Getting my initials in logo style

Can you help me out to achieve what’s on the attached picture? It has to be with the same background circle and color.

mwe:

documentclass{article} 
usepackage{amsmath}

DeclareMathOperator{mr}{MMRkern R} newcommand{MRkern}{%   mkern-6.5mu   mathchoice{}{}{mkern0.2mu}{mkern0.5mu}% }

begin{document}

$mr$ $scriptstylemr$ $scriptscriptstylemr$

end{document}

documentclass{article}
usepackage{tikz}

defMD{%
begin{tikzpicture}
    draw[text=white,font=Largesffamily,draw=none,fill={rgb:red,54;green,58;blue,142}] (0,0) circle[radius=.8cm] node {MD};
end{tikzpicture}
}

begin{document}
Test: MD
end{document}