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51.
Dr. Susanne Holmgren Jörgen Jensen Ann-Cathrine Jönsson Kersti Lundin Stefan Nilsson 《Cell and tissue research》1985,241(3):565-580
Summary The presence and distribution of regulatory peptides in nerves and endocrine cells of the stomach, intestine and rectum of a urodele amphibian, the mudpuppy, Necturus maculosus, was studied immunohistochemically in sections or whole-mount preparations of the gut wall. The effect of the occurring peptides on gut motility was studied in isolated strip preparations of circular and longitudinal smooth muscle from different parts of the gut.Bombesin-, neurotensin-, substance P- and VIP-like immunoreactivity was present in abundant nerve fibres in the myenteric plexus of both stomach, intestine and rectum. Single fibres or bundles were present in the circular muscle layer and in a well-developed deep muscular plexus in the intestine and rectum. Immunoreactive nerve cells were found in the myenteric plexus of the stomach, intestine (neurotensin only) and rectum. Gastrin/CCK-like immunoreactivity was observed only in a few fibres in stomach and rectum.Endocrine cells containing bombesin-, met-enkephalin-, gastrin/CCK-, neurotensin-, somatostatin- or substance P- like immunoreactivity were present in the mucosa.The effect of bombesin was an inhibition of the rhythmic activity in circular muscle preparations and in longitudinal muscle from the rectum, while longitudinal muscle from the stomach usually responded with a weak increase in tonus. Neurotensin, like bombesin, was inhibitory on the spontaneous rhythmic activity of circular muscle throughout the gut, while the effect on longitudinal muscle was an increase in tonus. Met-enkephalin and substance P increased the tonus of all types of preparations, and often, in addition, initiated a rhythmic activity superimposed on this maintained tonus. VIP had a general inhibitory effect on the preparations, decreasing tonus and/or abolishing rhythmic activity.It is concluded that bombesin-, neurotensin-, substance P- and VIP-like peptides are present in nerves throughout the urodele gut and may have physiological functions in regulating the motility of the gut. The gastrin/CCK-like peptide present in nerves of the stomach and rectum may affect the function of these parts of the gut. The regulatory peptides present in endocrine cells may, perhaps with the exception of the somatostatin-like peptide, affect the motility humorally. 相似文献
52.
Cooper David N. Smith Barbara A. Cooke Howard J. Niemann Susanne Schmidtke Jörg 《Human genetics》1985,71(3):201-205
Summary Patients with recessive X-linked ichthyosis
Patients with recessive X-linked ichthyosis (RXLI), one hereditary form of scaly skin, lack activity of the enzyme steroid
sulfatase in all tissues studied. To investigate the molecular defect underlying the lack of enzyme activity, we prepared
antisera against normal enzyme by injecting normal placental microsomal suspensions or partially purified steroid sulfatase
into rabbits. Antibody activity was assessed by immunoprecipitation of detergent solubilized steroid sulfatase. In addition,
we prepared rabbit antisera against RXLI placental microsomal suspensions. To detect immunologically cross-reactive material
in patients' placentas, extracts were studied by immunoblot techniques and by competition with normal enzyme for antibody
binding. Patients' extracts did not contain immunoreactive material co-migrating on electrophoresis with purified enzyme nor
did they inhibit immunoprecipitation of normal enzyme. Sera from rabbits immunized with RXLI placental microsomes contain
no antibodies to normal steroid sulfatase, as judged by their failure to immunoprecipitate normal enzyme or to react with
normal steroid sulfatase on immunoblot. Thus the mutation in RXLI appears to reduce steroid sulfatase enzyme protein as well
as enzyme activity.
Portions of this material have appeared in abstract form in Clinical Research 31:564A, 1983 and 32:138A, 1984 相似文献
53.
Primary structure of the glycan chains of normal C 1 esterase inhibitor (C 1-INH) after NMR analysis at 400 MHz 总被引:1,自引:0,他引:1
G Strecker M P Ollier-Hartmann H van Halbeek J F Vliegenthart J Montreuil L Hartmann 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1985,301(11):571-576
The primary structural analysis of O- and N-linked carbohydrate chains of the C-1-esterase inhibitor purified from normal serum was carried out by 400-MHz 1H-NMR spectroscopy. C-1-esterase inhibitor protein of a molecular weight of 116,000 daltons contains 24 O-glycans: NeuAc (alpha 2-3) Gal (beta 1-3) GalNAc, 4 N-glycans: NeuAc (alpha 2-6) Gal (beta 1-4) (GlcNAc (beta 1-2) Man (alpha 1-3) [NeuAc (alpha 2-6) Gal (beta 1-4) GlcNAc (beta 1-2) Man (alpha 1-6)] Man (beta 1-4) GlcNAc (beta 1-4) GlcNAc and 2 N-glycans: NeuAc (alpha 2-3) Gal (beta 1-4) GlcNAc (beta 1-2) Man (alpha 1-3) [NeuAc (alpha 2-3) Gal (beta 1-4) GlcNAc (beta 1-2) Man (alpha 1-6)] Man (beta 1-4) GlcNAc (beta 1-4) GlcNAc. 30% of the N-glycans are fucosylated. 相似文献
54.
Thermal stability of the Z-conformation of the tetranucleoside triphosphate (m5dC-dG)2 总被引:2,自引:0,他引:2
D Genest B Hartmann N T Thuong M Ptak M Leng 《Biochemical and biophysical research communications》1984,125(2):803-811
The tetranucleoside triphosphate d(m5C-G)2 has been studied in solution by circular dichroism and 31P nuclear magnetic resonance as a function of temperature, in presence of 3 M NaClO4. It is shown that in such high ionic strength d(m5C-G)2 may adopt a Z-like conformation for temperatures lower than 5 degrees C. At these temperatures, another conformation, in slow equilibrium with the Z-like one, is also detected. Increasing the temperature leads to a transition from the Z-like conformation to intermediate forms before melting. It is demonstrated that these intermediates are not the B form. 相似文献
55.
A study of the thermal stability of the Z form of (m5dC-dG)3 by resonance Raman spectroscopy. 总被引:1,自引:1,他引:0 下载免费PDF全文
A Laigle L Chinsky P Y Turpin B Hartmann N T Thuong M Leng 《Nucleic acids research》1986,14(8):3425-3434
The thermal stability of the hexanucleoside pentaphosphate m5dCpdGpm5dCpdGpm5 dCpdG has been studied by resonance Raman spectroscopy with 257 nm excitation wavelength. At low temperature and in 3M NaClO4, the Raman spectrum resembles that of poly(dG-dC).poly(dG-dC) in the Z conformation. As the temperature is increased, the position and the intensity of several bands (1312 cm-1, 1482 cm-1, 1584 cm-1 and 1632 cm-1) are modified. The variation of intensity versus temperature is biphasic. Analysis of the results suggests that the increase of temperature induces first a transition from the Z form to an intermediate stable form which then melts. These results and those previously obtained by circular dichroism and 31P nuclear magnetic resonance suggest that the intermediate form belongs to the left family but with changes in the stacking of the bases and the geometry of the phosphate groups as compared to the canonical Z form. 相似文献
56.
In cell suspensions of Pseudomonas carboxydovorans pulsed with lithotrophic substrates (CO or H2) in the presence of oxygen, formation of reduced pyridine nucleotides and of ATP could be demonstrated using the bioluminescent assay. Experiments employing base-acid transition, an uncoupler and inhibitors of ATPase or electron transport enabled us to propose a model for the formation of NAD(P)H in chemolithotrophically growing P. carboxydovorans.The protonophor FCCP (carbonly-p-trifluormethoxyphenylhydrazon) inhibited both, formation of NAD(P)H and of ATP. In the absence of oxygen, a chemical potential imposed by base-acid transition resulted in the formation of NAD(P)H and ATP when electrogenic substrates (CO or H2) were present. This suggests proton motive force-driven NAD(P)H formation. The proton motive force was generated by oxidation of substrate, and not by ATP hydrolysis, as obvious from NAD(P)H formation during inhibition of ATP synthesis by oligomycin and N,N-dicyclohexylcarbodiimide.That the CO-born electrons are transferred via the ubiquinone 10-cytochrome b region to NADH dehydrogenase functioning in the reverse direction, was indicated by inhibition of NAD(P)H formation by HQNO (2-n-heptyl-4-hydroxyquinoline-N-oxide) and rotenone, and by resistance to antimycin A.We conclude that in P. carboxydovorans, growing with CO or H2, electrons and a proton motive force, generated by respiration, are required to drive an reverse electron transfer for the formation of reduced pyridine nucleotides.Abbreviations CODH
carbon monoxide dehydrogenase
- DCCD
N,N-dicyclohexylcarbodiimide
- FCCP
carbonyl-p-trifluormethoxyphenylhydrazon
- HQNO
2-n-heptyl-4-hydroxyquinoline-N-oxide
- pmf
proton motive force 相似文献
57.
58.
The myenteric plexus of the rainbow trout Salmo gairdneri is enclosed within an incomplete Schwann-like sheath which allows bundles of unmyelinated axons to pass into the adjacent smooth muscle layers. Neuronal and non-neuronal constituents of the myenteric plexus are divided into smaller units by endoneurial collagen which in places condenses to form a perineurial covering. The myenteric plexus is avascular but arterioles and fenestrated capillaries are present close to the plexus in the intermuscular space. Small groups of neurones constitute the ganglia of the plexus but as yet few ultrastructural indications of differing neurone types have been observed. Within the neuropil of the ganglia five types of axon profile, characterised by their vesicle content, have been identified. One of these types was only recognisable following the administration of 5-hydroxydopamine. Axo-somatic and axo-dendritic synaptic contacts were only made by Type 1 axons but these were uncommon. The presence of an adrenergic component of the myenteric plexus was confirmed ultrastructually following 6-hydroxydopamine-induced degeneration and also by Falck-Hillarp fluorescence histochemistry which revealed an extensive distribution of adrenergic nerves in the plexus. The structural organisation of the plexus, the comparatively few ultrastructurally recognisable axon and neurone types and the sparsity of synaptic contacts all indicate that the teleost myenteric plexus is less complex than its mammalian counterpart. 相似文献
59.
John Geigert Saul L. Neidleman Demetrios J. Dalietos Susanne K. DeWitt 《Applied microbiology》1983,45(5):1575-1581
The enzymatic synthesis of vicinal, dihalogenated products from alkenes and alkynes is described. The enzymatic reaction required an alkene or alkyne, dilute hydrogen peroxide, a haloperoxidase, and molar amounts of halide ions. Vicinal dichloro, dibromo, and diiodo products could be formed. A hydroxyl group on the carbon adjacent to the carbon-carbon double or triple bond lowered the halide ion concentration needed to produce the dihalo product. This reaction offers one explanation for the origin of natural, vicinal, dihalogenated products, such as those found frequently in marine microogranisms. 相似文献
60.
Alkylsulfonic acids and some S-containing detergents as sulfur sources for growth of Chlorella fusca
Chlorella fusca can utilize the following substances as sole sulfur sources for growth: C1 to C8 n-alkane-1-sulfonates, linear alkylbenzenes sulfonates (LAS), -sulfonated fatty acid esters, polyethylene glycol sulfate and alkylsulfates. Good sulfur sources are alkylsulfonic acids, which are comparable to sulfate. Ethanesulfonic acid was used for comparison of the growth on sulfate and on a sulfonic acid, because best growth was achieved on this C2-sulfonic acid.Growth data of Chlorella on the enviromental important detergents linear alkylbenzene sulfonic acids, -sulfonated fatty acid methylester, Texapon and Sulfopon are presented. So far only microorganisms have been discussed as a source for degradation of sulfonic acids and detergents. It is suggested that green algae could be of similar importance for the biodegradation of these compounds.Abbreviations LAS
Linear alkylbenzene sulfonate
- ES
-sulfonated fatty acid methylester
- DTE
dithiocrythritol 相似文献