How to use metrics attribute in General/Info/Title


I us a singlestats panel and have the following metric define:
((up{instance=~"$host:.",job=~"."}) * on(instance) group_left(nodename) node_uname_info) or vector(-1)

I would like to display nodename in the General /info/title.

I tried {{nodename}}, [[nodename]] or $nodename, but any of them works.

There is away to display the nodename element in the title?

Same question for the prefix and postfix, seems the same problem.

Add missing information:
Prometheus: 2.1.0
Grafana: 4.6.2
$host is a templating variable: label_values(node_boot_time, instance) with regexp /(.):./

Thanks a lot