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1.
Depressive symptoms during pregnancy are common and may have impact on the developing child. Selective serotonin reuptake inhibitors (SSRIs) are the most prescribed antidepressant treatment, but unfortunately, these treatments can also negatively affect the behavioral development and health of a child during pregnancy. In addition, serotonin (5-HT) exerts neurotrophic actions with thus far not fully known effects in the offspring. The neurotrophic growth factor (NGF) is involved in neuronal cell survival and differentiation, and altered placenta levels have been found to increase the risk for pregnancy complications, similar to those found in women treated with SSRIs. We therefore investigated whether the NGF signaling pathway was altered in the placenta from women treated with SSRIs (n = 12) and compared them with placenta from depressed (n = 12) and healthy mothers (n = 12). Results from immunohistochemical stainings revealed that placental NGF protein levels of SSRI-treated women were increased in both trophoblasts and endothelial cells compared with depressed and control women. In addition, downstream of the NGF receptor TrkA, increased levels of the signaling proteins ROCK2 and phosphorylated Raf-1 were found in stromal cells and a tendency towards increased levels of ROCK2 in trophoblasts and endothelial cells in SSRI-treated women when compared to healthy controls. SSRI-treated women also displayed increased levels of phosphorylated ROCK2 in all placental cell types studied in comparison with depressed and control women. Interestingly, in placental endothelial cells from depressed women, NGF levels were significantly lower compared to control women, but ROCK2 levels were increased compared with control and SSRI-treated women. Taken together, these results show that the NGF signaling and downstream pathways in the placenta are affected by SSRI treatment and/or antenatal depression. This might lead to an altered placental function, although the clinical relevance of our findings still needs to be investigated.  相似文献   
2.
Summary This paper presents a study on the structure and function of Kupffer cells (KC) and liver endothelial cells (LEC) isolated by a simple and rapid technique involving 1) perfusion of the liver with collagenase; 2) cell separation by means of density centrifugation in Percoll; and 3) cell culture, taking advantage of the fact that KC and LEC differ in their preferences for growth substrate. The KC, which attach and spread under serum-free conditions on surfaces of glass or plastic during the first 15 min in culture exhibit a typical macrophage-like morphology including membrane ruffling and a heterogenous content of vacuoles. Moreover, these cells express (a) Fc receptors (FcR) for binding and phagocytosis of erythrocytes covered with immune globulin G (E-IgG), and (b) complement receptors (CR) for binding and serum dependent phagocytosis of erythrocytes covered with either human C3b or mouse inactivated C3b (iC3b). The cells also bind fluid phase fluoresceinated C3b. Approximately 30% of the KC express immune response-associated (Ia)-antigens.The LEC attach and spread on fibronectin coated surfaces, but not on glass or plastic surfaces, during the first two hours in culture with or without serum, and are morphologically distinct from KC. Cultured LEC are well spread out with no membrane ruffling and with numerous large vesicles surrounding the regularly shaped nucleus. These cells bind, but do not ingest E-IgG via the FcR, but no binding of fluid phase C3b or particle fixed C3b or iC3b can be observed. Incubation of LEC with fluorescein amine conjugates of ovalbumin or formaldehyde treated serum albumin, but not with fluoresceinated native serum albumin, results in accumulation of fluorescence specifically localized in the large perinuclear vesicles. Neither KC nor any other cell types tested have the ability to accumulate fluorescence upon incubation with these compounds. Iaantigens are not present on the LEC.Cytochemical demonstration of unspecific esterase, acid phosphatase, and peroxidase reveals different patterns and intensities of staining in KC as compared to LEC.Abbreviations Used KC Kupffer cells - LEC Liver endothelial cells - C Complement - C3b Major fragment of C3 activation - iC3b C3b that has been cleaved by factor I (C3b inactivator), present in serum - meC3b C3b produced by treating purified human C3 with methyl amine - trC3b C3b produced by treating purified human C3 with trypsin - CR Complement receptors for C3b and iC3b - IgG Immune globulin G - IgM Immune globulin M - E Erythrocytes - E-IgG E covered with anti-E IgG - E-IgM E covered with anti-E IgM - E-C3b(h) E-IgM reacted with purified human C1, C4, oxidized C2 and C3 (E-IgMC14xyC2C3b) - E-iC3b(m) E-IgM incubated with C5 deficient serum from AKR mice - FcR Receptors for the Fc portion of IgG - FITC Fluorescein isothiocyanate - FITC-meC3b FITC conjugated to meC3b - FITC-trC3b FITC conjugated to trC3b - FA Fluorescein amine - FA-OA Ovalbumin conjugated with FA - FA-SA Serum albumin conjugated with FA - FA-FSA Formaldehyde-treated serum albumin conjugated with FA - Ia Immune response-associated AcE Acid unspecific esterase acting on alpha naphtyl acetate - NASDAE Unspecific esterase acting on naphthol AS-D acetate - NASDCAE Unspecific esterase acting on napthol AS-D chloroacetate  相似文献   
3.
Fine needle aspiration cytology of thymic tumors   总被引:2,自引:0,他引:2  
Cytologic material was reviewed from 23 mediastinal tumors clinically suspected as thymomas. The thymomas had a characteristic biphasic cell pattern in material obtained by fine needle aspiration biopsy that was easy to recognize and possible to differentiate from carcinoid tumors, malignant lymphomas and oat-cell carcinomas.  相似文献   
4.
Zusammenfassung An einer Anzahl vonHesperis Candida undHesperis matronalis-Pflanzen zeigten sich im Botanischen Garten im Frühjahr 1959 Symptome einer Mosaikkrankheit. In den Trichomen der Blätter, in der Epidermis der Blattmittelrippe, in der Oberhaut des Stengels sowie in der Epidermis der Fruchtwand traten oft auffallend große protoplasmatische X-Körper auf. in denen sich Viruseiweißkristalle verschiedener Größe und Form bildeten.Herrn Professor Dr. Adolf Sperlich zum 80. Geburtstag.  相似文献   
5.
Preliminary crystallographic data for transketolase from yeast   总被引:1,自引:0,他引:1  
Crystals of the vitamin B1-dependent enzyme transketolase from baker's yeast have been grown from the apo- and the holoform of the enzyme, using PEG as precipitant. The crystals are orthorhombic, space group P2(1)2(1)2(1) with cell constants a = 76.3 A, b = 114.2 A, and c = 163.5 A. The crystals are stable in the x-ray beam and diffract to at least 2.2 A on a conventional x-ray source. The enzyme is a dimer of identical subunits, and a Vm value of 2.2 A/dalton indicates that the asymmetric unit contains a dimer. Rotation function calculations using native data (10-5 A) revealed a local 2-fold rotation axis with phi = 0 degree and omega = 20 degrees.  相似文献   
6.
Changes in the activities of UDP-galactose:ceramide galactosyltransferase (CGalT, EC 2.4.1.45), UDP-glucose:ceramide glucosyltransferase (CGlcT, EC 2.4.1.80) and 3'-phosphoadenosine-5'-phosphosulfate (PAPS): galactosylceramide 3'-sulfotransferase (EC 2.8.2.11) over the myelinating period between 12 and 25 days were studied in the brains of control and myelin-deficient rats. Although the activity of galactosyltransferase with ceramides containing hydroxy fatty acids quadrupled in normal male littermates between 14 and 20 days, hardly any increase was observed in the mutant and the activity was less than 10% of control above 20 days of age. With normal fatty acid containing ceramides as acceptors, the activity decreased from 83% of the control at 12 days to approximately 30% after 20 days. Sulfotransferase activity also did not show the normal increase during the 3rd week of life and declined from 60% to 22%. Glucosyltransferase and lysosomal hydrolases in brain and ceramide galactosyltransferase in sciatic nerves appeared to be normal. These results suggest close similarities to the jimpy mutant mouse in which myelin deficiency is also inherited as an x-linked recessive trait.  相似文献   
7.
8.
The expressions for the kinetic constants corresponding to the steady state model for hydrolysis of ATP catalyzed by (Na+ + K+)-ATPase proposed recently are analyzed with the object of determining the rate constants. The theoretical background for the necessary procedures is described. The results of this analysis are: (1) A small class (four) of rate constants are determined directly by the previously published values of the kinetic constants. (2) For a somewhat larger class of rate constants upper and lower bounds may be established. For several rate constants the upper and lower bounds differ by less than a factor 1.6 (for the ‘(Na+ + K+)-enzyme’, i.e. the enzyme activity with K+ and millimolar substrate concentration) and 1.2 (for the ‘Na+-enzyme’, i.e. the activity at micromolar substrate concentrations). (3) Experiments on inhibition by K+ of the Na+-enzyme at various Mg2+ concentrations are reported and analyzed. With the additional assumption that the rate constants governing the addition to ATP of Mg2+ is independent of whether or not ATP is bound to an enzyme molecule, a set of consistent values for all the 23 rate constants in the mechanism may be obtained. (4) The values of some rate constants lend further support to the contention discussed in a previous paper that the enzyme hydrolyzes ATP along two kinetically distinct pathways, depending on the presence of K+ and on the concentration of substrate, without the necessity of having more than one active substrate site per enzyme unit at any time. (5) The results show that while the two enzyme forms, the ‘Na+-enzyme’ E1 and the “K+-enzyme” E2K, add substrate with (second order) rate constants of the same order of magnitude (differing only by a factor of four in favor of the former), the rate constants for the reverse processes differ by a factor of 100, being largest for the K+-enzyme. This is the main reason for the large difference in the Michaelis constants for the two forms reported previously. (6) Compatibility of the model with the well-known rapid dephosphorylation of the phosphorylated enzyme in the presence of K+ requires the presence, at non-zero steady state concentration, of an enzyme-potassium-phosphate intermediate, which is acid labile and is therefore not detected as a phosphorylated enzyme using conventional methods.  相似文献   
9.
The purpose of this study was to try to differentiate histochemically between the various enzymes which may catalyze the hydrolysis of ATP in developing rat dental tissues. Freeze cut and freeze dried sections of molar and incisor teeth were incubated in lead capture-based media at pH 5.0, 7.2 or 9.4 with one of the following substrates: beta-glycerophosphate, AMP, ADP, ATP, AMP-PNP and tetrasodium pyrophosphate. To establish the enzymatic nature of the hydrolysis parallel sections were incubated after prior fixation in either formaldehyde or glutaraldehyde. By comparing the enzymatic stainings obtained with the various substrates and at the different pH:s, it was concluded that ATP can be visibly hydrolyzed in rat dental tissues by alkaline phosphatase (stratum intermedium, apical part of maturation ameloblasts, basal part of all ameloblasts, odontoblasts and subodontoblastic layer), specific ATPase (apical and basal parts of secretory ameloblasts) and ATP pyrophosphatase and/or adenylate cyclase (stratum intermedium, odontoblasts). Acid phosphatase, specific ADPase, 5'-nucleotidase, inorganic pyrophosphatase, 3':5'-cyclic-AMP-phosphodiesterase and adenylate kinase on the other hand, seem not to be engaged in the ATP hydrolysis to such a degree as to complicate the interpretation of the histochemical staining. The alkaline phosphatase part of the ATP hydrolysis appeared to be rather insensitive to aldehyde fixation, while the hydrolysis effected by specific ATPase and ATP pyrophosphatase and/or adenylate cyclase was extinguished after fixation with formaldehyde for 4 h or glutaraldehyde for 10 min.  相似文献   
10.
Summary The purpose of this study was to try to differentiate histochemically between the various enzymes which may catalyze the hydrolysis of ATP in developing rat dental tissues. Freeze cut and freeze dried sections of molar and incisor teeth were incubated in lead capture-based media at pH 5.0, 7.2 or 9.4 with one of the following substrates: -glycerophosphate, AMP, ADP, ATP, AMP-PNP and tetrasodium pyrophosphate. To establish the enzymatic nature of the hydrolysis parallel sections were incubated after prior fixation in either formaldehyde or glutaraldehyde.By comparing the enzymatic stainings obtained with the various substrates and at the different pH: s, it was concluded that ATP can be visibly hydrolyzed in rat dental tissues by alkaline phosphatase (stratum intermedium, apical part of maturation ameloblasts, basal part of all ameloblasts, odontoblasts and subodontoblastic layer), specific ATPase (apical and basal parts of secretory ameloblasts) and ATP pyrophosphatase and/or adenylate cyclase (stratum intermedium, odontoblasts). Acid phosphatase, specific ADPase, 5-nucleotidase, inorganic pyrophosphatase, 3:5-cyclic-AMP-phosphodiesterase and adenylate kinase on the other hand, seem not to be engaged in the ATP hydrolysis to such a degree as to complicate the interpretation of the histochemical staining. The alkaline phosphatase part of the ATP hydrolysis appeared to be rather insensitive to aldehyde fixation, while the hydrolysis effected by specific ATPase and ATP pyrophosphatase and/or adenylate cyclase was extinguished after fixation with formaldehyde for 4 h or glutaraldehyde for 10 min.  相似文献   
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