Ups... the query
SELECT n.id,
                        date_format(n.adt, '%d-%m-%Y') AS adt,
                        n.title,
                        n.introduction
                    FROM tyskielwy_news n, tyskielwy_news_hierarchy_news nhn
                    WHERE n.id = nhn.news_id AND nhn.news_hierarchy_id = 1 AND n.is_active = 1
                    ORDER BY n.adt DESC limit 350, 10
caused some trouble...
MySQL server has gone away