Rapid response of hepatocyte growth factor in pulmonary ischemia in a rat model.

Hepatocyte growth factor (HGF) is a multifunctional factor implicated in tissue regeneration, wound healing, and angiogenesis. HGF was initially thought to be liver-specific, but it has become clear that HGF acts on alveolar type II cells and bronchial epithelial cells. This study was conducted to determine the role of HGF in pulmonary ischemia in a rat model. The first increase of the plasma HGF level was noted 30 min after pulmonary ischemia, and reached a peak at 12 h. Real-time reverse transcription polymerase chain reaction (Real-time RT-PCR) revealed that the HGF messenger RNA (mRNA) expression in the injured left lung was markedly increased at 1, 6, and 12 h after pulmonary ischemia (P &#60; 0.05). The interleukin-1beta (IL-1beta) mRNA expression, one of the inflammatory cytokines which induces HGF expression, was markedly increased at 1 h in the injured left lung (P = 0.0007). Therefore, we considered that HGF might be mainly induced by paracrine mechanisms in pulmonary ischemia. In conclusion, we have shown that the expression of HGF was induced in pulmonary ischemia, and may be a useful biological marker for the early diagnosis.</p

Utility of vessel-sealing systems in thyroid surgery.

The LigaSure TM vessel-sealing system (VSS) represents a new approach to intraoperative ligation. This clinical study retrospectively examined the utility of the VSS in thyroid surgery. In this study, we analyzed 56 consecutive patients who underwent thyroid surgery. Characteristics such as operative duration, the volume of intraoperative hemorrhage, and postoperative course were analyzed and compared between thyroid surgery using the VSS or conventional handtie methods. The present results indicate no significant differences in operative duration, volume of intraoperative hemorrhage, postoperative course, or duration of postoperative drainage between surgeries using the VSS or conventional methods. However, the postoperative hospital stay was found to be significantly shorter (p&#60;0.05) with the VSS. No serious postoperative complications were encountered, and no significant differences were observed in the frequency of postoperative complications between methods. The VSS may simplify procedures for thyroid surgery, and hemostasis is effective for both thyroid vessels and thyroid parenchyma. However, further evaluation is warranted to adequately determine the relative merits of the VSS compared to conventional handtie methods.</p

An experimental study on pumpless extracorporeal membrane oxygenation (ECMO) support in a canine model.

This study was carried out to determine whether an extracorporeal membrane oxygenation (ECMO) support could be sufficiently conducted by the right ventricle alone from the viewpoint of the hemodynamics and blood gas state. Six infant dogs underwent a bypass between the left pulmonary artery and left atrium with an in-line oxygenator after a left pneumonectomy. Partial ECMO support was conducted simply by opening the circuit, and total ECMO support was conducted by ligating the right pulmonary artery. After the establishment of partial ECMO, approximately one-third of the right ventricular output was passively shunted through the bypass circuit, and the cardiac index and central venous pressure did not change. The mean pulmonary arterial pressures increased significantly. After a complete ligation of the right pulmonary artery, all 6 dogs survived for 12 h, but the cardiac output and blood pressure decreased significantly. The blood gas state was sufficiently maintained throughout the experiment. The results suggest the possibility of using the pumpless ECMO support. However, the flow resistance of the membrane oxygenator proved to still be too high for use in a total pumpless ECMO. Further studies on long-term ECMO and the development of a membrane oxygenator with a considerably low flow-resistance are needed.</p