Colleagues of Madeleine McCann's father are to hold a vigil for the missing four-year-old today.

Dozens of members of the British Cardiovascular Society, who are meeting in Glasgow this week, are expected to gather this morning to express hope for the missing child's safe return.

The vigil will be held the day after a recorded appeal by Madeleine's parents, Kate and Gerry McCann, was aired on BBC1's Crimewatch in which they urged anyone with information on her whereabouts to come forward.

Madeleine's Glasgow-born father, a cardiologist based in Leicester, has received numerous messages of support from friends and colleagues in the medical profession.

His schoolfriend and former university colleague Dr Paul MacIntyre, who is based at the Royal Alexandra Hospital in Paisley, said 100 delegates would observe the vigil at Glasgow's Scottish Exhibition and Conference Centre this morning.

It will also be attended by Madeleine's aunt and uncle, as well as a Muslim Imam and a Catholic priest, who will say prayers for the missing child.

Dr MacIntyre, who has known Madeleine's father since he was 16, said: "The cardiology community recognises him as a colleague, and people who know Gerry want to make sure he knows that. We will be saying some words about hope that's the important message we want to send."

In the Crimewatch appeal the McCanns held up pyjamas like the one their eldest daughter was wearing when she disappeared on May 3 from the family's holiday apartment in the Algarve.

Mrs McCann spoke of her hope that her daughter has not been harmed, saying: "The majority of people are really good people and I think that's been demonstrated by all the fantastic support we've had.

"There are a few bad people in the world but also there are a few sad people and I guess I'm hoping that it's some- one sad who just wanted our daughter."

Mr McCann, 39, gave a detailed description of a suspect seen carrying what was thought to be a child near the holiday complex in Praia da Luz on the night Madeleine disappeared.

Back in Portugal yesterday the McCanns set off on the next stage of their European search for Madeleine after a long-awaited briefing with Portuguese police which a family spokesman said did not reveal any significant breakthroughs.

Mr and Mrs McCann flew to Germany by private jet to publicise their campaign to find their daughter.

They will meet German Deputy Interior Minister Wolfgang Schauble and the mayor of Berlin, Klaus Wowereit, before heading to Amsterdam where the couple lived for a year.

Meanwhile, it emerged yesterday a 33-year-old woman has been arrested on suspicion of making bogus door-to-door collections for the fund set up to help find Madeleine.

Staffordshire Police said the woman, from Chadsmoor, Cannock, was detained on Friday after being given cash by householders in the town. She has been bailed until June 30.