PubMed HealthSearch

Biomedical subjects

H Gerber

Publications and source records attributed to H Gerber.

At least 19 recordsLinked to original sources

Carcinosarcoma of the urinary bladder: a distinct variant characterized by small cell undifferentiated carcinoma with neuroendocrine features.

The clinicopathological features of two carcinosarcomas of the urinary bladder are reported. The tumours occurred in a 64- and a 66-year-old patient presenting with haematuria and both were polypoid. The epithelial component was consistent with small cell undifferentiated carcinoma with neuroendocrine differentiation, whereas the sarcomatous component did not display specific features. The carcinomatous component showed immunohistochemical reactivity for different epithelial markers as well as for chromogranin and neuron specific enolase. Conversely, the sarcomatous cells stained strongly for vimentin and in one case for muscle actin and smooth muscle actin. The differential diagnosis of biphasic tumours of the bladder is discussed and the literature reviewed.

Actins

[The effect of static magnetic fields on osteoblast activity: an in-vitro study].

The aim of the present study was to investigate whether the influence of static magnetic fields can be demonstrated in an osteoblast cell culture. For this in-vitro study we used osteoblasts originating from the embryonal calvariae of rats. The total material (n = 41) was divided in four groups: a) cell cultures submitted to the fields of attracting magnets (n = 11), b) cell cultures in the fields of repelling magnets (n = 10), c) cell cultures under the influence of demagnetized magnets (sham group, n = 11), d) control cultures (n = 9). The cell cultures were subjected for 21 days to magnetic fields (intensity 178 ml) using Neodynium magnets. Osteoblast activity was histo-chemically determined by staining the alkaline phosphatase produced. The quantitative evaluation was performed by measuring the optical density of the cell cultures and the results were statistically analysed. The results of these in-vitro study are: 1. The optical density of the cell cultures was nearly the same in samples with or without the influence of magnetic fields. 2. No divergent reaction could be found between the application of homogeneous and heterogeneous magnetic fields. 3. The different orientation of homogeneous magnetic fields in vertical or horizontal direction did not effect the osteoblast cell culture. 4. The cellular distribution in the osteoblast cultures does not follow the orientation of the magnetic field lines. 5. The form of the osteoblasts was nearly the same among all four groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Effect of human thyroid stimulating autoantibodies on the radioiodine uptake of the mouse thyroid gland.

Administration of sera from patients with active Graves' disease to nude mice bearing human thyroid xenografts provides the opportunity to compare directly the effects of TSAb on thyroid tissue of different species. The results presented in this paper, namely the fact that only one of 8 Graves' sera increased the RAIU of the nu/nu mouse thyroids modestly while all sera increased the RAIU in the transplanted human tissue considerable, clearly show a species specific effect of TSAb.

Animals

On the genetic basis of equine allergic diseases: II. Insect bite dermal hypersensitivity.

The horses studied were of the Swiss Warmblood breed and most were ELA-typed to assess a possible association of dermal hypersensitivity to insect bites with the major histocompatibility complex. Firstly, the occurrence of the condition was examined in 304 half-siblings sired by six stallions (A to F). Fourteen cases of dermal hypersensitivity were recognized and all were in the 153 offspring of Stallions C, E and F. Most animals of this group were also investigated for chronic hypersensitivity bronchitis: none of the sires displayed clinical signs of dermal hypersensitivity, but Stallions D, E and F were affected by chronic bronchitis. Among the animals investigated for both conditions only one horse showed coincidence of the two diseases as can be expected when the diseases are not correlated. The frequency of manifest dermal hypersensitivity and/or chronic hypersensitivity bronchitis varied in the half-sibling groups of individual sires. These findings suggest that the allergic conditions are independent entities. Secondly, the occurrence of dermal hypersensitivity was studied in three generations of horses at a stud at which Stallion C had exerted a particularly strong influence. A total of 302 animals, all born and raised at this stud, were surveyed over a period of 12 years. The descendants of Stallion C showed a significantly higher incidence (P less than 0.01) of dermal hypersensitivity (two daughters out of 19; eight second generation offspring out of 103; one third generation offspring out of 85) than did the controls of the same age classes but unrelated to Stallion C at the same stud (0 out of 95).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Clonal analysis of human tumors with M27 beta, a highly informative polymorphic X chromosomal probe.

The clonality of human tumors can be studied by X inactivation/methylation analysis in female patients heterozygous for X-linked DNA polymorphisms. We present a detailed study on clonal tumor analysis with M27 beta, a highly informative probe detecting a polymorphic X chromosomal locus, DXS255. The polymorphism detected at this locus is due to variable numbers of tandem repeats. The rate of constitutional heterozygosity detected by M27 beta was 88%. Normal tissue from gastrointestinal mucosa and thyroid showed random, hence polyclonal, patterns. Nonrandom clonal X inactivation was detected in all 22 malignant neoplasms that had been shown to be clonal by other DNA markers, such as antigen receptor gene rearrangements or clonal loss of heterozygosity at 17p and other loci. 16/48 normal blood leukocyte samples (33%) showed considerably skewed X inactivation patterns. Comparison of blood leukocytes and normal tissue indicated that in a given individual, X inactivation patterns may be tissue specific. M27 beta was used to study the clonal composition of 13 benign thyroid nodules from 12 multinodular goiters with rapid recent growth, traditionally termed "adenomas." Nine of them were clonal, whereas four nodules and tissue from a case of Graves' goiter were not, indicating that some, but not all, such thyroid nodules may represent true clonal neoplasms. The M27 beta probe permits one to study the clonal composition by the X inactivation approach of a wide variety of solid tumors from most female patients. As a control, normal tissue homologous to the tumor type of interest is preferable to DNA from blood leukocytes, since the latter may show nonrandom X inactivation patterns in a fairly high proportion of cases. M27 beta may, therefore, be of limited use for the clonal analysis of neoplasms derived from hematopoietic cells.

Clone Cells

Histomorphological and immunohistochemical evidence that human nodular goiters grow by episodic replication of multiple clusters of thyroid follicular cells.

This study was aimed at dissecting the cellular mechanisms that underly the growth of actively expanding human goiter nodules. Thirty-two nodules from different patients, all removed because of steady recent growth, were serially sectioned and screened for 1) histomorphological signs of cell proliferation and 2) in situ expression of the immunohistochemically stained p21ras protooncogene product. Bovine, porcine, and rat thyroid glands (the latter from both T4- and perchlorate-treated animals) were used as controls. In normal glands, only a few follicular cells contain substantial amounts of stainable p21ras. Some of these cells are unusually large, but do not proliferate. In contrast, all goiter nodules contain areas where the epithelial cells are morphologically grossly altered and heavily loaded with p21ras. Cells of this type are mostly clustered in large cohorts coating whole follicles or entire groups of follicles. Only a small fraction of these activated cells actually proliferates at any one point in time. Actively replicating cells are scattered in tiny foci all over the nodules. The earliest proliferating buds are solid, but soon begin to generate microfollicles that enlarge by adding new cells to the follicular epithelium. Regionally heterogeneous p21ras content in morphologically identical cells suggests that growth occurs in bursts and waves. We conclude that goiter nodules grow by episodic proliferation of heterogeneous cohorts of epithelial cells from which new follicles are generated. Only a tiny fraction of all goiter cells proliferate at any one point in time. The molecular mechanisms governing these growth processes are unknown.

Adolescent

[Struma, hyper- and hypothyroidism].

Careful history and physical examination form the basis of thyroid diagnostics. They are important for the choice of the appropriate laboratory and imaging tests such as sonography and scintigraphy. Estimation of FT4 and TSH (measured with a 'sensitive' assay) are nowadays considered to be the principal laboratory tests for thyroid disease. Euthyroidism and hypothyroidism are confirmed by measuring FT4 and TSH (not FT3 or TT3), hyperthyroidism by measuring FT3, FT4 and TSH. If a goitre is observed, the primary tests are TSH and sonography.

Diagnosis, Differential

[Anaphylactoid reaction to Physiogel SRK 4%--a contribution to the controversy about plasma substitutes].

Allergic reactions caused by colloid plasma substitutes are a well known complication in infusion therapy. The incidence of these adverse effects depends on the type of colloid used. Severe anaphylactic or anaphylactoid reactions are generally rare. Nevertheless, the risk of adverse allergic effects is an important aspect of the crystalloid-versus-colloid controversy. The exact pathophysiologic mechanisms remain as yet unclear; reliable prophylactic measures are not universally available. To draw attention to these problems we report a case of severe anaphylactoid reaction to Physiogel SRK.

Anaphylaxis

[Acute cervical syndrome in chondrocalcinosis. 3 elderly patients with calcifications of the transverse atlantis ligament].

Articular chondrocalcinosis, or pseudogout, is characterized by the deposition of calcium pyrophosphate dehydrate (CPPD) crystals. Vertebral involvement in CPPD crystal deposition disease is known and includes in particular the ligamentum flavum, the posterior longitudinal ligament and the intervertebral disc. We report on 3 elderly patients with peracute cervical syndrome. Plain radiographs showed the usual degenerations. Computerized tomography scans revealed a calcified transverse atlas ligament. The erythrocyte sedimentation rate was elevated. Plain radiographs showed chondrocalcinosis of the hands and knees. The symptoms subsided after 2 days' therapy with antiinflammatory drugs. We conclude that chondrocalcinosis may often be an undetected cause of acute cervical vertebral pain in the elderly patient.

Aged

[Clinical examination of the shoulder].

As a consequence of the capacious mobility and great strain, the glenohumeral joint happens to be a frequent site of tenderness or pain. The physician is used to consider the differential diagnosis of "shoulder-arm-pain". Unfortunately he is hardly ever capable to practise himself the special techniques required for the examination of the glenohumeral joint. By a precise clinical examination the exact anatomical localisation of the painful structure can be found in almost every case.

Humans

Different forms of chronic childhood thrombocytopenic purpura defined by antiplatelet autoantibodies.

To determine whether detection of antiplatelet autoantibodies (AAb) to glycoproteins IIb/IIIa and Ib/IX may be useful in defining different forms of chronic thrombocytopenic purpura (TP) in children, we analyzed for AAb the platelet and plasma samples from 36 children with chronic TP (mean duration 4.4 years), from 31 children with normal platelet counts at the time of blood sampling but with chronic TP in the past (mean duration 2.9 years), and from 23 adults with chronic TP; the results were correlated with the clinical data. Antiplatelet autoantibodies were detected in 26 (72.2%) of 36 children with ongoing TP, 15 (48.4%) of 31 children with TP in the past, and 12 (66.7%) of 18 adults with TP. All children with high AAb ratios (greater than 5 times the control mean + 3 SD) were more than 8 years of age at diagnosis (mean age 12.4 years compared with 7.1 years in children with moderate or negative AAb levels; p = 0.003). The results suggest that the outcome for adolescents with high platelet-associated AAb levels may be similar to that of adults, whereas younger children may have a greater chance of spontaneous remission. The children with chronic TP in the past and elevated platelet-associated AAb levels may have a "compensated" TP and therefore may be at risk for relapses. Future studies aimed at serial AAb determination throughout the patients' courses may further define TP subgroups.

Adolescent

Autonomous growth and function of cultured thyroid follicles from cats with spontaneous hyperthyroidism.

Spontaneous feline hyperthyroidism is a unique experimental model of toxic nodular goiter. To determine whether feline toxic goiter is caused by extrathyroidal stimulating factors or by the intrinsic autonomy of follicular cells, primary cultures of enzymatically dissociated follicles from 15 hyperthyroid cat goiters and from 3 normal cat thyroid glands were embedded in collagen gels. Growth and function in chemically defined media were assessed by autoradiography after double labeling with 3H-thymidine and 131I-Na. Iodine organification in follicles from normal glands was TSH dependent, but intense radioiodine organification occurred in follicles from hyperfunctioning goiters even in the absence of TSH. Similarly, twice as many follicular cells of hyperfunctioning thyroid tissue, maintained without TSH in the medium, were labeled after exposure to 3H-thymidine than in follicles from normal glands. The results strongly suggest that intrinsic alterations of cell function lead to autonomy of follicular growth and function and subsequently to the development of hyperplastic nodules, causing thyrotoxicosis. The reason for the focal nature of the disease remains an unresolved challenge. Further investigation using this model may further understanding of the growth of autonomous endocrine tumors.

Animals

The genetic basis of equine allergic diseases. 1. Chronic hypersensitivity bronchitis.

The genetic influence on chronic hypersensitivity bronchitis (CB) was investigated in families at two studs and among half-siblings of three affected and three non-affected sires at several farms. The family members at the two studs were born and raised under the same conditions, whereas the half-siblings were kept individually under very different conditions and were exposed to various environmental factors. The diagnosis was based on long-term observations and multiple clinical examinations at each of the two studs. In the half-sibling group, the diagnosis was based on the individual history and on a thorough clinical examination. The history of all horses suggested the disease was caused by allergies (symptoms provoked by hay). Statistical analysis of the data in the first study showed that a greater percentage of off-spring of two affected parents developed CB (9 of 13) than those with only one affected parent (23 of 48) and those with two healthy parents (5 of 29). The distributions of the affected offspring in these three categories (none, one or both parents affected) differed significantly (P less than 0.005) from what would have been expected without a genetic effect. The tendency to develop the disease was inherited equally from dams or sires. In the second stud fewer animals (n = 42) were included in the study, but the results were similar. Parents without a history of CB produced off-spring with a low incidence of disease (1 of 16) compared with a higher incidence among descendants of one or two affected parents (10 of 26; P = 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Comparison of FRTL-5 cell growth in vitro with that of xenotransplanted cells and the thyroid of the recipient mouse.

The present work was designed to compare in vitro cell growth kinetics with in vivo growth under conditions as similar as possible using labeling with [3H]thymidine. To this purpose, FRTL-5 cells were cultured as monolayers and as three-dimensional spheroids embedded in collagen gels and transplanted simultaneously into nude mice treated with perchlorate and a low iodine diet. The growth of the transplants was compared to that of the thyroids in host mice. In the intact thyroid, the fraction of [3H]thymidine-labeled follicular cells (FLC; 24-h labeling) increased sluggishly to a maximum of 10% after 3 weeks of goitrogen exposure, with a subsequent autoregulatory decrease to 3% at 7 weeks. A 4-fold higher FLC was found in six adenomas, indicating focal failure of growth-restraining mechanisms. In nonconfluent monolayer cultures the FLC was as high as 90%, even within large individual clusters where cells are in tight mutual contact. Solid, highly cellular grafts growing from transplanted monodispersed cells showed an average FLC of 20%, which is 5 times higher than the FLC in the identically stimulated mouse thyroid. In collagen-embedded cells, forming three-dimensional spheroids, the mean FLC decreased from 70% at 1 week in vitro (40% in vivo) to 20% at 3 weeks both in vitro and in vivo, suggesting effective auto-regulation of excessive growth in both conditions. However, these FLC were again much higher than the 3% FLC in simultaneously assessed host thyroids. The difference remained throughout the 45-day period studied. We conclude that FRTL-5 cells growing as monolayers and as three-dimensional spheroids in vitro or after xenotransplantation in vivo invariably show much higher proliferation rates under comparable environmental conditions than the normal follicular epithelium in the thyroids of host mice. The one exception is the confluent monolayer with near-zero growth, while densely packed three-dimensional transplants still grow intensively. Although growth-retarding cell to cell interactions are also clearly operative in growing FRTL-5 cells, they are less effective than those dampening the replication rate of the thyrocytes within the monolayer hull of normal follicles. A local failure of these mechanisms, allowing growth rates comparable to those of grafted FRTL-5 cells results in adenoma formation in normal thyroids. These observations call for caution in the transfer of in vitro growth studies with FRTL-5 cells to in vivo conditions prevailing in the normal thyroid.

Adenoma

Thyroid cell lines in research on goitrogenesis.

Thyroid cell lines have contributed a lot to the understanding of goitrogenesis. The cell lines mostly used in thyroid research are briefly discussed, namely the rat thyroid cell lines FRTL and FRTL-5, the porcine thyroid cell lines PORTHOS and ARTHOS, The sheep thyroid cell lines OVNIS 5H and 6H, the cat thyroid cell lines PETCAT 1 to 4 and ROMCAT, and the human thyroid cell lines FTC-133 and HTh 74. Chinese hamster ovary (CHO) cells and COS-7 cells, stably transfected with TSH receptor cDNA and expressing a functional TSH receptor, are discussed as examples for non-thyroidal cells, transfected with thyroid genes.

Animals