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)

The gait of men with unilateral hip fusion is somewhat slow, asymmetrical, and arrhythmic as compared with that of normal men. Compensation for absent hip motion is accomplished by increased transverse and sagittal rotation of the pelvis, increased motion in the sound hip, and increased flexion of the knee throughout the stance phase on the fused side. Relationships between the fusion position, certain physical traits, and walking performance suggest that the best gait can be expected in young patients who have free motion of the lumbar spine, the sound hip, and the knee on the side of fusion, and who have equal limb lengths and a hip fused in a position that does not include excessive adduction.
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PMID:Walking patterns of men with unilateral surgical hip fusion. 115 10

Virchow (1851) is credited with initially describing calvarial development following premature closure of individual sutures. He noted that resultant compensatory growth occurred perpendicular to the fused suture, resulting in asymmetrical calvarial development. Lambdoid synostosis, whether unilateral, bilateral, or associated with other cranial fusions, is reasonably uncommon. Previous authors report an incidence of less than 10% of all reported cases of premature fusion of the calvarial or skull base sutures. We report 27 patients (20 boys, 7 girls) ranging in age from 3 months to 8 years with unilateral lambdoid craniosynostosis followed over a three-year period. In 19 patients, calvarial reshaping was performed by repositioning a parietooccipital bone flap stabilized with lag-screw fixation to provide an increased radius of curvature to the affected area and to reestablish the resultant craniectomy between the parietooccipital junction and into the posterior fossa retromastoid occipital bone as an appropriate site for growth. Indications for one-stage calvarial reshaping included untreated lambdoid stenosis in older children or a failed simple lambdoid synostectomy after approximately 18 months. Each child experienced significant improvement in calvarial shape and ipsilateral ear position. Although we had no operative complications, two children underwent a second outpatient procedure for removal of hardware palpated by their parents.
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PMID:Surgical correction of unilateral lambdoid synostosis: occipital rotation flap. 139 Dec 41

Skull growth after premature fusion of a single suture was described by Virchow in 1851. He observed that growth was restricted in a plane perpendicular to a fused suture. However, he failed to predict the compensatory growth patterns that produce many of the deformities recognized as features of individual craniosynostosis syndromes. The deformities resulting from premature closure of a coronal, sagittal, metopic, or lambdoid suture can be predicted by the following observations: (1) cranial vault bones that are prematurely fused act as a single bone plate with decreased growth potential; (2) asymmetrical bone deposition occurs mainly at perimeter sutures, with increased bone deposition directed away from the bone plate; (3) sutures adjacent to the stenotic suture compensate in growth more than those sutures not contiguous with the closed suture; and (4) enhanced bone deposition occurs along both sides of a nonperimeter suture that is a continuation of the prematurely closed suture. These four rules were derived by critically examining the clinical deformities observed with each form of craniosynostosis. These rules assume that cranial sutures have the capacity to compensate by depositing bone asymmetrically along their edges. Unequal growth patterns have been demonstrated in the frontonasal suture of rabbits by Selman and Sarnat. In addition, unequal bone deposition has also been demonstrated along the parieto-interparietal suture in albino rats by Baer. Human studies to determine if asymmetrical bone deposition actively occurs along cranial vault sutures in response to a stenotic suture have not been performed, however. It is also unclear whether these four guidelines apply to cranial base abnormalities observed with craniosynostosis. As new radiologic techniques develop to define the configuration of the skull in intricate detail, a skull pattern of growth explaining the pathogenesis of all deformities created by premature fusion of a cranial vault suture may become apparent.
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PMID:Cranial deformation in craniosynostosis. A new explanation. 182 7

Six species of the family Heligmonellidae (Nematoda: Trichostrongyloidea), including 3 new species, are recorded from rodents of the subfamily Murinae in the Ryukyu Archipelago and Taiwan. Heligmonoides ikeharai n. sp. from Tokudaia osimensis muenninki on Mt. Yonaha, Okinawa Island, is characterized by extremely long spicules and hypertrophied ridges in the prevulval region. Heligmonoides taiwanensis n. sp. from Apodemus draco on Mt. Alishan, Taiwan, is distinguished from other members of the genus in having a markedly asymmetrical bursa and stout bursal rays. Heligmonoides alishanensis n. sp. from Niviventer confucianus on Mt. Alishan differs from the allied forms in lacking hypertrophied ridges at the level of the middle of the spicules and in having longer spicules and a smaller body. Nippostrongylus sp. from N. confucianus on Mt. Alishan resembles Nippostrongylus brasiliensis but is distinguishable in that the externolateral ray is almost the same length as the lateroventral ray in the left lobe, and the fused tips of the spicules are thin and straight. Heligmonoides ryukyensis from Mus caroli and Orientostrongylus tenorai from Bandicota indica are first recorded from Taiwan. Heligmonellid nematodes parasitic in wild rodents in these areas are considered to have been introduced with their hosts from the mainlands of China and Japan through land connections in the Pleistocene.
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PMID:Nematodes of the family Heligmonellidae (Trichostrongyloidea) collected from rodents of the Ryukyu archipelago and Taiwan. 238 Aug 55

Skull growth after single suture closure was described in 1851 by Virchow, who noted that growth in the plane perpendicular to a fused suture was restricted. However, this observation failed to predict compensatory growth patterns that produce many of the deformities recognized as features of individual syndromes. The deformities resulting from premature closure of a coronal, sagittal, metopic, or lambdoid suture can be predicted on the basis of the following observations: 1) cranial vault bones that are prematurely fused secondary to single suture closure act as a single bone plate with decreased growth potential; 2) asymmetrical bone deposition occurs mainly at perimeter sutures, with increased bone deposition directed away from the bone plate; 3) sutures adjacent to the prematurely fused suture compensate in growth more than those sutures not contiguous with the closed suture; and 4) enhanced symmetrical bone deposition occurs along both sides of a non-perimeter suture that is a continuation of the prematurely closed suture. These observations regarding growth in craniosynostosis are illustrated with clinical material in this report.
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PMID:Cranial vault growth in craniosynostosis. 291 14

We isolated and delimitated the Drosophila ras2 promoter region, determined its sequence and mapped the transcription units expressed in this region. The results showed that the Drosophila ras2 gene is flanked by another transcription unit, which codes for two larger transcripts, 2.5 and 2.9 kb long. Orientation experiments, in which sense and antisense RNA probes were used, revealed that both these and the ras2 transcripts are synthesized from different DNA strands. Thus, the flanking transcription unit is in the opposite polarity relative to the ras2 gene. The transcription start sites of the ras2 gene and the flanking transcription unit were determined by external primer extension with T4 DNA polymerase and by RNAase-protection assay and were found to be only 94 nucleotides apart. Apparently, the Drosophila ras2 promoter is a bidirectional promoter. Nucleotide sequence analysis revealed that the 5'-end of the ras2 transcript is within an inverted repeat of the insect cap box. TATA- and GC-like boxes were also found. Analysis of direct and inverted repeats in the promoter region suggested that it is asymmetrical. To demonstrate promoter activity, each side of the ras2 bidirectional promoter was fused to the bacterial chloramphenicol acetyltransferase (CAT) gene and tested by transfecting Drosophila Schneider 2 culture cells. Significant CAT activity was obtained with both transcription fusions.
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PMID:A bidirectional promoter is regulating the Drosophila ras2 gene. 341 73

The ultrastructure of the optic and trigeminal nerves of the rat, cryofixed by use of a liquid nitrogen-propane jet, was examined, paying special attention to the myelin sheath and the cytoskeleton of the axoplasm. The cytoskeleton of the axoplasm is formed by a meshwork of neurofilaments and microtubules connected both to each other and also to the cell organelles and axolemma. These cross-linkers are fixed to the longitudinal neurofilaments in a helical arrangement, which could be a morphological substrate for the diverse axonal transport phenomena. The myelin sheath is formed by concentrically apposed membrane pairs, which are not fused together. The corresponding major and intraperiod lines seen using classical electron microscopy are in fact fissures that are obscured by the pattern of the selective deposition of osmium at certain sites and cannot be interpreted as specific structures. The cryofixed myelin membranes have the appearance of predominantly globular subunits arranged in an asymmetrical bilayer. The globular particles are of diverse diameter and occupy varying positions within the membrane. The tight junctions or zonulae occludentes of the myelin are formed by arrays of isolated particles, and consequently the fibril formation seems to be a result of the chemical fixation.
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PMID:Ultrastructural aspects of cryofixed nerves. 405 70

We have located Mu delta 26 sequences straddling the forks in DNA structures which appear during Mu delta 26 replication, i.e., keys, pending keys, dumb- bells , partially fused circles, and asymmetrical forks. This brings additional evidence that these structures are mini-Mu replication intermediates. The possible relationship between these structures and those predicted by the different models formulated to explain transposition in procaryotes is discussed.
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PMID:Localisation of mini-Mu in its replication intermediates. 676 36

During development membranous organelles first appeared in the primary spermatocytes of Ancylostoma. They were derived from the Golgi as two separate components. One component, an electron-dense spheroid, quickly fused with other newly-formed cup-shaped, membranous structures to form the asymmetrical organelles. Initially the membranous organelles had a homogeneous matrix but later became filled with quantities to 6- 8-nm filaments. Following the meiotic reduction divisions each cell assumed a bipolar configuration. The membranous organelles and mitochondria were confined to the broad anterior region while the non-membrane bound nucleus became located in the narrow posterior region. Golgi membranes, endoplasmic reticulum, and numerous ribosomes were sloughed from the main cell body. The filaments lost their association with the membranous organelles and attached to the plasma membrane while the membranous portion of each organelle became progressively more complex and assumed a peripheral position in the cytoplasm. The resulting spermatid, with its condensed, posteriorly-projected nucleus, and broad anterior cytoplasm, had a tadpolelike appearance. Subsequent to deposition in the female uterus the membranous organelles fused with the plasma membrane and the mature spermatozoa became pleomorphic and moved in an ameboid manner. Because the pseudopods in the mature cell originated in those areas where the filaments previously attached to the plasma membrane it is surmised that the filaments consist of, or contain, actin. The significance of the fusion of the membranous organelles with the sperm plasma membrane, however, remains unknown.
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PMID:Development and fate of the membranous organelles in spermatozoa of Ancylostoma caninum. 713 Nov 88

Amyloid beta protein (A beta P) is the 40- to 42-residue polypeptide implicated in the pathogenesis of Alzheimer disease. We have incorporated this peptide into phosphatidylserine liposomes and then fused the liposomes with a planar bilayer. When incorporated into bilayers the A beta P forms channels, which generate linear current-voltage relationships in symmetrical solutions. A permeability ratio, PK/PCl, of 11 for the open A beta P channel was estimated from the reversal potential of the channel current in asymmetrical KCl solutions. The permeability sequence for different cations, estimated from the reversal potential of the A beta P-channel current for each system of asymmetrical solutions, is Pcs > PLi > PCa > or = PK > PNa. A beta P-channel current (either CS+ or Ca2+ as charge carriers) is blocked reversibly by tromethamine (millimolar range) and irreversibly by Al3+ (micromolar range). The inhibition of the A beta P-channel current by these two substances depends on transmembrane potential, suggesting that the mechanism of blockade involves direct interaction between tromethamine (or Al3+) and sites within the A beta P channel. Hitherto, A beta P has been presumed to be neurotoxic. On the basis of the present data we suggest that the channel activity of the polypeptide may be responsible for some or all of its neurotoxic effects. We further propose that a useful strategy for drug discovery for treatment of Alzheimer disease may include screening compounds for their ability to block or otherwise modify A beta P channels.
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PMID:Alzheimer disease amyloid beta protein forms calcium channels in bilayer membranes: blockade by tromethamine and aluminum. 838 Jun 42


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