration is limited to the nail-associated part of digits, and how epithelial cells can influence underlying mesenchymal cells to regenerate digit bone. The role of the nail epithelium in digit regeneration has remained elusive, due in part to the lack of lineage and molecular analyses of normal nail epithelium.


Update please! @Harshad