N = three every)13 13 31 19 three each and every 2 two every single 3 each0 1 0 0 0 0 00 two 0 0 0 0 01 0 0 0 0 0 03.2.1. Anterior-Anterior (An-An) The skin on the posterior half in the upper arm was replaced with skin obtained in the anterior half of the contralateral upper arm though maintaining the proximodistal and dorsoventral axes from the skin unchanged (Figure three). The operated limbs regenerated generally ( 81 , 13/16) except for the rare occasions in which a 5-digit ( 13 , n = two) or 1-digit hand ( 6 , n = 1) formed around the decrease arm (Figure 3; Table two). 3.2.2. Posterior-Posterior (Pos-Pos) The skin on the anterior half with the upper arm was replaced with skin obtained from the posterior half on the contralateral upper arm, although keeping the proximodistal and dorsoventral axes on the skin unchanged (Figure four). The operated limbs regenerated usually ( 81 , 13/16) except for all those instances ( 19 , 3/16) in which a hand with supernumerary digits appeared (Figure four; Table 2). In one particular case ( six , n = 1), a hand appeared to possess lost its dorsoventral pattern and the excessive digits had been irregularly formed around the hand whose palm was missing. Inside the other circumstances ( 13 , n = 2), a butterfly-like hand was formed in which two pairs of symmetrical hands and reduce arms appeared to fuse horizontally along the midline. We in no way discovered any additional forearm formation in the limb.Biomedicines 2021, 9,9 ofFigure 3. Effects of Anterior-Anterior (An-An) skin grafting on limb regeneration. (A) Schematic showing the surgical approach. (B,C) Representative showing normal regeneration (n = 13). Bracket: grafted skin. (D,E) Rarely occurring abnormal limbs. (D) A limb having a 5-digit hand (n = 2). (E) A limb with a 1-digit hand in the tip (n = 1). The number close to the digit indicates digit quantity. X indicates the digit whose number could not be determined. The asterisk indicates the elbow. The arrow indicates the amputation position. dpa: day post amputation. Scale bars: five mm.Biomedicines 2021, 9,10 ofFigure 4. Effects of Posterior-Posterior (Pos-Pos) skin grafting on limb regeneration. (A) Schematic displaying the surgical method. (B,C) Representative showing regular regeneration (n = 13). (D ) Hardly ever occurring abnormal limbs. (D,E) A limb with excessive digits on a hand with impaired dorsoventral pattern (n = 1). (E) An enlarged image at a distinctive angle in the limb shown in (D). The palm was not recognized. (F ) Representative of a limb having a butterfly-like hand (n = two). The bracket indicates the grafted skin. The number close to the digit indicates digit number. X indicates the digit whose quantity could not be determined. The asterisk indicates the elbow. The arrow indicates the amputation position. (I) The skeleton with the limb shown in (H). Two pairs of symmetrical hands and lower arms appeared to fuse horizontally along the midline (along the radius and very first digit). In this Monoolein Metabolic Enzyme/Protease sample, the cartilage was partially stained blue. The arrowhead in (H) indicates a joint created at the proximal finish in the ulna. The posterior ulna articulated for the humerus as standard however the anterior ulna ended together with the radius, indicating that the anterior half from the regenerated limb was not entirely mirrored. dpa: day post amputation; u: ulna; r: radius; h: humerus. Scale bars: four mm (B ,F ); three mm (E); two mm (I).3.2.three. Ventral-Ventral (Ven-Ven) The skin around the dorsal half in the upper arm was replaced with skin obtained in the ventral half of your contralateral upper arm while maintaining the proximodistal and anteroposterior axes of t.