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Biomedical subjects

B Berger

Publications and source records attributed to B Berger.

At least 19 recordsLinked to original sources

Placental mosaicism in a case of 46,XY,-22,+t(22;22)(p11;q11) or i(22q) diagnosed at amniocentesis.

46,XY,-22,+t(22;22)(p11;q11) or i(22q) was diagnosed in 15/15 cells from two cultures from the amniotic fluid culture of a 31-year-old patient whose fetus demonstrated cystic hygroma on ultrasound. Cytogenetic studies performed on fetal skin from the abortus revealed the same karyotype as that seen on amniocentesis, but the placenta demonstrated a 46,XY/46,XY,-22,+t(22;22) or i(22q) mosaicism, with 65 per cent of the cells being 46,XY. This case provides an example of placental mosaicism for a normal male karyotype, while the fetus demonstrated non-mosaic trisomy 22.

Adult

Shedding of a rhinovirus minor group binding protein: evidence for a Ca(2+)-dependent process.

Soluble rhinovirus minor group binding activity was found to be shed into the medium upon incubation of HeLa cells at 37 degrees C. Although substantial amounts of this protein were released, no decrease of virus binding to the cell surface was seen. When the membrane-associated receptor was stripped from the cells with trypsin, virus binding was rapidly restored from an intracellular pool even in the absence of de novo protein synthesis. The release of this 85K virus-binding activity was inhibited by metal chelators such as EDTA, EGTA or 1,10-phenanthroline. The potential involvement of a Ca(2+)-dependent protease and/or a phospholipase in this process is discussed.

Calcium

Superior orbicularis oris muscle activity in children with and without cleft lip and palate.

An analysis of integrated electromyographic (IEMG) activity of the superior orbicularis oris muscle was undertaken in 15 children with cleft lip and palate who have undergone surgery compared to 10 children without clefts (control group). Bipolar surface electrodes were used for IEMG recordings of resting level activity and during the swallowing of saliva. Similar resting level activity was observed in both groups. During the swallowing of saliva, activity in children with cleft lip and palate was higher than in children without clefts (noncleft children). Moreover, in the cleft lip and palate group, children with abnormal lip seal showed the highest values for IEMG activity during the swallowing of saliva. This fact suggests that with each swallow of saliva, a greater counteracting effect of the superior orbicularis oris muscle could be produced on the growing maxilla. This may result in a significant long-term effect on the growth of the stomatognathic system, since the process of swallowing is a 24-hour function repeated between 600 and 2400 times each day.

Child

Early evidence of catecholaminergic cell groups in 5- and 6-week-old human embryos using tyrosine hydroxylase and dopamine-beta-hydroxylase immunocytochemistry.

Catecholaminergic systems were visualized in the CNS of human embryos from stage 15-16 (5 gestational week, g.w.) to 18 (6 g.w.) using tyrosine hydroxylase (TH) and dopamine-beta-hydroxylase (DBH) as immunocytochemical markers. At 5 g.w., several TH-like immunoreactive (TH-IR) cell groups were identified in the medulla oblongata, pons, mesencephalon and the anlage of the hypothalamic area. DBH immunoreactivity was restricted to the locus coeruleus and to rare neurons in the medulla oblongata. At 6 g.w., the density of TH-IR neurons was strikingly increased in these different areas--especially in the prospective substantia nigra and ventral tegmental area--and two main bundles of catecholaminergic axons extended from the medulla oblongata until the basal forebrain and from the mesencephalic tegmentum to the anlage of the striatum. These pathways were mainly TH-IR but DBH-IR was also observed in the former. No TH-IR fibers reached the telencephalon at 6 g.w.

Brain

Further indication that distinct dopaminergic subsets project to the rat cerebral cortex: lack of colocalization with neurotensin in the superficial dopaminergic fields of the anterior cingulate, motor, retrosplenial and visual cortices.

The extent of neurotensin (NT) colocalization in the different dopamine (DA) terminal fields of the rat cerebral cortex has been investigated and compared to previous data obtained in man (Gaspar et al., J. Comp. Neurol., 279 (1989) 249-271). Both innervations were revealed with single- or double-labeling immunocytochemical methods. Tyrosine hydroxylase (TH) was used as a specific marker of DA fibers after lesioning the noradrenergic system either with 6-hydroxydopamine (6-OHDA) at birth or DSP4 in adulthood. Three classes of afferents were observed which had a different regional and laminar distribution. First, a dense meshwork of finely dotted NT-positive varicosities occupied restricted areas of the limbic system: the granular retrosplenial and the deep entorhinal cortices and the subicular complex. These NT projections contained no double-labeled fibers and did not correspond to a mixed NT/TH pathway. Secondly, the mixed NT/DA projections identified previously in the prefrontal cortex (Studler et al., Neuropeptides, 11 (1988) 95-100), extended in fact rostrocaudally in layer VI of the whole cerebral cortex and formed small cluster-like groupings in layers II-III of the medial and lateral entorhinal cortex. In all these areas, the mixed NT/TH projections constituted approximately half of the DA terminals. Finally, the DA projections to the superficial layers of the anterior cingulate, motor, retrosplenial and visual cortices, were not colocalized with NT. The DA innervation of layers I-III of the rat anterior cingulate cortex displays striking similarities with that observed in the cingulate, primary motor, premotor and supplementary motor cortices in man: highest regional and laminar density of DA afferents and lack of colocalization with NT. It might thus represent a valuable model for understanding the pharmacology of the DA system besides the mixed DA/NT pathway which does not seem to have a counterpart in the human cerebral cortex. By contrast, that part of the NT innervation of the limbic system which is not colocalized with DA in rat, appears to represent the major fraction of the cortical NT innervation in man.

Animals

Alterations of dopaminergic and noradrenergic innervations in motor cortex in Parkinson's disease.

The motor areas of the cerebral cortex contain dense dopaminergic and noradrenergic innervation in humans. We looked for changes of these innervations in cases with Parkinson's disease (PD). The density of fibers immunolabeled with tyrosine hydroxylase or dopamine-beta-hydroxylase was evaluated in the primary motor, premotor, and prefrontal cortical regions in 6 cases with PD and 7 control cases. Reductions of both noradrenergic and dopaminergic cortical innervations were observed, with similar magnitudes of reduction found in the motor and prefrontal regions of the cortex. Depletion of noradrenergic innervation was diffuse, involving all cortical laminae. Depletion of dopaminergic innervation was laminar specific, with the most significant reductions in layers I and II; reductions in layers V and VI were either less marked (prefrontal cortex) or not detectable (primary motor). The results suggest the existence of two separate mesocortical dopaminergic systems in humans, with the one distributing to upper cortical layers being preferentially involved in PD.

Aged

Brefeldin A induces endoplasmic reticulum-associated O-glycosylation of galactosyltransferase.

Recent data from several laboratories show that Brefeldin A (BFA) induces a microtubule-dependent back-flow of Golgi components to the endoplasmic reticulum (ER) thereby causing disassembly of the Golgi apparatus and its fusion with ER membranes. In order to delineate the effect of BFA on resident Golgi proteins, we investigated its effect on biosynthesis, maturation and intracellular transport of galactosyltransferase (gal-T), an established trans-Golgi enzyme. Using a protocol of metabolic labeling/immunoprecipitation followed by electrophoretic/fluorographic analysis, we show that in the presence of BFA, gal-T matures to a molecular form of 48.5 kD, a size intermediate between the 2 precursor forms of 44 and 47 and the mature form of 54 kD (Strous and Berger: J. Biol. Chem., 257:7623-28, 1982). Little mature form was detectable in the presence of BFA even after prolonged chase times of up to 28 hr. The intermediate form was sensitive to O-glycanase and endoglycosidase H, indicating early O-glycosylation without sialylation and lack of complex N-glycosylation, respectively. In order to define the compartment responsible for O-glycosylation in the presence of BFA, a temperature block of 25 degrees C was applied which inhibited recovery of Golgi elements from BFA-induced fusion with ER. At this temperature and in absence of BFA, biosynthesis of gal-T was not appreciably affected, while maturation was completely inhibited as indicated by the presence of unmodified precursor forms of gal-T. After 60 min preincubation with BFA, a time period sufficient to demonstrate complete fusion of Golgi with ER, subsequent biosynthesis of gal-T at 25 degrees C in absence of BFA led to the intermediate form, while precursor forms were not detectable. These data provide direct evidence for BFA-induced redistribution to the EF of Golgi enzymes involved in O-glycosylation and their early functional involvement in biosynthesis of newly synthesized gal-T.

Acetylglucosaminidase

Dopaminergic innervation of the cerebral cortex: unexpected differences between rodents and primates.

Until recently, views on the organization and role of the mesotelencephalic dopaminergic (DA) systems were mostly based on studies of rodents, and it was assumed that homology existed across mammalian species. However, recent studies of both human and non-human primates indicate that this might not be so. The mesocortical DA system in primates, which is directly involved in the pathophysiology of severe illnesses such as Parkinson's disease and psychoses, shows substantial differences from that of rodents. These differences include much larger, re-organized terminal fields, a different phenotype for the co-localization of neuropeptides and a very early prenatal development.

Animals

Brefeldin A induces a microtubule-dependent fusion of galactosyltransferase-containing vesicles with the rough endoplasmic reticulum.

The fungal drug brefeldin A (BFA) has recently been found to induce a redistribution of medial- and cis-Golgi components to the endoplasmic reticulum (ER), raising the possibility of the existence of a retrograde pathway from the Golgi complex to the ER. Here, we demonstrate a BFA-induced reversible rearrangement of the trans-Golgi membrane protein galactosyltransferase (Gal-T) to the ER in HeLa cells. With immunofluorescence microscopy we have shown that BFA first caused a rapid change of Gal-T immunolabelling from a normal Golgi complex pattern to long and slender structures emanating from the cell centre and co-localizing with tubulin. Then immunofluorescence became ER-like. This effect was not dependent on ongoing protein synthesis and was reversed to normal within 120 min after removal of the drug. Restoration of the Golgi complex after removal of brefeldin A was energy-dependent but not mediated by microtubules nor dependent on protein synthesis. BFA-induced backflow of Gal-T was inhibited by nocodazole, a microtubule-disrupting agent. Immunoelectron microscopy showed that BFA treatment resulted in the fusion of Gal-T-containing vesicles with the ER. Furthermore, sucrose gradient centrifugation showed a significant shift in density of mature Gal-T polypeptides upon BFA treatment: about 40% of the enzyme migrated from its original density (1.13 g/ml) to the density of rough ER (1.19 g/ml). Thus, BFA caused microtubule-dependent vesicular backflow from a trans-Golgi component to the ER followed by fusion of the Golgi-derived vesicles with the ER.

Antifungal Agents

Neurotensin innervation of the human cerebral cortex: lack of colocalization with catecholamines.

We have localized neurotensin (NT) with immunocytochemical methods in the normal human cerebral cortex. Extensive areas of the frontal cortex, the hippocampal formation, and selected areas of the parietal, temporal and occipital lobes, were examined using post-mortem brain tissue. The peptidergic innervation was characteristically restricted to the limbic belt and to the dorsally contiguous regions. NT-labeled perikarya were found throughout the subiculum, including its dorsal supra-callosal continuation. NT terminal plexuses were particularly abundant in layers I-VI of the anterior cingulate cortex, in layer I of area 32 and of medical areas 9, 8, 6 and in layers II-III of area 29, of the presubiculum and entorhinal cortex. Elsewhere, NT fibers were scarce being more frequent in layer I. This regional and laminar pattern differed significantly from that of tyrosine hydroxylase (TH), which was used to label catecholaminergic axons, and preferentially the dopaminergic ones. Even in zones where TH and NT innervations were abundant, such as the anterior cingulate cortex or area 32, double-labeling procedures disclosed no colocalized fibers. The lack of NT-TH colocalization in human, contrasts with previous findings in the rodent cortex, where a contingent of the DA cortical afferents contains NT. The DA mesocortical neuronal population, labeled by TH antisera, thus seems to change its chemical phenotype, by losing the expression of an associated peptidergic neurotransmitter; this could be related to the predominant extension in the ascent of the phylogenetic scale of the non-colocalized, type of cortical DA innervation which is also found in rodents. The possible origins of the cortical, non-dopaminergic NT innervation in human are discussed: thalamo-cortical, subiculo-cortical or intrinsic. Such cortical NT innervation could be very important in limbic circuitry as a regulatory peptide in affective processes and could be involved in the physiology of pain and memory.

Adult

DARPP-32, a phosphoprotein enriched in dopaminoceptive neurons bearing dopamine D1 receptors: distribution in the cerebral cortex of the newborn and adult rhesus monkey.

DARPP-32, a dopamine (DA) and cAMP-regulated phosphoprotein, is associated with dopaminoceptive neurons bearing D-1 receptors in the basal ganglia. The present study addressed the distribution of DARPP-32 in the primate cerebral cortex and its putative association with D-1 receptor laden cells in this structure. DARPP-32-like immunoreactive (LIR) neurons were examined in the cerebral cortex of 3-day-old (P3), 6-week-old (P42), and adult rhesus monkeys. In the younger cases, a large number of DARPP-32 positive neurons, with the morphological characteristics of pyramidal cells, were observed throughout the cortex, in layers V-VI, and to a lesser extent in layer II and uppermost layer III. In the parietal, insular, temporal, and occipital cortices, DARPP-32 positive neurons were arranged in a monolayer in layer Va. They were often clustered in small groups with a bundling of their dendrites. In the primary motor cortex, Betz cells were among the labeled population. In the association and somatosensory areas, the basal dendrites of DARPP-32 positive neurons and the prominent tufting of their apical dendrites in layer I contributed to an essential bilaminar pattern resembling the distribution reported for DA afferents and D-1 receptors in these areas. The prominence and widespread distribution of DARPP-32 positive neurons in layer V may be a specialization of primate cortex since such cells are found only in restricted locations in rodents. The literature on the connections of the cerebral cortex suggests that a large number of the DARPP-32 positive neurons in layer VI and perhaps even in layer Va may be corticothalamic neurons. An important developmental observation was the presence of DARPP-32-LIR neurons in the white matter. They were prominent in the neonates but could not be seen in the adult. Their location as well as their type and shape were reminiscent of interstitial neurons. In the adult monkeys, the distribution of DARPP-32-LIR neurons was more circumscribed: they were numerous in the ventral temporal gyrus and in areas related to the limbic system: caudal orbitofrontal cortex, insula, temporal pole, entorhinal, and anterior cingulate cortex. Weak labeling was detected in layer Va of the superior temporal and parietal cortex, in some prefrontal areas (10, 13, and medial 9), and in the premotor and supplementary motor cortex; in adults, unlike neonates, few DARPP-32-LIR neurons were present in the dorsolateral prefrontal cortex, the primary motor or the primary visual or prestriate cortices.(ABSTRACT TRUNCATED AT 400 WORDS)

Aging

Strategies for the chemoenzymatic preparation of optically active 1-alkyn-3-ols.

A series of (R)- and (S)-1-alkyn-3-ols, chiral building units for the synthesis of leukotrienes and pheromones, were prepared via enantioselective hydrolysis of their racemic esters. While the majority of biocatalysts employed (lipases, fermenting or freeze-dried microorganisms) failed in discriminating between enantiomers, lyophilized cells of baker's yeast (Saccharomyces cerevisiae Hansen) gave (S)-1-alkyn-3-ols and their corresponding (R)-esters with greater than 90% e.e.

Alcohols

C5b-8 and C5b-9 modulate the collagen release of human glomerular epithelial cells.

Aside from their lytic function the late complement components C5b-9 stimulate release of prostanoids, interleukin 1 and oxygen radicals from a number of cells. Since C5b-9 has also been connected to the development of sclerosis in animal models of glomerulonephritis, we addressed the question whether C5b-9 would affect the collagen synthesis. We used human glomerular epithelial cells (GEC) obtained as primary outgrowth cultures. The cells were cultivated in the presence of 14C-proline. Collagen synthesis was quantitated by counting the radioactivity associated with collagenase digestible material. Furthermore, collagen was analyzed by SDS-PAGE. GEC in culture produce spontaneously some collagen type IV. Addition of sublytic doses of highly purified C5b-9 increased the collagen synthesis considerably within 12 to 24 hours. In the absence of C9, C5b-8 stimulated collagen synthesis to a similar extent, whereas in the absence of C7 or C8, the collagen synthesis was not enhanced. Furthermore, fluid-phase-formed C5b-9 complexes did not stimulate the collagen synthesis, indicating that assembly of the complex on the target membrane was required. Since C5b-9 deposits are found in sclerotic areas, our data support the hypothesis that C5b-9, by stimulating collagen synthesis as well as release, might contribute to the development of chronic nephritis.

Animals

Subpopulations of somatostatin 28-immunoreactive neurons display different vulnerability in senile dementia of the Alzheimer type.

We tested whether the vulnerability of somatostatin (SST) neurons in senile dementia of the Alzheimer type (SDAT) depended upon their co-localization with neuropeptide Y (NPY). Density estimates of SST28- and NPY-immunoreactive neurons and percentage of double-labeled SST-NPY neurons were obtained in the cortex (areas 9 and 25) and the bed nucleus of stria terminalis (BST), in 6 SDAT and 5 control cases. Counts of senile plaques (SP) and neurofibrillary tangles (NFT) were done on thioflavin S stains. In both cortical areas, a decrease in the density of SST28-IR neurons was found in SDAT cases (-60% in area 25 and -80% in area 9), whereas density of NPY-IR neurons was unchanged. Accordingly, the proportion of single-labeled SST neurons decreased; this decrease was significantly correlated with SP (r = -0.89, P less than 0.001). We conclude that single SST-IR neurons, in cortical layers II-III, and V, are preferentially lost relative to co-localized SST-NPY neurons. In the BST, no significant reduction of SST-IR, NPY-IR neurons nor of the percentage of single labeled SST neurons was found, despite the presence of SP. Thus one subpopulation of SST neurons, defined by associated neurochemical characters (not co-localized with NPY nor with NADPH diaphorase) and by topography (cortical layers III and V) appears to be particularly vulnerable in SDAT. The potential importance of their position in neural circuitry is emphasized.

Aged

Purification of cadmium-binding proteins from related species of terrestrial Helicidae (Gastropoda, Mollusca): a comparative study.

Three species of terrestrial Helicidae (Helix pomatia, Cepaea hortensis and Arianta arbustorum) were fed cadmium-rich diet in the laboratory. The snails accumulated high amounts of the metal in their hepatopancreas. Most cadmium and some zinc were found, after centrifugation, in the soluble fractions from which a cadmium-binding protein was isolated for each species by ion exchange and gel chromatography. The proteins contained different amounts of cadmium, but little or no zinc, and showed high absorption at 254 nm indicating the presence of cadmium-mercaptide bonds. After gel filtration, a molecular weight of 12,000 was found for cadmium-binding proteins from Helix pomatia and Arianta arbustorum, whereas a molecular weight of 10,000 was found for a cadmium-binding protein from Cepaea hortensis. SDS-polyacrylamide gel electrophoresis showed one single band for each protein from Helix pomatia and Arianta arbustorum and suggested a molecular weight of 11,000 for both species. Amino acid analysis revealed, for each protein, high amounts of cysteine (12-20%), glycine (15-19%), and serine (12-14%), and moderately elevated contents of lysine (9-13%) and alanine (4-8%), but no methionine and only traces, if any, of aromatic amino acids. The ratios of cadmium to cysteine wer 1:5, 1:10 and 1:3 in the proteins from Helix pomatia, Cepaea hortensis and Arianta arbustorum, respectively. Some features of the isolated proteins resembled mammalian metallothioneins. Most characteristics, however, differed from true metallothioneins and were similar to cadmium-binding proteins found in some marine molluscs.

Amino Acids

Catecholamine innervation of the human cerebral cortex as revealed by comparative immunohistochemistry of tyrosine hydroxylase and dopamine-beta-hydroxylase.

The organization of the cortical monoamine systems, dopamine (DA), and noradrenaline (NA), which have been studied extensively in the rat and more recently in the monkey, had not yet been investigated directly in the human brain. We report here the first systematic account of the regional and laminar distributions of the catecholamine fibers in the human cerebral cortex, using immunohistochemistry of the catecholamine biosynthetic enzymes, tyrosine hydroxylase (TH), and dopamine-beta-hydroxylase (DBH) in 13 cytoarchitectonic areas (4, 6, 9, 3b, 5, 40, 17, 18, 23, 24, 29, insula, and hippocampus) sampled postmortem. The noradrenergic (NA) innervation, mapped with DBH-immunoreactivity (DBH-IR), displayed a characteristic density gradient in the neocortex (highest in the primary sensorimotor areas, decreasing rostrally and caudally) that contrasted with the more uniform density in the limbic cortices (24, 23, 29, insula, hippocampus). NA axons were present in all cortical layers and were least numerous in layer I. The DBH-IR fibers were only partly TH-immunostained (10-50%, on double-labeled sections), suggesting a heterogeneity of the cortical NA axons. The putative dopaminergic (DA) fibers were identified by comparing alternate or double-immunolabeled (DBH-TH) sections, as the TH-IR fibers which contain no DBH-IR. A DA-like innervation was present in all cortical areas, with major regional differences in density and laminar distribution, which closely paralleled cytoarchitectural buildups: 1) the DA-like innervation was densest in the agranular areas, primary and secondary motor areas, anterior cingulate, and insula; it distributed throughout layers I-VI; 2) density was lower in the granular cortices, areas 9 (prefrontal cortex), 23, 3b, 5, 40, and 18, displaying a bilaminar pattern in layers I and V-VI. In all areas, DA-like fibers were most abundant in the molecular layer, with a predominant distribution in its deepest part. Convoluted and coily fibers represented a unique morphologic aspect of the CA innervation in the human cortex. These findings are in agreement with findings in nonhuman primates and demonstrate major evolutionary changes in the organization of the cortical aminergic input as compared with rodents. The most striking features are the expansion of the DA innervation to the whole cortex and the peak of highest density in the motor areas. The regional differentiation of NA innervation is also accentuated. Slight differences were found in the laminar distributions of the amines in humans and primates. These data seem quite promising and open new research fields in neurologic and psychiatric diseases.

Adult