Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Calcium and Magnesium: Low Passive Permeability and Tubular Secretion in the Mouse Medullary Thick Ascending Limb of Henle's Loop (MTAL) (1996)
    Springer
    The journal of membrane biology 153 (1996), S. 27-35 
    Details
    ISSN: 1432-1424
    Keywords: Key words: Medullary thick ascending limb — Ca2+ transport — Mg2+ transport — Electron microprobe analysis — Passive permeability — ADH
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract. Recent studies from our laboratory have shown that in the mouse and rat nephron Ca2+ and Mg2+ are not reabsorbed in the medullary part of the thick ascending limb (mTAL) of Henle's loop. The aim of the present study was to investigate whether the absence of transepithelial Ca2+ and Mg2+ transport in the mouse mTAL is due to its relative low permeability to divalent cations. For this purpose, transepithelial ion net fluxes were measured by electron probe analysis in isolated perfused mouse mTAL segments, when the transepithelial potential difference (PDte.) was varied by chemical voltage clamp, during active NaCl transport inhibition by luminal furosemide. The results show that transepithelial Ca2+ and Mg2+ net fluxes in the mTAL are not driven by the transepithelial PDte. At zero voltage, a small but significant net secretion of Ca2+ into the tubular lumen was observed. With a high lumen-positive PDte generated by creating a transepithelial bath-to-lumen NaCl concentration gradient, no Ca2+ and Mg2+ reabsorption was noted; instead significant and sustained Ca2+ and Mg2+ net secretion occurred. When a lumen-positive PDte was generated in the absence of apical furosemide, but in the presence of a transepithelial bath-to-lumen NaCl concentration gradient, a huge Ca2+ net secretion and a lesser Mg2+ net secretion, not modified by ADH, were observed. Replacement of Na+ by K+ in the lumen perfusate induced, in the absence of PDte changes, important but reversible net secretions of Ca2+ and Mg2+. In conclusion, our results indicate that the passive permeability of the mouse mTAL to divalent cations is very low and not influenced by ADH. This nephron segment can secrete Ca2+ and Mg2+ into the luminal fluid under conditions which elicit large lumen-positive transepithelial potential differences. Given the impermeability of this epithelium to Ca2+ and Mg2+, the secretory processes would appear to be of cellular origin.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002329900106
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Antioxidant activity of topically applied lycopene (2004)
    Oxford, UK : Blackwell Publishing Ltd.
    Journal of the European Academy of Dermatology and Venereology 18 (2004), S. 0 
    Details
    ISSN: 1468-3083
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background  Ultraviolet (UV) rays cause depletion of the antioxidant substances contained in the epidermis. This is the rationale for the use of topical antioxidant substances.Methods  We studied the protective activity against UV radiation of a product based on lycopene and a product containing a mixture of vitamins E and C. Photostimulation was applied with a solar simulator and the cutaneous response was evaluated instrumentally.Results  The lycopene-based product had a much greater protective ability than the product containing the mixture of vitamins.Conclusions  Lycopene has suitable characteristics to be used successfully in the prevention of cutaneous damage by free radicals. Its antioxidant ability is probably due to its high reductive power.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1468-3083.2004.00850.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Cellular and molecular mechanisms in chronic obstructive pulmonary disease: an overview (2004)
    Oxford, UK : Blackwell Science Ltd
    Clinical & experimental allergy 34 (2004), S. 0 
    Details
    ISSN: 1365-2222
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: In the last decade, the analysis of bronchial biopsies and lung parenchyma obtained from chronic obstructive pulmonary disease (COPD) patients compared with those from smokers with normal lung function and non-smokers has provided new insights on the role of the different inflammatory and structural cells, their signalling pathways and mediators, contributing to a better knowledge of the pathogenesis of COPD. This review summarizes and discusses the lung pathology of COPD patients with emphasis on inflammatory cell phenotypes that predominate in different clinical conditions. In bronchial biopsies, a cascade of events takes place during progression from mild-to-severe disease. T lymphocytes, particularly CD8+ cells and macrophages are the prevalent inflammatory cells in the lung of healthy smokers and patients with mild COPD, while total and activated neutrophils predominate in severe COPD. The number of CD4+, CD8+ cells and macrophages expressing nuclear factor-kappa B (NF-κB), STAT-4 and IFN-γ proteins as well as endothelial adhesion molecule-1 in endothelium is increased in mild/moderate disease. In contrast, activated neutrophils (MPO+ cells) and increased nitrotyrosine immunoreactivity develops in severe COPD. In bronchial biopsies obtained during COPD exacerbations, some studies have shown an increased T cell and granulocyte infiltration. Regular treatment with high doses of inhaled glucocorticoids does not significantly change the number of inflammatory cells in bronchial biopsies from patients with moderate COPD. The profile in lung parenchyma is similar to bronchial biopsies. ‘Healthy’ smokers and mild/moderate diseased patients show increased T lymphocyte infiltration in the peripheral airways. Pulmonary emphysema is associated with a general increase of inflammatory cells in the alveolar septa. The molecular mechanisms driving the lymphocyte and neutrophilic prevalence in mild and severe disease, respectively, needs to be extensively studied. Up-regulation of pro-inflammatory transcription factors NF-κB and STAT-4 in mild, activated epithelial and endothelial cells in the more severe disease may contribute to this differential prevalence of infiltrating cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2222.2004.02030.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Decreased T lymphocyte infiltration in bronchial biopsies of subjects with severe chronic obstructive pulmonary disease (2001)
    Oxford, UK : Blackwell Science, Ltd
    Clinical & experimental allergy 31 (2001), S. 0 
    Details
    ISSN: 1365-2222
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background Studies on the inflammatory process in the large airways of patients with mild/moderate COPD have shown a prevalent T lymphocyte and macrophage infiltration of the bronchial mucosa. However, bronchial inflammation in more severe disease has not been extensively studied.Objective The aim of the present study was to characterize the lymphocyte infiltration in the bronchial mucosa of subjects with severe, compared to mild, COPD, and to examine the relationship between airflow limitation and T lymphocyte numbers in the bronchial mucosa.Methods We examined bronchial biopsies obtained from nine smokers with severe airflow limitation, nine smokers with mild/moderate airflow limitation and 14 smokers with normal lung function. Immunohistochemical methods on cryostat sections were used to assess the number of CD3+, CD4+, CD8+ cells and the number of CD3+ cells coexpressing the chemokine receptor CCR5 (CCR5+CD3+) in the subepithelium.Results Subjects with severe COPD had lower numbers of CD3+, CD8+ and CCR5+CD3+ cells than mild/moderate COPD (P 〈 0.012, P 〈 0.02 and P 〈 0.02, respectively) and control smokers (P 〈 0.015, P 〈 0.005 and P 〈 0.015, respectively). In subjects with airflow limitation the number of CD3+ and CD8+ cells was inversely correlated with the degree of airway obstruction (r = 0.59, P 〈 0.015 and r = 0.52, P 〈 0.032, respectively).Conclusions Bronchial inflammation in severe COPD is characterized by lower numbers of CD3+ and CD8+ cells and decreased numbers of CD3+ cells coexpressing the chemokine receptor CCR5. T lymphocyte infiltration is inversely correlated with the degree of airflow limitation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2222.2001.01098.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Effect of testosterone on purine synthesis de novo in rat perineal muscle in vivo
    Amsterdam : Elsevier
    Biochimica et Biophysica Acta (BBA)/General Subjects 926 (1987), S. 1-7 
    Details
    ISSN: 0304-4165
    Keywords: (Rat muscle) ; Purine synthesis ; Testosterone
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology , Medicine , Physics
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0304-4165(87)90176-0
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Quantitative separation of uric acid and allantoin from rat liver tissue
    Amsterdam : Elsevier
    Biochimica et Biophysica Acta (BBA)/General Subjects 1117 (1992), S. 1-6 
    Details
    ISSN: 0304-4165
    Keywords: (Rat liver) ; Allantoin ; Formate ; Purine catabolism ; Separation procedure ; Uric acid
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology , Medicine , Physics
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0304-4165(92)90154-M
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Synthesis and evaluation of 2-(5-methoxythiophen-3-yl)ethylamines as potential dopamine agonists
    Amsterdam : Elsevier
    European Journal of Medicinal Chemistry 29 (1994), S. 423-429 
    Details
    ISSN: 0223-5234
    Keywords: N-substituted 2-(5-methoxythiophen-3-yl)ethylamines ; dopamine D"1 and D"2 receptor binding ; dopaminergic activity ; synthesis
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1016/0223-5234(94)90069-8
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Serum levels of myoglobin in aged thyreopathic patients
    Amsterdam : Elsevier
    Archives of Gerontology and Geriatrics 1 (1982), S. 125-128 
    Details
    ISSN: 0167-4943
    Keywords: hyperthyroidism ; hypothyroidism ; myoglobin
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Medicine
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0167-4943(82)90012-7
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Cellular adaptation of the mouse cortical thick ascending limb of Henle's loop (CTAL) to dietary magnesium restriction: enhanced transepithelial Mg2+ and Ca2+ transport (2000)
    Springer
    Pflügers Archiv 439 (2000), S. 765-771 
    Details
    ISSN: 1432-2013
    Keywords: Cortical thick ascending limb Low-Mg2+ diet Mg2+ transport Microperfusion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract. Mice aged 4 or 8 weeks were fed with a low-Mg2+ diet for 1, 2, 3 or 4 days. After 1 day of diet, the urinary excretion of Mg2+ and Ca2+ was strongly reduced in both animal groups (4 and 8 weeks), accompanied by a significant fall in plasma Mg2+ concentration and an increase in urinary volume. This profile persisted after 2, 3 or 4 days of dietary Mg2+ restriction. After 1 day of diet, transepithelial ion net fluxes of Na+, Cl–, Ca2+ and Mg2+ (J Na, J Cl, J Ca, J Mg) measured in vitro from isolated perfused cortical thick ascending limbs (CTALs) of these animals remained unchanged. After 2 days of diet, measurements of J Ca and J Mg in isolated perfused CTALs showed that transepithelial Mg2+ and Ca2+ reabsorption were enhanced in CTALs from Mg2+-depleted, 8-week-old animals, whereas transepithelial Mg2+ and Ca2+ transport were not altered in 4-week-old mice. J Na and J Cl and the transepithelial potential (PDte) were not modified in CTALs from either animal group. Our results suggest that a low-Mg2+ diet leads to urinary retention of Mg2+ and Ca2+ which is most likely due to increased Mg2+ and Ca2+ transport in the CTAL. Furthermore, in response to dietary Mg2+ restriction, the reabsorption of divalent cations in the CTAL of adult, but not of young, mice undergoes cellular adaptation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004249900197
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    The Ca2+-sensing receptor in the rabbit cortical thick ascending limb (CTAL) is functionally not coupled to phospholipase C (1999)
    Springer
    Pflügers Archiv 437 (1999), S. 716-723 
    Details
    ISSN: 1432-2013
    Keywords: Key words Calcium-sensing receptor ; CTAL ; Cytosolic calcium ; Kidney ; Phospholipase C ; V1a receptor ; RabCaR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  The recently cloned rabbit kidney Ca2+-sensing receptor (RabCaR) was functionally characterized in microperfused rabbit cortical thick ascending limb (CTAL) segments. Reverse transcriptase polymerase chain reaction (RT-PCR) confirmed that this nephron segment contains mRNAs coding for the RabCaR. Elevation of the extracellular Ca2+ concentration ([Ca2+]e) from 1 to 5 mmol l–1 induced an increase in the fluorescence emission ratio (R), thus reflecting an increase in intracellular Ca2+ activity ([Ca2+]i). This increase was inhibited by verapamil, nifedipine and SKF 96365, and potentiated by a previous application of Bay K 8644. Neither verapamil nor Bay K 8644 modified the resting [Ca2+]i. This suggests that the basolateral Ca2+ influx induced by a high [Ca2+]e occurs via verapamil- and dihydropyridine-sensitive Ca2+ channels, which are not open under resting conditions. In contrast to that evoked by antidiuretic hormone (ADH), the [Ca2+]i increase induced by a high [Ca2+]e did not result from an accumulation of inositol phosphates. Neomycin, Gd3+, Mg2+, commonly used agonists of the Ca2+-sensing receptor, did not increase the [Ca2+]i. In the presence of verapamil, ADH still produced a transient [Ca2+]i increase that was not observed in the presence of an increased [Ca2+]e. These results suggest that the RabCaR in rabbit CTAL cells is not functionally coupled to phospholipase C. In conclusion, the high [Ca2+]e-induced [Ca2+]i increase involves verapamil- and dihydropyridine-sensitive Ca2+ channels and is independent of phosphoinositide metabolism. Whether these channels are activated by the RabCaR remains to be elucidated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004240050837
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...