Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0432222 (SEM)
 47,337 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An epidemiological study was conducted in the market town of March, Cambridgeshire, to assess the quantitative importance of cooking and table salt to total dietary salt intake by the use of a fused mixture of lithium carbonate and sodium chloride. Men and women aged 20-60 participated in a 12 day study with sequential 24 h urine collections to assess salt sources over a 7 day period. Total salt consumption estimated from urinary chloride excretion amounted to 10.6 +/- 0.55 (SEM) g in 33 men and 7.4 +/- 0.29 (SEM) g in 50 women. The cooking salt eaten was only 0.45 +/- 0.09 (SEM) g in men and women, with men eating more table salt (0.77 g/day) than women (0.46 g/day). Discretionary sources, i.e. cooking and table salt use, contributed only 15% to the total intake. Salt from manufacturing foods and catering in purchased food therefore provided on average 85% of total salt intake. These results are consistent even when an allowance is made for the slightly poorer pouring quality of the lithium-tagged salt. The importance of food as a source of salt was reflected in the significant relationship between the weight of the individual and the amount of salt eaten (for males P less than 0.05 and for females P less than 0.001). Cooking salt consumption did not relate to the amount of salt derived from purchased food nor did table salt use relate to the amount of salt in cooked foods.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:An assessment of the sources of dietary salt in a British population. 380 26

The development of an analytical method for the determination of brain tryptamine using capillary gas chromatography mass spectrometry (selected ion monitoring) is presented. The method involves solvent extraction of brain homogenates and further derivatization (pentafluoropropionyl derivatives) of the dried extracts. Gas chromatographic analysis is performed using a bonded phase silica fused capillary column. Selected monitoring of m/z 289 and 292 (isotope dilution technique) allows the determination of tryptamine in adult rat brain (450 +/- 73 pg g-1) (means +/- SEM), n = 6.
 ...
PMID:Determination of tryptamine in brain tissue by capillary gas chromatography mass spectrometry (selected ion monitoring). 672 86

Guinea pigs, which were either anesthetized (A) or conscious (U), were exposed to four 2 h sessions of broad-band noise of 96 dB SPL. Cochlear microphonics and N1 thresholds were measured prior to killing from 1 to 13 days later. The cochleas were examined by SEM and by section. The U series suffered less N1 threshold loss and recovered within 10-13 days, while the large initial loss in the A series did not completely reverse within the period of study. Initially, the IHC stereocilia in the basal half of the cochlea showed marked bending, the affected area being somewhat more extensive in the A group. These hairs gradually recovered, although not progressively. On the other hand, the disturbance to OHC stereocilia, which appeared to be less pronounced early on and was more apically centered, developed over time into marked permanent damage. The outermost row consistently showed the greatest effect with hairs becoming elongated or fused, and occasionally lost altogether. Susceptibility to noise varied between individuals of both groups. The recovery of N1 threshold was concomitant with the recovery of the erectness of the IHC hairs.
 ...
PMID:Effects on guinea pig cochlea from exposure to moderately intense broad-band noise. 688 48

T lymphocytes express a unique I-A subregion-controlled surface molecule that is not expressed on B lymphocytes. We produced antisera and monoclonal antibodies recognizing this structure. Exhaustive B cell adsorption (A.TH X B10.HTT)F antiserum, produced against activated A.TL T cells, left antibodies that bind an I-Ak specificity on some B10.A(4R) T lymphocytes (11 +/- 2%, mean +/- SEM). Similarly, exhaustive B cell adsorption of (A/J X B10.MBR)F antiserum, produced against activated B10.A(5R) cells, left antibodies specific for an I-Ab determinant on B10.A(5R)T cells (17 +/- 2%). We fused A.TL-immune (A.TH X B10.HTT)F splenocytes with NS-1 myeloma cells and identified antibody-producing hybrid cells by a fluorescent enzyme-linked immunosorbent microassay described herein. Eight monoclonal antibodies were selected; these lyse 7--26% of peripheral T cells from I-Ak strains. Thymocytes and bone marrow cells do not express the I-Ak T cells determinant. Exhaustive B cell adsorption did not remove I-Ak T cell-specific monoclonal antibodies.
 ...
PMID:Murine T cell-specific Ia antigens: monoclonal antibodies define an I-A-encoded T lymphocyte structure. 698 Apr 12

An injury to adult mammalian skeletal muscle is followed by regeneration, which involves a process believed to be similar to the differentiation of muscle fibres in the embryo. The origin of these differentiating myogenic cells is conjectural. The aim of the present study was to examine the source of myogenic cells and the process of myogenesis in adult skeletal muscle. Mononucleated cells were released from adult rat leg muscle mince after incubation with 0.1% pronase for 50-60 minutes at 37 degrees C. The ultrastructural studies revealed that the freshly dissociated mononucleated cells consisted of at least two populations of cells: myogenic satellite cells and non-myogenic fibroblastic cells. These cells were plated in growth media at various densities in cell culture dishes and incubated for 3 weeks in a balanced air atmosphere at 37 degrees C. The culture was routinely examined with a phase contrasted microscope for evidence of myogenic activities of the plated cells. At selected time intervals, the cell cultures were processed for autoradiography and scanning and transmission electron microscopy (SEM and TEM). Attachment of cells to the dish began soon after plating, with flattening of some non-muscle cells. The round- to spindle-shaped cells, indicative of myoblasts, began to appear within 24 hours. DNA synthesis and cell proliferation were observed in myogenic and non-myogenic cells within 24 hours of culture. SEM revealed that at 72 hours some myoblasts aligned and fused with one another, forming myotubes. Quantitation of autoradiographs indicated that the maximum number of labelled myotubes were present in the 3 days old culture, and thereafter, the labelled myotubes decreased in number and were absent in the 7 days old culture. Within 5-7 days the myotubes became larger and showed contractility. TEM of 6 to 21 day culture revealed that the myotubes contained well differentiated myofibrils, T-tubules and sarcoplasmic reticulum. It was evident from our studies that the mononucleated cells, having satellite cell morphology, were capable of differentiating into fully formed muscle fibres. This study lends support to the satellite cell hypothesis for regeneration of the skeletal muscle.
 ...
PMID:Myogenesis in adult mammalian skeletal muscle in vitro. 727 84

The development of the branchial arch region was studied in mouse embryos at the age of 10-13 days after conception [end of embryonal day (ED) 10 to end of ED 13] and in rat embryos at the age oa 1-14 days after conception (end of ED 11 to nd of ED 14) using SEM and serial semithin sections. Special attention was paid to the development of the cervical sinus and the branchial operculum. In both rodents, a typical operculum was not found. Instead, the caudal branchial arch region was remodeled by a rapid growth of the second branchial arch, the retrobranchial ridge and the epipericardial ridge, thus forming a progressively deeper grove in this region, the sinus cervicalis. The epithelium of the fourth and sixth branchial arches participated in the formation of the vagus placode, which in later stages was depressed into a grove dorsally and lost its connection with the surface. Finally, the second branchial arch and the cardiac bulge fused compressing the third branchial arch, the second and third branchial grooves and the aperture of the vagus placode. A typical vesicula cervicalis, lined by ectodermal epithelium and collecting the second, third and fourth branchial grooves and the glossopharyngeal and vagus placodes, was not found. However, single or multiple slit-like lumina may persist within the epithelial remnants of the second and third branchial grooves and the vagus placode.
 ...
PMID:[Branchial arch development in the rat and mouse. I. Development of the sinus cervicalis and operculum]. 728 92

Detailed SEM observations of the changes in cellular morphology, arrangements, and contacts that occur during the process of somite formation were made in two species of urodele amphibians, Ambystoma mexicanum and Pleurodeles waltlii, and one species of anuran amphibian, Rana sphenocephala. After fixation, embryos were fractured transversely, horizontally, and parasagittally, and the intrasomitic cellular arrangement pattern was examined with the SEM. It was found that Ambystoma and Pleurodeles embryos followed exactly the same development sequence in rosette formation and myoblast fusion. Rana somites did not, however, appear to form rosettes. Those myotomal cells underwent fusion immediately after a few segmentations occurred. Patterns of cellular rearrangement were also described during urodele rosette formation at the time of somite segmentation and during myoblast fusion. Extensive changes in cell shape and orientation appeared to occur during those processes. When cells changed their orientation, they often exhibited a triangular configuration. Probable roles of these triangular-shaped cells in rosette formation and myoblast fusion are discussed. During the initial period of myoblast or myotomal cell fusion, cells first send out specialized cell processes and then establish their cell-cell contacts. The establishment of such contacts eventually leads to tight membrane appositions and fusion. Since myoblast fusion appeared to occur between two cells which were tandemly arranged in a rosette, the origin of multi-nuclearity in the fused cells is discussed. Finally, comparative analyses of the pattern of somite formation and subsequent muscle development were made between different species of amphibians. The possibility is discussed that patterns of somitogenesis may provide useful indicators for determining how different families of amphibians evolved.
 ...
PMID:Comparative analysis of amphibian somite morphogenesis: cell rearrangement patterns during rosette formation and myoblast fusion. 733 6

Chronic infusion of atrial natriuretic peptide (ANP) has been shown to cause natriuresis, diuresis, and hypotension in rats and humans. We explored the effect of a continuous supply of ANP by somatic ANP delivery on genetically hypertensive rats. A DNA construct containing the human ANP gene fused to the Rous sarcoma virus 3'-long terminal repeat (RSV-LTR) was injected intravenously into spontaneously hypertensive rats (SHR) through the tail vein. Expression of human ANP in SHR was identified in the heart, lung, and kidney by radioimmunoassay and reverse transcription-polymerase chain reaction followed by Southern blot analysis. A single injection of naked ANP plasmid DNA (12.3 kb) caused a significant reduction of systemic blood pressure in young SHR (4 weeks old), and the effect continued for 7 weeks. The differences were significant at 1 to 2 weeks (n = 6, P < .05) and 3 to 6 weeks after injection (n = 6, P < .01) A maximal blood pressure reduction of 21 mm Hg in young SHR was observed 5 weeks after injection with ANP DNA (159.4 +/- 3.02 mm Hg, mean +/- SEM, n = 6) compared with SHR injected with vector DNA alone (180.2 +/- 3.02 mm Hg, mean +/- SEM; n = 6; P < .01). Somatic gene delivery of human ANP DNA had no effect on the blood pressure of adult SHR (12 weeks old). After ANP gene delivery, there were significant increases in urinary volume and urinary potassium output (n = 6, P < .05) but not in body weight, heart rate, water intake, urinary sodium output, urinary creatine, and urinary protein.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Human atrial natriuretic peptide gene delivery reduces blood pressure in hypertensive rats. 1467 5

The precise molecular abnormalities that cause primary cortisol resistance have not been completely described. In a subject with primary cortisol resistance we have observed glucocorticoid receptors (hGR) with a decreased affinity for dexamethasone. We hypothesize that a mutation of the hGR glucocorticoid-binding domain is the cause of cortisol resistance. Total RNA isolated from the index subject's mononuclear leukocytes was used to produce first strand hGR cDNAs, and the entire hGR cDNA was amplified in segments and sequenced. At nucleotide 2,317 we identified a homozygous A for G point mutation that predicts an isoleucine (ATT) for valine (GTT) substitution at amino acid 729. When the wild-type hGR and hGR-Ile 729 were expressed in COS-1 cells and assayed for [3H]-Dexamethasone binding, the dissociation constants were 0.799 +/- 0.068 and 1.54 +/- 0.06 nM (mean +/- SEM) (P < 0.01), respectively. When the wild-type hGR and hGR-Ile 729 were expressed in CV-1 cells that were cotransfected with the mouse mammary tumor virus long terminal repeat fused to the chloramphenicol acetyl transferase (CAT) gene, the hGR-Ile 729 conferred a fourfold decrease in apparent potency on dexamethasone stimulation of CAT activity. The isoleucine for valine substitution at amino acid 729 impairs the function of the hGR and is the likely cause of primary cortisol resistance in this subject.
 ...
PMID:A mutation of the glucocorticoid receptor in primary cortisol resistance. 768 92

This investigation was conducted to evaluate the potential capacity of the human fetal membranes-decidua parietalis, and in particular the chorion laeve, to degrade uterotonins that are produced in amnion, are present in amniotic fluid, or both. The four uterotonins that have been evaluated most frequently as myometrial contractants potentially involved in the initiation of human parturition are prostaglandins, oxytocin, endothelin-1, and platelet-activating factor. We assessed the levels of mRNA and the specific activities (SAs) of enkephalinase (the plasma membrane endopeptidase that degrades endothelins) and prostaglandin dehydrogenase (PGDH) in human fetal membranes, i.e. amnion and chorion leave, and in decidua parietalis. The SA of oxytocinase (which inactivates oxytocin) in these tissues also was determined. The SA of enkephalinase in chorion laeve from all anatomical sites (singleton and diamnionic-dichorionic twin placentae) in all pregnancies studied (mean +/- SEM, 95 +/- 7.9 ng/min.mg protein; n = 28) is similar to that in human fetal kidney (89.5 +/- 2.8; n = 6). Kidney tissue is believed to be one of the richest sources of enkephalinase. The SAs of enkephalinase in amnion (18.3 +/- 2.3 nmol/min.mg protein; n = 29) and in decidua parietalis (31.8 +/- 6.7; n = 20) also were high, but significantly less than that in chorion leave. The level of enkephalinase mRNA in chorion laeve in singleton pregnancies is high, as is the SA of enkephalinase (111.9 +/- 10.6 nmol/min.mg protein; n = 17). In paired chorion laeve tissues from five diamnionic-dichorionic twin placentae, the SAs of enkephalinase in reflected chorion laeve (74 +/- 12.8; P < 0.06 compared with singletons) and fused chorion laeve (64.8 +/- 6.5; P < 0.001 compared with singletons) were similar. The SA of PGDH in reflected chorion leave (46.3 +/- 6.9 nmol/min.mg protein; n = 19) was significantly greater than that in decidua (16 +/- 5.5; n = 15). There was a significant correlation between the levels of PGDH mRNA and PGDH enzyme SA. In fused chorion laeve of diamnionic-dichorionic twin placentae, the SA of PGDH (14.9 +/- 7.3; n = 4) was much less than that in reflected chorion laeve of the same twin pregnancy (70.5 +/- 14.7; n = 4). PGDH mRNA was not detectable in amnion tissue (n = 5) by northern analysis, and the SA of PGDH (< 1.2 +/- 1.0; n = 6) in amnion was undetectable or near the lower limit of assay detection.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Human fetal membrane contribution to the prevention of parturition: uterotonin degradation. 810 36


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>