摘要:

Hypertonic/hyperoncotic solutions (e.g. HHS: 7.2 % NaCl/10% dextran-60) are highly effective to normalize cardiovascular function in hemorrhagic shock due to rapid mobilization of fluid from the extravascular compartment. Since experiences are limited with regard to potential side effects of this treatment on the central nervous system, the present studies were carried out under particular consideration of the cerebral blood flow and O2 supply. HHS was administered in albino rabbits subjected to α-chloralose anesthesia and artificial ventilation with and without hemorrhagic hypovolemia. Hemorrhagic hypovolemia of 30 min duration was induced by withdrawal of approximately one third of the circulating blood volume resulting in a decrease in arterial blood pressure to 40 mm Hg. HHS was studied in addition in normovolemic animals. Cardiac output was rapidly normalized by infusion of HHS in animals with hypovolemia, while it increased intermittently in normovolemic animals. In animals with hemorrhagic shock arterial blood pressure recovered by treatment to approximately 70% of normal, whereas blood pressure remained unchanged after infusion of HHS in normovolemic controls. Cerebral blood flow, which was assessed by H2 clearance at the brain surface, had a range of 43.0–50.3 ml/100 g/min under control conditions. It remained virtually unchanged during hemorrhagic hypovolemia and also after infusion of HHS in normovolemic animals. Treatment of shock by HHS was followed 90 or 120 min later by a moderate increase in regional cerebral blood flow to 61 ml/100 g/min. Local tissue PO2 at the brain surface was obtained by an O2 multiwire electrode in the vicinity of the H2 clearance measurements using a weightless suspension system to avoid compression of the brain surface. Infusion of HHS in normovolemic animals did not affect the O2 supply of the brain. Hemorrhagic hypovolemia which led to a left shift of the cerebral PO2, histogram was followed by gradual normalization after fluid resuscitation. The current findings taken together do not indicate adverse side effects of this efficient method of fluid resuscitation with regard to the cerebral blood and O2 supply. The results make worthwhile further investigations on HHS in the presence of a focal brain lesion causing brain edema to find out whether the HHS are useful also for the treatment of intracranial hypertensi

ISSN:0014-312X    

DOI:10.1159/000129183

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

Tissue storage of hydroxyethyl starch (HES), a widely used artificial colloid, has been reported. In order to clarify whether storage of HES can be detected in tissues by immunohistochemical methods, use was made of a polyclonal rabbit anti-HES antiserum. Thirteen days after a single intravenous injection of HES rats were sacrificed and liver, spleen, lymph node, lung, kidney and skin were removed. On paraffin sections in all organs the anti-HES antiserum stained mainly cells which could be attributed to the mononuclear phagocyte system, as confirmed by the use of the antimacrophage monoclonal antibody ED 1. The use of a polyclonal anti-HES antiserum may allow analysis of long-term storage and possible side effects in various tissues of man.

ISSN:0014-312X    

DOI:10.1159/000129184

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

Acute pancreatitis is characterized morphologically by edema, hemorrhages, parenchymal necrosis and fat necrosis. The inflammation is accompanied by infiltration of polymorpho-nuclear leukocytes. According to the absence or presence of necrosis the disease can be divided into interstitial (or edematous) pancreatitis and hemorrhagic-necrotizing pancreatitis. The severity of disease can be graded in the histological sections either by giving scores to the different types of morphological alterations or by determining the proportion of necrotic tissue of the total lobular parenchyma. The former method is based on subjective assessment of histological slides and is suitable for the evaluation of both edematous and necrotizing pancreatitis. Histometric measurement of necrotic parenchyma can be used only in the necrotizing forms of experimental pancreatitis, e.g. in those induced by intra-ductal injection of bile, bile salts or digestive enzymes, and in the dietary ethionine-induced pancreatitis. Grading of the tissue damage is essential when the effects of different therapies are evaluated.

ISSN:0014-312X    

DOI:10.1159/000129235

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The present study deals with the morphological and functional development of intraomentally and subcutaneously implanted splenic tissue. Spleens and splenic transplants from 138 Lewis rats were investigated with immunohistological, immunological and molecular biological methods at different times after operation (up to 200 days postoperatively). The analysis of the development revealed a nonsignificant reduction concerning the weight of subcutaneous replants and a nonsignificant decrease of the weight of female transplants of both groups at different phases after operation. The cell composition of cell suspensions from spleen and both transplant types showed a deficiency of T, B, MHC-L cells and a certain macrophage subset (ED-3+ cells) in transplants. In a quantitative immunohistological analysis of compartments (red pulp, periarteriolar lymphoid sheaths, marginal zone and follicles) the T cell reduction was related to the Tsupp/cyt cells and T cell receptor bearing cells in the periarteriolar lymphoid sheaths, whereas the density of T helper cells was normal. In addition, a different homing of K-light chain positive and leukocyte common antigen (B cell type)-positive B cells in follicles and marginal zone was detected. The amount of two macrophage subsets (ED-1+ and ED-2+ cells) was increased in the red pulp. Only minor differences in the immunoarchitecture of transplants at different implantation sites were measured. A functional analysis of spleen compared to both transplant groups elicited a B cell defect after LPS stimulation in subcutaneous transplants and a reduced allogeneic response of both transplant types but a normal proliferation of T cells after ConA stimulation and a correct IgM antibody response against sheep red blood cells. The in vivo mRNA expression and the expression kinetics of interferon-γ and granulocyte-macrophage colony-stimulating factor after antigen stimulation differed in both transplant groups with a remarkable permanent expression of both mediators in subcutaneous transplants. It can be summarized that the results clearly indicate a development of spleen-like immunoarchitecture of intraomental replants with subtle cellular, functional and molecular alterations. In contrast, despite a comparable development, some severe functional defects occurred in subcutaneous implants pointing out the important role of interactions between the regenerating splenic tissue and the target tissue on a functional and molecular level

ISSN:0014-312X    

DOI:10.1159/000129185

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The closed duodenal loop (CDL) technique, one of the first experimental models producing experimental acute pancreatitis, is described in this article. Since this model was published first by Pfeffer in 1957, it has undergone several modifications. The CDL method is an easily practicable and reproducible model to investigate acute hemorrhagic pancreatitis. In view of other available experimental models, the CDL technique has lessened in popularity.

ISSN:0014-312X    

DOI:10.1159/000129236

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

Intravenous infusion of the synthetic cholecystokinin analogue cerulein at a dose of 0.25 µg/kg/h causes maximal stimulation of pancreatic exocrine secretion. The infusion of supra-maximal doses of cerulein (5 and 10 µg/kg/h) induces a significant increase in pancreatic enzymes in blood, and interstitial edema and inflammatory cell infiltration. This model of hormone-induced pancreatitis works in rats, mice, dogs and hamsters. Besides intravenous infusion, repeated intraperitoneal injections can also be used for induction of pancreatitis. In the early phase of cerulein-induced pancreatitis, large autophagic vacuoles result from fusion of zymogen granules within the acinar cell. This is accompanied by an increase in lysosomal enzyme activity and activation of trypsinogen which finally leads to cellular necrosis. All animals survive the induction of pancreatitis. The pancreas completely regenerates within 6 days after induction of pancreatitis. This model of experimental pancreatitis favors the analysis of intracellular events in the early phase of pancreatiti

ISSN:0014-312X    

DOI:10.1159/000129237

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

Pathologic and immunohistochemical studies of 13 patients with mucinous cystic neoplasm of the pancreas were performed in order to determine whether these lesions represent overt or latent malignancy. In 9 patients with mucinous cyst-adenoma, the foci of mucus-rich columnar epithelia formed the usual pattern of stratifications and papillary projections with a benign appearance and did not stain with mouse monoclonal antibody to CEA (CM-010, Mochida, Japan). In contrast, the foci of mucus-poor columnar epithelia which were in a focal distribution showed moderate to severe atypical hyperplasia and reacted strongly with anti-CEA in 6 of the 9 patients. In addition, areas of both noninvasive and invasive mucinous cystadenocarcinomas in 4 patients, which were composed primarily of mucus-poor columnar epithelia, showed diffuse cytoplasmic and/or apical reactivity with anti-CEA. Based on these results, we conclude that severe atypical epithelial hyperplasia composed primarily of mucus-poor columnar epithelia represents a precursor to mucinous cystadenocarcinoma, and, therefore, mucus-poor atypical epithelia may undergo malignant transformation.

ISSN:0014-312X    

DOI:10.1159/000129186

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The present work evaluates the methodology and standards of acute hemorrhagic-necrotizing pancreatitis induced by feeding a choline-deficient, ethionine-supplemented (CDE) diet to mice. The diet model appears to be a good approximation of severe necrotizing human pancreatitis. Both the gross and histological appearance of the pancreatic and peripancreatic inflammation as well as the clinical and biochemical course of diet-induced pancreatitis resemble human disease. By limiting the period of feeding the diet, one can control the mortality at any desired level between 0 and 100%. Ascites, acidosis, hypoxia and hypovolemia occur in this model as well as in human pancreatitis. The time course of the morphological and biochemical alterations have extensively been studied and are, thus, well defined in this model. Despite the differences in pathogenesis of pancreatitis induced in this model versus human disease, the experimental pancreatitis and clinical pancreatitis share several pathophysiologic features. Therefore, the model is suitable to study pathophysiologic aspects of this disease. The diet model is particularly well suitable to study the potential for new therapeutic substances. The small size of the animals used, however, is a limitation for the evaluation of surgical procedures and of new diagnostic tools. Several pitfalls and problems have to be considered in order to obtain valuable data. The amount of injury produced by the CDE diet depends critically on sex, age and weight of the mice. Special care has to be taken to guarantee that the intake of the CDE diet is identical between different experimental groups. Therefore, each set of experiments needs to include a separate control group of mice which receive the CDE diet without any other special treatment. The potential benefit of an experimental therapy can be assessed by measuring survival, various biochemical and histological features, and alterations in hematocrit, pH and blood gases.

ISSN:0014-312X    

DOI:10.1159/000129238

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

Sepsis may initiate acute respiratory distress syndrome which may be accompanied by an increased pulmonary epithelial-endothelial permeability. In this study, sepsis was induced by an intraperitoneal implantation of gelatine capsules containing Escherichia coli/Bacteroides fragilis adjuvant substance. The importance of bacteria in sepsis-related lung injury was studied in rats given an intraperitoneal injection of E. coli or in rats given the adjuvant substance alone in capsules intraperitoneally. Rats with empty capsules were used as controls. The rats were intratracheally instilled with bovine serum albumin (BSA) directly after the capsule implantation or the injection of E. coli, and the passage over the lower respiratory tract was assessed as blood plasma levels of immunoreactive BSA. The plasma BSA levels in the control rats increased continuously up to 24 h after intratracheal instillation. This increase was significantly augmented already 1 h after the septic challenge, i.e. before any clinical symptoms were observed, in both the septic rats and the rats with the E. coli injected intraperitoneally. Furthermore, the time required to obtain maximal plasma BSA levels was shorter in septic, adjuvant-exposed and in E. coli-injected rats than in the controls. The plasma levels and the total BSA passage over the lower respiratory tract was significantly higher (p < 0.001) in the septic and in the E. coli’-injected rats than in the adjuvant-exposed and the control rats. The results indicate that macromolecules pass over the lower respiratory tract into the blood circulation in higher amounts in septic than in control rats and rats exposed only to adjuvant substance already before any clinical signs of sepsis are observed, and that this effect may be due to bacteria and/or bacterial products. This increased inward passage may reflect the early damage to the epithelial-endothelial barrier of the respiratory tract in sepsi

ISSN:0014-312X    

DOI:10.1159/000129187

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

We compared the tissue response to the intraperitoneal implantation of three different prostheses (Gore-Tex®, Mersilène®, Vicryl-Mersilène) used to repair abdominal wall defects in rats. Vicryl-Mersilène is a new experimental prosthesis made of Dacron (Mersilène) coated with absorbable polyglactin (Vicryl®). The least amount of adhesions to omentum and gut was found with Mersilène. Gore-Tex was responsible for the accumulation of neutrophils rather than macrophages mostly collected in close contact with Mersilène and Vicryl-Mersilène. Fibrosis, evaluated by histology and computerized morphometry, was mostly found with Vicryl-Mersilène. This should allow a better incorporation of Mersilène and a tighter anchorage to the abdominal wall, after Vicryl

ISSN:0014-312X    

DOI:10.1159/000129188

出版商:S. Karger AG    

年代:1992

数据来源: Karger