TranS1 Inc. (TSON) announced that it expects revenue to be roughly in the range of $7.9 million to $8.0 million in the second quarter of this year, lower than its previous guidance of $8.7 million to $9.0 million but approximately 33% higher than the revenue in the year-ago quarter.   TranS1 believes that its revenue is likely to be affected by the reimbursement uncertainty surrounding its AxiaLIF procedure. The company expects to release its second quarter results on July 30, 2009, after the close.   TranS1 is engaged in designing, developing and marketing minimally invasive products that utilize its proprietary TranS1 surgical approach to treat degenerative disc disease affecting the lower lumbar region of the spine.   TranS1 is badly hurt by a reimbursement uncertainty surrounding its AxiaLIF procedure. We believe expected near-term reimbursement changes would make the pre-certification and administration process time-consuming and could create some revenue ...