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81.
Zusammenfassung Es werden elektronenmikroskopische Beobachtungen zur Lokalisation und zur Feinstruktur der Glykolipideinschlüsse in verschiedenen inneren Organen bei Morbus Fabry berichtet. Die intrazellulÄren und extrazellulÄren Einschlüsse bestehen aus vielschichtig lamellÄren Membransystemen in konzentrischer und exzentrischer sowie in stapeiförmiger paralleler Anordnung. Diese lamellÄre Anordnung ist charakteristisch für flüssigkristalline Phasen von Phospholipid-Wasser-Systemen. Erstmalig werden ultrastrukturelle Befunde an den inneren Organen einer erkrankten Frau mitgeteilt. Demzufolge lassen sich bei heterozygoten Frauen gleiche Glykolipidablagerungen wie bei homozygoten MÄnnern nachweisen. Die Beziehung der Glykolipideinschlüsse zu den Lysosomen wird erörtert.
Electron microscopic observations in internal organs in morbus fabry
Summary Electron microscopic findings are reported on the localization and fine structure of glycolipid inclusions in different organs (heart, kidney, lymph nodes, arterial blood vessels, pancreas) in Fabry's disease in a female. The intracellular and extracellular inclusions were made up of multilamellar membraneous systems in concentric, excentric, and parallel arrangement. This fine structure is characteristic of liquid-crystalline phases of phospholipid-water systems.The same type of inclusions are found in the internal organs of heterozygotic women as in homozygotic men. The relationship between the glycolipid inclusions and the lysosomes is discussed.
Herrn Prof. Dr. F. Bolck, Direktor des Pathologischen Instituts der Friedrich-Schiller-UniversitÄt Jena, zum 60. Geburtstag gewidmet.  相似文献   
82.
Zusammenfassung Die Beeinflussung der BSP-Kinetik durch Zusätze von Albumin zur Injektionslösung wurde geprüft. Bei einer Dosierung von 5 mg BSP pro kg Körpergewicht bleibt die Eliminationshalbwertzeit bis zu einem BSP-Albuminverhältnis von 1:10 (w/w) unverändert, nach größeren Albumingaben ist sie signifikant verlängert.F.H. Dost zum 65. Geburtstag zugeeignet  相似文献   
83.
Diacylated (e.g. MALP-2) and triacylated (Pam(3)Cys derivatives) lipopeptides, deriving from the N-terminal moiety of respectively mycoplasmal and E. coli lipoproteins, are powerful adjuvants recognized by Toll-like receptors (TLR) which have been used successfully to trigger cell activation and immune responses. To design liposome-based vaccination constructs in which Th and CTL epitopes are conjugated to synthetic lipopeptide analogues anchored into the bilayers of the vesicles, the peptide moieties of the lipopeptides were functionalized with thiol-reactive groups, such as maleimide (Mal) or bromoacetyl, incorporated into liposomes and reacted with thiol carrying peptide epitopes. Because dendritic cells (DCs) play a key role as antigen-presenting cells in immune responses, in the present study we have evaluated the impact of the functionalization of lipopeptide analogues Pam(2)CAG, Pam(3)CAG and Ol(3)GAG on the phenotypic maturation of human monocyte-derived DCs. The intrinsic cellular activities of the lipopeptide analogues incorporated into liposomes were monitored, in vitro, by measuring the up-regulation of the cell-surface markers CD80, CD83, CD86 and HLA-DR. We found that in some cases their functionalization with thiol-reactive groups led to a loss of activity. The stimulatory potency can be ranked in the following order: Pam(3)CAG>/=Pam(2)CAG-Mal-Th approximately Pam(2)CAG-Mal>Pam(3)CAG-Mal-Th (where Th is a HS-peptide) and no appreciable activity was detected for Pam(3)CAG-Mal, Ol(3)CAG-Mal and Ol(3)CAG-Mal-Th. Our findings indicate that subtle modifications in the peptide moiety of lipopeptides have a great impact on the immunomodulatory properties of these molecules. For the engineering of liposome/lipopeptide-based vaccines, the maleimide derivative of Pam(2)CAG appears to be the best candidate.  相似文献   
84.
Photobiological research in the last 30 yr has shown the existence of ultraweak photon emission in biological tissue, which can be detected with sophisticated photomultiplier systems. Although the emission of this ultraweak radiation, often termed biophotons, is extremely low in mammalian cells, it can be efficiently increased by ultraviolet light. Most recently it was shown that UV-A (330 to 380 nm) releases such very weak cell radiation in differentiated human skin fibroblasts. Based on these findings, a new and powerful tool in the form of UV-A-laser-induced biophotonic emission of cultured cells was developed with the intention to detect biophysical changes between carcinogenic and normal cells. With suspension densities ranging from 1 to 8 x 10(6) cells/mL, it was evident that an increase of the UV-A-laser-light induced photon emission intensity could be observed in normal as well as melanoma cells. Using this new detection procedure of ultraweak light emission, photons in cell suspensions as low as 100 microL could be determined, which is a factor of 100 lower compared to previous procedures. Moreover, the detection procedure has been further refined by turning off the photomultiplier system electronically during irradiation leading to the first measurements of induced light emission in the cells after less than 10 micros instead of 150 ms, as reported in previous procedures. This improvement leads to measurements of light bursts up 10(7) photons/s instead of several hundred as found with classical designs. Overall, we find decreasing induction ratings between normal and melanoma cells as well as cancer-prone and melanoma cells. Therefore, it turns out that this highly sensitive and noninvasive device enables us to detect high levels of ultraweak photon emission following UV-A-laser-induced light stimulation within the cells, which enables future development of new biophysical strategies in cell research.  相似文献   
85.
Abstract

The stethoscope is a major symbol of modern medicine. It is used for diagnosis of different conditions and enables physicians to listen to internal body sounds. Electrocardiography was only introduced in medicine in the beginning of the twentieth century. Today measuring heart’s electrical activity is also fundamental cardiac diseases diagnosis. Although performed with independent devices, requiring physician and patient presence in the same physical space, in combination they enhance cardiovascular assessment. In this paper, a digital stethoscope encapsulation was designed, adding new functionality to this advanced medical device. Today wired and wireless communications enable different medical devices to share data and information, over long distances. Using low-cost hardware technologies, the encapsulation will add the ability to acquire and transmit via Bluetooth the Electrocardiographic activity, determined in the same cardiac focus and synchronised with the Phonocardiographic sound recordings. Several encapsulation concepts were developed and prototyped using 3D printing. They were easily fitted to the digital stethoscope and tested in a hospital environment for ergonomics, acoustic and electric signals acquisition. The best concept was chosen with the help of a physician’s opinion and the final prototype performance was very satisfactory.  相似文献   
86.
In previous studies we demonstrated the presence of polysialic acid in Wilms tumor by immunohistochemistry and immunoblotting. We now show by immunoelectron microscopy that the cell surface coat of Wilms tumor cells consists of a layer of amorphous material containing polysialic acid but not detectable amounts of laminin, laminin-nidogen complex, or low density proteoglycan. Therefore, Wilms tumor cells are covered by a highly developed and chemically specialized cell surface coat that does not represent a basement membrane, although it bears some structural similarities. Polysialic acid is present on neural cell adhesion molecule that exists in Wilms tumor as two isoforms of approximately 120 and 140 kDa. The cell surface coat exhibits variation in its thickness along the plasma membrane of a single tumor cell, and the variation is inversely related to the extent of cell-cell contact. It is therefore proposed that polysialic acid may modulate the behavior and invasive potential of Wilms tumor cells.  相似文献   
87.
Spatial and temporal frequency-dependent conductivities are used to interpret four-electrode conductivity measurements on skeletal muscle. The model qualitatively explains the observed dependence of the experimental data on the temporal frequency of the injected current, the angle between the electrode array and the fibre direction and the distance between the electrodes.  相似文献   
88.
BACKGROUND: Inflammation has been shown to play an important role in promoting the response to arterial injury and proinflammatory cytokines, such as tumor necrosis factor (TNF) alpha, are candidate mediators. AG-556 is a tyrosine kinase inhibitor proven to be effective in a model of multiple sclerosis-like syndrome in mice due to its immunomodulating effect. In the current study, we investigated the effect of the tyrphostin AG-556 on neointimal thickening and cytokine profile in a model of arterial injury in the mouse. METHODS: Injury was induced by external cuff placement on the left femoral artery of wild-type C57BL/6 mice. AG-556 dissolved in DMSO was injected intraperitoneally daily to the injured mice in a dosage of 2 mg/mouse. Control mice received DMSO injections. Histological analysis was carried out to assess neointimal formation. Splenocytes were cultured in the absence and presence of a mitogen for evaluation of thymidine incorporation and cytokine production. RESULTS: AG-556 treatment significantly attenuated intimal thickening (43,000+/-17,000 microm2; n=11) when compared to DMSO administration (286,000+/-127,000 microm2; n=10; P<0.05). Basal interferon-gamma production by splenocytes from AG-556-treated mice was increased by approximately 20-fold in comparison with levels in DMSO-treated animals, whereas Con-A induced secretion of the cytokine was similar between both groups. Levels of TNF-alpha, IL-4 and IL-10 in the culture supernatant from treated and non-treated animals did not differ significantly. CONCLUSION: The tyrosine kinase inhibitor AG-556 may have a role in the reduction of intimal thickening. The effect could be mediated via an immune modulating effect involving a significant increase in the smooth muscle cell inhibitory cytokine IFN-gamma.  相似文献   
89.
Endometriosis with perineural involvement   总被引:1,自引:0,他引:1  
  相似文献   
90.

Background  

Cytokine production is critical in ischemia/reperfusion (IR) injury. Acetylcholine binds to macrophages and inhibits cytokine synthesis, through the cholinergic anti-inflammatory pathway. This study examined the role of the cholinergic pathway in cytokine production and hepatic IR- injury.  相似文献   
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