Localization of a highly specific neuronal protein,serotonin binding protein,in thyroid parafollicular cells

A highly specific serotonin binding protein (SBP) has been found in serotonergic neurons in both brain and gut. This protein has an extremely high affinity for serotonin and may be a storage protein. Serotonin is found in many endocrine cells, including parafollicular cells of the sheep thyroid, as well as in neurons. SBP is also present in sheep thyroid. The present study was done to localize the protein in the gland. Thyroid glands were divided into five segments. Concentrations of serotonin and SBP, as well as parafollicular cell volume were measured in each. Serotonin was assayed by enzymatic conversion to melatonin using tritiated S-adenosylmethionine. SBP was assayed by molecular sieve chromatography on sephadex G-50. The relative volume of parafollicular cells was obtained by stereological analysis of electron micrographs. Experiments were also done to demonstrate these cells by histofluorescence and radioautography following incubation with tritiated 5-hydroxytryptophan. Good correlations were found between serotonin and SBP concentrations, and parafollicular cell volume. These peaked in the rostro-central portion of the gland and were minimal at the poles. We conclude that thyroid SBP is probably localized in parafollicular cells.     

Dielectric properties of a combined main-chain/side-chain liquid-crystalline polymer

The dielectric relaxation properties of a combined main-chain/side-chain liquid-crystalline polymer were investigated. It was found that the rotation of the side chain about the main chain (δ-process) is not as strongly restricted as in side-chain liquid-crystalline polymers. This is attributed to the facts that the side chain is attached to the flexible spacer within the chain backbone and that the concentration of the side chains is comparatively small. Two low-temperature relaxation processes were observed to occur in the glassy smectic and the crystalline state. They are attributed to intramolecular motions with in the mesogenic groups.     

Pathologische Myophosphorylasereaktion bei der malignen Hyperthermie

Zusammenfassung Die Myophosphorylasereaktion (MPR) zeigt bei der malignen Hyperthermie (MH) charakteristische Veränderungen, die in Minutenschnelle entstehen: 1.) eine allgemein stark abgeschwächte Reaktion, 2.) zahlreiche negativ reagierende Fasern, 3.) häufig fleck- und/oder streifenförmig abgeschwächt oder negativ reagierende und streifenförmig verstärkt reagierende Faserabschnitte mit relativ engen Sarkomerenabständen (Zeichen der Hyperkontraktion). Diese morphologischen Befunde mit den kennzeichnenden Streifenfasern sind offenbar für das MH-Syndrom spezifisch! Wichtig ist, daß die derart veränderten Muskelfasern in der Regel bei den anderen Färbungen und Reaktionen unauffällig sind.Wir sahen diese pathologische MPR bei 5 verstorbenen Patienten, einmal unabhängig von einer Anästhesie nach einem Marsch, und bei 19 Schweinen, davon 18mal nach dem Halothantest und einmal bei einem Versuchstier mit gesicherter MH. Sie fehlte bei Schweinen mit negativer Halothanreaktivität und vor dem Halothantest und bei vielen, sehr verschiedenen gesunden und kranken Kontroll- und Vergleichsfällen aus dem bioptischen und autoptischen Untersuchungsgut. Die MPR erlaubt den sicheren Nachweis einer inszenierten oder abgelaufenen MH und damit eine Aufklärung rätselhafter oder scheinbar klarer Todesfälle während oder nach der Narkose oder allgemein nach Streß (human stress syndrome), von denen sicher viele der klinischen Aufmerksamkeit und den üblichen morphologischen Untersuchungsmethoden entgehen. Sie ist nicht geeignet, potentielle Opfer zu erkennen.Mit Unterstützung des Ministeriums f. Gesundheitswesen (HFR Schwangerschaft und frühkindliche Entwicklung, FR Genetische Defekte). Auszugsweise vorgetragen auf dem IV. Internationalen Myologie-Kolloquium in Jena 1984     

Risk Factors and Management of Leukopenia After Kidney Transplantation: A Single-Center Experience

BackgroundLeukopenia is a common complication after kidney transplantation. The etiology is multifactorial, with medication adverse effects and cytomegalovirus infection as main causes. Optimal strategies to prevent or treat posttransplant leukopenia remain unknown. We aimed to identify risk factors for leukopenia and to investigate the benefit of switching the immunosuppressive therapy to hydrocortisone as a continuous infusion.MethodsWe retrospectively evaluated all patients with leukopenia after kidney transplantation between 2007 and 2017 at our center relative to age- and sex-matched controls.ResultsLeukopenia was associated with the degree of rejection therapy before leukopenia, the immunosuppressive therapy before transplantation, and an induction therapy with rabbit antithymocyte globulin. Patients with leukopenia exhibited increased mortality, an increased incidence of bacterial and viral infections, and more acute rejections. Switching to hydrocortisone as a continuous infusion in patients with severe leukopenia decreased the duration of leukopenia and the incidence of subsequent viral infections, especially with cytomegalovirus.ConclusionLeukopenia is a risk factor for infectious complications and mortality, and it is associated with acute rejection. Switching immunosuppressive therapy to hydrocortisone as a continuous infusion is a safe approach to reduce the duration of leukopenia and the incidence of viral infections.     

Radiologische Interventionen bei Schlaganfall

Notfall + Rettungsmedizin - In den letzten Jahren hat sich die mechanische Thrombektomie mit Stent-Retrievern als wichtiger Bestandteil der Behandlung des ischämischen Schlaganfalls etabliert....     

Stellenwert von Computertomographie und Magnetresonanztomographie bei der Diagnostik von Malignomen der Mundh?hle und des Oropharynx

Problem: There is a lack of clear criteria for the use of MR and CT in the diagnosis of head and neck cancer – some of it is even contradictory. The results of this study should lead to the establishment of more clear criteria. Patients: 165 patients suffering from head and neck tumors were subjected to a total of 463 CT and 197 MRI examinations. Results: The CT and MRI staging corresponded in 67% and 60% of the oropharynx tumors, respectively, with the clinical findings. In the case of oral cavity tumors, the clinical TNM stages were identical with CT and MRI results in 50% and 43% of cases, respectively. In the case of lymphatic node staging, the frequency of error was slightly higher using MRI, at 27%, compared with the CT rate of 22%. In the evaluation of cervical lymphatic nodes, CT proved to be more sensitive attaining 78% compared to the MRI rate of 69%. Conclusion: The results provide clear indications as to the MRI and CT examinations. Primary preoperative screening and post-therapeutic aftercare should be assessed using CT, as should lymphatic node diagnosis in the neck area. In the case of special problems such as, for example, the relevant bone and periostium infiltration, MR should be considered as a supplementary examination at a second stage.      

Flecked chorioretinopathy associated with Birt-Hogg-Dubé syndrome

Background: BirtHogg-Dubé's syndrome is a rare skin disease characterized by multiple trichofibromas of the skin and polyps of the intestine. Ophthalmologic manifestations associated with the syndrome have not been reported in detail. Case reports and methods: Two siblings suffering from Birt-Hogg-Dubé syndrome were examined clinically. Electrooculography and electroretinography were performed according to international standards. Color fundus photographs were taken as well as fluorescein angiograms. The two patients showed multiple perifollicular fibromas and trichodiscomas of the skin of the head. Funduscopy and fluorescein angiography revealed a flecked chorioretinopathy in one patient with progressive constriction of visual fields and severely reduced electroretinographic responses. Ophthalmoscopy in his sister showed peripheral pigmentary changes with only minor functional abnormalities. Conclusion: These findings suggest that Birt-Hogg-Dubé syndrome may be associated with a progressive flecked chorioretinopathy with constricted visual fields and that patients with the syndrome should undergo ophthalmological examination.     

Cationic-amphiphilic arpromidine-derived guanidines and a histamine trifluoromethyl-toluidide derivative may activate pertussis toxin-sensitive G-proteins by a receptor-independent mechanism

Formyl peptides activate superoxide anion (O₂ ^–) formation in human neutrophils and in HL-60 cells via pertussis toxin (PTX)-sensitive guanine nucleotide-binding proteins (G-proteins), and histamine (HA) mediates inhibition of O₂ ^– formation via H₂-receptors. We have studied the effects of lipophilic arpromidine-derived guanidines, which are potent, full H₂-receptor agonists in the guinea pig atrium, on O₂ ^– formation and on activation of G-proteins in HL-60 membranes and on purified G-proteins. We have also studied the effects of a HA trifluoromethyl-toluidide derivative (HTMT), a cationic-amphiphilic HA derivative which activates O₂ ^– formation in HL-60 cells through a mechanism which is independent of known HA receptor subtypes, on G-protein activation. Guanidines, at concentrations, up to 30 mol/l inhibited and, at concentrations above 30 mol/l, enhanced formyl peptide-induce O₂ ^– formation in neutrophils. In HL-60 cells, guanidines per se activated O₂ ^– formation. The stimulatory effects of guanidines on O₂ ^– formation were not inhibited by H₁- or H₂-receptor antagonists. In HL-60 membranes, guanidines and HTMT, activated high-affinity GTPase in a PTX-sensitive manner. These substances also increased GTP hydrolysis effected by transducin and G_i/G_o-proteins. Our data suggest that lipophilic guanidines and HTMT may act as receptor-independent activators of PTX-sensitive G-proteins, resulting in stimulation of O ₂ ^– formation.     

Multileafkollimator: Erweiterte Qualit?tssicherung an einem GE-Linearbeschleuniger

Hintergrund: Ein Multileafkollimator stellt durch die Vielzahl der Lamellen sehr viel höhere Ansprüche an die Konstanzprüfverfahren als ein konventionelles Blendensystem. Zur täglichen Kontrolle der Lamellenpositionierung wird ein Qualitssicherungskonzept vorgestellt. Methode: Zwei Feldkonfigurationen, die bei maximaler Öffnung der Blockblenden sowohl maximale Öffnung als auch "Overtravel" einzelner Lamellen enthalten, werden in täglichem Wechsel online vom Verifikationssystem zum Linearbeschleuniger übertragen. Im Lichtfeld des Linearbeschleunigers erfolgt eine visuelle Kontrolle der Lamellenpositionen mit Hilfe eines speziellen Prüfkörpers. Abschließend wird die Lamellenpositionierung mittels eines Electronic-Portal-Imaging-Systems dokumentiert und nach Überlagerung eines Gitters mit einer Referenzaufnahme verglichen. Ergebnisse: Die Methode stellt eine schnelle und effektive Möglichkeit dar, die Funktionsfähigkeit des gesamten Systems durch Simulation des "Routinebetriebs" zu überprüfen. Schlußfolgerung: Der Arbeits- und Zeitaufwand für die Qualitätssicherung an einem Multileafkollimator unterscheidet sich nur unwesentlich von dem eines konventionellen Blendensystems. Background: In comparison to a conventional collimator, a multileaf collimator demands a great deal of quality assurance procedures due to its large number of leaves. A concept for daily quality assurance is presented, mainly concerning the positioning accuracy of the leaves. Material and Methods: Two leaf configurations including maximal opening as well as overtravel of single leaves, at a maximal opening of the jaws, are transmitted online in daily exchange from our record- and verify system to the linac. Aiming at a special test phantom a visual control of the positioning accuracy is performed. The leaf positioning is documented by an electronic portal imaging system and is compared with a reference shot by superposition of a grid. Results: This method of quality assurance offers a fast and effective possibility to guarantee the proper function of the whole system by simulating the routine treatment situation. Conclusions: Compared to a conventional collimator only a slightly greater workload is needed for quality assurance of a multileaf collimator.