LONDON -- The FTSE 100 (INDEX: ^FTSE) has had a mixed week, pulled in various directions by European confusion and by the U.K.'s interim reporting season. As heads of the eurozone countries met, markets were expecting some concrete moves to address Spain's rising borrowing costs, but nothing firm was forthcoming.

But strengthening British blue-chip stocks, including banks, helped the index to a strong finish on Friday, and it ended the week up 160 points (2.8%) at 5,787 points.

Trinity Mirror (LSE: TNI.L)
Trinity Mirror soared by 39% this week, to 37.5 pence, after releasing interim results that showed adjusted operating profit up 11.5% to 52.5 million pounds and earnings per share up 23.7% to 14.6 pence.

The newspaper publisher has had a torrid time, losing 95% of its price since 2007 before this week's rise. But after dumping unpopular boss Sly Bailey in June, it looks like the recovery could be on.

Next (LSE: NXT.L)
High Street fashion chain Next gained 7.6% to end the week at 3,493 pence, after releasing a strong trading statement ahead of halftime figures. Although overall revenue was pretty much flat, online sales gained a nice 13%.

Full-year profit guidance has been lifted and is now expected to come in between 575 million and 620 million pounds ($895 million-$967 million). With the U.K.'s retail sector still struggling, that's pretty good, and it's helped to boost the price by 40% over the past 12 months.

Renold (LSE: RNO.L)
Renold lost 25% to 22 pence in the week as it released a profit warning. In May, the industrial chain and gear manufacturer had reported revenues up 9.6% with adjusted earnings per share more than doubled from 2 pence to 4.2 pence, though debt did rise.

But then on Aug. 2, we had an interim management statement telling us that deteriorating trading conditions are going to hit profits, which will now come in below previous expectations.

Spirent Communications (LSE: SPT.L)
Spirent Communications has been booming of late but saw its shares crash by 11% after its half-year results warned of weakening business in the second half of the year.

The first six months saw adjusted operating profit rise by 9% to $63 million (from $57.8 million for the first half of last year), and the dividend was increased by 10% to 1.39 cents per share, but the firm is expecting tough conditions in Europe to lead to "mid- to low single-digit" growth for the second half.

What now?
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