Plasmid-based short hairpin RNA against connective tissue growth factor attenuated monocrotaline-induced pulmonary vascular remodeling in rats.

Pulmonary hypertension is a life-threatening medical condition, and a growing body of evidence shows that the expression of connective tissue growth factor (CTGF) is significantly associated with its pathogenesis, making it an attractive therapeutic target. Our earlier work revealed that plasmid-based CTGF-specific short hairpin RNA (shRNA) could attenuate pulmonary artery smooth muscle cell (PASMC) proliferation and pulmonary vascular remodeling in rats exposed to cigarette smoke. In this study, we explored the therapeutic role of this shRNA plasmid in the treatment of monocrotaline-induced pulmonary vascular remodeling in rats, and demonstrated that the upregulation of CTGF in PASMCs following a single injection of monocrotaline could be attenuated by administration of the shRNA. Accordingly, this shRNA was found to repress monocrotaline-induced pulmonary vascular remodeling, as evidenced by its ability to reduce the percentage of muscularized vessels and the wall thickness of pulmonary vessels. We concluded that plasmid-based shRNA against CTGF attenuated pulmonary vascular remodeling in monocrotaline-treated rats. CTGF might be a potential target for the treatment of pulmonary vascular remodeling and pulmonary hypertension.

Current surgical interests in China.

Until recently, China had been isolated from Western countries for almost 30 years. Surgeons of Western countries, perhaps, are interested to know what is happening in surgery in China. This communication reviews the current interests in Chinese surgery. It is by no means complete, nor is that the intention. The intention is to introduce to our foreign colleagues a general overview of some highlights in Chinese surgery.

Postoperative fall in serum zinc concentrations unaffected by intravenous zinc therapy.

The serum zinc levels and urinary zinc outputs before and after a middle severity operative trauma were investigated. The serum zinc concentration dropped markedly 6 hr after operation in both supplemented and nonsupplemented groups. It gradually returned to near normal without exogenous supplies of zinc. Provision of therapeutic doses of zinc could not prevent the abrupt dip of the serum zinc level. The possible mechanism of such changes are discussed briefly.

Insulinoma: 31 years of tumor localization and excision.

This report is based on 31 years of experience with 116 cases of hyperinsulinism. Six cases had hypertrophy of the islets of Langerhans, 3 had widespead metastasis from malignant insulinomas, and 107 were benign adenoma cases. An immunoreactive insulin to glucose ratio of 0.3 of the peripheral venous blood before operation is of great value in diagnosing hyperinsulinism. Intraoperatively, immunoreactive insulin assay of the portal blood (IRI) is very valuable in determining if an insulinoma remains. The dividing line is 100 microU.ml-1. In localizing the tumor, "differential" PTPC is important before operation. During the operation, fine needle aspiration cytology may assist in ascertaining if the palpable tumor is an insulinoma. Multiple fine needle aspiration cytology examinations can sometimes reveal an insulinoma in an indurated pancreas. Portal vein blood IRI and blood sugar assays may serve to confirm if removal of the insulinoma is complete. Removal of the insulinoma controls hypoglycemia satisfactorily, but the brain damage incurred by prolonged hypoglycemia cannot be significantly altered. Removal of the tumor should be by enucleation, and the raw surface of the pancreas should be drained not sutured.

Evaluation of parenteral nutrition in the postoperative patient.

A variety of investigators have attempted to improve nitrogen balance during the postoperative period by modifying the composition of the infused nutrient solutions. This study compared the metabolic effects of administering standard amino acid solutions with a solution enriched with branched chain amino acids (BCAA). A prospective, randomized clinical study was performed in patients who had undergone subtotal gastrectomy or hemicolectomy, and subsequently cared for in the metabolic care unit. The patients were selected from specific entry criteria so that two groups of individuals were comparable. All patients underwent operation without complications. The plasma concentrations of valine and leucine were significantly increased (p less than 0.05 and p less than 0.01, respectively) two days after administration of solutions enriched with BCAA and throughout the entire postoperative period. The plasma glutamine concentrations tended to decrease in both groups; no concentration difference occurred between groups. Nitrogen balance tended to be more positive in the group receiving BCAA but there was no significant difference between groups after operation. Urinary excretion of 3-methylhistidine tended to increase postoperatively in both groups, but no difference occurred between groups. However, the urine excretion of isoleucine increased significantly in the patients receiving infusions enriched with BCAA. Both standard balanced amino acid and amino solutions enriched with BCAA were well tolerated in all patients.

Body composition in Chinese subjects: comparison with data from North America.

A multiple tracer dilution method measuring total body water, extracellular water, plasma volume, and red cell volume was used to study body composition. Healthy Chinese subjects were compared to a group of Chinese patients with various newly diagnosed gastrointestinal disorders scheduled for elective operation. Compositional data obtained from these groups showed no significant differences in compartmentalization, suggesting absence of major changes during the early stages of certain gastrointestinal diseases. In addition, healthy Chinese subjects were compared to a group of healthy Americans previously evaluated by similar dilutional methods. In males, body weight (kg) differed considerably (Chinese = 62.1 +/- 2.0 versus American = 72.5 +/- 4.1, p less than 0.02) and could be explained by alterations in body fat (Chinese = 12.4 +/- 1.3 versus American = 19.2 +/- 2.2, p less than 0.02) and extracellular water (Chinese = 14.4 +/- 0.5 versus American = 16.8 +/- 0.8, p less than 0.02). Functional tissue ("body cell mass") was similar in the 2 groups which suggested that Chinese have comparable body composition without an additional fat burden. The multiple tracer technique using deuterium oxide, sodium bromide, Evans dye, and Cr51 for body compositional assessment is accurate but expensive and laborious. Therefore, equally precise but more economical bedside methods are needed for routine compositional analysis.