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991.
Karl Hård Albert Mekking Johannis P. Kamerling Georges A. A. Dacremont Johannes F. G. Vliegenthart 《Glycoconjugate journal》1991,8(1):17-28
Five brain-derived and 17 urinary oligomannose-type oligosaccharides were isolated by ion-exchange chromatography on Mono Q or Dowex, followed by HPLC on Lichrosorb-NH2 from a Persian cat suffering from -mannosidosis. The structures ofthe carbohydrate chains were determined by 500- or 600-MHz1H-NMR spectroscopy. Different oligosaccharide patterns were found in brain and urine. 99% of the urinary oligosaccharides possess an (1-6)-linked mannose residue attached to -mannose, whereas only 5% of the brain-derived oligosaccharides contain such a residue. Furthermore, of the urinary carbohydrate chains 71% end with Man1-4GlcNAc1-4GlcNAc and 29% end with Man1-4GlcNAc, whereas the corresponding amounts are 23% and 77%, respectively, for the brain-derived oligosaccharides.Abbreviations MLEV-17
composite pulse devised by M. Levitt
- HOHAHA
homonuclear Hartman-Hahn spectroscopy
- TPPI
time-proportional phase incrementation
- 2D
two dimensional
- GlcNAc
N-acetylglucosamine
- Man
mannose
- Fuc
fucose 相似文献
992.
Paul Salers L'Houcine Ouafik Pierre Giraud Anne Dutour Jean-Yves Maltese Charles Oliver 《Molecular and cellular biochemistry》1991,106(1):15-24
Thyrotropin-R eleasing hormone (TRH)-degrading pyroglutamyl peptidase I(PGP I) and prolyl endopeptidase (PE) activities have been demonstrated in rat insulinoma RINm 5F cell line. These two enzymes catalyze the conversion of TRH to Histydyl-Proline-Diketopiperazine and to acid TRH respectively.After cell fractionation, we found all the PGP I and PE activities in the cytosolic fraction. The membranebound PGP II activity is not detectable in the RINm 5F cells. Further investigations on these two cytosolic enzymes show that pyroglutamyl- and proline-containing peptides are inhibitors of each TRH-degrading enzyme.Gelfiltration chromatography on Sephadex G100 shows that PGP I and PE activity have an apparent molecular mass of about 18 kDa and 57 kDa, respectively. Kinetic analysis with TRH as substrate, gives a Km of 44 µM and 235 µM, and a Vmax of 1.49 and 8.80 pmoUmin/µg protein for PGP I and PE, respectively. Immunoreactive TRH, His-Pro-Diketopiperazine and acid TRH levels in the cell line extracts are 2.2 ± 0.9, 22.5 ± 11.1 and 28.7 ± 14.6pg/106 cells, respectively. When cells have been incubated for 2 to 72 hours with a P. E. inhibitor (Z-Gly-Pro-CHN2) at 5 × 10–7M, both cell PGP I and PE activities are inhibited. No change in the cellular content of immunoreactive TRH, His-Pro-Diketopiperazine and acid TRH have been observed in treated cells.These data suggest that TRH is not degraded by cytosolic, unspecific PGP I and PE enzymes in RINm 5F. The finding that these cells contain 10 and 13 times more His-Pro-Diketopiperazine and acid TRH than TRH may be an indirect evidence for the existence of another precursor than TRH for these two peptides or of the possibility that TRH can be degraded by other peptidases.Abbreviations TRH
Thyrotropin-Releasing Hormone or Thyroliberin
- His-Pro-DKP
Histidyl-ProlineDiketopiperazine
- TRH-OH
acid TRH or deamidated TRH
- LH-RH
Luteinizing Hormone-Releasing Hormone
- Z-Gly-Pro-CHN2
N-benzyloxycarboxyl-Gly-Pro-diazomethylketone
- PGP
Pyroglutamyl Peptidase, PGP I (EC 3.4.19.3) and PGP II (EC 3.4.19.-)
- PE
Prolyl Endopeptidase or post-proline cleaving enzyme (EC 3.4.21.26) 相似文献
993.
Differential cytotoxicity and mycotoxin content among isolates of Fusarium moniliforme 总被引:1,自引:1,他引:0
William P. Norred Charles W. Bacon Ronald D. Plattner Ronald F. Vesonder 《Mycopathologia》1991,116(1):37-43
Curvularia lunata was found causing (disseminated phaeohyphomycosis among a group of Nezara viridula (Insecta:Heteroptera) parasitizing vegetable crop Vigna unguiculata. Dark lesions were seen on pronotum and abdominal sterna. Experimental lesions were produced by applying 0.1 ml of 6.2 × 108cfu/ml–1 on abdominal sterna. Histopathology revealed that almost all internal organs and tissues showed extensive damage. It is interesting to note that C. lunata exhibited predeliction for chitinous tissues and elicited cellular immune response by granulocytes (phagocytosis). This is the first report of phaeohyphomycosis of an insect, extending the disease to invertebrates.A promising research career of one of the authors (Mrs. Vinita Dubey) was cut short by untimely death. This paper is dedicated to her memory. 相似文献
994.
Summary Retinopetal neurons were visualised in the telencephalon and diencephalon of an air-breathing teleost fish, Channa punctata, following administration of cobaltous lysine to the optic nerve. The labelled perikarya (n=45–50) were always located on the side contralateral to the optic nerve that had received the neuronal tracer. The rostral-most back-filled cell bodies were located in the nucleus olfactoretinalis at the junction between the olfactory bulb and the telencephalon. In the area ventralis telencephali, two groups of telencephaloretinopetal neurons were identified near the ventral margin of the telencephalon. The rostral hypothalamus exhibited retrogradely labelled cells in three discrete areas of the lateral preoptic area, which was bordered medially by the nucleus praeopticus periventricularis and nucleus praeopticus, and laterally by the lateral forebrain bundle. In addition to a dorsal and a ventral group, a third population of neurons was located ventral to the lateral forebrain bundle adjacent to the optic tract. The dorsal group of neurons exhibited extensive collaterals; a few extended laterally towards the lateral forebrain bundle, whereas others ran into the dorsocentral area of the area dorsalis telencephali. A few processes extended via the anterior commissure into the telencephalon ipsilateral to the optic nerve that had been exposed to cobaltous lysine. However, the ventral cell group did not possess collaterals. In the diencephalon, retinopetal cells were visualised in the nucleus opticus dorsolateralis located in the pretectal area; these were the largest retinopetal perikarya of the brain. The caudal-most nucleus that possessed labelled somata was the retinothalamic nucleus; it contained the largest number of retinopetal cells. The limited number of widely distributed neurons in the forebrain, some with extensive collaterals, might participate in functional integration of different brain areas involved in feeding, which in this species is influenced largely by taste, not solely by vision. 相似文献
995.
Olle Johansson Marita Hilliges Claes-Göran Östenson Elvi Sandberg Suad Efendic Viktor Mutt 《Cell and tissue research》1991,263(2):395-398
Summary The occurrence of diazepam-binding inhibitor (DBI), isolated and characterized from porcine upper intestine, was examined in the pancreas of Sprague-Dawley albino rats using indirect immunofluorescence. The polypeptide was found in the endocrine Langerhans islets and, utilizing double-labelling controls, it was shown to be present within the peripherally located glucagon-containing cells. Regulation of islet hormone production may therefore be under DBI control. 相似文献
996.
Summary The light-evoked response pattern and morphology of one interplexiform cell were studied in the goldfish retina by intracellular recording and staining. The membrane potential of the cell spontaneously oscillated in the dark. In response to a brief light stimulus, the membrane potential initially gave a slow transient depolarization. During maintained light, the oscillations showed a tendency to be suppressed; the response of the cell to the offset of the stimulus was not so prominent. The perikaryon of the interplexiform cell was positioned at the proximal boundary of the inner nuclear layer. The cell had two broad layers of dendrites; one was diffuse in the inner plexiform layer, the other was more sparse in the outer plexiform layer. The morphological and electrophysiological characteristics of the cell are discussed in relation to dopaminergic interplexiform cells and the light-evoked release pattern of dopamine in the teleost retina. 相似文献
997.
Michel Goldberg Jacqueline Feinberg Sylvie Lecolle Marcia A. Kaetzel Dominique Rainteau James L. Lessard John R. Dedman Serge Weinman 《Cell and tissue research》1991,263(1):81-89
Summary Annexin VI and actin were detected by immunoblot analysis in the enamel- and dentin-related portions of dental tissues. Annexin VI was found mainly in the particulate fraction whereas actin was detected in both the soluble and particulate fractions. By immunoelectron microscopy, annexin VI antibodies conjugated with colloidal gold were seen to label the mitochondria, the cytosol and the nucleus of secretory ameloblasts and odontoblasts of rat incisor. In the processes of these cell, the plasmalemmal undercoat was labeled. Antiactin antibodies labeled the desmosome-like junctions, the cytosol, and the mitochondria of the cell bodies. Extensive labeling was seen at the periphery of the Tomes' processes and odontoblast processes. These results suggest that annexin VI may play a role in Ca2+-regulation in the cell bodies, especially as a calcium receptor protein in the mitochondria. Moreover, annexin VI and actin seem to be co-distributed in secretory processes. Thus, these proteins might be both involved in exocytotic and endocytotic events. 相似文献
998.
N. Aste C. Viglietti-Panzica A. Fasolo C. Andreone H. Vaudry G. Pelletier G. C. Panzica 《Cell and tissue research》1991,265(2):219-230
Summary In the present study, we have demonstrated, by means of the biotin-avidin method, the widespread distribution of neuropeptide Y (NPY)-immunoreactive structures throughout the whole brain of the Japanese quail (Coturnix coturnix japonica). The prosencephalic region contained the highest concentration of both NPY-containing fibres and perikarya. Immunoreactive fibres were observed throughout, particularly within the paraolfactory lobe, the lateral septum, the nucleus taeniae, the preoptic area, the periventricular hypothalamic regions, the tuberal complex, and the ventrolateral thalamus. NPY-immunoreactive cells were represented by: a) small scattered perikarya in the telencephalic portion (i.e. archistriatal, neostriatal and hyperstriatal regions, hippocampus, piriform cortex); b) medium-sized cell bodies located around the nucleus rotundus, ventrolateral, and lateral anterior thalamic nuclei; c) small clustered cells within the periventricular and medial preoptic nuclei. The brainstem showed a less diffuse innervation, although a dense network of immunopositive fibres was observed within the optic tectum, the periaqueductal region, and the Edinger-Westphal, linearis caudalis and raphes nuclei. Two populations of large NPY-containing perikarya were detected: one located in the isthmic region, the other at the boundaries of the pons with the medulla. The wide distribution of NPY-immunoreactive structures within regions that have been demonstrated to play a role in the control of vegetative, endocrine and sensory activities suggests that, in birds, this neuropeptide is involved in the regulation of several aspects of cerebral functions.Abbreviations
AA
archistriatum anterius
-
AC
nucleus accumbens
-
AM
nucleus anterior medialis
-
APP
avian pancreatic polypeptide
-
CNS
centrai nervous system
-
CO
chiasma opticum
-
CP
commissura posterior
-
CPi
cortex piriformis
-
DIC
differential interferential contrast
-
DLAl
nucleus dorsolateralis anterior thalami, pars lateralis
-
DLAm
nucleus dorsolateralis anterior thalami, pars medialis
-
E
ectostriatum
-
EW
nucleus of Edinger-Westphal
-
FLM
fasciculus longitudinalis medialis
-
GCt
substantia grisea centralis
-
GLv
nucleus geniculatus lateralis, pars ventralis
-
HA
hyperstriatum accessorium
-
Hp
hippocampus
-
HPLC
high performance liquid chromatography
-
HV
hyperstriatum ventrale
-
IF
nucleus infundibularis
-
IO
nucleus isthmo-opticus
-
IP
nucleus interpeduncularis
-
IR
immunoreactive
-
LA
nucleus lateralis anterior thalami
-
LC
nucleus linearis caudalis
-
LFS
lamina frontalis superior
-
LH
lamina hyperstriatica
-
LHRH
luteinizing hormone-releasing hormone
-
LoC
locus coeruleus
-
LPO
lobus paraolfactorius
-
ME
eminentia mediana
-
N
neostriatum
-
NC
neostriatum caudale
-
NPY
neuropeptide Y
-
NIII
nervus oculomotorius
-
NV
nervus trigeminus
-
NVI
nervus facialis
-
NVIIIc
nervus octavus, pars cochlearis
-
nIV
nucleus nervi oculomotorii
-
nIX
nucleus nervi glossopharyngei
-
nBOR
nucleus opticus basalis (ectomamilaris)
-
nCPa
nucleus commissurae pallii
-
nST
nucleus striae terminalis
-
OM
tractus occipitomesencephalicus
-
OS
nucleus olivaris superior
-
PA
palaeostriatum augmentatum
-
PBS
phosphate-buffered saline
-
POA
nucleus praeopticus anterior
-
POM
nucleus praeopticus medialis
-
POP
nucleus praeopticus periventricularis
-
PP
pancreatic polypeptide
-
PYY
polypeptide YY
-
PVN
nucleus paraventricularis magnocellularis
-
PVO
organum paraventriculare
-
R
nucleus raphes
-
ROT
nucleus rotundus
-
RP
nucleus reticularis pontis caudalis
-
Rpc
nucleus reticularis parvocellularis
-
RPgc
nucleus reticularis pontis caudalis, pars gigantocellularis
-
RPO
nucleus reticularis pontis oralis
-
SCd
nucleus subcoeruleus dorsalis
-
SCv
nucleus subcoeruleus ventralis
-
SCNm
nucleus suprachiasmaticus, pars medialis
-
SCNl
nucleus suprachiasmaticus, pars lateralis
-
SL
nucleus septalis lateralis
-
SM
nucleus septalis medialis
-
Ta
nucleus tangentialis
-
TeO
tectum opticum
-
Tn
nucleus taeniae
-
TPc
nucleus tegmenti pedunculo-pontinus, pars compacta
-
TSM
tractus septo-mesencephalicus
-
TV
nueleus tegmenti ventralis
-
VeL
nucleus vestibularis lateralis
-
VLT
nucleus ventrolateralis thalami
-
VMN
nucleus ventromedialis hypothalami
A preliminary report of this study was presented at the 15th Conference of European Comparative Endocrinologists, Leuven, Belgium, September 1990 相似文献
999.
Summary A single neuronal cell assay of neurite growth was utilized to determine types and domains of neuronal proteoglycans involved in neurite growth on laminin. Perturbations of biosynthesis and processing, enzymatic digestion with specific lyases, and competition with glycosaminoglycan side chains produced complementary data consistent with a molecular model implicating glycosaminoglycan (GAG) residues of heparan sulphate proteoglycans (HSPGs) in neurite growth. The observations suggest that HSPGs promote neurite growth on laminin by bridging between binding domains for HSPGs on laminin and on the neuronal cell surface, and that the bridge is tethered at both ends by noncovalent interactions between the binding domains and GAG side chains. Sulphation of the GAGs of HSPGs appears to be critical to the tethering and/or neurite growth-promoting activity of neuronal HSPGs. 相似文献
1000.
Uwe Wolfrum 《Cell and tissue research》1991,266(2):231-238
Summary Long ciliary rootlets are a characteristic feature of the dendritic inner segments of the sensory cells in insect sensilla. These rootlets are composed of highly ordered filaments and are regularly cross-striated. Collagenase digestion and immunohistochemistry reveal that the rootlets are probably not composed of collagen fibers. However, double-labeling experiments with phalloidin and anti--actinins show that antibodies to -actinin react with the ciliary rootlets of the sensilla, but do not stain the scolopale, which is composed of actin filaments as visualized by phalloidin. Antibodies to centrin, a contractile protein isolated from flagellar rootlets of green algae, also stain the ciliary rootlets. Within the ciliary rootlets of insect sensilla, -actinin may be associated with filaments other than actin filaments. The immunohistochemical localization of a centrin-like protein suggests that contractions probably occur within the rootlets. The centrin-like protein may play a role during the mechanical transduction or adaptation of the sensilla. 相似文献