'Imperial Leather' soap maker PZ Cussons was the biggest faller after it warned that overall profit in the six months to the end of November will come in below expectations.The firm said high raw material costs and adverse exchange rate movement had continued to impact margins in the first half of the year. It has also been hit by severe weather in Thailand and social unrest in the Middle East.Thomas Cook also fell, hit by news that it is to be downgraded from the FTSE 250 to the FTSE Small Caps index. This is also true for Mothercare and Premier Foods. London & Stamford Property followed suit after it was revealed that General Electric Pension Trust has completed the sale of its ordinary shares in the firm. Micro Focus fell back, following yesterday's impressive gains on the back of its first-half figures.Meanwhile, Ashtead, the plant hire group, was in the top spot after saying it expects full-year profits to be "substantially ahead" of expectations after seeing its underlying pre-tax profit soar nearly 200% for the first half ended 31 October.The firm, which generated underlying revenues of £575.5m, up 24% on the same period the previous year, made a pre-tax profit of £84.4m, compared to £30m the year before, marking a 197% increase. Scottish soft drinks maker AG Barr was still performing well after it was boosted by yesterday's statement which said current trading remains in line with company expectations and it is on track for the full year despite constrained consumer spending and fierce competition. FTSE 250 - RisersAshtead Group (AHT) 210.00p +12.90%Kenmare Resources (KMR) 38.38p +7.48%AG Barr (BAG) 1,218.00p +2.78%Pace (PIC) 70.90p +2.53%AZ Electronic Materials SA (WI) (AZEM) 241.80p +2.46%African Barrick Gold (ABG) 520.50p +2.26%Jupiter Fund Management (JUP) 223.30p +2.20%Kentz Corporation Ltd. (KENZ) 480.00p +2.13%QinetiQ Group (QQ.) 131.00p +2.02%BTG (BGC) 305.70p +1.90%FTSE 250 - FallersPZ Cussons (PZC) 309.40p -10.24%Thomas Cook Group (TCG) 15.00p -8.48%Sports Direct International (SPD) 209.40p -8.00%London & Stamford Property Ltd. (LSP) 106.30p -7.73%Mothercare (MTC) 153.10p -6.36%Micro Focus International Plc (MCRO) 380.80p -5.53%SIG (SHI) 79.15p -5.49%Ferrexpo (FXPO) 283.70p -5.43%Gem Diamonds Ltd. (DI) (GEMD) 190.00p -5.24%Northgate (NTG) 218.90p -5.24%NR