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751.
Trine Jensen El M Aliouat Bettina Lundgren Osvald P Settnes Anna Karlsson Claes Dahlgren Eduardo Dei-Cas Niels Obel 《The Journal of eukaryotic microbiology》1998,45(5):544-547
The production of free radicals in human neutrophils was studied in both Pneumocystis carinii derived from cultures of L2 rat lung epithelial-like cells and Pneumocystis carinii purified from human lung. Using the cytochrome C technique, which selectively measured extracellular superoxide generation, hardly any free radical production was observed after stimulation with cultured rat-derived P. carinii. A chemiluminescence technique, which separately measured intra- and extracellular free radical production, was subsequently employed to differentiate the free radical generation. It was established that 1) P. carinii stimulated intra- but not extracellular free radical production in human neutrophils. 2) opsonized cultured rat-derived P. carinii stimulated human neutrophils to a strong intra-cellular response of superoxide production, and 3) opsonized P. carinii. purified from human lung also stimulated human neutrophils to produce intracellular free radicals. 相似文献
752.
Role of group A streptococcal IgG Fc-receptor in induction of anti-IgG by immunization in the rabbit 总被引:1,自引:0,他引:1
Larissa A. Burova Claes Schalén Irina V. Koroleva Maj-Lis Svensson 《FEMS microbiology letters》1989,47(8-9):443-448
Abstract Previous work has demonstrated that streptococcal IgG Fc-receptors (FcR) may trigger production of anti-IgG after immunization of rabbits with group A streptococci. This effect seemed dependent on in vitro binding of IgG, derived from the growth medium, to the vaccine strains. In the experiments presented here, IgG was eluted from streptococcal strains to be used for immunization of rabbits by 1 M KSCN and washing, a treatment which did not affect the capacity of the strains to bind newly added IgG. Using two IgG FcR-positive group A streptococcal strains (M-types 1 and 22) for intravenous immunization, anti-IgG was found in the sera of 26 out of 28 rabbits, examined 8 weeks after immunization. In contrast, anti-IgG was not induced in 16 rabbits receiving either group A, type T27 or group B, type Ia streptococci both of which lack surface FcR activity. Finally, immunization with purified streptococcal IgG FcR (0.35 mg, given subcutaneously combined with Freund's complete adjuvant and two weeks later intraconjunctivally without adjuvant) also induced anti-IgG. In all rabbits, anti-human rather than anti-rabbit IgG was detected. It is proposed that in vivo interaction between the bacterial FcR and rabbit IgG, resulting in conformation changes in IgG, is a prerequisite for the induction of anti-IgG. Thus, streptococcal triggering of anti-IgG, ascribable to IgG Fc-receptor activity and not requiring presence of foreign IgG, has been demonstrated in the rabbit. 相似文献
753.
754.
In reindeer, subjected to stress, marked changes were found in some blood constituents when compared with unstressed animals, i.e. the white blood cell composition, Cortisol and urea values. Mental stress, due to handling appears to be of great importance in reindeer. Elevated urea values in stressed animals may cause a decreased meat quality. 相似文献
755.
Erik Dahl Bengt Falck Claes Von Mecklenburg Harry Myhrberg Evald Rosengren 《Cell and tissue research》1966,71(4):489-498
Summary The localization of biogenic monoamines in ganglionic tissues from Anodonta piscinalis, Helix pomatia, and Buccinum undatum has been studied by means of the histochemical fluorescence method of Falck and Hillarp.In cerebral, visceral, and pedal ganglia (besides nonfluorescent nerve cells) neurons emitting a green or yellow fluorescence were found. No other cell systems exhibiting a specific fluorescence were observed. An abundance of monoaminergic terminals were found in the central parts of these ganglia. Spectrophotofluorimetric determinations showed that there are large quantities of dopamine and 5-hydroxytryptamine in the tissues investigated. The amounts of dopamine and 5-hydroxytryptamine agree well with the distribution of green and yellow fluorescence, respectively, in the ganglia.There are many similarities between the vertebrate and the molluscan monoaminergic neurons. The morphology of the neurons is the same, the intraneuronal distribution of the monoamines is identical, depletion experiments with reserpine and denervation experiments give the same results, and the synaptic arrangement of monoaminergic fibres on non-adrenergic neurons has the same appearance. Apparently, however, dopamine and 5-hydroxytryptamine are the only monoamines acting as neuronal transmitters in the species investigated.The research reported in this document has been sponsored by the Air Force Office of Scientific Research under Grant AF EOAR 64-5 through the European Office of Aerospace Research (OAR), United States Air Force and by the Swedish Natural Science Research Council. 相似文献
756.
Pui‐Chuen Hui Katia Shtyrkova Chengxin Zhou Xiaoniao Chen James Chodosh Claes H. Dohlman Eleftherios I. Paschalis 《Journal of biophotonics》2020,13(7)
Artificial cornea is an effective treatment of corneal blindness. Yet, intraocular pressure (IOP) measurements for glaucoma monitoring remain an urgent unmet need. Here, we present the integration of a fiber‐optic Fabry‐Perot pressure sensor with an FDA‐approved keratoprosthesis for real‐time IOP measurements using a novel strategy based on optical‐path self‐alignment with micromagnets. Additionally, an alternative noncontact sensor‐interrogation approach is demonstrated using a bench‐top optical coherence tomography system. We show stable pressure readings with low baseline drift (<2.8 mm Hg) for >4.5 years in vitro and efficacy in IOP interrogation in vivo using fiber‐optic self‐alignment, with good initial agreement with the actual IOP. Subsequently, IOP drift in vivo was due to retroprosthetic membrane (RPM) formation on the sensor secondary to surgical inflammation (more severe in the current pro‐fibrotic rabbit model). This study paves the way for clinical adaptation of optical pressure sensors with ocular implants, highlighting the importance of controlling RPM in clinical adaptation. 相似文献
757.
Anna E Bartunek Victor A Claes Philippe R Housmans 《Journal of applied physiology》2002,92(6):2491-2500
The effects of halothane, isoflurane, and sevoflurane on elastic stiffness, which reflects the degree of cross-bridge attachment, were studied in intact cardiac muscle. Electrically stimulated (0.25 Hz, 25 degrees C), isometrically twitching right ventricular ferret papillary muscles (n = 15) at optimal length (L(max)) were subjected to sinusoidal length oscillations (40 Hz, 0.25- 0.50% of L(max) peak to peak). The amplitude and phase relationship with the resulting force oscillations was decomposed into elastic and viscous components of total stiffness in real time. Increasing extracellular Ca(2+) concentration in the presence of anesthetics to produce peak force equal to control increased elastic stiffness during relaxation, which suggests a direct effect of halothane and sevoflurane on cross bridges. 相似文献