Oil jumped and US equity-index futures retreated as traders turned cautious following a weekend flare-up in US-Iran tensions, curbing optimism that strains in the Middle East were easing. Oil jumped and US equity-index futures retreated as traders turned cautious following a weekend flare-up in US-Iran tensions, curbing optimism that strains in the Middle East were easing. Brent rose 5.7% to $95.50 per barrel after the US Navy seized ... [366 chars]