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  1. Article: The calcium receptor in health and disease.

    Hory, B / Roussanne, M C / Drüeke, T B / Bourdeau, A

    Experimental nephrology

    1998  Volume 6, Issue 3, Page(s) 171–179

    Abstract: ... in C cells of the thyroid, in the cortical thick ascending limb (TAL) and collecting duct of the kidney ...

    Abstract The recent cloning of a G-protein-coupled, extracellular calcium [(Ca2+)e]-sensing receptor (CaRG) from the parathyroid, kidney and brain of several species has clarified the molecular mechanisms underlying Ca2+-sensing by parathyroid and other cell types. It has long been suspected that such a receptor existed on parathyroid cells, coupled to intracellular second messengers through guanine nucleotide regulatory (G) protein which is able to recognize and respond to (Ca2+)e. Recently, functional screening of a cDNA library constructed from bovine parathyroid mRNA led to the isolation of a 5.3-kb clone expressing maximal Ca2+-stimulated Cl- currents in oocytes. This 5.3-kb cDNA encodes a protein of 1,085 amino acids with three principal predicted structural domains. The CaRG protein is present in chief parathyroid cells, in C cells of the thyroid, in the cortical thick ascending limb (TAL) and collecting duct of the kidney, and in discrete brain areas. CaRG may play several physiological roles. It is a central element in the control of both parathyroid and calcitonin secretion by (Ca2+)e. Moreover, functional evidence for its participation in the regulation of renal Ca2+ reabsorption in TAL and water reabsorption in the collecting duct has been obtained. Mutations of the CaRG gene are responsible for hereditary and familial parathyroid disorders, and a decrease in CaRG expression has been documented in primary and secondary uremic hyperparathyroidism. The expression of CaRG in several additional organs and tissues allows speculation on the potential involvement in other pathologies.
    MeSH term(s) Calcium-Binding Proteins/genetics ; Calcium-Binding Proteins/metabolism ; GTP-Binding Proteins/genetics ; GTP-Binding Proteins/metabolism ; Humans ; Hyperparathyroidism/metabolism ; Kidney Diseases/metabolism
    Chemical Substances Calcium-Binding Proteins ; GTP-Binding Proteins (EC 3.6.1.-)
    Language English
    Publishing date 1998-05
    Publishing country Switzerland
    Document type Editorial ; Review
    ZDB-ID 1141471-6
    ISSN 1421-9956 ; 1018-7782
    ISSN (online) 1421-9956
    ISSN 1018-7782
    DOI 10.1159/000020520
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  2. Article: Human parathyroid cell proliferation in response to calcium, NPS R-467, calcitriol and phosphate.

    Roussanne, M C / Lieberherr, M / Souberbielle, J C / Sarfati, E / Drüeke, T / Bourdeau, A

    European journal of clinical investigation

    2001  Volume 31, Issue 7, Page(s) 610–616

    Abstract: ... Addition of calcitriol (10-10-10-7 M) to the culture medium suppressed [3H]thymidine incorporation dose ...

    Abstract It remains uncertain how calcium, phosphate and calcitriol regulate parathyroid cell growth. The present study was aimed at examining possible direct effects of these modulators and of the calcimimetic NPS R-467 on parathyroid cell growth in vitro. Cell proliferation was determined by [3H]thymidine incorporation and cell cycle antigen Ki 67 expression in a parathyroid cell culture model derived from uraemic patients. The effect of NPS R-467 on parathyroid hormone (PTH) secretion and intracellular [Ca2+]i response was also examined. Increasing the [Ca2+] in the medium from 0.5 to 1.7 mM increased DNA synthesis (P < 0.005) and the number of Ki 67-positive cells (P < 0.005). However, NPS R-467 (0.01-1 microM) inhibited 3[H]thymidine incorporation by 35% in the presence of 0.5 mM [Ca2+]e. Exposure of cells to Ca2+ or NPS R-467 led to a rapid increase of intracellular Ca2+, although the pattern of increase differed. Addition of calcitriol (10-10-10-7 M) to the culture medium suppressed [3H]thymidine incorporation dose-dependently. Finally, high levels of phosphate (3.5 mM) in the medium led to a significant (P < 0.05) increase in [3H]thymidine incorporation. The observed stimulatory effect of Ca2+ in the medium in vitro appears to be at variance with the inhibitory effect of calcimimetic NPS R-467 in vitro. In an attempt to solve these apparent discrepancies, and based on the notion of a reduced calcium-sensing receptor (CaR) expression in parathyroid tissues of uraemic patients, we hypothesize that Ca2+ may regulate parathyroid cell proliferation via two different pathways, with predominant growth inhibition in cases of high CaR expression or activation, but prevailing stimulation of proliferation in cases of low CaR expression.
    MeSH term(s) Aniline Compounds/pharmacology ; Calcitriol/pharmacology ; Calcium/agonists ; Calcium/pharmacology ; Calcium Signaling ; Cell Division/drug effects ; Cells, Cultured ; Dose-Response Relationship, Drug ; Humans ; Hyperplasia ; Kidney Failure, Chronic ; Parathyroid Diseases ; Parathyroid Glands/cytology ; Parathyroid Glands/drug effects ; Phosphates/pharmacology
    Chemical Substances Aniline Compounds ; NPS R-467 ; Phosphates ; Calcitriol (FXC9231JVH) ; Calcium (SY7Q814VUP)
    Language English
    Publishing date 2001-05-14
    Publishing country England
    Document type Journal Article
    ZDB-ID 186196-7
    ISSN 1365-2362 ; 0014-2972 ; 0960-135X
    ISSN (online) 1365-2362
    ISSN 0014-2972 ; 0960-135X
    DOI 10.1046/j.1365-2362.2001.00809.x
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  3. Article: Absence of response to human parathyroid hormone in athymic mice grafted with human parathyroid adenoma, hyperplasia or parathyroid cells maintained in culture.

    Hory, B G / Roussanne, M C / Rostand, S / Bourdeau, A / Drüeke, T B / Gogusev, J

    Journal of endocrinological investigation

    2000  Volume 23, Issue 5, Page(s) 273–279

    Abstract: In athymic mice we have developed a model of long-term human PTH hypersecretion, using xenotransplantation of respectively parathyroid gland fragments obtained from patients with primary (primary) or secondary (secondary) uremic hyperparathyroidism (HPT), ...

    Abstract In athymic mice we have developed a model of long-term human PTH hypersecretion, using xenotransplantation of respectively parathyroid gland fragments obtained from patients with primary (primary) or secondary (secondary) uremic hyperparathyroidism (HPT), and parathyroid cells maintained in culture from patients with secondary uremic HPT. Both grafted parathyroid tissue fragments and cultured cells induced prolonged and marked secretion of human intact PTH (iPTH) in nude mice. Despite extremely high plasma iPTH levels, hypercalcemia or hypophosphatemia was not observed. Moreover, PTH secretion was not significantly modified by low-calcium, high-phosphate diet for 3 weeks. Four mice which had a mean plasma human iPTH level of 237+/-152 pg/ml for more than 9 months and 4 age-matched, sham-grafted control mice with undetectable human iPTH levels underwent bone histomorphometry examination. No difference was found between the two groups with respect to active bone resorption surface or number of osteoclasts/mm2. We hypothesize that the characteristic deficit of T cell function and of cytokine and growth factor production may protect nude mice with chronic hypersecretion of human PTH from hypercalcemia and bone lesions. We suggest that this strain of mice could be used for better understanding the relationship between cytokines and bone turnover.
    MeSH term(s) Adenoma/physiopathology ; Animals ; Bone and Bones/physiopathology ; Calcium/blood ; Calcium, Dietary/administration & dosage ; Humans ; Hyperplasia ; Male ; Mice ; Mice, Nude ; Neoplasm Transplantation ; Parathyroid Glands/pathology ; Parathyroid Glands/transplantation ; Parathyroid Hormone/blood ; Parathyroid Hormone/secretion ; Parathyroid Neoplasms/physiopathology ; Phosphorus/blood ; Phosphorus, Dietary/administration & dosage ; Transplantation, Heterologous ; Tumor Cells, Cultured
    Chemical Substances Calcium, Dietary ; Parathyroid Hormone ; Phosphorus, Dietary ; Phosphorus (27YLU75U4W) ; Calcium (SY7Q814VUP)
    Language English
    Publishing date 2000-05
    Publishing country Italy
    Document type Journal Article
    ZDB-ID 432272-1
    ISSN 1720-8386 ; 0391-4097 ; 1121-1369
    ISSN (online) 1720-8386
    ISSN 0391-4097 ; 1121-1369
    DOI 10.1007/BF03343723
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  4. Article: Parathyroid hyperplasia in chronic renal failure: role of calcium, phosphate, and calcitriol.

    Roussanne, M C / Duchambon, P / Gogusev, J / Sarfati, E / Bourdeau, A / Drüeke, T B

    Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association

    1999  Volume 14 Suppl 1, Page(s) 68–69

    MeSH term(s) Calcitriol/physiology ; Calcium/physiology ; Humans ; Hyperplasia ; Kidney Failure, Chronic/pathology ; Kidney Failure, Chronic/physiopathology ; Parathyroid Glands/pathology ; Phosphates/physiology
    Chemical Substances Phosphates ; Calcitriol (FXC9231JVH) ; Calcium (SY7Q814VUP)
    Language English
    Publishing date 1999
    Publishing country England
    Document type Journal Article ; Review
    ZDB-ID 90594-x
    ISSN 1460-2385 ; 0931-0509
    ISSN (online) 1460-2385
    ISSN 0931-0509
    DOI 10.1093/ndt/14.suppl_1.68
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  5. Article: Prevalence of hepatitis C virus antibodies in the general population and in selected groups of patients in Limoges, France.

    Ranger, S / Martin, P / Roussanne, M C / Denis, F

    Gut

    1993  Volume 34, Issue 2 Suppl, Page(s) S50–1

    Abstract: In this study of hepatitis C virus (HCV) infection prevalence in France, the prevalence ...

    Abstract In this study of hepatitis C virus (HCV) infection prevalence in France, the prevalence of antibodies to HCV (as tested by second generation ELISA, with RIBA-2 confirmation in ELISA 2 positive samples) was found to be low (0.3%) in the healthy general population. HCV infection prevalence increased in the general population in association with African or Asian origin and risk factors such as bisexuality, previous history of transfusion, and intravenous drug abuse. The prevalence of anti-HCV infection was also higher in specific patient groups infected with HIV or a history of transfusion or haemodialysis.
    MeSH term(s) Female ; France/epidemiology ; Hepacivirus/immunology ; Hepatitis Antibodies/blood ; Hepatitis C/epidemiology ; Hepatitis C Antibodies ; Humans ; Male ; Prevalence ; Risk Factors
    Chemical Substances Hepatitis Antibodies ; Hepatitis C Antibodies
    Language English
    Publishing date 1993
    Publishing country England
    Document type Journal Article
    ZDB-ID 80128-8
    ISSN 1468-3288 ; 0017-5749
    ISSN (online) 1468-3288
    ISSN 0017-5749
    DOI 10.1136/gut.34.2_suppl.s50
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  6. Article: Primo-infection à cytomégalovirus et femmes enceintes: étude épidémiologique portant sur 1100 femmes à Limoges.

    Gambarotto, K / Ranger-Rogez, S / Aubard, Y / Piver, P / Duffetelle, B / Delpeyroux, C / Roussanne, M C / Nicot, T / Denis, F

    Pathologie-biologie

    1997  Volume 45, Issue 6, Page(s) 453–461

    Abstract: During 13 months, 1101 women attending for antenatal care at Limoges University Hospital were prospectively studied to determine the prevalence of Cytomegalovirus (CMV) antibodies: 47.9% of these women were CMV seropositive. Ethnic group was strongly ... ...

    Title translation Primary cytomegalovirus infection and pregnant women: epidemiological study on 1100 women at Limoges.
    Abstract During 13 months, 1101 women attending for antenatal care at Limoges University Hospital were prospectively studied to determine the prevalence of Cytomegalovirus (CMV) antibodies: 47.9% of these women were CMV seropositive. Ethnic group was strongly associated with CMV status: 42.6% of metropolitan and 94.5% of immigrant women were seropositive. Seropositivity was associated with increasing parity and older age. The risk of a susceptible woman to acquire CMV infection during pregnancy is 0.7%. Among the 4 seroconversions, 3 children were infected, with developmentally and neurologically normal status in one case, moderate ear damage in an other case and a disseminated infection in the third case requiring a provoked abortion.
    MeSH term(s) Adult ; Age Factors ; Aged ; Blood Donors/statistics & numerical data ; Cytomegalovirus ; Cytomegalovirus Infections/complications ; Cytomegalovirus Infections/epidemiology ; Cytomegalovirus Infections/ethnology ; Cytomegalovirus Infections/transmission ; Female ; Follow-Up Studies ; France/epidemiology ; Humans ; Infant ; Infant, Newborn ; Middle Aged ; Pregnancy ; Pregnancy Complications, Infectious/epidemiology ; Prospective Studies
    Language French
    Publishing date 1997-06
    Publishing country France
    Document type English Abstract ; Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 207652-4
    ISSN 0369-8114
    ISSN 0369-8114
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  7. Article: Prévalence des marqueurs des virus des hépatites B (Ag HBs, Ag HBe, ADN) et delta, Chez près de dix mille femmes enceintes à Limoges (France).

    Ranger, S / Mounier, M / Denis, F / Alain, J / Baudet, J / Tabaste, J L / Delpeyroux, C / Roussanne, M C

    Pathologie-biologie

    1990  Volume 38, Issue 7, Page(s) 694–699

    Abstract: The risk of perinatal B virus transmission is well known, but is estimated in France on results obtained from blood donors or from urban populations. In the present study, the screening of HBs Ag was carried out during five years (1984-1988), within a ... ...

    Title translation Prevalence of hepatitis B (Hbs Ag, Hbe Ag, DNA) and delta virus markers, in about 10,000 pregnant women in Limoges (France).
    Abstract The risk of perinatal B virus transmission is well known, but is estimated in France on results obtained from blood donors or from urban populations. In the present study, the screening of HBs Ag was carried out during five years (1984-1988), within a sample population of pregnant women (french women: 8,364, immigrant women: 1,206) seen in the university hospital of Limoges. Positive sera for HBs Ag were also tested for the other markers of B virus including specific DNA, and markers of the delta virus. The total seroprevalence of HBs Ag among these women was 0.54%, and was significantly higher in the immigrant women group (2.57%) when compared to that of french women (0.25%). During the same period (1984-1988), the seroprevalence among females blood donor was 0.03%. Among the HBs Ag chronic carrier pregnant women (n = 52), 27% were HBe Ag positive and four of them (31%) had viral DNA in their serum. Viral DNA was found in three women who were HBe Ag negative. Thirteen per cent of the HBs Ag positive pregnant women were infected by the delta virus.
    MeSH term(s) Adolescent ; Adult ; DNA, Viral/analysis ; Enzyme-Linked Immunosorbent Assay ; Female ; France ; Hepatitis B/epidemiology ; Hepatitis B/immunology ; Hepatitis B Surface Antigens/analysis ; Hepatitis B e Antigens/analysis ; Hepatitis B virus/genetics ; Hepatitis D/epidemiology ; Hepatitis D/immunology ; Humans ; Middle Aged ; Pregnancy ; Prevalence
    Chemical Substances DNA, Viral ; Hepatitis B Surface Antigens ; Hepatitis B e Antigens
    Language French
    Publishing date 1990-09
    Publishing country France
    Document type English Abstract ; Journal Article
    ZDB-ID 207652-4
    ISSN 0369-8114
    ISSN 0369-8114
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  8. Article: Activité antibactérienne de la nétilmicine associée à d'autres antibiotiques. Comparaison avec quatre aminosides majeurs.

    Cluzel, M / Sirot, J / Chanal, M / Sirot, D / Roussanne, M C

    Pathologie-biologie

    1982  Volume 30, Issue 6, Page(s) 376–379

    Abstract: We studied in vitro bactericidal effects of netilmicin combined with other antibiotics, comparing with that obtained with other aminoglycosides combinations. We used strains of Streptococci and Gram negative rods tested versus 11 antibiotics : penicillin ...

    Title translation Antibacterial activity of netilmicin in combination with other antibiotics. Comparison with other aminoglycosides (author's transl).
    Abstract We studied in vitro bactericidal effects of netilmicin combined with other antibiotics, comparing with that obtained with other aminoglycosides combinations. We used strains of Streptococci and Gram negative rods tested versus 11 antibiotics : penicillin (P), ampicillin (Am), carbenicillin (Cb), cefalotin (Cth), cefazolin (Cfz), cefradin (Cfa), cefoxitin (Cxt), cefotaxime (CTX), erythromycin (E), pristinamycin (Pr), vancomycin (V). These were combined with streptomycin (Sm), tobramycin (To), amikacin (Ak), gentamicin (G) and netilmicin (Nl). First of all, we noted the high bactericidal power of Nl, whatever the strains tested. Against Streptococci, the activity of P + Nl and Am + Nl were equivalent or superior to that of P + G and Am + G. Among cephalosporins, we noted a synergistic effect of Ctx + Nl which did not exist with Ctx + G. In the same way, E + Nl showed synergism whereas E + G didn't. V + Nl combinations, as active upon Streptococci as V + G, are more active than V + G upon Enterococci. Against Gram negative bacilli, we observed good effects with Cb + Nl. Cephalosporins combinations were also interesting : Cfz + Nl were as active Cfz + G but Czt + Nl showed higher synergistic effect than Cxt + G. Ctx + Nl combinations were effective upon E. coli.
    MeSH term(s) Aminoglycosides/pharmacology ; Anti-Bacterial Agents/pharmacology ; Bacteria/drug effects ; Cephalosporins/pharmacology ; Drug Synergism ; Enterobacteriaceae/drug effects ; Gentamicins/pharmacology ; Netilmicin/pharmacology ; Penicillins/pharmacology ; Streptococcus/drug effects
    Chemical Substances Aminoglycosides ; Anti-Bacterial Agents ; Cephalosporins ; Gentamicins ; Penicillins ; Netilmicin (4O5J85GJJB)
    Language French
    Publishing date 1982-06
    Publishing country France
    Document type Comparative Study ; English Abstract ; Journal Article
    ZDB-ID 207652-4
    ISSN 0369-8114
    ISSN 0369-8114
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  9. Article: Persistence of Ca2+-sensing receptor expression in functionally active, long-term human parathyroid cell cultures.

    Roussanne, M C / Gogusev, J / Hory, B / Duchambon, P / Souberbielle, J C / Nabarra, B / Pierrat, D / Sarfati, E / Drüeke, T / Bourdeau, A

    Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research

    1998  Volume 13, Issue 3, Page(s) 354–362

    Abstract: An original human parathyroid cell culture model from uremic patients with IIo hyperparathyroidism has been developed, with its main feature being long-term functionally active viability up to 5 months, as assessed by persistent responsiveness to changes ...

    Abstract An original human parathyroid cell culture model from uremic patients with IIo hyperparathyroidism has been developed, with its main feature being long-term functionally active viability up to 5 months, as assessed by persistent responsiveness to changes of extracellular Ca2+ concentrations ([Ca2+]e). In addition to the inhibitory effect of increasing [Ca2+]e, increasing extracellular phosphate exerted a biphasic effect on parathyroid hormone (PTH) secretion. The presence of the Ca2+-sensing receptor (CaR), on which depends the response to [Ca2+]e and its persistence, has been demonstrated in our culture system both by direct detection and by inhibition of its activity. CaR protein was detected by Western blot analysis with a specific anti-CaR antibody. CaR gene transcripts have been identified by reverse transcription-polymerase chain reaction analysis. mRNA (by in situ hybridization) and protein (by immunocytochemistry) expression were detected for both CaR and PTH. Adding a specific anti-CaR antibody to the medium induced a marked reduction of low [Ca2+]e-stimulated PTH release, which decreased to levels equivalent to those obtained in high [Ca2+]e medium. The described long-term functionality could be due to several factors, including the clustered cell type of culture yielded by our preparation procedure, the growth characteristics of hyperplastic uremic tissue, and the use of a phosphate-rich medium. The present model, because of its long-term functionality, is a unique tool for the exploration of PTH synthesis and secretion and for studies of parathyroid cell growth in vitro.
    MeSH term(s) Animals ; Calcium/pharmacology ; Cell Division/drug effects ; Cell Survival ; Cells, Cultured ; Gene Expression Regulation/drug effects ; Humans ; Hyperparathyroidism/physiopathology ; Mice ; Parathyroid Glands/drug effects ; Parathyroid Glands/metabolism ; Parathyroid Glands/ultrastructure ; Parathyroid Hormone/genetics ; Parathyroid Hormone/secretion ; Phosphorus/pharmacology ; RNA, Messenger/analysis ; Receptors, Calcium-Sensing ; Receptors, Cell Surface/drug effects ; Receptors, Cell Surface/metabolism ; Receptors, Parathyroid Hormone/metabolism ; Transcription, Genetic ; Uremia/physiopathology
    Chemical Substances Parathyroid Hormone ; RNA, Messenger ; Receptors, Calcium-Sensing ; Receptors, Cell Surface ; Receptors, Parathyroid Hormone ; Phosphorus (27YLU75U4W) ; Calcium (SY7Q814VUP)
    Language English
    Publishing date 1998-03
    Publishing country United States
    Document type Journal Article
    ZDB-ID 632783-7
    ISSN 1523-4681 ; 0884-0431
    ISSN (online) 1523-4681
    ISSN 0884-0431
    DOI 10.1359/jbmr.1998.13.3.354
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