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DNA and RNA contents in 20 brain regions or nuclei of the rat were determined by a highly sensitive method using high-performance liquid chromatography with electrochemical detection. The high DNA and RNA contents were found in the hypothalamic nuclei, especially the median eminence-arcuate nucleus. These results may be available for the preparation of nucleic acids as the regional control.  相似文献   
3.
A bioassay for thyroid stimulating immunoglobulins (TSI) of patients with Graves' disease was developed by porcine thyroid monolayer cells. Thyroid cells were prepared by dispersion using collagenase and trypsin. Aliquots of the cell suspension (2 X 10(6) cells/1.5 ml/dish) in Ham's F-12 medium (pH 7.2) containing 10% calf serum and 1.5 mM Hepes were seeded and cultured in air at 36 C. On day 6 of culture, cells were incubated with test samples (IgG or bTSH) in 1 ml of serum-free, 0.5 mM IMX-included fresh medium for an additional time, and cAMP in the cells was measured by radioimmunoassay. Intracellular cAMP was increased within 5 minutes after the addition of bTSH and the maximal increase was observed after 30 min. Responses of cAMP were in a dose-related manner up to 10 mU/ml of bTSH. With the addition of IgG from untreated Graves' patients, dose-related increases in cAMP were also observed up to 10 mg/ml IgG and the maximal response was seen at 2 hours incubation. Thyroid stimulating activity in IgG's from normal subjects and patients with Graves' disease was tested with a dose of 10 mg/ml and 2 hours incubation and the activity was expressed as a percent of the control (incubated in the same experiment without IgG). One hundred forty one of 145 untreated patients showed higher activity (228 +/- 51.8%, mean +/- SD; 127-393%, range) than normal subjects (103 +/- 13.3%, mean +/- SD, n = 24; 80-129%, range). Sequential changes in TSI activity in 27 patients after initiating thionamide drugs were studied for 24 months. Initially all 27 patients showed positive TSI and 6 months later 15 remained positive. At 6 months after that, 10 of 23, 4 of 16, and 2 of 6 followed patients showed positive TSI. These results indicate that this bioassay is clinically useful for detecting TSI.  相似文献   
4.
Acute and chronic effects of γ-butyrolactone-γ-carbonyl-histidyl-prolinamide (DN-1417) were investigated on motor activity, dopamine (DA) metabolites and DA receptors in various brain regions of rats. The motor activity, as measured with Automex recorder, was enhanced after a single injection with DN-1417 (20 mg/kg, IP), and the motor stimulating action persisted during 21 daily injections. Acute DN-1417 elevated both homovanillic acid (HVA) and 3,4-dihydroxyphenylacetic acid (DOPAC) levels in 7 brain regions, prefrontal cortex polar, medial and lateral fields, nucleus accumbens, olfactory tubercles, amygdala and striatum. After chronic treatment for 7 days, the acute effect of DN-1417 on DA metabolites disappeared in all regions except for the striatum in which DN-1417 still increased HVA and DOPAC. The response of striatal DA metabolites was also observed after chronic treatment for 21 days. Chronic DN-1417 produced no significant change in 3H-spiperone binding in the prefrontal cortex, nucleus accumbens, olfactory tubercles and striatum, while striatal 3H-DA binding displaced by 30 nM spiperone was enhanced after chronic treatment. These results indicate that DN-1417 interacts with mesocortical, mesolimbic and nigrostriatal DA systems in the different modes of action. The lack of tolerance to motor hyperactivity, however, raises the question as to whether DN-1417-induced hyperactivity may be mediated by the activation of mesolimbic DA neurons. The involvement of nigrostriatal neurons in DN-1417-induced motor hyperactivity is suggested.  相似文献   
5.
We compared the immunostimulatory effects of chemically synthesized α-galactosylceramides (α-GalCers), α-glucosylceramides (α-GluCers), 6″-monoglycosylated α-GalCer and 6″- or 4″-monoglycosylated α-GluCer and made the following observations: (1) the length of the fatty acid side chain in the ceramide portions greatly affects the immunostimulatory effects of α-GalCers and α-GluCers; (2) the configuration of the 4″-hydroxyl group of the inner pyranose moiety plays an important role in the immunostimulatory effects of monoglycosylated α- -pyranosylceramides; (3) the free 4″-hydroxyl group of the inner pyranose of monoglycosylated α- -pyranosylceramides plays a more important role in their immunostimulatory effects than the free 6″-hydroxyl group.  相似文献   
6.
Concentrations of cadaverine, monoacetylcadaverine and monopropionylcadaverine in the blood of schizophrenic and nonschizophrenic subjects were measured. Two groups, one from the U.S.A. the other from Japan, were tested. Monoacetylcadaverine and monopropionylcadaverine were found elevated in the blood of some schizophrenic patients in comparison with those in controls in each group. Their increase could be caused by a reduced monoamine oxidase activity or by an increased acylation in schizophrenic patients.  相似文献   
7.
Eosinophil accumulation is a characteristic feature of the immune response to parasitic worms and allergens. The cell surface carbohydrate-binding receptor Siglec-F is highly expressed on eosinophils and negatively regulates their accumulation during inflammation. Although endogenous ligands for Siglec-F have yet to be biochemically defined, binding studies using glycan arrays have implicated galactose 6-O-sulfate (Gal6S) as a partial recognition determinant for this receptor. Only two sulfotransferases are known to generate Gal6S, namely keratan sulfate galactose 6-O-sulfotransferase (KSGal6ST) and chondroitin 6-O-sulfotransferase 1 (C6ST-1). Here we use mice deficient in both KSGal6ST and C6ST-1 to determine whether these sulfotransferases are required for the generation of endogenous Siglec-F ligands. First, we characterize ligand expression on leukocyte populations and find that ligands are predominantly expressed on cell types also expressing Siglec-F, namely eosinophils, neutrophils, and alveolar macrophages. We also detect Siglec-F ligand activity in bronchoalveolar lavage fluid fractions containing polymeric secreted mucins, including MUC5B. Consistent with these observations, ligands in the lung increase dramatically during infection with the parasitic nematode, Nippostrongylus brasiliensis, which is known to induce eosinophil accumulation and mucus production. Surprisingly, Gal6S is undetectable in sialylated glycans from eosinophils and BAL fluid analyzed by mass spectrometry. Furthermore, none of the ligands we describe are diminished in mice lacking KSGal6ST and C6ST-1, indicating that neither of the known galactose 6-O-sulfotransferases is required for ligand synthesis. These results establish that ligands for Siglec-F are present on several cell types that are relevant during allergic lung inflammation and argue against the widely held view that Gal6S is critical for glycan recognition by this receptor.  相似文献   
8.
An endo β-1,4-xylanase (XynE15) from a culture broth of a deep subseafloor microorganism, Microcella alkaliphila JAM-AC0309, was purified to homogeneity. The molecular mass of XynE15 was approximately 150 kDa as judged by SDS-PAGE. The optimal pH and temperature for hydrolysis of xylan were pH 8 and 65 °C. The enzyme was stable to incubation for 30 min at up to 75 °C, and the half-life at 50 °C was 48 h. XynE15 hydrolyzed arabinoxylan, oat spelt xylan, and birchwood xylan well, but not avicel, carboxymethylcellulose, or arabinan. Xylooligosaccharides were hydrolyzed to mainly xylobiose from higher than xylotetraose. The genome sequencing analysis of strain JAM-AC03039 revealed that XynE15 was composed of 1,319 amino acids with one catalytic domain and three carbohydrate-binding domains belonging to glycoside hydrolase (GH) family 10 and carbohydrate-binding module (CBM) family 4, respectively.  相似文献   
9.
Sleep and Biological Rhythms - Idiopathic hypersomnia (IH) is a rare sleep disorder characterized by excessive daytime sleepiness, great difficulty upon awakening, and prolonged sleep time. In...  相似文献   
10.
Lectin-like function was demonstrated in this study for a novel water-soluble polymer with phenylboronic acid residues (poly (AAPBA-DMAm)), which induced appreciable proliferation of murine spleen lymphocytes with an increased expression of interleukin-2 (IL-2) receptor on their surface. Consequently, boosted proliferation of lymphocytes with cytotoxic action to YAC-1 cells was achieved by concurrent addition of IL-2 with poly(AAPBA-DMAm) in the medium, indicating this boronate-containing polymer to be worked as an effective immuno-adjuvant for the induction of lymphokine-activated killer (LAK) cells. Flow-cytofluorimetry study revealed that poly(AAPBA-DMAm) competitively inhibited the cellular binding of N-acetylneuraminic acid-specific lectin (Limax Flavus Agglutinin) in a concentration-dependent manner, suggesting that phenylboronate moiety in the polymer may recognize N-acetylneur- aminic acid (sialic acid) residues existing on the plasma-membrane surface of lymphocytes to induce their proliferation.  相似文献   
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