Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Origin”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 91 records · Page 5Linked to original sources

Origin of interhemispheric fibers in acallosal opossum (with a comparison to callosal origins in rat).

The neocortical origins of the anterior commissure in the acallosal, marsupial opossum were studied with the horseradish peroxidase (HRP) method. Following complete surgical transection of the anterior commissure, HRP was applied directly to the cut fiber tips. This procedure resulted in very large numbers of vividly labeled cells within the neocortex. The labeled cells were plotted and counted for comparison among cytoarchitectonic areas and among cortical layers. For comparative purposes, the neocortical origins of the corpus callosum are studied with the same procedure in the rat. No cytoarchitectonic area was entirely devoid of labeled cells in either species. The concentration of labeled cells throughout the entire neocortex averaged 25.2 cells/0.05 mm3 in opossum and 31.2 cells/0.05 mm3 in rat. The concentrations of labeled cells were correlated for the eight cytoarchitectonic areas common to the two species, though they were different enough in number to be statistically reliable. The distribution of labeled cells both among and within cytoarchitectonic areas was often more homogeneous in opossum than in rat. Although cortical layer 1 had no labeled cells in either species, the distribution of labeled cells across the remaining cortical layers differed sharply between the two species. In opossum, layer 3 had the most labeled cells (averaging 55% of the total number) while layer 5 had considerably less (averaging 12%). In rat, layer 5 had as many labeled cells as layer 3--both layers averaging 43% of the total number of labeled cells. In both species, striate cortex deviated markedly from other cytoarchitectonic areas. Although both species had very few labeled cells in striate cortex, those that were labeled were invariably supragranular in opossum and infragranular in rat. The similarities and dissimilarities in the topographic distribution of the origins of the two types of interhemispheric fiber systems seem to parallel the degree of cortical (and thalamic) differentiation in the two animals. However, the differences in laminar distribution are much greater and in particular, the small contribution of layer 5 in opossum as opposed to rat may well be functionally significant.

Animals↗

Morphology of single vestibulospinal collaterals in the upper cervical spinal cord of the cat: I. Collaterals originating from axons in the ventromedial funiculus contralateral to their cells of origin.

Vestibulospinal neurons in the medial and descending vestibular nuclei have widespread bilateral terminations in the upper cervical spinal cord. These terminations arise from axons travelling in several funiculi, including the ventromedial, ventrolateral, lateral, and dorsolateral funiculi in addition to the dorsal columns. The purpose of the present study was to examine the morphology of single vestibulospinal collaterals which terminate in the upper cervical spinal cord and which originate from axons located in one of these funicular pathways, the ventromedial funiculus, contralateral (cVMF) to their cells of origin in the vestibular nuclei. The 32 collaterals described were selected from two separate sets of experiments which took advantage of different techniques. Nineteen of the collaterals were labelled following Phaseolus vulgaris leucoagglutinin (PHA-L) injections into the medial vestibular nucleus and medial regions of the descending vestibular nucleus. The remaining 13 collaterals originated from physiologically identified vestibulospinal axons that were stained after intra-axonal injections of horseradish peroxidase (HRP). The combined projection of all cVMF axon collaterals spread from laminae V to IX, and included the central cervical nucleus. There was a high degree of variability in the pattern of terminations of individual collaterals. This variability was more pronounced among PHA-L-labelled collaterals than HRP-labelled collaterals whose terminations were restricted to laminae VIII and IX. Some PHA-L-labelled collaterals had terminations which were focused within a single lamina, whereas others had termination zones spanning as many as four laminae. The differences between collaterals were compounded when the characteristics of branching patterns were considered. Some collaterals which occupied similar termination zones had different branching structures.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

The origin of replication of plasmid p15A and comparative studies on the nucleotide sequences around the origin of related plasmids.

Replication of Escherichia coli plasmid p15A was examined by use of a cell extract or a mixture of three purified E. coli enzymes: RNA polymerase; RNAase H; and DNA polymerase I. In each system, replication initiates at any of three consecutive nucleotides located at a unique site. Primer transcription starts 508 bp upstream of the replication origin. The region between 294 and 524 bp upstream of the origin determines the incompatibility property. This region specifies an RNA (RNA I) of about 105 nucleotides that is involved in regulation of primer formation. We compare the nucleotide sequences around the origins of related plasmids p15A, ColE1, pBR322, RSF1030 and CloDF13, and discuss the significance of possible RNA secondary structures in primer formation.

Base Sequence↗

The original pink-eyed dilution mutation (p) arose in Asiatic mice: implications for the H4 minor histocompatibility antigen, Myod1 regulation and the origin of inbred strains.

Allelic variation of the mouse pink-eyed dilution (p) gene in common laboratory strains and wild mice was examined by Southern blot and by polymerase chain reaction. In these assays the original p mutation allele found in strains SJL/J, 129/J, B10.129(21m), P/J and FS/Ei most closely matches an Asian Mus musculus allele, confirming anecdotal accounts of the Asian origin of this mutation. In contrast, the wild-type allele found in other common laboratory strains was apparently derived from Mus domesticus. Analysis of chromosome 7 loci both proximal and distal to the p locus demonstrates that strains SJL/J, 129/J, B10.129(21M), P/J and FS/Ei contain DNA segments of varying length derived from M. musculus. Strains 129/J and B10.129(21M) contain the largest segment of M. musculus-derived DNA (about 5 cM), including the loci Myod1, p, three clustered GABAA receptor subunit loci (Gabrg3, Gabra5 and Gabrb3), and Snrpn. The difference in the species origin of genes from this region of chromosome 7 may underlie the basis of the antigenicity of the minor histocompatibility antigen H4, defined by the strain B10.129(21M), and may account for the enhanced Myod1 activity observed in SJL/J mice.

Alleles↗

Translation control of trpG from transcripts originating from the folate operon promoter of Bacillus subtilis is influenced by translation-mediated displacement of bound TRAP, while translation control of transcripts originating from a newly identified trpG promoter is not.

Bacillus subtilis trpG encodes a glutamine amidotransferase subunit that participates in the biosynthesis of both tryptophan and folic acid. TRAP inhibits translation of trpG in response to tryptophan by binding to a site that overlaps the trpG Shine-Dalgarno sequence, thereby blocking ribosome binding. Similar mechanisms regulate trpP and ycbK translation. The equilibrium binding constants of tryptophan-activated TRAP for the trpG, ycbK, and trpP transcripts were determined to be 8, 3, and 50 nM, respectively. Despite TRAP having a higher affinity for the trpG transcript, TRAP exhibited the least control of trpG expression. The trpG Shine-Dalgarno sequence overlaps the stop codon of the upstream pabB gene, while six of nine triplet repeats within the TRAP binding site are located upstream of the pabB stop codon. Thus, ribosomes translating the upstream pabB cistron could be capable of reducing TRAP-dependent control of TrpG synthesis by displacing bound TRAP. Expression studies using pabB-trpG'-'lacZ fusions in the presence or absence of an engineered stop codon within pabB suggest that translation-mediated displacement of bound TRAP reduces TRAP-dependent inhibition of TrpG synthesis from transcripts originating from the folate operon promoter (P(pabB)). A new trpG promoter (P(trpG)) was identified in the pabB coding sequence that makes a larger contribution to trpG expression than does P(pabB). We found that TRAP-dependent regulation of trpG expression is more extensive for a transcript originating from P(trpG) and that transcripts originating from P(trpG) are not subject to translation-mediated displacement of bound TRAP.

Anthranilate Synthase↗

Comparison of the expression and prognostic significance of differentiation markers between diffuse large B-cell lymphoma of central nervous system origin and peripheral nodal origin.

PURPOSE: Whether diffuse large B-cell lymphoma (DLBCL) of primary central nervous system origin (PCNSL) is biologically different from DLBCL of peripheral nodal origin (NL) remains unclear. The purpose of this study was to compare the expression frequencies and prognostic significance of a panel of cell differentiation markers between these two disease entities. EXPERIMENTAL DESIGN: This study included HIV-unrelated patients with PCNSL (n = 51) and NL (n = 72) treated at four hospitals in Taiwan for whom archival tumor tissue was available. Immunohistochemistry for CD10, BCL-6, MUM-1, vs38c, CD138, and BCL-2 was done. CD10, BCL-6, and MUM-1 expression results were used to classify all cases into the germinal center B-cell (GCB) or the non-GCB subgroup. The prognostic significances of clinical and immunophenotypic markers were evaluated. RESULTS: Nuclear MUM-1 expression was significantly higher in PCNSL than in NL (P < 0.001; 84% versus 53%). PCNSL tumors were more frequently classified into the non-GCB subgroup than NL tumors (P = 0.020; 78% versus 62%). For patients with PCNSL, univariate analysis showed that patients with BCL-6 expression had a trend towards longer survival (P = 0.073; median survival, 25.3 versus 7.3 months), and multivariate analysis showed BCL-6 was an independent prognostic factor (P = 0.026). For patients with NL, both of univariate (P = 0.003) and multivariate analyses (P = 0.002) showed that GCB was significantly associated with favorable survival. CONCLUSION: The higher frequency of non-GCB subclassification, which was mainly contributed by nuclear MUM-1 expression in PCNSL implies that it has a more differentiated cellular origin than NL. BCL-6 expression in patients with PCNSL and GCB subgroup in patients with NL were favorable prognostic factors.

Antibodies, Monoclonal↗

Vertigo of cerebrovascular origin proven by CT scan or MRI: pitfalls in clinical differentiation from vertigo of aural origin.

To get a better insight into the clinical differentiation between vertigo of cerebrovascular origin and of aural origin, we investigated radiologically proven stroke patients who presented with vertigo as an initial clinical manifestation. Of 154 stroke patients, 30 patients with vertigo (20%) had the relevant lesion, demonstrated with the initial computerized tomographic scan (13 patients) or the follow-up magnetic resonance imaging (MRI) study (17 patients) of the brain. Every lesion was in the vertebrobasilar arterial territory; 19 in the cerebellum, 8 in the pons, and 3 in the medulla oblongata. Although 12 of the 30 patients (40%) presented with vertigo in isolation at the onset of stroke, eight patients (27%) developed additional neurologic abnormalities from four hours to seven days later. Patients with isolated vertigo (13%) had the small lesion exclusively in the cerebellum of the PICA medial branch territory. The most frequent accompanying neurological sign was swaying in the cerebellar and medullary lesion, and dysarthria in the pontine lesion. The direction of nystagmus or swaying did not match the lesion side in some patients. Our findings suggest that cerebellar stroke may commonly manifest isolated vertigo or vertigo with swaying mimicking labyrinthine disorder, particularly at the onset of the disease. MRI study and tests for truncal ataxia and lateropulsion may be crucial for the detection of vertigo of cerebrovascular origin.

Adult↗

Anomalous origin of the right vertebral artery: review of the literature and case report of right vertebral artery origin distal to the left subclavian artery.

We present the case of a 57-year-old patient who was admitted to the hospital for preoperative cerebral angiography because of an intraspinal mass at the level of C1 and C2. Angiographic examination revealed an abnormal origin of the right vertebral artery, which normally originates from the right subclavian artery. Thus, the right vertebral artery was the last branch of the supraaortic vessels. We also review herein the incidence of the various anomalous origins of the right vertebral artery in the literature and discuss their potential embryologic development and clinical significance.

Cerebral Angiography↗

[Retroperitoneal germ cell tumor with testicular calcification indicating tiny testicular origin: consideration of the origin of retroperitoneal germ cell tumors: report of two cases].

Two cases of germ cell neoplasm retrospectively considered to have been of testicular origin are reported. Case 1. A 19-year-old male with brain, liver and retroperitoneal tumors was diagnosed with yolk sac tumor by retroperitoneal tumor biopsy. After multidisciplinary treatment, a region of calcification was detected in the left testis on scrotal sonography and left high inguinal orchiectomy was performed. Case 2. A 57-year-old male with neck, lung and retroperitoneal tumors was diagnosed with yolk sac tumor by supraclavicular biopsy. From initial examination, scrotal sonography revealed a small calcified lesion in the right testis. After chemotherapy, high inguinal orchiectomy and retroperitoneal lymphadenectomy were simultaneously performed. Pathologic evaluation of these testicular specimens revealed calcification and a fibrous scar in correspondence with the clinical diagnosis. These changes were considered as scars of the primary testicular tumor due to burned-out tumor or the result of reaction to chemotherapy. Since a primary tumor of testicular origin may exist in the extragonadal germ cell tumor, it is important to examine the intrascrotal contents in detail in the case of so-called extragonadal germ cell tumors with palpably normal testes. In such cases, there are two possible conditions, an occult testicular tumor and a burned-out testicular tumor. We briefly reviewed 42 such cases in the Japanese literature. It appears that there are very few true extragonadal germ cell tumors, and that the possibility of primary testicular origin metastasizing from viable occult testicular tumor or burned-out testicular tumor with spontaneous regression is high in retroperitoneal germ cell tumors.

Adult↗

[Herbological studies on Chinese crude drug Ma-huang. Part 1-On the botanical origin of Ma-huang in ancient China and the origin of Japanese Ma-huang].

The botanical origin of a Chinese crude drug Ma-huang in ancient China and the origin of Japanese Ma-huang were herbologically studied. The results showed that the plants of Ephedra sinica Stapf, E. intermedia Schrenk & C. A. Meyer and E. equisetina Bunge were used as Ma-huang in China, and the first species was considered to be of high quality. The characters of Mao-zhou Ma-huang and Tong-zhou Ma-huang printed in Tu-jing-ben-cao, published in the Song Dynasty in China, were identified as E. likiangensis Florin and E. intermedia, respectively, and both species were recognized as excellent Ma-huang in the Ming Dynasty. The word origin of Katsune-kusa, the Japanese name for Ma-huang in the Heian Era, was etymologically considered as meaning the plant having reddish brown roots. In Japan, the plant of Equisetum ramosissimum Desf. var.japonicum Milde, of the family Equisetaceae, was substituted for Ma-huang in the middle of Edo Era, and it was designated that this action was based on the confusion of Ephedra plants and Equisetum plants those days in China.

China↗

Haplotypes in tribal Indians bearing the sickle gene: evidence for the unicentric origin of the beta S mutation and the unicentric origin of the tribal populations of India.

To determine the origin of sickle cell anemia (SS) in India, we analyzed haplotypes of the beta gene cluster in beta S-carrying individuals belonging to tribal populations living in the Nilgiris region of southern India and complemented the available data on tribes of east-central India. We found that in the Nilgiris tribes chromosomes bearing the beta S gene are linked in 91% of the cases to the "Asian" (Arab-Indian) haplotype (although 25% of the haplotypes had the epsilon polymorphic site negative, making the 5' portion of the haplotype identical with the African Senegal haplotype). These XmnI (+) chromosomes were associated with high G gamma expression (67.2 +/- 5.9%) and a high percentage of Hb F (15.5 +/- 7.9%; range, 6-25.3%). We have similar findings for tribal groups from west-central India (Gujarat). In east-central India we have confirmed the data of others, finding the same haplotype linked to beta S in tribes living in the east (Orissa, Andhra Pradesh). We conclude that the beta S gene in presently isolated and disperse tribal populations in India is associated with one predominant typical haplotype, suggesting a unicentric origin of the mutation in India. In addition, this finding implies a unicentric origin of the tribal populations themselves: The gene must have arisen and spread before tribal dispersion. Furthermore, we find extremely high frequencies of the (-alpha) haplotype in the Nilgiris (0.89) and in Gujarat (0.95). The beta S gene linkage to a high Hb F-expressing haplotype and the high incidence of alpha-thalassemia predict a mild phenotypical expression of sickle cell anemia in India.

Anemia, Sickle Cell↗

[The origin of the eukaryotic cell. I. Historical sources and current state of the concept of symbiotic and autogenic origins of the cell].

The exogenous (symbiotic) conception of the eukaryotic origin is now widely spread. It is based on the recognition of the principle of combination (addition or enclosing) of diverse prokaryotic organisms; so the complicated unicellular eukaryotic organism (eukaryotic cell) was resulted. the principle of combination takes its historical scientific sources from the ideas of Buffon. With reference to the cell this principle was claimed for the first time. In our time the exogenous conception is characterized as a "symbiotic boom", because it is widely used in attempts to explain the origin of all the main organelles of the cell (right up to the micro-bodies). The autogenetic (endogenous) conception is based on the principle of straight phyliation, on the recognition of a successive evolutionary transformation of prokaryotic forms into eukaryotic ones. In this way all the cell organelles may have an endogenous origin. This principle springing from Lamarck has got a contemporary meaning in the doctrine of Darwin. In the next papers the author will present his own analysis and generation of the present day relevant facts to find out which of these two conceptions based on quite different scientific methodological principles may be correct.

Animals↗

[The origin of the eukaryotic cell. IV. The general hypothesis of the autogenous origin of eukaryotes].

The general hypothesis of autogenous (non-symbiotic) origin of the eukaryotic cell summarises some hypotheses explaining possible ways of the origin of main components and organelles of such a cell (the primary unicellular protist). Six hypothesises are suggested. Arising of the eukaryotic surface membrane of protist (cell) as a result of modification of its lipidoacidic composition, when most of synblocks and ensembles of eukaryotic enzymes sink into the cytoplasm (due to membrane vesiculation). Establishment of eukaryotic cytoplasm on the basis of successive formation of two locomotory-supporting apparates: the primary one (microtrabecular system), and the second one (cytoskeleton). Arising of the nucleus from a polyheteronomous nucleoid of proeukaryotes. A combinatorical hypothesis of mitosis formation. Polyheteronucleoid hypothesis of the origin of the mitochondria and chloroplasts. Arising of the flagellum from the contractile tentacle-like organelle, whose axoneme is made of single microtubules. A close interrelation and interaction in the process of evolution is noted between surface membranes, the cytoplasm and the nucleus. In accord a principles of block-construction and heterochrony (see: Seravin, 1986r), the author explains the preservation of prokaryotic signs of organization in some components (and organelles) of eukaryotic cell (and protists).

Aerobiosis↗

Probable clonal origin of aldosteronomas versus multicellular origin of parathyroid "adenomas".

Adrenocortical adenomas causing hyperaldosteronism in two women heterozygous at the X chromosome-linked glucose-6-phosphate dehydrogenase (G-6-PD) locus exhibited only one G-6-PD isoenzyme. This finding suggests a clonal development for these benign tumors and contrasts with the multicellular origin of parathyroid adenomas reported in three patients from our institution in 1977 and found subsequently in seven other hyperparathyroid women whose cases are reported here. One of these seven patients had hereditary hyperparathyroidism. In this case each of three glands removed showed both A and B G-6-PD isoenzymes in similar ratios as were found in normal tissues. The multicellular origin of hereditary hyperparathyroidism is compatible with the concept of parathyroid lesions being manifestations of the first genetic event in Knudson's two-mutational-event theory for the initiation of cancer. The multicellular origin of sporadic parathyroid tumors suggest that they are caused by some factors stimulating many cells in the parathyroid glands. The young average age of onset of eight cases of parathyroid cancer from five families with hereditary hyperparathyroidism in the literature is also compatible with Knudson's theory. G-6-PD studies of other aldosteronomas, parathyroid tumors, and other endocrine neoplasms may provide important information about the pathogenesis of these conditions.

Adenoma↗

Prevalence and origin of de novo duplications in Charcot-Marie-Tooth disease type 1A: first report of a de novo duplication with a maternal origin.

Charcot-Marie-Tooth disease (CMT) is the most common inherited peripheral neuropathy. Sporadic cases of CMT have been described since the earliest reports of the disease. The most frequent form of the disorder, CMT1A, is associated with a 1.5-Mb DNA duplication on chromosome 17p11.2, which segregates with the disease. In order to investigate the prevalence of de novo CMT1A duplications, this study examined 118 duplication-positive CMT1A families. In 10 of these families it was demonstrated that the disease had arisen as the result of a de novo mutation. By taking into account the ascertainment of families, it can be estimated that > or = 10% of autosomal dominant CMT1 families are due to de novo duplications. The CMT1A duplication is thought to be the product of unequal crossing over between parental chromosome 17 homologues during meiosis. Polymorphic markers from within the duplicated region were used to determine the parental origin of these de novo duplications in eight informative families. Seven were of paternal and one of maternal origin. This study represents the first report of a de novo duplication with a maternal origin and indicates that it is not a phenomenon associated solely with male meioses. Recombination fractions for the region duplicated in CMT1A are larger in females than in males. That suggests that oogenesis may be afforded greater protection from misalignment during synapsis, and/or that there may be lower activity of those factors or mechanisms that lead to unequal crossing over at the CMT1A locus.

Charcot-Marie-Tooth Disease↗

The origin recognition complex marks a replication origin in the human TOP1 gene promoter.

The locations of the origin recognition complex (ORC) in mammalian genomes have been elusive. We have therefore analyzed the DNA sequences associated with human ORC via in vivo cross-linking and chromatin immunoprecipitation. Antibodies specific for hOrc2 protein precipitate chromatin fragments that also contain other ORC proteins, suggesting that the proteins form multisubunit complexes on chromatin in vivo. A binding region for ORC was identified at the CpG island upstream of the human TOP1 gene. Nascent strand abundance assays show that the ORC binding region coincides with an origin of bidirectional replication. The TOP1 gene includes two well characterized matrix attachment regions. The matrix attachment region elements analyzed contain no ORC and constitute no sites for replication initiation. In initial attempts to use the chromatin immunoprecipitation technique for the identification of additional ORC sites in the human genome, we isolated a sequence close to another actively transcribed gene (TOM1) and an alphoid satellite sequence that underlies centromeric heterochromatin. Nascent strand abundance assays gave no indication that the heterochromatin sequence serves as a replication initiation site, suggesting that an ORC on this site may perform functions other than replication initiation.

Base Sequence↗

Human origin recognition complex binds to the region of the latent origin of DNA replication of Epstein-Barr virus.

Epstein-Barr virus (EBV) replicates in its latent phase once per cell cycle in proliferating B cells. The latent origin of DNA replication, oriP, supports replication and stable maintenance of the EBV genome. OriP comprises two essential elements: the dyad symmetry (DS) and the family of repeats (FR), both containing clusters of binding sites for the transactivator EBNA1. The DS element appears to be the functional replicator. It is not yet understood how oriP-dependent replication is integrated into the cell cycle and how EBNA1 acts at the molecular level. Using chromatin immunoprecipitation experiments, we show that the human origin recognition complex (hsORC) binds at or near the DS element. The association of hsORC with oriP depends on the DS element. Deletion of this element not only abolishes hsORC binding but also reduces replication initiation at oriP to background level. Co-immunoprecipitation experiments indicate that EBNA1 is associated with hsORC in vivo. These results indicate that oriP might use the same cellular initiation factors that regulate chromosomal replication, and that EBNA1 may be involved in recruiting hsORC to oriP.

Animals↗