Substance P, enkephalins, somatostatin, cholecystokinin, oxytocin, and vasopressin in human spinal cord.

in Neurology (1985), 35(6), 881-90

Several neuropeptides were immunohistologically studied in normal human spinal cords. Substance P, methionine-enkephalin, leucine-enkephalin, and cholecystokinin positive fibers were found in all ... [more ▼]

Several neuropeptides were immunohistologically studied in normal human spinal cords. Substance P, methionine-enkephalin, leucine-enkephalin, and cholecystokinin positive fibers were found in all cytoarchitectonic layers, with a specific distribution pattern for each peptide. Somatostatin, oxytocin, and vasopressin immunoreactivities were restricted to particular spinal layers. Perikarya and proximal dendrites were visualized and classified by comparison with previous Golgi analyses. Substance P was contained in "radiate cells" of layer III, methionine-enkephalin in marginal neurons as well as in layer II "stellate cells," and somatostatin in layer II "islet cells." Several results differed from those reported in other species. Chemical neuroanatomy may provide new insights into the neuronal organization of the human spinal cord. [less ▲]

Substances de croissance de nature hormonale pour l'engraissement: actualisation et perspective d'avenir

in Annales de Gembloux (1987), 93

Les substances naturelles dans la lutte contre le paludisme

Scientific conference (2002, October 17)

Substituabilité partielle des facteurs et efficacité-coût. L'exemple du transport urbain et vicinal belge.

in Economie et Prévision (1992)

Le but de l’article est de mesurer les niveaux d’efficacité d’entreprises de transport, urbain et interurbain, de passagers. Le modèle théorique permet de combiner des facteurs simultanément ... [more ▼]

Le but de l’article est de mesurer les niveaux d’efficacité d’entreprises de transport, urbain et interurbain, de passagers. Le modèle théorique permet de combiner des facteurs simultanément complémentaires et substituables. L’importance des liens de complémentarité entre certains facteurs de production apparaît. Les calculs des niveaux d’efficacité font ressortir l’amélioration des firmes concernées au fil du temps. [less ▲]

Substituents on the alpha-carboxyl group of D-glutamic acid in the peptidoglycan of several bacterial cell walls

in Biochemistry (1967), 6(3), 921-929

Substituts des globules rouges: émulsions de fluorocarbures et solutions d'hémoglobine

in Annales Françaises d'Anesthésie et de Réanimation (1999), 18(2), 211-24

OBJECTIVE: To review the current data on perfluorocarbon (PFC) emulsions and haemoglobin (Hb) solutions. DATA SOURCES: For this paper we analysed the literature using Medline search along with major ... [more ▼]

OBJECTIVE: To review the current data on perfluorocarbon (PFC) emulsions and haemoglobin (Hb) solutions. DATA SOURCES: For this paper we analysed the literature using Medline search along with major review articles. DATA SELECTION AND EXTRACTION: The collected articles were reviewed and selected according to their quality and originality. DATA SYNTHESIS: PFCs are synthetic fluorinated hydrocarbons capable of dissolving, at increased FIO2, large amounts of oxygen. They deliver oxygen at tissular level, and are administered as emulsions containing particles of around 0.1 micron, reaching the smallest vessels. They are exhaled unchanged by the lungs within 7 days. The first clinically used PFC was Fluosol-DA 20%. Currently, Oxyfluor 40% and Oxygent 60% are under evaluation. PFCs are not true blood substitutes, but rather a means to support tissue oxygenation during extreme haemodilution. Solutions of free Hb do not require compatibility testing and are fully saturated with oxygen at ambient FIO2. Hb is either human, bovine or recombinant Hb. In order to maintain adequate intravascular half-life and affinity for oxygen, the Hb molecules are modified by internal cross-linking, polymerisation and encapsulation. After promising results using animal models, some of these modified Hb solutions are now undergoing phase III clinical trials. Among these, diaspirin cross-linked haemoglobin (DCLHb) has been tested in cardiac and orthopaedic surgery, as well as in trauma patients. The initial results of these multicentre trials are currently being analysed. [less ▲]

Substrate Marking by an Invasive Ladybeetle: Seasonal Changes in Hydrocarbon Composition and Behavioral Responses

in PLoS ONE (2013), 8(4),

The multicolored Asian ladybeetle, Harmonia axyridis (Pallas), aggregates inside dwellings during the winter to survive the cold. Recent published reports have highlighted that overwintering individuals ... [more ▼]

The multicolored Asian ladybeetle, Harmonia axyridis (Pallas), aggregates inside dwellings during the winter to survive the cold. Recent published reports have highlighted that overwintering individuals use hydrocarbon markings deposited on surfaces by conspecifics to orient toward aggregation sites. In the current study, monthly GC-MS analyses revealed seasonal modifications in the chemical profile of substrate markings deposited by moving individuals. The markings of overwintering ladybeetles contained larger proportions of heptacosadiene, nonacosadiene, hentriacontadienes, and methyl-nonacosanes, along with a lower proportion of heptacosene and nonacosene. This finding suggests the importance of the unsaturated and/or branched hydrocarbons in the H. axyridis aggregation process. Subsequently, we conducted behavioral assays to test whether (1) there is seasonal variation in the behavioral response of H. axyridis individuals toward substrate markings deposited by conspecifics in the same physiological state and (2) the observed behavioral modification is due to a change in ladybeetle sensitivity and/or a change in the chemical composition of the substrate marking. The results indicate that overwintering individuals exhibit a stronger ‘‘following’’ response toward conspecific substrate markings. This behavior is linked to both the physiological state of ladybeetles and the specific chemical profile of the marking biomolecules deposited under overwintering conditions. [less ▲]

Substrate requirements of the Streptomyces albus G DD carboxypeptidase

in Biochemistry (1970), 9(15), 2961-2970

Substrate Specificity Overlap and Interaction between Adrenoleukodystrophy Protein (ALDP/ABCD1) and Adrenoleukodystrophy-related Protein (ALDRP/ABCD2)

in Journal of Biological Chemistry (2011), 286 (10)

X-linked adrenoleukodystrophy (X-ALD) is a neurodegenerative disorder caused by mutations in the ABCD1 gene, which encodes a peroxisomal member of the ATP-binding cassette (ABC) transporter subfamily D ... [more ▼]

X-linked adrenoleukodystrophy (X-ALD) is a neurodegenerative disorder caused by mutations in the ABCD1 gene, which encodes a peroxisomal member of the ATP-binding cassette (ABC) transporter subfamily D called ALDP. ALDP is supposed to function as a homodimer allowing the entry of CoA-esters of very-long chain fatty acids (VLCFA) into the peroxisome, the unique site of their β-oxidation. ALDP deficiency can be corrected by overexpression of ALDRP, its closest homolog. However, the exact nature of the substrates transported by ALDRP and its relationships with ALDP still remain unclear. To gain insight into the function of ALDRP, we used cell models allowing the induction in a dose-dependent manner of a wild type or a mutated non-functional ALDRP-EGFP fusion protein. We explored the consequences of the changes of ALDRP expression levels on the fatty acid content (saturated, monounsaturated, and polyunsaturated fatty acids) in phospholipids as well as on the levels of β-oxidation of 3 suspected substrates: C26:0, C24:0, and C22:6n-3 (DHA). We found an inverse correlation between the fatty acid content of saturated (C26:0, C24:0) and monounsaturated (C26:1, C24:1) VLCFA and the expression level of ALDRP. Interestingly, we obtained a transdominant-negative effect of the inactive ALDRP-EGFP on ALDP function. This effect is due to a physical interaction between ALDRP and ALDP that we evidenced by proximity ligation assays and coimmunoprecipitation. Finally, the β-oxidation assays demonstrate a role of ALDRP in the metabolism of saturated VLCFA (redundant with that of ALDP) but also a specific involvement of ALDRP in the metabolism of DHA. [less ▲]

Substrates and Gate Dielectrics: the Materials Issue for sub-22 nm CMOS Scaling

Conference (2010, April 08)

Performance scaling of CMOS technologies beyond the 22 nm node will depend on the successful introduction of high mobility materials such as germanium and compound semiconductors on silicon substrates ... [more ▼]

Performance scaling of CMOS technologies beyond the 22 nm node will depend on the successful introduction of high mobility materials such as germanium and compound semiconductors on silicon substrates, which is not straightforward due to important materials incompatibilities. These semiconductors moreover necessitate new gate dielectric materials as the well-proven recipes of “hafnium-based oxides” are not working for various reasons. The lack of a stable, high-quality native oxide for both semiconductors forces materials scientists and device engineers to focus more on the interface rather than on the dielectric material it self. A first part of this paper discusses problems related to the hetero-epitaxial growth of Ge and of III/V materials on Si. By applying a low-high temperature regime, smooth layers of Ge on Si can be obtained. Because of the lattice mismatch, these layers will relax by the formation of misfit dislocations at the interface, combined with threading arms that extend to the surface. The thickness of the layer determines the final density of threading defects, even in case of confined selective growth in windows in a dielectric hard mask, unless specific measures are taken. The polar nature of III/V’s brings about additional problems of anti-phase domain nucleation. This can be solved by providing extra steps on the starting surface in combination with a “pre-deposition” of arsenic. The combination of Ge and III/V selective epitaxy on patterned wafers allows growing confined layers with a low defect density and of high quality. Moreover, by using standard shallow trench isolation as mask, a very natural integration of these materials in standard Si manufacturing can be realized. The second part of this paper deals with the growth of dielectric materials and control of the resulting interfaces. In contrast to the case of Si, both Ge and III/V surfaces are heavily prone to problems with pinning of the surface Fermi level (FLP), which prohibits an efficient control of the channel by varying gate voltages. In the case of Ge, the problem can be solved by decoupling the gate dielectric from the Ge surface by means of an ultra-thin, strained Si epi-layer, after which the well-known gate stack approaches with ALD-grown metal oxides from the Si world can be used. An alternative, promising solution is passivation with thermally grown GeO2 followed by ALD high-k, although this process requires much more care than its Si counterpart. Gate dielectrics on III/V, finally, are probably an even bigger challenge. Apart from the Ga2O+GaGdOx passivation on GaAs, no real solutions of the FLP problem are known. We will discuss the use of sulfur (from thermal treatments with H2S or in the liquid phase with (NH4)2S) in combination with ALD or MBD-grown high-k layers on both GaAs and InGaAs. This will be compared to alternative approaches based on an epitaxially grown interfacial passivation layer of Ge in combination with MBD-grown Al2O3. [less ▲]