Yes the issue is there.
Note that when using addslashes() on a string that includes cyrillic characters, addslashes() totally mixes up the string, rendering it unusable.
No of solution's
1) use mysql_real_escape_string instead of addslashes
2) try below code like str_replace
$myString = str_replace("'", "\'", $myString);
$myString = str_replace('"', "'+String.fromCharCode(34)+'", $myString);
if you have stil issue just let me know.
Regards