大鼠肝抑素纯化及其生物活性的检测

用ＳｅｐｈａｄｅｃＧ－５凝胶过滤层析法，进一步纯化具肝抑素生物活性的大鼠肝蛋白质粗提品，以分离的大鼠再生肝的肝细胞为靶细胞，体外检测各洗脱峰浓缩物对肝细胞增殖的制率结果证明，Ｅ峰浓缩物的抑制作用最强，其活性比为粗提品的２０倍，ＳＤＳ聚丙烯酰胺电泳图及蛋白质迁移率测定表明，该浓缩物的主要成分为分子量１３．５ｋＤ的多肽。本研究对大鼠肝抑素做了初步纯化，验证了该物质在肝再生中起重要调控作用的生物效应。     

Allograft rejection results from a failed attempt by the immune system to protect foreign tissue

The focus of our research is to understand the immune response to foreign tissue. We believe that adichotomy exists within the immune response to an allograft such that part of the response is dedicated to the protection of the graft. Nevertheless, in a dominantly graft-aggressive environment, rejection typically ensues. In this article, we describe models that have been set up to test directly the ability of potentially protective aspects of the immune response to prevent allograft rejection. We discussour data in the context of a growing body of exciting and often controversial literature.     

Post-exercise ketosis and the glycogen content of liver and muscle in rats on a high carbohydrate diet

Summary Post-exercise ketosis is known to be suppressed by physical training and by a high carbohydrate diet. As a result it has often been presumed, but not proven, that the development of post-exercise ketosis is closely related to the glycogen content of the liver. We therefore studied the effect of 1 h of treadmill running on the blood 3-hydroxybutyrate and liver and muscle glycogen concentrations of carbohydrate-loaded trained (n=72) and untrained rats (n=72). Resting liver and muscle glycogen levels were 25%–30% higher in the trained than in the untrained animals. The resting 3-hydroxybutyrate concentrations of both groups of rats were very low: <0.08 mmol·1⁻¹. Exercise did not significantly influence the blood 3-hydroxybutyrate concentrations of trained rats, but caused a marked post-exercise ketosis (1.40±0.40 mmol·1⁻¹ 1 h after exercise) in the untrained animals, the time-course of which was the approximate inverse of the changes in liver glycogen concentration. Interpreting the results in the light of similar data obtained after a normal and low carbohydrate diet it has been concluded that trained animals probably owe their relative resistance to post-exercise ketosis to their higher liver glycogen concentrations as well as to greater peripheral stores of mobilizable carbohydrate.     

Clinical characteristics of renal transplant recipients that underwent urologic surgery for de novo disease before and after transplantation

The pre-transplantation goal of the urologist is the optimization of urinary tract condition. Therefore, urologic surgery may be needed before or after renal transplantation. We analyzed the results of urologic surgery performed because of de novo urologic diseases. Between January 1986 and January 2001, 281 patients underwent renal transplantation, and 23 urologic surgical procedures were performed on 21 transplant recipients before or after renal transplantation because of de novo urologic diseases. By review the major reasons for urologic surgery in recipients were polycystic kidney diseases, vesicoureteral reflux, and dysfunctional voiding disorders. Nineteen surgical corrective procedures were done average 2.9 months before transplantation. The mortality rate was 10.5%. Four patients underwent urologic surgery at an average 57.5 months after transplantation. We highlight the fact that patients with uremia are vulnerable to surgical complications, and conclude that more intensive longterm urologic follow-ups should be conducted on recipients.     

Spontaneous reanastomosis between lymphatic vessels following syngeneic transplantation of the small intestine in the rat

Abstract Spontaneous lymphvascular reanastomosis (SLR) following small bowel transplantation in rats is of clinical relevance for the resorption of long chain fatty acids. Detailed morphological and molecular data concerning the process of lymphvascular reanastomosis are not available in the literature. In this study SLR was investigated using microradiology and scanning electron microscopy. Between the 8^th and 21^st postoperative days following transplantation SLR does not occur between the intestinal trunk of the transplant and the thoracic duct of the recipient. Instead, an indirect connection was observed between the inserted advential lymphatic vessels of the mesenteric artery and lymphatic vessels of the aorta or ductus deferens, which are connected with the thoracic duct.     

Fine-needle aspiration biopsy of hepatic papillary cystadenocarcinoma in Caroli's disease.

A case of papillary adenocarcinoma arising in Caroli's disease (CD) in a 25-yr-old woman is reported. The diagnosis of malignancy was made by ultrasound-guided, fine-needle aspiration biopsy (FNAB). As there were no metastasis, a liver transplant was performed and the diagnosis was histologically confirmed. Only 22 cases of malignant transformation of CD have been reported to date, all among middle-aged subjects (mean age: 52 yr) of both sexes. Most of these reported cases (83%) were found to be bile duct adenocarcinomas with occasional reports of hepatocellular and undifferentiated carcinomas. Our case is the youngest reported to date and the first to be diagnosed cytologically.     

Increasing transplant mass results in long-term allograft survival and recovery from transplant vasculopathy

Late allograft rejection due to transplant vasculopathy continues to be a major clinical problem. Increasing the ratio of donor transplant size to recipient weight has been shown to reduce the incidence of late allograft failure. Using a murine pancreas transplant model we have tested the hypothesis that increasing the donor transplant size in a recipient can promote long-term allograft survival by promoting recovery from transplant vasculopathy. Recipients of an allograft that showed extensive vasculopathy were transplanted with a second donor transplant. The effect of the second allograft on the vasculopathy present in the first graft was measured. Transplanting a second allograft reversed all signs of ongoing rejection, including transplant vasculopathy, resulting in long-term survival of the first graft. Vasculopathy was only reversed if the first and second grafts were from the same mouse strain, suggesting an antigen-specific mechanism. However, the recovery of the first graft was not associated with antigen-specific peripheral tolerance.     

Early detection of metastasis by alterations in the cellular immune system in the murine liver and blood

We investigated the reaction of the cellular immune system of liver and blood in the C57BL/6 mouse to a metastasizing Lewis lung carcinoma. The cellular immune system of the liver consists of mature and immature macrophages, B-cells, T-cells including their subpopulations, and natural killer cells, and their percentage frequencies differ significantly from those in the corresponding mononuclear blood cell (MBC) compartment. This suggests that the hepatic immune cells represent a system with autonomous function showing a typical homing of its members. Imminent metastasis to the liver is signalled by impressive alterations in the percentage frequencies of nonparenchymal liver cells (NPLC). There are a dramatic loss of mature macrophages, an increase in immature macrophages, a reduction of T-helper cells leading to a low CD4/CD8 ratio, and an increase in natural killer cells. In the blood, the corresponding precursor cells show comparable changes with a delay of at least 2 days. Early metastasis is accompanied by a significant increase in mononuclear NPLC producing tumour necrosis factor . The alterations in percentage frequencies of the NPLC during tumour metastasis differ markedly from the changes in these cells in the liver during endotoxinaemia.     

Celiac vagotomy attenuates the ingestive responses to epinephrine and hypertonic saline but not insulin, 2-deoxy-D-glucose, or polyethylene glycol

The ingestive responses of rats given celiac vagotomy (C), combined celiac and hepatic vagotomy (CH), or low total vagotomy (removal of all tissue from around the esophagus, stomach and duodenum; LT) were compared with sham operated controls (S) in a series of regulatory challenges. The vagotomized groups responded normally to 2-deoxy-D-glucose (2DG; 125, 250, 500 mg/kg, IP), insulin (4, 8, 12 U/kg, IP), and polyethylene glycol (10 ml/kg: 30% w/v, SC), but displayed attenuated responses to epinephrine (40, 80, 120 micrograms/kg, IP) and hypertonic saline (10 ml/kg: 0.25, 0.5, 1.0 M, IP). These results can be interpreted as evidence that the celiac vagus carries a major component of hepatic afferent innervation. Additionally, when considered with other findings they suggest that whereas the anorectic activity of epinephrine is mostly confined to the liver, 2DG hyperphagia involves stimulation of a wider population of peripheral metabolic receptors.     

Hepatic reinnervation following orthotopic liver transplantation in man.

We have studied changes in the pattern of intrinsic hepatic innervation in sequential liver biopsies from 16 patients who underwent orthotopic liver transplantation. Seventy-one needle biopsies were used, including specimens obtained at the time of transplantation (time zero) and up to 4 years post-transplantation; five transplant hepatectomy tissue blocks removed 3-32 months after transplantation were also assessed. Paraffin sections were immunostained with anti-PGP 9.5 and anti-S-100 to identify nerve fibres. All 'time zero' biopsies contained portal nerves and all but two showed staining of parenchymal fibres. After 1 week, no subsequent biopsies contained parenchymal fibres. The disappearance of portal fibres was less rapid and showed greater variability between patients, but they had all disappeared by 6 weeks and there was no positive staining between 6 and 60 weeks. Thereafter, a minority of biopsies showed innervation of a few small portal tracts. Samples from the porta hepatis, hepatectomy specimens, and needle biopsies containing large tracts showed persistence of major nerve trunks at all stages. Abnormally large nerve bundles were seen in some of these areas. The pattern of nerve staining showed no obvious relationship to the intensity of rejection changes. Our results suggest that there is a limited, delayed capacity for regeneration of portal, but not parenchymal, fibres in the transplanted human liver. The physiological significance of this long-term parenchymal denervation in transplanted livers remains to be determined.