GLORIA

GEOMAR Library Ocean Research Information Access

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Polymer and Materials Science  (7)
  • Angiotensin II  (2)
  • Na+/H+ antiport  (2)
  • Organic Chemistry
  • 1990-1994  (12)
Document type
Publisher
Years
Year
  • 1
    ISSN: 1432-1440
    Keywords: Angiotensin II ; Insulin ; Smooth muscle cell ; Vascular
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Hypertension has a high prevalence among subjects with decreased insulin sensitivity and/or hyperinsulinemia. Furthermore, angiotensin II plays a pivotal role in the regulation of vascular tone and is known to induce hypertrophy and/or hyperplasia in vascular smooth muscle cells. In the present study, the effect of insulin on angiotensin II induced smooth muscle cell growth (Wistar-Kyoto rat) was investigated. Cell growth was assessed by the measurement of [3H]thymidine incorporation into cell DNA. Insulin in a concentration range of 1.7 × 10−10–1.7 × 10−6 M lacked any effect on cell DNA synthesis. However, insulin enhanced the angiotensin 11 induced DNA synthesis in a concentration-dependent manner. This effect was similar in cells with a weak and in cells with a marked response in DNA synthesis to stimulation with 100 nM angiotensin 11. In conclusion, insulin is able to enhance angiotensin 11 induced DNA synthesis and may therefore function as a growth cofactor in vascular smooth muscle cells.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1432-1440
    Keywords: Na+/H+ antiport ; Hypertension ; Diabetic nephropathy ; Hereditary factors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The incidence of diabetic nephropathy in patients with insulin-dependent diabetes mellitus (IDDM) may depend on factors other than the quality of diabetes control. Hypertension is an additional factor associated with a high degree of renal involvement in IDDM. One abnormality consistantly observed in various tissues of patients with essential hypertension is enhanced activity of the Na+/H+ antiport. In the present study we have therefore studied platelet antiport activity in 41 healthy subjects (control), in 22 patients with untreated essential hypertension (EH), and in 35 normotensive IDDM patients (type 1). Of these patients 17 exhibited signs of diabetic nephropathy (group 1) while 18 had no evidence for renal involvement of IDDM in spite of a duration of IDDM of at least 10 years (group 2). The two IDDM patient groups were undistinguishable with respect to age, body mass index, and arterial blood pressure (group 1, 117.9±2.4/78.4±1.5 mmHg; group 2, 113.9±3.6/76.1±1.8 mmHg). Antiporter activity was determined from the rate of cell volume changes induced by propionic acid. Platelet Na+/H+ exchange activity averaged 23.43±0.43 10−3·s−1 in control subjects and was markedly elevated in EH (28.38±0.62 10−3·s−1 P〈0.01). Antiport activity in group 2 patients without nephropathy averaged 24.54±0.57 10−3·s−1 and was undistinguishable from the control group. However, platelet Na+/H+ antiport activity was significantly stimulated in group 1 patients with nephropathy as compared to group 2(26.95±0.73 10−3. s−1 ; P〈0.025). Our results show that renal involvement in IDDM is associated with enhanced activity of the platelet Na+/H+ antiport.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1432-1440
    Keywords: Angiotensin II ; Diltiazem ; Mitogenic effect ; Nifedipine ; Platelet-derived growth factor ; Vascular smooth muscle cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Structural changes within the blood vessel wall such as hyperplasia and hypertrophy of vascular smooth muscle cells are important factors in the pathogenesis of hypertension. Humoral growth factors such as angiotensin II (AII) and platelet-derived growth factor BB (PDGF-BB) may participate in the remodelling of the blood vessel wall. Whether and by which mechanisms antihypertensive treatment is capable of influencing the structural blood vessel alterations to date remains unclear. In the present study, the effect of nifedipine and diltiazem on AII- and PDGF-BB-induced vascular smooth muscle cell proliferation was examined. Nifedipine and diltiazem at a concentration of 10 μM did not affect baseline DNA synthesis in isolated vascular smooth muscle cells in culture. AII (final concentration 100 nM) and PDGF-BB (50 ng/ml) stimulated DNA synthesis by approximately 9.0- and 4.6-fold, respectively. Both AII- and PDGF-BB-induced DNA synthesis was significantly blunted by diltiazem and nifedipine in a concentration of 10 μM, while no significant influence was seen with concentrations from 10 nM up to 1 μM. In contrast, no significant influence of these drugs could be observed on fetal calf serum 5%-induced DNA synthesis. The findings indicate that calcium antagonists possess antimitogenic potential and that they may thus contribute to the regression of structural changes of the blood vessels associated with hypertension.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1432-1440
    Keywords: Cell volume regulation ; Hypertonicity ; Lymphocytes ; Na+/H+ antiport ; Saline infusion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The Na+/H+ antiport is a membrane transport protein that extrudes intracellular protons in exchange for extracellular sodium. Some details of its physiological and pathophysiological role remain poorly defined. Experimental evidence suggests that the antiporter is involved in the regulation of cell volume. In the present study, we therefore investigated the activity of the lymphocyte Na+/H+ antiport in nine healthy volunteers following acute hypertonic (2.5%) saline infusion (4 mmol NaCl/kg over 120 min). Antiport activity was measured after acidifying the cells with Na+ propionate (5–40 mM) using the fluorescent dye bis-carboxyethyl carboxyfluorescein. Hypertonic saline induced significant increases in plasma osmolality (308.4±2.3 vs. 293.5±2.7 mOsm/kg; P〈0.01), serum Na+ (150.8±3.7 vs. 138.9±0.5 mmol/kg; P〈0.01), and Cl− concentrations (118.0±3.9 vs. 101.1±1.0 mmol/kg; P〈0.01). Extracellular hypertonicity was followed by a stimulated activity of the lymphocyte Na+/H+ antiport with an increase in the apparent V max values from 2.44±0.16 to 3.27±0.34 10−3 s−1 (P〈0.01) and a slight rise in pK from 6.81±0.03 to 6.87±0.03 (P〈0.05) after hypertonic saline. In addition to antiport activation, cytosolic alkalinization was observed with cytosolic pH values averaging 6.90±0.02 before and 6.99±0.02 (P〈0.01) after hypertonic saline. Our results show for the first time that acute extracellular hypertonicity in man due to hypertonic NaCl loading is associated with a stimulated lymphocyte Na+/H+ antiport activity and cytosolic alkalinization.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Separation and Quantitation of All Eight Stereoisomers of α-Tocopherol by ChromatographyThe results of the analysis of several derivatives of (all-rac)-α-tocopherol by HPLC on a chiral stationary phase and by capillary GC on a achiral stationary phase are reported. Consecutive application of both methods to the ethyl-ether derivative allows the separation and quantification of all eight possible stereoisomers of (all-rac)-α-tocopherol.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 0009-286X
    Keywords: Dosieren ; Schüttguttechnik ; Schneckendosierer ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Chemie Ingenieur Technik - CIT 65 (1993), S. 1088-1090 
    ISSN: 0009-286X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 0009-286X
    Keywords: Oszillierende Verdrängerpumpen ; Druckschwingungen ; Pulsationsdämpfung ; Blenden ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 0009-286X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Developments in dosage of bulk solids. Dosage of bulk solids is a fast developing field of process- and production automation. Developments are determined directly by the current demands of the production process, with the properties of the bulk solids and the process itself playing an important role. A survey of proven dosage techniques from the viewpoint of the operating principles, properties, applications, and limitations demonstrates the great variety of problem solutions. An important difference between the individual dosage techniques is the nature and accuracy of mass limitation. The most accurate techniques are the gravimetric dosage methods, with discontinuous weighing giving the greatest accuracy. Developments have been greatly influenced by the state of weighing cell techniques, weighing electronics and computer engineering. The development of measured data acquisition and processing of control, and of instrumentation are described, compared, and assessed. A trend towards system responsibility and development on the part of manufacturers is noted. A accurate dosage of bulk solids requires constant flow of the solids and finely adjustable control devices. The principal interferences in bulk solids flow and measures for their avoidance are shown by means of examples. Successful solution of dosage tasks ultimately requires agreement between manufacturers and processors with regard to definition, determination, and control of dosage accuracy during calibration and during long term operation.
    Additional Material: 20 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Chemie Ingenieur Technik - CIT 64 (1992), S. 784-785 
    ISSN: 0009-286X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...