Randomized controlled trial of laparoscopic transabdominal preperitoneal hernioplasty vs Shouldice repair.

BACKGROUND: There is a scarcity of data on long-term results after laparoscopic hernia repair. Herein we report on the outcome of a group of patients who were followed up for 5 years in a multicenter study on hernia repair. METHODS: A total of 100 patients with 127 hernias were randomized to undergo either transabdominal preperitoneal (TAPP) or Shouldice hernia repair. Follow-up was by clinical examination and standardized questionnaire. RESULTS: Of the 100 patients who underwent surgery, 84 were available for follow-up at 5 years. The TAPP procedure was less painful than the Shouldice repair, with fewer patients receiving narcotic analgesics. The median time to return to 100% activity was shorter in the laparoscopic group (21 days) than in the Shouldice group (40 days). Up to 60 months after the operation, the complication rate was lower in laparoscopically repaired hernias (19/66) than in the open group (25/61). There were two recurrences (3.9%) in the TAPP group and five in the Shouldice group (10.2%). CONCLUSION: The TAPP hernia repair yields comparable or better results than Shouldice herniorrhaphy in terms of postoperative pain, recovery, and recurrence rate.

C4 Gene Expression in Photosynthetic and Nonphotosynthetic Leaf Regions of Amaranthus tricolor.

Throughout most of its growth and development, Amaranthus tricolor produces fully green leaves. However, near the onset of flowering, unique leaves emerge that consist of three distinct color regions: green apices, yellow middle regions, and red basal regions. The green apices are identical to fully green leaves in terms of pigment composition, photosynthetic function, and C4 gene expression. The yellow and red regions possess greatly reduced levels of chlorophyll and they lack photosynthetic activity. The absence of photosynthetic capacity in the nongreen leaf regions was associated with three distinct alterations in C4 gene expression. First, there was a reduction in the translation of C4 polypeptides, and in the yellow regions synthesis of the ribulose-1,5-bisphosphate carboxylase small subunit occurred in the absence of large subunit synthesis. Second, there was a reduction in the relative transcription rates of two plastid-encoded photosynthetic genes, rbcL and psbA. Third, there was a loss of bundle-sheath cell-specific accumulation of the rbcL and RbcS mRNAs (but not the polypeptides, which remained bundle-sheath-specific). This study indicates that alterations in photosynthetic activity or developmental processes responsible for the loss of activity can influence C4 gene expression at multiple regulatory levels.

Post-transcriptional control of cell type-specific gene expression in bundle sheath and mesophyll chloroplasts of Amaranthus hypochondriacus.

Plants that utilize the highly efficient C4 photosynthetic pathway possess two types of specialized leaf cells, the mesophyll and bundle sheath. In mature leaves of amaranth, a dicotyledonous C4 plant, ribulose 1,5-bisphosphate carboxylase (Rubisco) is localized specifically to the chloroplasts of bundle sheath cells, and is not present in the chloroplasts of mesophyll cells. The cell type-specific expression of the chloroplast-encoded Rubisco large subunit (rbcL) gene, and other representative chloroplastic genes, was investigated by using separated bundle sheath and mesophyll chloroplasts prepared from mature amaranth leaves. One-dimensional SDS-polyacrylamide gel electrophoresis revealed several differences in the polypeptide compositions of the two chloroplast types. Western analysis demonstrated that, as in the intact leaves, the Rubisco LSU polypeptide was present only in chloroplast preparations from bundle sheath cells. Pyruvate orthophosphate dikinase (PPdK), a nuclear-encoded chloroplastic enzyme, was found only in the mesophyll chloroplast preparations. rbcL mRNA was present only in the bundle sheath chloroplast preparations, whereas transcripts for the chloroplast-encoded psbA, psaA-B, and rpl2 genes were present in both chloroplast types. Although the rbcL message accumulated only in bundle sheath chloroplasts, run-on transcription analysis indicated that the rbcL gene was transcribed in both bundle sheath and mesophyll chloroplast preparations. Therefore, differential rbcL gene expression in the isolated C4 chloroplasts is regulated, at least in part, at the post-transcriptional level. Possibly this control is mediated by differential processing or stabilization of the rbcL transcript.