Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P50583 (asymmetrical)
 12,197 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Regional cerebral blood flow (rCBF) was determined by single photon emission CT (SPECT) with N-isopropyl-p-[123I]iodoamphetamine in 22 patients with clinically diagnosed senile dementia of Alzheimer type (SDAT) and in 18 age matched controls. We calculated asymmetry indices (AIs) of rCBF for matched right-left regions of interest. rCBF of parietal lobe in SDAT patients was significantly most laterally asymmetrical, but the least in occipital lobe. Lateral asymmetry of rCBF in SDAT patients correlated with asymmetry of language and visuospatial functions; decreased rCBF in the left parietal lobe was associated with language dysfunction, and that in the right parietal lobe, with visuospatial dysfunction. Furthermore cerebellar AIs correlated negatively with those of the cerebral hemisphere and lower frontal region in SDAT patients. The results demonstrate that rCBF measurement by 123I-IMP SPECT is useful to detect lateral asymmetry in reduction of rCBF in SDAT.
Kaku Igaku 1990 Dec
PMID:[Asymmetry of cerebral blood flow in patients with senile dementia of Alzheimer type by SPECT using I-123 IMP]. 229 Feb 11

Open-channel ion permeation properties were investigated for Ca++-activated K+ (CaK) channels in solutions of K+ and its analogues T1+, Rb+, and NH4+. Single CaK channels were inserted into planar lipid bilayers composed of neutral phospholipids, and open-channel current-voltage (I-V) relations were measured in symmetrical and asymmetrical solutions of each of these individual ions. For all concentrations studied, the zero-voltage conductance falls in the sequence K+ greater than T1+ greater than NH4+ greater than Rb+. The shape of the I-V curve in symmetrical solutions of a single permeant ion is non-ohmic and is species-dependent. The I-V shape is sublinear for K+ and T1+ and superlinear for Rb+ and NH4+. As judged by reversal potentials under bi-ionic conditions with K+ on one side of the bilayer and the test cation on the other, the permeability sequence is T1+ greater than K+ greater than Rb+ greater than NH4+ at 300 mM, which differs from the conductance sequence. Symmetrical mixtures of K+ or NH4+ with Rb+ show a striking anomalous mole fraction behavior, i.e., a minimum in single-channel conductance when the composition of a two-ion mixture is varied at constant total ion concentration. This result is incompatible with present models that consider the CaK channel a single-ion pore. In total, the results show that the CaK channel finely discriminates among K+-like ions, exhibiting different energy profiles among these species, and that several such ions can reside simultaneously within the conduction pathway.
Biophys J 1986 Dec
PMID:Multi-ion conduction and selectivity in the high-conductance Ca++-activated K+ channel from skeletal muscle. 243 47

A cell-free system was developed to study the replication of simian rotavirus SA11. The components of the system included (i) subviral particles prepared from infected cells to template the synthesis of viral RNA and (ii) an mRNA-dependent rabbit reticulocyte lysate to support protein synthesis. Based upon nuclease-sensitivity, approximately 20% of the RNA made in vitro was double-stranded (dsRNA) and 80% single-stranded (ssRNA). Electrophoretic analysis of the RNA products on polyacrylamide and low pH agarose gels showed that the system supported the synthesis of 11 dsRNAs and 11 positive-sense ssRNAs that corresponded in size to authentic viral RNAs. The synthesis of dsRNA in vitro was determined to be an asymmetrical process in which a nuclease-sensitive positive-strand RNA acted as a template for the synthesis of negative-strand RNA. The system also supported the initiation of negative-strand RNA using exogenous viral positive-strand RNA as a template. Finally, analysis of subviral particles recovered from reactions suggested that viral proteins made in vitro assembled into nucleoprotein complexes which were similar to those present in infected cells. Together, these results indicate that the cell-free system supported rotavirus RNA replication, transcription and the assembly of subviral particles.
Virus Res 1986 Dec
PMID:Synthesis of simian rotavirus SA11 double-stranded RNA in a cell-free system. 243 20

Asymmetrical transport of macromolecules between plasma and the peritoneal cavity results primarily from unidirectional lymphatic removal from the peritoneal cavity. Recent work suggests, however, that macromolecular transport across the peritoneal-plasma barrier via the capillary wall (i.e., the peritoneal membrane) may also be asymmetrical. We determined the diffusive and convective transport properties for creatinine, p-aminohippurate, and neutral dextran (13-40 A) across the peritoneal membrane in the dialysate to blood direction during peritoneal dialysis using isotonic and hypotonic solutions in awake New Zealand White rabbits. Values of the diffusive permeability-area product that were calculated during the isotonic exchange were similar to, yet somewhat smaller than, those previously determined in the blood to dialysate direction for all test solutes. Solute reflection coefficients that were calculated during the hypotonic exchange were variable, yet the resulting mean solute reflection coefficient values for all the test solutes were similar to those previously determined in the blood to dialysate direction. We conclude that asymmetrical peritoneal transport of macromolecules with radii less than 40 A is not due to asymmetrical transport across the peritoneal membrane.
Am J Physiol 1989 Dec
PMID:Dialysate to blood transport of macromolecules during peritoneal dialysis. 248 3

Fos and Jun proteins form a tight complex which binds specifically to the AP1 recognition sequence, a palindromic DNA element also referred to as the TPA responsive element (TRE). To elucidate the mechanism of Fos-Jun interaction with the TRE we have performed UV cross-linking studies using oligonucleotides where thymines were replaced with bromouracil. Our results indicate that both Fos and Jun directly contact the TRE but that the interaction of Fos and Jun with thymines in structurally equivalent positions in the two half sites of the TRE is different. In addition, we have carried out a comprehensive mutagenesis study of the TRE by introducing all possible point mutations plus thymine----uracil substitutions into the palindromic TRE core sequences and the adjacent nucleotides on both sides. The results of this analysis clearly show that the palindromic TRE is asymmetrical with respect to binding of Fos-Jun. We also show that a Fos protein complex with a homodimeric DNA binding site binds considerably less efficiently to TRE mutants with a perfect dyad symmetry compared with the binding to the wild-type TRE. This demonstrates that the asymmetrical recognition of the TRE is not due to the heterodimeric nature of the Fos/Jun complex but directly related to an asymmetry in the TRE sequence. The methyl groups of all four thymine residues within the TRE seem to be functionally crucial since thymine----uracil substitutions strongly reduce or abolish binding to Fos/Jun. The relevance of structurally equivalent methyl groups in the TRE core sequence is different, lending further support to the conclusion that the TRE is asymmetrical.
EMBO J 1989 Dec 01
PMID:Asymmetrical recognition of the palindromic AP1 binding site (TRE) by Fos protein complexes. 251 Oct 3

The gene encoding diadenosine 5',5'''-P1,P4-tetraphosphate (Ap4A) phosphorylase from yeast was isolated from a lambda gt11 library. The DNA sequence of the coding region was determined, and more than 90% of the deduced amino acid sequence was confirmed by peptide sequencing. The Ap4A phosphorylase gene (APA1) is unique in the yeast genome. Disruption experiments with this gene, first, supported the conclusion that, in vivo, Ap4A phosphorylase catabolizes the Ap4N nucleotides (where N is A, C, G, or U) and second, revealed the occurrence of a second Ap4A phosphorylase activity in yeast cells. Finally, evidence is provided that the APA1 gene product is responsible for most of the ADP sulfurylase activity in yeast extracts.
J Bacteriol 1989 Dec
PMID:Isolation, characterization, and inactivation of the APA1 gene encoding yeast diadenosine 5',5'''-P1,P4-tetraphosphate phosphorylase. 255 64

Two enzymatic activities that split diadenosine triphosphate have been reported in Escherichia coli: a specific Mg-dependent bis(5'-adenosyl) triphosphatase (EC 3.6.1.29) and the bis(5'-adenosyl) tetraphosphatase (EC 3.6.1.41). In addition to the activities of these two enzymes, a different enzyme activity that hydrolyzes dinucleoside polyphosphates is described. After purification and study of its molecular and kinetic properties, we concluded that it corresponded to the 5'-nucleotidase (EC 3.1.3.5) that has been described in E. coli. The enzyme was purified from sonic extracts and osmotic shock fluid. From sonic extracts, two isoforms were isolated by chromatography on ion-exchange Mono Q columns; they had a molecular mass of about 100 kilodaltons (kDa). From the osmotic shock fluid, a unique form of 52 kDa was recovered. Mild heating transformed the 100-kDa isoform to a 52-kDa form, with an increase in activity of about threefold. The existence of a 5'-nucleotidase inhibitor described previously, which associates with the enzyme and is not liberated in the osmotic shock fluid, may have been responsible for these results. The kinetic properties and substrate specificities of both forms (52 and 100 kDa) were almost identical. The enzyme, which is known to hydrolyze AMP and uridine-(5')-diphospho-(1)-alpha-D-glucose, but not adenosine-(5')-diphospho-(1)-alpha-D-glucose, was also able to split adenosine-(5')-diphospho-(5)-beta-D-ribose, ribose-5-phosphate, and dinucleoside polyphosphates [diadenosine 5',5'''-P1,P2-diphosphate,diadenosine 5',5'''-P1,P3-triphosphate, diadenosine 5',5'''-P1,P4-tetraphosphate, and bis(5'-guanosyl) triphosphate]. The effects of divalent cations and pH on the rate of the reaction with different substrates were studied.
J Bacteriol 1989 Dec
PMID:Hydrolysis of bis(5'-nucleosidyl) polyphosphates by Escherichia coli 5'-nucleotidase. 255 71

The distribution and morphology of neurons labelled with antisera to glutamate or aspartate were examined, at the light and electron microscope levels, in the rat visual cortex. Using widely accepted light microscopic features as well as well-established nuclear, cytoplasmic, and synaptic criteria, we noted that glutamate-immunoreactive neurons were pyramidal cells distributed in layers II-VI, with an increased concentration in layers II and III. Aspartate immunoreactivity was localized chiefly to pyramidal neurons in layers II-VI. However, approximately 10% of immunolabeled cells were nonpyramidal neurons scattered throughout the cortex. Cell-body measurements revealed that, for both groups of neurons, layer V contained the largest labelled neurons, whereas layers IV and VI contained the smallest. Furthermore, in every layer, aspartate-stained neurons were larger than glutamate-positive cells. Finally, glutamate- and aspartate-labelled axon terminals formed asymmetrical synapses, which are presumably excitatory in nature, primarily with dendritic spines. These findings, together with recent detailed studies of the projections of glutamate- and aspartate-labelled cortical neurons, may provide essential background information for studies aimed to elucidate the function(s) of excitatory amino acids in the cortex and their role in pathological conditions.
J Comp Neurol 1989 Dec 08
PMID:Excitatory transmitter amino acid-containing neurons in the rat visual cortex: a light and electron microscopic immunocytochemical study. 257 98

The ambulatory status of 74 neonatal intensive care unit survivors with cerebral palsy, excluding those with central nervous system malformations and syndromes, was assessed at eight years of age. Detailed examinations were completed at two and eight years of age; of the 47 who were sitting by two years, 46 became ambulatory, and a total of 47 of the 74 children became ambulatory. The clinical type of cerebral palsy at two years of age related significantly to eight-year ambulation. However, between two and eight years the diagnosis was changed for 18 children. At two years of age the tonic labyrinthine, asymmetrical and symmetrical tonic neck and Moro reflexes related significantly to ambulation; in five of 27 children not walking, these reflexes were absent by two years of age. Foot placement and/or parachute reactions at two years were found in more than one-third of children not walking. Multivariate analysis determined that age at sitting explained 91 per cent of the variance in ambulation. No other variables, combined with sitting, increased this prediction.
Dev Med Child Neurol 1989 Dec
PMID:Early prognosis for ambulation of neonatal intensive care survivors with cerebral palsy. 259 70

We recently described an indirect double sandwich ELISA (Klein-Schneegans et al., J. Immunol. Methods (1989) 119, 117) which permits the specific and quantitative measurement of mouse IgM, IgA and IgG subclasses with one major exception: IgG2a of the b allotype (Igh-1b in mouse strains such as C57BL/6) could not be reliably quantitated even by a very specific and sensitive asymmetrical sandwich ELISA (using two different anti-IgG2a isotype antibodies for capture and for detection). We now describe a similar method based on the use of two different anti-IgG2a allotype antibodies for the capture and detection of IgG2a in the serum of Igh-1b mouse strains.
J Immunol Methods 1989 Dec 20
PMID:An indirect asymmetrical sandwich ELISA using anti-allotype antibodies for the specific and quantitative measurement of mouse IgG2a of Igh-1b allotype. 260 53


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