Biomedical subjects
Publications and source records attributed to C Ruchti.
A case of a follicular tumor in the sellar region is described without evidence of a primary tumor within the thyroid gland or at a site known to harbor ectopic thyroid tissue. Large amounts of thyroglobulin were readily demonstrated mainly within the colloid of the follicles. The possible development from heterotopic thyroid tissue at this unusual site is discussed.
A large animal model for substitutive pancreaticosplenic composite transplantation with urinary drainage to the bladder has been developed in the pig. Transplantations were performed in 7 nontissue-typed donor-recipient combinations without immunosuppressive medication. Six recipients showed perfect graft function at least until the 5th postoperative day. Blood glucose, intravenous glucose tolerance tests and urine amylase concentrations proved to be sensitive markers of graft function. Scintigraphic follow-up examination with 99mTc tin colloid could only record perfusion of the splenic transplantation. With this model the role of the spleen in pancreaticosplenic composite transplantations can be studied in forthcoming experiments.
Two cases which presented with acute massive lower gastrointestinal hemorrhage from jejunal diverticulosis are reported. The various clinical presentations of this rare disease are discussed. The life-threatening complication of massive bleeding is specially outlined. The cases reported in the literature resemble the Dieulafoy ulcer lesion of the stomach.
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Verrucous carcinoma of the esophagus is a rare variant of squamous cell carcinoma with a slow, non-invasive growth without formation of metastases. Until today, only 8 cases of verrucous carcinoma of the esophagus have been reported in the literature. All of these tumours showed infiltration of adjacent mediastinal structures or even lymph node metastases. In therefore seems doubtful, wether these tumours were really verrucous carcinomas rather than squamous cell carcinomas of the papillary type. Several authors have questioned the malignant nature of these tumors recently. We report a case of a verrucous lesion of the esophagus the course of which we were able to observe over a period of several years. Transhiatal esophagectomy without thoracotomy is recommended as treatment of choice for verrucous tumours of the esophagus.
Based on autopsy findings in 301 adults who had died after intensive care, different patterns of single or multiple organ damage were identified. Signs of septicemia and/or exudative-to-fibrosing alveolitis (EFA) of the lungs, the prominent cause of the adult respiratory distress syndrome (ARDS), were recognized in 89 cases. Severe, progressive EFA, which appears to ensue mainly from continuing damage to alveolar walls, consequent fibroblast proliferation and so-called atelectatic induration (collapsed alveoli forming single thick septa), was registered only in individuals who had undergone long-term intensive care. The latter was necessitated in various severe conditions of which abdominal disease was the most important. Systemic disorders, such as hemorrhagic diathesis and multiple organ damage ("multiple organ failure"), showed a close correlation with septicemia. Infections with gram-negative bacteria appear to play a special role in such processes. Morphologically, these cases were characterized by multiple organ/system damage, e.g., in order of frequency, partial necrosis of renal proximal tubules, followed by signs of regeneration; jaundice; splenitis; lobular pneumonia; centrolobular-to-zonal liver necrosis, in part combined with cholestasis; petechial and/or extended hemorrhage; and others. This complex pattern contrasted strongly with findings in individuals who had been admitted to intensive care because of e.g. a cardiovascular incident: in this latter group (125 cases) intensive care was usually of short duration, progressive EFA was largely absent, signs of septicemia were exceptional, and multiple organ/system damage was rare. The group with polytraumatism (28 cases) exhibited a pattern of organ damage intermediate between (a) and (b).
Early postoperative CT scans of three patients who had undergone liver transplantation show hypodense areas surrounding the portal venous system and to a lesser extent the intrahepatic inferior vena cava. These changes were considered to represent dilated lymphatic vessels caused by impaired lymphatic drainage of the transplant after total interruption of the lymphatic vessels at surgery. This hypothesis was tested in three piglets after complete surgical interruption of the lymphatic vessels of the liver. Results of histologic examinations and an additional long-term follow-up CT study in one patient suggest that hypodense periportal and pericaval areas are a reversible CT finding in liver transplants caused by lymph stasis.
Three patients with massive lower gastrointestinal bleeding are reported. In all cases, the bleeding source was localized by emergency selective mesenteric angiography. The histologic lesion found in the resected specimen consisted of a minute mucosal ulcer with an abnormally large eroded submucosal artery without evidence of true angiodysplastic changes. The clinicopathological picture is similar to the rare solitary stomach ulceration, described as "Exulceratio simplex Dieulafoy."
Malignant hemangioendothelioma of the thyroid gland, which most often originates in a hemorrhagic nodule, is a well-known entity in European alpine regions with endemic goiter. In other parts of the world it very rarely has been diagnosed. This tumor may display considerable morphologic variation and often has been interpreted as a variant of undifferentiated carcinoma. In 13 out of 20 thyroid tumors, classified by light microscopy as malignant hemangioendothelioma, Factor VIII-related antigen, a marker for endothelial cells, was demonstrated in neoplastic cells with the help of immunohistochemical technics applied to conventional paraffin sections. In one case, in which material suitable for electron microscopy was available, Weibel-Palade bodies were found in tumor cells. These findings add strong support to the notion of an endothelial origin of this neoplasm.
Hyperthyroidism was diagnosed in 53 of 273 thyroid carcinoma patients at the time of their first examination (between 1971 and 1983). This corresponds to 19.5% of these mainly well-differentiated thyroid cancers. In 24 (45%) patients the hyperthyroidism and the thyroid carcinoma were two separate distinct illnesses: of 4 patients with Graves' disease (1.5% of 273), 2 had been operated because of an additional solitary cold nodule, and in the other 2 an occult carcinoma was found intraoperatively. Twenty patients of this group had Plummer's disease: there was a malignant cold nodule within a multinodular goiter with multifocal functional autonomy (MFA)(n = 14) or a carcinoma located near the solitary hot nodule of the toxic adenoma (TA)(n = 6). In these patients the distribution of the different histologies was about the same as in other thyroid cancer patients from this region. The remaining 29 patients (55%) had Plummer's disease, 28 with the classical finding of a solitary toxic adenoma, in which the hot nodule and the malignant tumor were identical. It was possible to confirm this identity histologically in 10 out of 24 cases, retrospectively. Eight of these patients had metastases with radioiodine uptake at the time of the first examination. Of the tumors in this group, 24 were follicular and 5 papillary carcinomas. As a rough estimate, one malignant, scintigraphically hot tumor is found for every 50 benign toxic adenomas. Criteria for the differentiation are: recent growth of the nodule, tumor size of greater than 5 cm diameter or greater than 35 g and an elevated T3-level of less than 0.06 nmol/l/g tumor.(ABSTRACT TRUNCATED AT 250 WORDS)
Young adult female mice were given a total of 90 intraperitoneal injections each of (methyl-3H)thymidine (3HTdR) at intervals of 8 h over 30 days to establish renewal rates of fibroblasts in various locations. Radioautographs prepared from punch biopsy material of the ears, taken repeatedly during the labeling procedure, revealed an approximately linear increase of labeling indices of dermal fibroblasts with time. Labeling indices of fibroblasts at the end of repetitive injections of 3HTdR differed depending on the site and/or type of connective tissues examined. Low values were obtained for fibroblasts in the leptomeninx (3.9%), the tracheal wall (4.4%), the achilles tendon (5.8%) and the dermis of the ear (6.5%), while higher values were registered for fibroblasts located in the lower half of the abdominal dermis (12.3%), peritendinous sheaths (12.6%), the interstitial connective tissue of the thigh muscles (12.9%), the submucosa of the colon (23%), the fibrous capsule of the adrenals (25.7%), and the upper half of the abdominal dermis (26%). These regional differences, with the exception of the skin and possibly of the tracheal wall, did not correlate with local temperature. Possible additional factors influencing fibroblast renewal rates may include the type of connective tissue, the degree of vascularization, mechanical stress and hormonal action. Estimated turnover times, based on the assumptions of a DNA synthesis time of 6 h or more and a linear increase of labeling indices as a function of time of repetitive labeling, range from about 90 to more than 700 days. The higher values approximate the median life span of the mouse strain used.
The translocation of Percoll microspheres (mean diameter 20-30 nm) from the intestinal lumen through the epithelial layer to internal organs was examined in suckling mice using transmission electron microscopy. Repeated administration of this material by gavaging for 7 consecutive days resulted in a heavy particle load of vacuolated enterocytes. A limited amount of Percoll was transported to the subepithelial tissue of both the villous mucosa and Peyer's patches where microspheres were found endocytosed, predominantly by macrophages. Even smaller numbers of particles reached mesenteric lymph nodes and, occasionally, milky spots of the omentum. Minor Percoll aggregates were easily found in Kupffer cells of the liver, indicating hematogenous translocation. Small numbers of particles were regularly detected in perivascular macrophages of the thymic cortex, which are in close contact with surrounding lymphocytes. We conclude that the thymic cortex is not totally inaccessible to particulate matter of the intestinal content.
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A substantial proportion of human peripheral lymphocytes exhibits esterase activity as demonstrated by cytochemical techniques using hexazotized pararosanilin as coupling agent and different alpha-naphthyl compounds, in particular alpha-naphthyl-acetate, as substrates. Esterase-positive lymphocytes showed one or several dots of the reaction product. Plasma cells and macrophages also exhibited marked esterase activity but with diffuse distribution of the reaction product throughout the cytoplasm. The substrate specificity, the time course and the pH optimum of the cytochemical reaction were determined. The results indicate that these lymphocyte esterases are identical with acid lipases. The number of esterase-positive cells reaches a plateau well below 100% (85% for blood lymphocytes) even with optimal staining procedures. The relation between esterase activity and other so-called lymphocyte markers such as sIg and the capacity to form spontaneous rosettes with sheep red blood cells was investigated in peripheral human blood lymphocytes. A fair correlation between rosette formation and esterase activity was found and most of the esterase-positive cells were sIg-negative. However, the fit was never complete. The results suggest that esterase activity is largely characteristic for small peripheral T cells. Almost all blast cells formed following stimulation with Con A or PHA were esterase-positive. Histochemical studies showed that the large majority of the thymocytes in the cortex lacked esterase activity. In lymph nodes, a low proportion of esterase-positive cells was found in the germinal centers, whereas most lymphocytes in the paracortical are were esterase-positive.
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Body weight, liver weight and liver histology in rats 3 weeks after portacaval and distal splenocaval anastomosis were analyzed. Rats with portacaval shunt showed a reduction of body and liver weight and histological signs of liver atrophy. There was no difference between the results in rats with splenocaval shunt and controls.