Downloaded materials not showing in iTunes U

Hi everybody,

I'm having a strange behavior in iTunes. I try to download iTunesU matarials but when they are done (according to the downloading page) they still are grayed out in the iTunes U section with a button for download.

Second, unchecked pdf files are still synchronized in the book section to my iPad3 while they are iTunesU pdf's and should be shown only in that section and not in iBooks.

Any suggestions?

Thanks in advance.

Regards,

Adri