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Biomedical subjects

J Laissue

Publications and source records attributed to J Laissue.

At least 19 recordsLinked to original sources
PubMed1992

Enteropathy-associated T-cell lymphoma in a renal transplant patient with evidence of Epstein-Barr virus involvement.

The clinical and histological findings in a 54-year-old patient with enteropathy-associated T-cell lymphoma (EATL) occurring 18 years after renal transplantation are presented. Ten years after adult-onset coeliac disease the patient developed medium to large T-cell non-Hodgkin's lymphoma of the small intestine. Epstein-Barr virus (EBV) genome was detected by polymerase chain reaction in the lymphoma tissue and localized via Epstein-Barr virus RNAs in situ hybridization to some of the tumour cells. This is the first case report of EBV-positive EATL occurring in the setting of immunosuppression.

Base Sequence↗
PubMed1992

Preferential location of somatostatin receptors in germinal centers of human gut lymphoid tissue.

Somatostatin receptors were evaluated in four human gut-associated lymphoid tissues (palatine tonsils, ileal Peyer patches, vermiform appendix, and colonic solitary lymphatic follicles) using receptor autoradiography on tissue sections incubated with 125I[Tyr3]octreotide. All four tissues were somatostatin-receptor positive; the receptors were preferentially located in the germinal centers, with the luminal part of the center more strongly labeled than the basal part. The corona of the follicles and the primary follicles without germinal centers did not display somatostatin receptors. The receptors were of high affinity (Kd = 1.3 +/- 0.6 nmol/L) and specific for somatostatin. Displacement by nanomolar concentrations of somatostatin 14, somatostatin 28, and octreotide was observed, as was guanosine triphosphate dependency. The gastrointestinal mucosa and the plexus submucosus and myentericus also contained somatostatin receptors. These data strongly suggest that the germinal centers of the gut-associated lymphoid tissue are a site of action of somatostatin. It possibly mediates antiproliferative effects and inhibits immunoglobulin synthesis in the activated lymphoid cells. The human gut represents a multifaceted target for somatostatin action, in which at least three different tissues (mucosa, nerve plexus, and lymphoid tissue) are involved.

Humans↗
PubMed1992

Somatostatin receptors in human cancer: incidence, characteristics, functional correlates and clinical implications.

Somatostatin receptors (SS-R) have been identified in membrane homogenates or tissue sections from several hundred tumors. SS-R were found in most neuroendocrine tumors, i.e. GH and TSH producing pituitary tumors, endocrine gastroenteropancreatic (GEP) tumors, paragangliomas, pheochromocytomas, medullary thyroid carcinomas (MTC) and small cell lung carcinomas. SS-R were also expressed in a majority of malignant lymphomas, in several brain tumors (all meningiomas, most astrocytomas) and in breast tumors. The majority of tumors expressing SS-R are rather differentiated (i.e. astrocytomas vs glioblastomas), but exceptions exist (high grade malignant lymphomas). An inverse relationship exists between SS-R and receptors for epidermal growth factor (EGF-R) incidence in lung tumors, glial tumors and most breast tumors, whereas meningiomas express simultaneously both receptors. A minority of tumors (ovarian tumors, MTC, insulinomas) express a subtype of SS-R, characterized by low affinity for the octapeptide SS analog octreotide. The function mediated by SS-R in human tumors may differ according to the tumor type. SS-R in pituitary and GEP tumor mediate hormone secretion inhibition with, in addition, possibly some antiproliferative effects. In meningiomas, however, activation of SS-R inhibits forskolin-stimulated adenylate cyclase activity, and weakly stimulates proliferation. Whereas SS-R seem to mediate antiproliferative effects in animal models and cell lines of lymphomas, breast and lung tumors, such an effect has not yet been convincingly documented in human primary tumors. The clinical implications of the presence of SS-R in tumors are manyfold: (1) as a predictive marker for efficient therapy with octreotide in pituitary and GEP tumors; (2) as a diagnostic marker: for pathobiochemical classification of tumors, using in vitro detection methods; for clinical evaluation using in vivo scanning techniques; (3) as a prognostic marker; and (4) as a potential radiotherapeutic target.

Animals↗
PubMed1992

Immunohistochemical characterization of the human endolymphatic sac and its associated cell populations.

The use of monoclonal and polyclonal antibodies as specific markers for the localization of tissue constituents in situ allows the characterization of cells according to their state of differentiation and the detection of cellular antigens related to the function of cells and tissues. Our studies focus on the immunohistochemical characterization of the human endolymphatic sac (ES) and its associated cell populations. A panel of 37 monoclonal and polyclonal antibodies were used on frozen sections and fixed material from 64 ES of 32 persons without any clinically known inner ear disorders. The ES were removed at the time of autopsy; case histories were available. The results of our studies on the extraosseous part of the human ES support the assumption that the epithelium is metabolically active and capable of both secretion and absorption. The reactivity of the epithelial cells with antibodies against neuron specific enolase, chromogranin and somatostatin, respectively, implies a paracrine activity of the ES. Further results obtained with antibodies specific for cells of the immune system indicate a possible role of the human ES in the inner ear immune defence and a functional relationship of the ES to the common mucosa-associated immune system.

Adolescent↗
PubMed1992

Functional morphology of the human endolymphatic sac. A review.

Modern immunohistochemical methods allow a functional characterization of the human endolymphatic sac (ES) and its associated cell populations. The currently available immunohistochemical data on the extraosseous part of the human ES support the assumption that the epithelium is metabolically active and capable of both secretion and absorption. The reactivity of some epithelial cells with antibodies against neuroendocrine antigens implies a paracrine activity of the human ES. Further results provide evidence for a possible role of the human ES in inner ear immune defense and indicate a putative functional relationship of the human ES to the common mucosa-associated immune system.

Endolymphatic Sac↗
PubMed1990

Somatostatin receptor incidence and distribution in breast cancer using receptor autoradiography: relationship to EGF receptors.

Somatostatin receptors (SS-R) were measured with in vitro receptor autoradiography using the SS analog 125I-[Tyr3]-SMS 201-995 as radioligand in 342 breast-tumor samples. In a group of 158 "small" tumor samples (mean section surface: 14 mm2 +/- 0.4; mean +/- SEM), 34 tumors (21%) were SS-R positive. In a group of 72 "large" tumor samples (mean size: 180 mm2 +/- 8; mean +/- SEM), 33 tumors (46%) were SS-R positive. In this second group, more than half of the tumors had a non-homogeneous distribution of SS-R, i.e., tumor regions within SS-R positive tumors were SS-R negative. In a group of 48 additional patients, we could show that primaries and their metastases, or double primaries from right and left breasts, or 2 primaries resected consecutively, could both occasionally be SS-R positive. Finally, in 71 SS-R-positive primary tumors, 18 tumor samples were found to have simultaneously Epidermal Growth Factor receptors (EGF-R); in 12 of these 18 cases, the 2 receptor types were not topographically overlapping. Whereas SS-R were located on tumor tissue, EGF-R were often seen on adjacent normal lobules and ducts. These results show that a subgroup of breast tumors contain SS-R, in several cases non-homogeneously distributed. Their location does not coincide with that of EGF-R. Metastasis of SS-R-positive primaries may be SS-R-positive, as are sometimes second primaries. For evaluation of SS-R incidence and distribution, autoradiography is of advantage, specially if it is performed on large tumor samples, since it allows precise identification of the tissue elements containing these receptors.

Amino Acid Sequence↗
PubMed1989

Germinal center kinetics in lymph nodes of primed mice stimulated with complexed as opposed to free antigen.

Primed mice with low titers of circulating tetanus antitoxin (AB) were stimulated via the hind footpads with either fluid tetanus toxoid alone (AG) to create in vivo complexes in AG excess, or the same dose of toxoid complexed at equivalence with isologous antibody (AB-AG CPX), to have in vivo complexes in AB excess. All experimental animals reacted with three topically distinct consecutive waves of enhanced proliferative activity in popliteal lymph nodes, i.e., in the T-zone (peak on day 2), in the medullary area, the main site of plasmocytopoiesis (day 3), and in lymphoid follicles (day 5-6). Maximum serum AB titers following injection of AG-AB CPX were only about 25% of those found in animals boosted with AG alone. This suppressive effect was best reflected in a comparable reduction in plasmocytopoiesis, and to an lesser extent in the proliferative activity within the T-zone, and not at all in the overall magnitude of germinal center formation and/or expansion. However, the patterns of germinal center kinetics differed markedly between the two groups: a high sharp peak of development on day 5, followed by a marked drop on day 6 characterized the response in mice given AG alone, and a broad peak around day 6 that of those receiving AG-AB CPX. These differences could not adequately be accounted for by variations in centroblast/centrocyte proliferation rate vs. pycnotic indices, so that different patterns of lymphoid cell emigration from the centers may be considered. The results suggest that immune complexes, fixed on follicular dendritic cells, with different antigen-to-antibody ratios have divergent effects on the development and kinetics of germinal centers, the principal sites of memory B cell generation.

Animals↗
PubMed1988

[Renal manifestations of sarcoidosis].

Renal manifestations of sarcoidosis are rare. In addition to calcium nephropathy, granulomatous interstitial nephritis and glomerulo-nephritis (GN) account for most cases. The latter two manifestations are described in 4 patients and in a detailed review of the literature. In comparison to a nonselected population of sarcoidosis patients, granulomatous interstitial nephritis is found more frequently in male patients above 40 years of age; it is associated more frequently with other extrathoracic manifestations of sarcoidosis; and it causes renal insufficiency of varying degree, which is at least partially reversible with steroid therapy. Predominant findings are silent microhematuria, sterile pyuria, mild proteinuria and a variety of tubular functional disorders. Glomerulonephritis (39 observations) has been described with increasing frequency in sarcoidosis. Because of the well known immunological abnormalities of sarcoidosis, frequent association of sarcoidosis with GN could be expected but this association has not yet been proven statistically. Sarcoidosis-associated GN includes a variety of histological forms, viz. membranous, proliferative and sclerosing GN. Glomerulonephritis may appear before sarcoidosis. Conversely, both diseases may appear simultaneously, or GN may follow all other manifestations of sarcoidosis with a latency period of many years.

Aged↗
PubMed1987

[Acquired cystic renal changes--a clinically relevant problem in long-term dialysis].

While dialysis patients survive renal failure for years and even decades, multiple morphologic alterations take place in their kidneys. One of these (so to speak) "postmortem" changes is the formation of secondary renal cysts. A patient with end stage renal failure due to amyloidosis is described who was dialysed at home for 9 years. Intravenous pyelography and renal biopsy in the predialysis period likewise documented the presence of amyloidosis and the absence of cystic disease. Ultrasonography of both kidneys, a suspicious increase in hematocrit and the autopsy finding of numerous large cysts also showed the presence of acquired cystic disease. The frequency and complications of this newly recognized disease in longterm dialysed patients are discussed. Recommendations are given concerning follow-up of these patients, with a view to early detection of tumor development within the cysts.

Amyloidosis↗
PubMed1986

Somatostatin (somatostatinlike) immunoreactive cells in the human inner ear.

Certain epithelia of the human inner ear and human endolymphatic sac display somatostatin and/or somatostatin-like immunoreactivity. Histologic sections from 13 human temporal bones and from 15 endolymphatic sacs were studied using the unlabeled antibody peroxidase-antiperoxidase technique. The somatostatin and/or somatostatin-like immunoreactive cells were located exclusively in the covering epithelium of the spiral prominence and in the epithelium of the intermediate and rugosal part of the endolymphatic sac. In the epithelium of the spiral prominence and endolymphatic sac, secretory granules of the same size and appearance as those of intestinal or pancreatic somatostatin-producing cells were demonstrated ultrastructurally. The findings are consistent with a local exocrine, paracrine, and/or endocrine system of the inner ear.

Cytoplasmic Granules↗
PubMed1982

[Chronic defibrination syndrome and thrombocytopenia in splenic hamartoma (splenoma)].

In a 41-year-old woman who had suffered from hypofibrinogenemia, thrombocytopenia, leukopenia and splenomegaly for several years a causative hamartoma of the spleen (splenoma) was removed surgically. The results of a preoperative therapeutic trial with heparin, the marked accumulation of 125I-activity in the splenoma following intravenous injection of radioiodinated fibrinogen, the immunohistochemical demonstration of extensive fibrinogen deposits in the splenoma, and normalization of fibrinogen levels and blood cell counts after surgery point to the pathogenetic role of this rare splenic tumor. The salient clinical and pathological features of 41 splenoma cases in the literature are briefly reviewed. Hematologic signs were observed in only 9 splenoma patients.

Adult↗
PubMed1982

[Hemangio-endothelioma of the liver (case report) (author's transl)].

The infantile hemangio-endothelioma (IHE) of the liver, a rare neoplasm, may lead the clinician and the surgeon to suspect the presence of a malignant tumor, whereas histologic examination often reveals a benign condition; our case report illustrates this discrepancy in a 3 1/2-month-old girl suffering from multiple nodules in the liver. Conservative steroid treatment resulted in a marked reduction in tumor size; the girl is in good health more than two years after diagnosis. More than 80% of hepatic IHE are diagnosed during the first six months of life. Hepatomegaly, congestive heart failure and hemangiomas of the skin combine to the classic symptomatic triad. Since the mortality is high in untreated cases, early diagnosis is of importance. IHE may regress spontaneously. Therefore, conservative therapy, such as steroid medication and treatment of the secondary, tumor-induced complications appear indicated. Alternatively, embolization and/or resection of the tumor may be considered. Signs of cardiac or hepatic insufficiency at diagnosis and a low degree of histologic differentiation are of unfavorable prognostic significance.

Biopsy↗
PubMed1981

[Megalocytic interstitial nephritis. A contribution to the differential diagnosis of the large insufficient kidney].

After a female patient had presented with advanced renal failure, bilateral enormous increase in kidney size radiologically, urinary tract infection (E. coli) and septicemia, autopsy disclosed megalocytic interstitial nephritis (MIN). Clinical and pathological differentiation from renal parenchymal malakoplakia (RPM) is discussed. A literature survey of 15 cases of MIN and 35 observations of RPM points to certain differences between the two entities, i.e. an increased incidence of bilateral pathology in MIN, mor frequent extrarenal localizations in RPM, absent Michaelis-Gutmann bodies and a predominantly cortical distribution in MIN. The similarities, however, suggest that the two conditions might represent different stages of one and the same disease process.

Diagnosis, Differential↗
PubMed1979

[Intravascular uterine leiomyomatosis].

Intravascular (intravenous) leiomyomatosis is a rare uterine neoplasm. The unusual growth and extension of histologically benign smooth muscle tumors in vascular channels of uterus and pelvis are cardinal features of the disease. The course of the affection has been benign in the majority of the cases reported in the literature. Clinical and pathologic aspects are briefly evaluated in the context of an example of intravascular leiomyomatosis in a 30-year-old woman.

Adult↗