Distinct genetic and immunological features in patients with onset of IDDM before and after age 40

OBJECTIVE

Young age at onset is a relevant parameter associated with a rapid progression of IDDM. Our major aim was to define differences between IDDM patients with age at diagnosis > 40 years and adult IDDM with onset at a younger age.

RESEARCH DESIGN AND METHODS

The correlation between islet-related antibodies (islet cell antibodies [ICAs] and antibodies [Abs] to GAD and the tyrosine phosphatase IA2), T-cell responses to GAD peptides and HLA class II isotypes was investigated in 23 IDDM patients 12-38 years of age at onset (group 1), 24 patients with IDDM > 40 years of age at onset (group 2), and 12 healthy control subjects. ICAs were measured by indirect immunofluorescence, and GAD-Ab and IA2-Ab were measured by immunoprecipitation tests. T-cell responses against GAD peptides, which had been identified as typical for IDDM, were tested by 5-day proliferation assays. HLA class II alleles were typed by polymerase chain reaction.

RESULTS

ICAs and GAD-Abs were more prevalent in IDDM patients than in control subjects (P < 0.001), but only IDDM group 1 had IA2-Abs (P < 0.001 compared with IDDM group 2 and control subjects). Moreover, antibody combinations differed between IDDM patients of groups 1 and 2. T-cell responses to GAD peptides were seen in 67% of IDDM group 1 and in 71% of IDDM group 2 (P < 0.02 compared with control subjects). IDDM patients of group 1 were more frequently DR4+/DQ8+ and less frequently DR2+/DQ0602+ compared with IDDM patients of group 2 (P < 0.05).

CONCLUSIONS

Our data provide strong evidence for humoral and cellular autoimmunity in adult IDDM patients with onset both before and after 40 years of age. However, late-onset differs from young-onset IDDM with respect to Ab profiles, especially a lack of IA2-Ab, and HLA class II types. These findings have consequences for the diagnostic strategy for identifying slow-onset IDDM in individuals after 40 years of age.

Identification of a C-terminal binding site for G-protein betagamma-subunits in phosducin-like protein

Phosducin-like protein (PhLP) has recently been identified as a ubiquitous inhibitor of G-protein betagamma-subunit (G betagamma)-mediated signaling, with an affinity about 5-fold lower than that of phosducin. The G betagamma binding site of phosducin has been suggested to be contained in its N-terminus. A region corresponding to this N-terminus is lacking in PhLP, suggesting that PhLP must utilize a different mode of G betagamma binding. To map the G betagamma binding site in PhLP, a series of deletion mutants were constructed, expressed in E. coli as glutathione S-transferase (GST) fusion proteins, and the purified fusion proteins were examined for their ability to attenuate G(o) GTPase activity. Progressive N-terminal truncations of PhLP caused only minor reductions in potency, whereas the complementary N-terminal PhLP fragments turned out to be inactive. We further identified a short C-terminal segment comprising residues 168 to 195 that inhibited G0 GTPase activity similar in efficacy and potency to full-length PhLP. This C-terminal fragment was also capable of antagonizing a second G betagamma-mediated function, the enhancement of rhodopsin phosphorylation by the beta-adrenergic receptor kinase. Taken together, these data indicate that PhLP interacts with G betagamma via a short C-terminal binding site which is distinct from that identified previously in phosducin.

[Analysis of primary management of bladder malfunction in traumatic paraplegic patients]

Intermittent catheterisation is the demanded therapy of bladder paralysis during the spinal shock. We investigated the realisation of this concept. In 1994 after first treatment in other hospitals 97 patients were treated in the Thuringian Spinal Cord Centre Sülzhayn. The primary treatment of the paralysed bladder was: indwelling catheter: 44 patients (45.4%), suprapubic catheter: 30 patients (30.9%). Only 15 patients (15.5%) were catheterized intermittently. No urological treatment was carried out in seven cases.

CONCLUSION

The primary treatment of bladder analysis in spinal cord injured patients has to be improved.

Expression of interleukin-1 in human pheochromocytoma

Cytokines and in particular interleukin 1 (IL-1) play a role in the micro-environment of various tumors. In addition, it is well established that IL-1 is a neurotrophic, angiogenetic and fibrogenetic factor. Using in situ hybridization we analyzed the expression of endogenous IL-1 in human pheochromocytoma (PCC). With the help of specific antibodies to B- and T-cells, macrophages, and neuroendocrine cell antigens, we characterized the distribution and localization of various cell types in human PCC. The combination of immunohistochemistry and in situ hybridization was eminently suited to defining the exact cellular source of IL-1 expression. In situ hybridization and immunostaining revealed that IL-1 mRNA was located primarily in the tumor cell itself. IL-1 may therefore constitute an important paracrine/autocrine factor in neuroendocrine tumors.

Haemolysis in hepatitis A virus infections coinciding with the occurrence of autoantibodies against triosephosphate isomerase and the reactivation of latent persistent Epstein-Barr virus infection

Haemolysis has been observed frequently as a complication of acute hepatitis A virus (HAV) infection. However, the pathogenic mechanism has not been elucidated completely. In individual cases the detection of anti-erythrocyte antibodies of unknown specificity was described. The raised serum IgM fraction was shown to consist partially of autoantibodies. Previously, we detected autoantibodies of immunoglobulin class M directed against triosephosphate isomerase (IgM anti-TPI) in patients with infectious mononucleosis. These autoantibodies are able to induce haemolysis. In this study the occurrence of IgM anti-TPI in acute HAV infections and other viral diseases has been investigated. In 33 of 134 patients suffering from HAV infection (IgM anti-TPI was detected. Haematological and chemical data were available from seven of these 33 patients. Mild-to-moderate signs of haemolysis correlating with the IgM anti-TPI titre in the follow-up examinations were demonstrated. The presence of IgM anti-TPI in HAV infections is connected with a reactivation of a latent persistent EBV infection. In other viral infections both the detection of IgM anti-TPI and evidence of a reactivated EBV infection is rare. Thus, we anticipate that IgM anti-TPI antibodies occurring with the reactivation of a latent persistent EBV infection take part in provoking haemolysis in acute HAV infections.

[Cytokeratin expression of benign and malignant epithelial thyroid gland tumors. An immunohistologic study of 154 neoplasms using 8 different monoclonal cytokeratin antibodies]

Using 8 different monoclonal antibodies, immunohistology was performed on 36 follicular adenomas and on 28 follicular, 34 papillary, 27 medullary and 29 anaplastic carcinomas of the thyroid. The panel of antibodies was directed against broad-spectrum cytokeratins (pan-CK, antibody lu-5), against basic and acid high-molecular-weight CK of types #1, 5, 10 and 14, against basic (#5 and 6) and acid high-molecular-weight CK (#13) and against basic (#7 and #8) and acid low-molecular-weight CK (#19 and #20). With the exception of a large number of anaplastic carcinomas, nearly all other tumours exhibited strong immunoreactivity with antibodies against pan-CK, CK 8 and CK 19. CK 20 expression was exclusively shown for 2 medullary carcinomas. Reactivity for high-molecular-weight CK could only, each time focally, be demonstrated for 14 papillary and 2 follicular carcinomas and for 2 anaplastic carcinomas with partial squamous differentiation. Thirteen anaplastic carcinomas were not decorated by any of the CK antibodies applied. CK 7 staining exceeding the staining of individual cells was observed in 26 papillary cancers. In contrast, such a finding could only be obtained with each one follicular adenoma, medullary carcinoma and anaplastic carcinoma and with 5 follicular carcinomas. These results confirm earlier studies in that CK 20 expression among thyroid tumours is restricted to the neuroendocrine medullary carcinomas and that in a larger percentage of anaplastic thyroid carcinomas an epithelial phenotype can not be demonstrated even upon using broad-spectrum CK antibodies. New is the finding that there exist considerable differences between papillary carcinomas and all other non-papillary thyroid tumours regarding CK 7 expression. This result might be of differential diagnostic value for the distinction of follicular and papillary thyroid neoplasias which sometimes have an overlapping histological pattern.

In vivo and in vitro evidence for iodide regulation of major histocompatibility complex class I and class II expression in Graves' disease

Increases in thyroid cell major histocompatibility complex (MHC) class I and class II expression have been suggested to be an important factor in the development or perpetuation of Graves' disease. It is hypothesized that elevations result in abnormal presentation of thyroid antigens to immune cells, and that iodide and/or methimazole (MMI) are effective therapeutic agents because, at least in part, of their suppression of MHC expression. In this report, we show that Graves' patients pretreated with iodide only 4 days before surgery have lower levels of MHC class I and class II RNA levels in their thyroid tissue than do patients with no iodide pretreatment (P < 0.001 and 0.03, respectively). Because patients in both groups are treated with MMI and because the change is independent of the amounts of MMI used to treat patients, the class I and class II changes cannot be ascribed to MMI. The iodide action to decrease MHC class I and class II RNA levels was duplicated using cultured human thyroid cells in vitro; the iodide effect was dependent on the iodide concentration, was not duplicated by chloride, was not associated with an alteration in cAMP levels or with a change in thyrotropin receptor RNA levels, and was evident in gamma-interferon-treated cells. The data suggest, therefore, that the therapeutic action of iodide in Graves' patients is associated with decreased MHC gene expression, that this action is a direct effect of high concentrations of iodide on the thyroid cells, and that altered MHC gene expression in the target tissue may well be associated with the development or perpetuation of Graves' disease.

Expression of phosducin in a phosducin-negative cell line reveals functions of a Gbetagamma-binding protein

Phosducin is a member of the large group of proteins that bind to G-protein betagamma-subunits (Gbetagamma) and whose biological functions are often unknown. Human A431 cells do not contain detectable amounts of phosducin. We generated A431 cells expressing phosducin at a level of approximately 1 pmol/mg of cytosolic protein, which is approximately 10% of the phosducin level in brain. cAMP accumulation in response to beta2-adrenergic receptor agonists was enhanced at early times in phosducin-expressing cells, but reached a lower plateau than in control cells. Permeabilization of the cells with digitonin did not change this pattern, but allowed the introduction of specific inhibitors: antibodies to phosducin abolished all differences between the two cell lines. Inhibitors of the beta-adrenergic receptor kinase abolished the differences at early time points. An almost complete loss of beta2-adrenergic receptor desensitization in the phosducin-expressing cells was also observed when intact cells were desensitized and receptor function was then determined in membrane preparations. Inhibition of protein kinase A accentuated the effects of phosducin, suggesting that also in vivo phosducin is regulated by this kinase. These data indicate that phosducin affects G-protein-mediated signaling in at least two ways: it dampens the overall responsiveness, and it impairs the rapid desensitization mediated by the beta-adrenergic receptor kinase.

[Autonomy and malignancy of thyroid glad tumors. A critical analysis of the literature on the existence of hyperfunctioning follicular and papillary thyroid gland carcinomas]

Data in the literature communicated in 63 publications were evaluated in which scintigraphically warm or hot nodules were described as identical to a follicular or papillary carcinoma diagnosed based on histology of the resection specimen, thus suggesting autonomous hyperfunction of a malignant thyroid neoplasia. In the majority of cases, this assumption could not be accepted, or only within strict limits. In these patients, it appeared more likely that the carcinoma was located adjacent to or within a benign hyperfunctioning thyroid area or that large masses of a thyroid carcinoma had only simulated the picture of a hyperfunctioning nodule by suppression of endogenous TSH and thus of the residual parenchyma's function. In other cases, the diagnosis of a hyperfunctioning thyroid carcinoma had to be doubted or rejected owing to the lack of plausibility of the documented morphological findings. At the end of the literature survey, only 10 case descriptions unequivocally verified that, though very rarely, a papillary or follicular thyroid carcinoma may manifest itself as a solitary warm or hot thyroid nodule. Such a scintigraphical finding thus cannot be regarded as proof of benignancy of a given thyroid tumour.

DNA cytophotometry and prognosis in typical and atypical bronchopulmonary carcinoids. A clinicomorphologic study of 100 neuroendocrine lung tumors

Surgical material obtained from 100 patients with typical carcinoids (TC) and atypical carcinoids (AC) of the lung (including 100 primary, four residual tumors, and four lymph node or distant metastases) was investigated by conventional histology and scanning DNA cytophotometry. Of the 60 TC (96%), 58 exhibited euploid DNA histograms compared with only 20 (50%) of the 40 AC. The morphologic findings were related to the patients' survival (median observation period, 9 years). Statistical analyses disclosed the histologic type of disease (TC versus AC) and the DNA content of tumors (euploid versus aneuploid) to affect prognosis significantly (p < 0.001). Deaths resulting from tumor were exclusively observed among patients with atypical (eight of 40) or DNA aneuploid carcinoids (eight of 22). Six patients were alive with persistent tumor manifestations 3 to 20 years after initial diagnosis, four with DNA diploid primary carcinoids. The presence of lymph node metastases alone was not associated with poor prognosis as long as the primary tumor or the related metastases showed a diploid DNA content. DNA cytophotometry thus might be regarded as an adjunctive prognostic criterion in individual carcinoid cases.

[Morphology and clinical aspects of immune thyroid diseases]

The aetiopathogenesis of autoimmune thyroid disease is still a matter for discussion. Morphologically, these illnesses are associated with a broad spectrum of overlapping changes. Thus, pathology cannot serve as the logical basis for a new classification. Therefore this overview makes use of the conventional nomenclature of clinically established entities and includes recently defined lesions. Besides histological characteristics, details of differential diagnostic value are presented in the context of clinical and laboratory data relevant for pathological classification.

Interactions of phosducin with defined G protein beta gamma-subunits

Phosducin has recently been identified as a cytosolic protein that interacts with the beta gamma-subunits of G proteins and thereby may regulate transmembrane signaling. It is expressed predominantly in the retina but also in many other tissues, which raises the question of its potential specificity for retinal versus nonretinal beta gamma-subunits. We have therefore expressed and purified different combinations of beta- and gamma-subunits from Sf9 cells and have also purified transducin-beta gamma from bovine retina and a mixture of beta gamma complexes from bovine brain. Their interactions with phosducin were determined in a variety of assays for beta gamma function: support of ADP-ribosylation of alpha 0 by pertussis toxin, enhancement of the GTPase activity of alpha 0, and enhancement of rhodopsin phosphorylation by the beta-adrenergic receptor kinase 1 (betaARK1). There were only moderate differences in the effects of the various beta gamma complexes alone on alpha 0, but there were marked differences in their ability to support betaARK1 catalyzed rhodopsin phosphorylation. Phosducin inhibited all beta gamma-mediated effects and showed little specificity toward specific defined beta gamma complexes with the exception of transducin-beta gamma (beta1 gamma1), which was inhibited more efficiently than the other beta gamma combinations. In a direct binding assay, there was no apparent selectivity of phosducin for any beta gamma combination tested. Thus, in contrast to betaARK1, phosducin does not appear to discriminate strongly between different G protein beta- and gamma-subunits.

[Sporadic unilateral adrenal medullary hyperplasia--a rare cause of hypertension]

Sporadic adrenomedullary hyperplasia (AMH) is characterized by a clinical history of hypertension, increased plasma and/or urinary catecholamine levels and histomorphometric evidence of increased adrenal medullary mass in the absence of MEN 2 syndrome. The case of a 42-year-old female patient is reported who presented with typical clinical and laboratory findings of episodic hypertension and elevated plasma and urinary catecholamines. Sonography and computed tomography revealed no abnormality, but 131I-metaiodobenzylguanidine (131I-MIBG) scintigraphy showed increased uptake in the right adrenal. Transabdominal unilateral adrenalectomy was performed. The right adrenal gland was macroscopically inconspicuous. Upon histomorphometry, however, an increased adrenal medullary cell mass was shown, thus confirming AMH. Two years following surgery the patient is asymptomatic and normotensive.

Inhibition of G-protein betagamma-subunit functions by phosducin-like protein

Phosducin is a cytosolic protein predominantly expressed in the retina and the pineal gland that can interact with the betagamma subunits of guanine nucleotide binding proteins (G proteins) and thereby may regulate transmembrane signaling. A cDNA encoding a phosducin-like protein (PhLP) has recently been isolated from rat brain [Miles, M. F., Barhite, S., Sganga, M. & Elliott, M. (1993) Proc. Natl. Acad. Sci. USA 90, 10831-10835. Here we report the expression of PhLP in Escherichia coli and its purification. Recombinant purified PUP inhibited multiple effects of G-protein betagamma subunits. First, it inhibited the betagamma-subunit-dependent ADP-ribosylation of purified alpha(o) by pertussis toxin. Second, it inhibited the GTPase activity of purified G(o). The IC50 value of PhLP in the latter assay was 89 nM, whereas phosducin caused half-maximal inhibition at 17 nM. And finally, PhLP antagonized the enhancement of rhodopsin phosphorylation by purified betagamma subunits. The N terminus of PhLP shows no similarity to the much longer N terminus of phosducin, the region shown to be critical for phosducin-betagamma-subunit interactions. Therefore, PhLP appears to bind to G-protein betagamma subunits by an as yet unknown mode of interaction and may represent an endogenous regulator of G-protein function.

[Blood group antigen expression in papillary carcinoma of the thyroid gland. An immunohistochemical and clinical study of expression of Lewis, ABO and related antigens]

Nine monoclonal antibodies, lectin from Ulex europaeus and neuraminidase enzyme were employed to demonstrate the occurrence of type 1 and type 2 blood group antigens in 104 cases of papillary carcinoma of the thyroid. The reagents applied, recognize the following blood group related antigens: CA-50 (sialylated type 1 precursor), CA-19-9 (sialylated Le(a)), Le(a), Le(b), A, B, H, Le(x), sialylated Le(x), and Le(y). Immunohistochemical studies revealed that papillary carcinoma of the thyroid, in contrast to histologically normal thyroid tissue, is characterised by a progressive expression of blood group antigens. Most tumours (84%) reacted with C-50 antibody, whereas only a minority of the tissues demonstrated the CA-19-9 antigen (38%). Type 2 structures Le(x) (47%) and Le(y) (13%) were found less often than their corresponding type 1 isomers Le(a) (71%) and Le(b) (62%). Desialylation with neuraminidase increased the Le(a) and Le(x) staining intensity in 27 and 44 case, respectively. Of the A, B, H antigens the A determinants encountered most frequently (24%). Comparative examinations of sequential sections of the same tumour revealed coexpression of type 1 antigens in the same areas. In carcinomas showing type 1 and type 2 antigen reactivity, a complementary distribution of the structures in different tumour areas was often demonstrated. Some tumours presented combined type 1 and type 2 antigen expression in the same cells, however, in distinct areas within the cell. A follow-up examination was carried out in 68 of the 104 cases. The observation time ranged from 12 to 217 months. Thirteen patients suffered from recurrence, of which 7 died. While lymphatic metastases occurred in 39 tumours, distant metastases were detected in 6 patients. Most of the recurrences were found in patients with tumour classification pT4 (n = 19), whereas none of the pT1 carcinomas (n = 20) showed recurrence. The clinical results were compared to the blood group antigen expression results. There was no correlation between antigen expression and differentiation degree of the tumour. The pT4 tumours showed a significant higher expression of the CA-50, CA-19-9, Le(a) and Sialyl Le(x) structures. Carcinomas expressing the Le(y) antigen were associated with a significant higher level of metastasizing capacity. The Le(y), H type 1 and H type 2 antigens occurred more frequently in recurrent tumours (n = 14). In contrast, none of the patients whose carcinomas expressed the A-antigens (n = 14) suffered from a recurrence or hematogenous metastasis. Multiple stepwise regression analysis was carried out to check the importance of each staining and clinical factor. In this analysis, "distant metastasis' was the most important parameter, whereas the staining results were of minor statistical importance.

Prognostic significance of nuclear DNA content and proliferative activity in renal cell carcinomas. A clinicopathologic study of 58 patients using mitotic count, MIB-1 staining, and DNA cytophotometry

BACKGROUND

For a variety of human malignancies, static DNA cytophotometry and immunostaining for the Ki-67 antigen using the antibody MIB-1 have provided significant prognostic information.

METHODS

Surgical specimens of 58 renal cell carcinomas (RCCs) were investigated by conventional histology, DNA cytophotometry, and MIB-1 immunostaining.

RESULTS

The MIB-1 indices and DNA data were found not only to be significantly correlated with various other morphologic parameters, but also to the clinical behavior of RCC. In the course of this study (median observation period: 31 months), 27% of patients died from RCC. None of these patients belonged to the group of 37 patients with RCCs exhibiting diploid or euploid DNA histograms. Lethal outcome occurred in only 16 of the 21 patients (76%) with noneuploid or aneuploid histogram tumors (P < 0.0001). According to their MIB-1 indices and upon choosing different cutoff levels, the 58 RCCs were categorized into 2 groups with either low or high proliferative activity. Using the median and the mean MIB-1 index as cutoffs, none of the patients with tumors showing low proliferative activity had died, whereas 16 of 29 patients (55%) or, respectively, 16 of 25 patients (64%) with tumors exhibiting high proliferative activity, had died from RCC (P < 0.0001).

CONCLUSIONS

In addition to tumor grade and stage, both a high MIB-1 index and a noneuploid or aneuploid DNA histogram of a given RCC have the potential to identify tumor patients with an impaired prognosis.

[Morphology and clinical features of autoimmune thyroid diseases]

The aetiopathogenesis of autoimmune thyroid diseases is the subject of various partly contradicting hypotheses and theories. Morphologically, these illnesses are associated with a broad spectrum of overlapping changes. Thus, pathology either can not serve as the logical basis for a new classification of autoimmune thyroid diseases. This overview therefore makes use of the conventional nomenclature of clinically established entities and includes recently defined lesions. Besides histological characteristics details of differential diagnostic value are presented in the context of clinical and laboratory data relevant for pathological typing.

[Inflammatory pseudotumor of the liver--rare differential diagnosis of undetermined hepatic space-occupying lesion. Case report and review of the literature]

Hepatic masses are predominantly malignant, and whereas benign tumors are rare. We report the case of a 65-year-old man who presented with an anomalous hepatic mass. Following explorative laparotomy and left lateral segmentectomy (II/III), the patient was diagnosed as having an inflammatory pseudotumor of the liver. So far only 102 cases of "inflammatory pseudotumor of the liver" have been reported in the literature. Asia is a geographical center for this tumor entity, which mostly affects men. The major symptoms are nonspecific: fever, weight loss and general fatigue. The prognosis of "inflammatory pseudotumor of the liver" is very good. In 98% of the cases, a cure has been obtained after surgical therapy, but conservative therapy approaches also yield good results.

Absence of RET proto-oncogene point mutations in sporadic hyperplastic and neoplastic lesions of the parathyroid gland

We investigated the possible role of RET proto-oncogene mutations in the development of sporadic hyperplastic, benign, and malignant parathyroid lesions. DNA extracted from paraffin-embedded specimens of forty parathyroid lesions was screened for RET proto-oncogene point mutations in exons 10, 11, and 16 by nonisotopic polymerase chain reaction-based single-strand conformation polymorphism and heteroduplex gel electrophoresis. The nucleotide sequence of samples with aberrant band patterns was identified by nonisotopic direct sequencing of polymerase chain reaction-amplified DNA. Parathyroids of seven patients with multiple endocrine neoplasia type 2A (MEN 2A) and MEN 2B served as positive controls. None of the eight hyperplastic lesions, three cases of parathyromatosis, ten parathyroid adenomas, eleven carcinomas or one normal parathyroid gland contained mutations in each of the three RET exons tested. Six MEN-2A-associated hyperplastic glands exhibited identical band shifts in the polymerase chain reaction single-strand conformation polymorphism analysis of exon 11, which corresponded to a Cys 634-->Arg substitution in the nucleotide sequence analysis (TGC-->CGC), whereas in the MEN 2B parathyroid specimen a point mutation was found at codon 918 of exon 16 (ATG-->ACG), causing a Met 918-->Thr substitution. Our data indicate that RET mutations of the MEN 2 loci in exons 10, 11, and 16 are not involved in the development of sporadically occurring benign or malignant parathyroid lesions. Furthermore, our results are in accordance with the observation that MEN 2A patients with Cys 634-->Arg (germline) mutations have a higher risk of developing parathyroid disease than those with other mutations at codon 634.

The Golgi-localization of yeast Emp47p depends on its di-lysine motif but is not affected by the ret1-1 mutation in alpha-COP

The Saccharomyces cerevisiae EMP47 gene encodes a nonessential type-I transmembrane protein with sequence homology to a class of intracellular lectins defined by ERGIC-53 and VIP36. The 12-amino acid COOH-terminal cytoplasmic tail of Emp47p ends in the sequence KTKLL, which conforms with the consensus for di-lysine-based ER-localization signals. Despite the presence of this motif, Emp47p was shown to be a Golgi protein at steady-state. The di-lysine motif of Emp47p was functional when transplanted onto Ste2p, a plasma membrane protein, conferring ER localization. Nevertheless, the di-lysine motif was required for Golgi-localization of Emp47p and showed the same charge-independent, position-dependent characteristics of other di-lysine motifs. Alpha-COP has been shown to be required for ER localization of di-lysine-tagged proteins. Consistent with this finding, the Ste2p-Emp47p hybrid protein was mislocalized to the cell surface in the alpha-COP mutant, ret1-1. Surprisingly, the Golgi-localization of Emp47p was unaffected by the ret1-1 mutation. To investigate whether Emp47p undergoes retrograde transport from the Golgi to the ER like other di-lysine-tagged proteins we developed an assay to measure this step after block of forward transport in a sec12 mutant. Under these conditions retrograde transport led to a specific redistribution of Emp47p from the Golgi to the ER. This recycling occurred from a Golgi subcompartment containing alpha 1,3 mannose-modified oligosaccharides suggesting that it originated from a medial-or later Golgi compartment. Thus Emp47p cycles between the Golgi apparatus and the ER and requires a di-lysine motif for its alpha-COP-independent, steady state localization in the Golgi.

[Colon carcinoma simulating retroperitoneal inflammatory pseudotumor. Case report of so-called abdominal inflammatory fibrosarcoma]

Resection of a stenosing colon tumor in an 89-year-old male patient led to the diagnosis, unusual at this age, of an inflammatory pseudotumor (synonym: plasma cell granuloma) of the retroperitoneum and mesentery, which invaded the large bowel and showed infiltration of one regional lymph node. Histology and immunohistochemistry (demonstrating a myofibroblastic phenotype of the proliferating spindle cells and polyclonality of abundantly present plasma cells) of the specimen resembled previously reported lesions in various locations. The etiology and exact nosological classification of inflammatory pseudotumors are not yet unequivocally settled. The recently published conjecture that such lesions of the retroperitoneum represent a separate entity with features of a malignant neoplasm is discussed.

[Morphological typing, evaluation of tumor dignity and prognosis and etiologic classification of adrenomedullary and adrenocortical neoplasias]

The aim of morphological tumour diagnosis is to answer clinical questions on type, biological potential, prognosis and aetiology of individual neoplasms. The limitations and perspectives of different methods used in the diagnosis of adrenal tumours, ranging from histology to molecular genetic DNA analyses, are described. When surgical specimens from adrenal neoplasms cannot be typed on the basis of histology and/or with clinica data (e.g., endocrine symptoms and history) as adrenocortical tumours, phaeochromocytomas or metastases to the adrenal, immunohistological investigations with a panel of different antibodies are necessary. After identification of the tissue derivation of an individual adrenal tumour, its biological potential must be assessed. Among adrenocortical neoplasms, adenomas and carcinomas can be distinguished by evaluation of various histological parameters (including structural features and signs of invasion) according to defined algorithms. In addition, conventional histology (by estimation of mitotic activity) allows the discrimination of tumours with especially high malignant potential from other adrenocortical carcinomas. In contrast, among adrenomedullary tumours even the combined use of histological, immunohistological and DNA cytophotometric techniques only allows the definition of risk groups (benign versus suggestive of malignancy), while reliable recognition of an individual malignant phaeochromocytoma is so far impossible. The question as to whether a particular phaeochromocytoma represents a sporadic tumour or a neoplasm inherited as one feature of a defined syndrome cannot be answered with the above methods, but only by the application of molecular genetic techniques.

Functional and morphological changes of the thyroid gland following 5 days of pulsatile TRH stimulation in male rats

The aim of the present study was to evaluate in vivo the selective effects of a small increase in plasma TSH levels on thyroid function, proliferation and morphology. Chronically catheterized male Sprague-Dawley rats were stimulated i.v. over 5 days either with TRH (2 micrograms TRH in 100 microliters 0.9% (w/v) NaCl (TRH-P) or the NaCl carrier alone (P), both given as pulses every 2 h. Control groups were cotreated i.v. with 10 micrograms thyroxine (T4)/100 g body weight per day (TRH-P + T4) starting 2 days before pulsatile stimulation. TSH plasma levels were approximately doubled by TRH-P (P < or = 0.001), T4 plasma levels significantly increased (P < or = 0.001) but tri-iodothyronine plasma levels did not change compared with treatment with P. No significant changes between groups were found in thyroid weight and in intrathyroidal iodine content, but the percentage of 5-bromo-2'-desoxyuridine-labelled thyrocytes as a marker of proliferation in TRH-P-treated animals was significantly increased over P or TRH-P + T4 (P < or = 0.001). Ultrastructural analysis of the thyroid evaluated by electron microscopy revealed a significant increase in the number of lysosomes (P < or = 0.001). The size of the endoplasmic reticulum (ER) in relation to the cytoplasm was significantly increased when treated with TRH-P compared with P or TRH-P + T4 (P < or = 0.001). Post-embedding immunogold staining revealed Tg as a major product within ER cisternae. Immunogold labelling was moderate in controls and higher densities of gold particles were obtained in TRH-P-treated animals (P < or = 0.001). In conclusion, short-term pulsatile TRH stimulation increasing the plasma levels of immunoreactive TSH only twofold is capable of inducing hypertrophy of the thyrocytes by gross ultrastructural changes which are paralleled by an increase in circulating T4. These data underscore the dominant role of TSH on thyroid ultrastructure within the narrow boundaries of normal physiological regulation.

Multiple endocrine neoplasia type 1 (MEN 1) revisited

Multiple endocrine neoplasia type 1 (MEN 1) is an inherited disease of the neuroendocrine cell system affecting primarily the parathyroids, pancreas, duodenum and the anterior pituitary. The pancreatic and duodenal tumours may metastasize, but generally have a low malignant potential. The diagnosis of MEN 1 is usually made in the second decade of life and based on the involvement of at least two organs and a family history. The recent discovery of the MEN 1 locus on the centromeric region of the long arm of chromosome 11 may become a further diagnostic criterion. The use of flanking DNA markers permits presymptomatic testing for MEN 1 in affected families.

Isolation and characterization of a stable Chinese hamster ovary cell line overexpressing the plasma membrane Ca(2+)-ATPase

Stable Chinese hamster ovary (CHO) cell lines overexpressing the human plasma membrane Ca(2+)-ATPase (PMCA) were generated, and three independent cell clones were characterized in details. They overexpressed high amounts of active PMCA pump (15-20 times over the amount of endogenous PMCA) as indicated by experiments in which the formation of the phosphoenzyme intermediate and the uptake of Ca2+ by microsomes were measured. Immunocytochemistry experiments coupled to the biotinylation of the pump in the intact cells indicated the correct deliver of the expressed pump to the plasma membrane. The expressed pump was purified by affinity chromatography on calmodulin sepharose. The PMCA of transfected CHO cells promoted an increase of Ca2+ into the medium, after induction of Ca2+ release from the internal stores by activation of a purinergic receptor. An evident decrease of the activity of the endogenous sarcoplasmic reticulum Ca(2+)-ATPase pump was observed, probably related to the down-regulation of its expression. The cells overexpressing the PMCA pump had delayed recovery after trypsinization and plating. Their doubling time was, however, the same as CHO cells.

The absence of Emp24p, a component of ER-derived COPII-coated vesicles, causes a defect in transport of selected proteins to the Golgi

Emp24p is a type I transmembrane protein that is involved in secretory protein transport from the endoplasmic reticulum (ER) to the Golgi complex. A yeast mutant that lacks Emp24p (emp24 delta) is viable, but periplasmic invertase and the glycosylphosphatidyl-inositol-anchored plasma membrane protein Gas1p are delivered to the Golgi apparatus with reduced kinetics, whereas transport of alpha-factor, acid phosphatase and two vacuolar proteins is unaffected. Oligomerization and protease digestion studies of invertase suggest that the selective transport phenotype observed in the emp24 delta mutant is not due to a defect in protein folding or oligomerization. Consistent with a role in ER to Golgi transport, Emp24p is a component of COPII-coated, ER-derived transport vesicles that are isolated from a reconstituted in vitro budding reaction. We propose that Emp24p is involved in the sorting and/or concentration of a subset of secretory proteins into ER-derived transport vesicles.

Secretoneurin in bronchopulmonary carcinoids--immunohistochemical comparison with chromogranins A and B and secretogranin II

Ninety-nine classical and 11 atypical bronchopulmonary carcinoids were investigated immunohistochemically with an antibody against secretoneurin, a peptide proteolytically processed from secretogranin II (chromogranin C), as well as antibodies against chromogranin A and B and secretogranin II. Secretoneurin was immunolocalized in 86 tumours (78 classical and eight atypical carcinoids); secretogranin II was found in the same tumours in a similar distribution, whereas chromogranin A was present in all 100 and chromogranin B in 106 tumours investigated. Bronchopulmonary carcinoids are usually not associated with clinically or biochemically distinct syndromes. Although we found bronchial carcinoids with different immunohistochemical chromogranins/secretogranin patterns, no correlation with the biological behaviour of these tumours could be demonstrated.

Overlapping expression of immunohistochemical markers and synaptophysin mRNA in pheochromocytomas and adrenocortical carcinomas. Implications for the differential diagnosis of adrenal gland tumors

BACKGROUND

The differential diagnosis of cortical versus medullary tumors of the adrenal gland may be a problem in diagnostic pathology. Conflicting results have been reported about the distribution of various immunohistochemical markers in the normal as well as neoplastic adrenal cortex and medulla.

EXPERIMENTAL DESIGN

Archival, formaldehyde-fixed, and paraffin-embedded material comprising 27 adrenocortical carcinomas (ACC, meeting Weiss' histologic criteria), 28 pheochromocytomas (PCC), and adjacent nontumorous tissue (13 glands) were analyzed by immunogold-silver staining for the expression of polysialic acid (poly Sia), cytokeratins (CK), synaptophysin (SYN), chromogranin A (CrgA), somatostatin (SOM), calcitonin (CT), and the "adrenocortical marker" D11. Further, SYN mRNA expression was studied by nonradioactive in situ hybridization using digoxigenin-labeled oligonucleotide probes.

RESULTS

In the normal adrenal gland, poly Sia was exclusively detected in the medulla and in cortical nerves. In ACCs, SYN immunoreactivity was present in 23 of 27 tumors (85%), D11 was present in 22 of 27 (81%), poly Sia was present focally in 8 of 27 (29%), and CK was present in 7 of 27 (25%). Synthesis of SYN in ACCS was demonstrated by mRNA in situ hybridization. Immunoreactivity for CrgA, SOM, or CT was not detectable. No difference of the marker profiles was seen in the nine clinically hormone-producing (three androgen, five corticosteroid, one mineralocorticoid) ACCs compared with the clinically silent tumors. In PCCs, all 28 tumors were immunoreactive for poly Sia and SYN; CrgA was detectable in 26 of 28 (93%), CT was detectable in 6 of 28 (21%), and SOM was detectable in 2 of 28 (7%) tumors. Staining for D11 or CK was undetectable. By immunohistochemistry, no distinction was possible between the 4 clinically malignant, the 6 multiple endocrine neoplasia type 2A-associated, and the 18 sporadic benign PCCs.

CONCLUSIONS

Poly Sia of the neural cell adhesion molecule is consistently detected in normal adrenal medullary cells as well as in PCCs, and is occasionally focally expressed in ACCs. CrgA, CK, and D11 are reliable markers to immunohistochemically distinguish ACC from PCC. Immunoreactivity for SYN and detection of its mRNA in the majority of ACCs indicates the existence of tumor cells sharing both cortical and medullary features. Such focal neuroendocrine differentiation in ACCs can lead to confusion with PCCs.

Primary structure of the neuronal clathrin-associated protein auxilin and its expression in bacteria

The protein auxilin is a coat component of brain clathrin-coated vesicles. It interacts directly with the heavy chain of clathrin and supports its assembly into regular cages [Ahle, S. & Ungewickell, E. (1990) J. Cell Biol. 111, 19-29]. The combined open reading frames of three cow brain cDNA clones with a total of 4531 nucleotides predict a molecular mass of 99,504 Da for auxilin. The coding region is followed by a very long untranslated region of at least 1670 nucleotides. By Northern analysis, auxilin transcripts are found only in brain tissue. Auxilin is not related to any of the previously sequenced clathrin-binding proteins, but the region of positions 50-350 is 29% identical (similarity 56%) to the corresponding region of the actin-binding protein tensin from chicken fibroblasts. Recombinant auxilin expressed in and purified from bacteria by affinity chromatography is functional with respect to clathrin binding.

Re-excision of soft tissue sarcoma after inadequate initial operation

Between January 1988 and October 1993, 189 patients with soft tissue sarcoma of the extremities and trunk underwent surgery and since 1988, patients in whom the initial operation did not achieve safe margins underwent reoperation (67 of the 189). At re-excision an en block resection of the area with wide margins was achieved in 59 patients. Residual tumour was found in 30 specimens (45 per cent). Thirty-six patients received postoperative radiotherapy and/or chemotherapy. After a mean follow-up of 32 (range 1-69) months five patients (7 per cent) had local recurrence. In view of the high rate of local recurrence after local excision of soft tissue sarcoma (70-90 per cent), primary re-excision is indicated after an inadequate initial operation.

Histological and ultrastructural findings in chloroquine-induced cardiomyopathy

Light microscopic and ultrastructural findings in patients suffering from chloroquine-induced cardiomyopathy are reviewed. Based on our own observations in an autopsy case, functional and morphological similarities between chloroquine effects and hereditary lysosomal storage diseases are discussed.

[Fatal vacuolar cardiomyopathy in chronic chloroquine drug treatment]

Clinical and morphological findings recorded in an 81-year-old woman patient with a 45-year history of rheumatoid arthritis treated with long-term chloroquine therapy are reported. The cause of death was low cardiac output syndrome, which upon autopsy and postmortem toxicological analyses was classified as vacuolar chloroquine-induced cardiomyopathy. The pathogenesis and the morphological and clinical characteristics of cardiotoxic effects of chloroquine are reviewed.

[Fatal generalized AA amyloidosis in mutilating psoriatic arthropathy]

Autopsy findings are reported of a 51-year-old female patient with a 40-year history of mutilating psoriatic arthritis. As a result of this disease the patient developed reactive amyloidosis (AA-type) with generalized vascular involvement, amyloid kidneys and unusual amyloid goitre. The cause of death was ischaemic left ventricular failure due to massive amyloid deposits in the coronary arteries and left ventricular hypertrophy, the latter resulting from renal hypertension. Thus, amyloidosis and ischaemic heart disease were late complications of the underlying inflammatory disease.

[Lymphoepithelial carcinoma of the thyroid gland. A thyroid gland carcinoma with thymus-like differentiation]

An example of lymphoepithelial carcinoma of the thyroid is reported, which was first described 10 years ago and has not as yet been documented in the German literature. This tumour is morphologically identical to the lymphoepithelioma of the nasopharynx. In contrast to neoplasms of such morphology occurring in a variety of other organs, the acronym CASTLE--for carcinoma showing thymus-like differentiation--has been proposed by Chan and Rosai for lymphoepithelioma-like carcinomas of the thyroid gland. In this paper, the aforenamed authors' concept of the histogenesis of thyroid tumours with thymic differentiation is presented.

Detection of RET proto-oncogene point mutations in paraffin-embedded pheochromocytoma specimens by nonradioactive single-strand conformation polymorphism analysis and direct sequencing

The suitability of formalin-fixed and paraffin-embedded tumor material was evaluated for molecular analysis of the RET proto-oncogene. We analyzed exons 10, 11, and 16 for point mutations in seven sporadic and six multiple endocrine neoplasia (MEN) 2A-associated pheochromocytomas by a nonradioactive single-strand conformation polymorphism assay followed by nonradioactive direct sequencing of PCR-amplified DNA using an automated DNA sequencer. All MEN 2A-associated pheochromocytomas contained a heterozygous missense germline mutation within cystine codons of the cysteine-rich extracellular domain encoded by exons 10 and 11. Mutations were located in codon 619 (TGC-->TCC; Cys-->Ser) in one, in codon 635 (TGC-->CGC; Cys--Arg) in three, and in codon 635 (TGC-->TAC; Cys-->Tyr) in two pheochromocytomas. No tumor-specific (somatic) mutations were detected in exons 10, 11, and 16 of the sporadic pheochromocytomas. These data support recent findings that germline point mutations that are clustered in distinct cysteine codons of the RET proto-oncogene are involved in the neoplastic phenotype of the MEN 2A syndrome. Our results demonstrate that both nonradioactive single-strand conformation polymorphism and direct sequencing are suitable methods to detect single base substitutions in DNA extracted from archival material.

[Leiomyosarcoma in the thyroid gland--primary tumor or metastasis?]

In a 69-year-old female patient a moderately pleomorphic spindle-cell thyroid tumour measuring 5 cm in diameter was initially misinterpreted as primary anaplastic thyroid carcinoma. During clinical investigations to elucidate the cause of severe anaemia, 17 months later an ulcerated duodenal leiomyosarcoma was detected and removed by duodenopancreatectomy. Reevaluation of the thyroid nodule led to revision of the initial diagnosis to metastatic leiomyosarcoma. Six months later the patient died from cerebral stroke. Autopsy findings confirmed the diagnosis of primary leiomyosarcoma of the duodenum with initial manifestation as thyroid metastasis.

Renal parenchymal malakoplakia: ultrastructural findings in different stages of morphogenesis

Light microscopic and ultrastructural findings in five cases of renal parenchymal malakoplakia detected in renal biopsy specimens (four cases) or observed at autopsy (one case) are reported. The spectrum of ultrastructural changes ranging from lamellar and microvesicular phagolysosomal inclusions arranged in a biphasic pattern to fully developed Michaelis-Gutmann bodies is described. In three of the biopsy cases the lesions appeared to represent early stages of malakoplakia lacking classic Michaelis-Gutmann bodies. Especially in this phase of disease, ultrastructural investigation can distinguish between this condition and other histiocytic interstitial renal processes. The findings show that focal cytoplasmic degeneration and autophagolysosomal processes observed in macrophages could precede the disturbance in the process of bacterial breakdown that is responsible for the peculiar granuloma-like inflammatory histiocytic reaction.

[Positive cytokeratin results in malignant melanoma. Pitfall in differential immunohistologic diagnosis of occult neoplasms]

Immunohistology was performed on 84 paraffin-embedded surgical specimens of malignant melanomas (MM) from a total of 74 patients. The series consisted of 62 cutaneous primary tumors and 22 (partly selected) secondary manifestations (9 cutaneous recurrences and 13 metastases). In 4 patients with lymph node MM infiltrates, clinical investigations failed to identify a cutaneous primary tumor. In the primary and secondary manifestations respectively, the following proportions of immunohistologically positive cases were recorded: vimentin 100% each, S100-protein 95% each, NSE 87%/77%, HMB45 97%/64%, NKI/C3 97%/95%, cytokeratins (CK) (antibodies KL1, CAM5.2 and 35 beta H11) 0%/23%. Four of the 5 CK-positive lesions belonged to 3 patients in whom MM had occurred at first or exclusively as a lymph node infiltration. These findings confirm the results of other authors who report that positive staining results for CK can be expected in paraffin sections of secondary manifestations of MM in up to 10% of cases in large, nonselected series. This phenomenon appears, however, to be rare in primary cutaneous MM.

[Malignant meningeal "histiocytosis"]

Two cases of patients with unusual pleomorphic tumors in the meninges are reported. Histologically and immunohistologically, the tumor cells may be histiocytic in appearance. Computed tomography and magnetic resonance imaging scans, however, revealed no lesions in the parenchyma or in the meninges. The cytological examination of the cerebrospinal fluid revealed only a light lymphocytic reaction without tumor cells in both cases and thus led to misinterpretations as meningoencephalitis. One patient presented psychiatric symptoms. Related clinical problems and the possible histogenesis of the tumors are discussed.

[Multiple endocrine neoplasia type 1 (MEN 1). Molecular genetics, morphology and prognosis]

The syndrome of multiple endocrine neoplasia type 1 (MEN 1) is an autosomal dominant tumour disease of the neuroendocrine system with manifestations in the parathyroids, pancreas, duodenum and pituitary gland and rarely also in the stomach and thymus. Recently, the MEN 1 gene locus has been mapped to the long arm of chromosome 11. This gene most likely belongs to the tumour suppressor genes, the allelic loss of which causes tumour development. The pancreatic and duodenal tumours may metastasize, but usually have a low malignant potential. Clinically, most MEN 1 patients present between the age of 20 and 35 with hyperparathyroidism and/or Zollinger-Ellison syndrome.

[Primary hemorrhagic spindle cell tumor of the lymph node with amianthoid structures. Case report and review of the literature]

An example of a benign haemorrhagic spindle cell tumour of the lymph node (synonym: intranodal myofibroblastoma) is presented, which was first described 5 years ago and has not as yet been documented in the German literature. This rare benign mesenchymal neoplasm of the lymph node occurs almost exclusively in the inguinal region. Diagnostic criteria include its composition of myofibroblastic cells (with immunoreactivity for vimentin and actin), which may show nuclear palisading, the presence of peripheral haemorrhage zones and the occurrence of characteristic amianthoid structures, which have the ultrastructural appearance of dense meshworks of collagen fibers. Knowledge of this tumour entity is important for differential diagnosis of primary and secondary malignant mesenchymal neoplasias of the lymph node.