I'm using glossaries package to build a List of Symbols for my thesis template to obtain something like this:

and here is my MWE:
\documentclass{article}
\usepackage[automake]{glossaries}
\usepackage[english]{babel}
\usepackage{blindtext}
\newglossary{symbols}{sym}{sbl}{List of Abbreviations and Symbols}
\newglossaryentry{des}{type=symbols,name={DES},sort=des,
description={Discrete-Event Systems}}
\newglossaryentry{sct}{type=symbols,name={SCT},sort=sct,
description={Supervisory Control Theory}}
\makeglossaries
\begin{document}
\blindtext[3]
\gls{des}
\blindtext[3]
\blindtext[3]
\gls{sct}
\printglossaries
\end{document}
Leading to:
however, it is not exactly what it should be.
First of all, I need to add those dots between the description and the page number. Second, the glossary should have been printed before the text; since I need to place the List of Symbols right before the main text (just like List of Figures, etc.). But the problem is that I have to call \printglossaries right after all gls entries, then the list will be located at the end of the text.
How can I resolve these cases?
